Draft California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name:	Santa Margarita River (Upper)
Water Body ID:	CAR9022200020011001141050
Water Body Type:	River & Stream

DECISION ID	128037	Region 9
Santa Margarita River (Upper)

Pollutant:	Indicator Bacteria
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the four samples exceed the STV threshold for E. coli. This sample size is insufficient to determine beneficial use support with the statistical power and confidence required by the Listing Policy; the minimum sample size necessary to delist is 26. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of four samples exceeded the E. coli water quality threshold for the protection of REC-1, and this sample size is insufficient information in Table 4.2. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met. The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective. In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy. For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody. No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:	The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective. In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy. For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody. No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 128037, Indicator Bacteria Region 9      Santa Margarita River (Upper)
LOE ID:	76574
Pollutant:	Enterococcus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Water Contact Recreation
Number of Samples:	14
Number of Exceedances:	7
Data and Information Type:	PATHOGEN MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 7 of 14 samples exceed the criterion for Enterococci.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Samples shall not exceed 61 organisms per 100 ml for enterococcus in waters designated for REC I beneficial use (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 128037, Indicator Bacteria Region 9      Santa Margarita River (Upper)
LOE ID:	76582
Pollutant:	Fecal Coliform
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Water Contact Recreation
Number of Samples:	14
Number of Exceedances:	3
Data and Information Type:	PATHOGEN MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 14 samples exceed the criterion for Coliform, Fecal.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In waters designated for water contact recreation (REC I), the fecal coliform concentration shall not exceed 400 MPN/100 ml.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 128037, Indicator Bacteria Region 9      Santa Margarita River (Upper)
LOE ID:	76530
Pollutant:	Total Coliform
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Water Contact Recreation
Number of Samples:	14
Number of Exceedances:	1
Data and Information Type:	PATHOGEN MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 14 samples exceed the criterion for Coliform, Total.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxicsubstances in concentrations which are toxic to,or which produce detrimental physiologicalresponses in human, plant, animal, or indigenousaquatic life (Basin Plan).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In waters designated for water contact recreation (REC I), the total coliform concentration shall not exceed 10000 MPN/100 ml (CDPH 2006).
Guideline Reference:	Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 128037, Indicator Bacteria Region 9      Santa Margarita River (Upper)
LOE ID:	220627
Pollutant:	Escherichia coli (E. coli)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Water Contact Recreation
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PATHOGEN MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference:	Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site(s), station(s): 902USM828
Temporal Representation:	The samples were collected between the days of 2014-05-14 and 2018-05-30 .
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111312	Region 9
Santa Margarita River (Upper)

Pollutant:	Iron
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Nine lines of evidence are available in the administrative record to assess pollutant. Five of the 17 samples exceed the water quality threshood for the MUN beneficial use. Zero of 13 samples exceed the water quality threshood for the WARM/COLD beneficial use. The minimum sample size needed to delist is 28. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 17 samples exceeded the water quality threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142843
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142969
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142820
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142574
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142591
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142819
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	143024
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142573
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	76589
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Iron.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for iron is 0.3 mg/L (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	76591
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 4 samples exceed the criterion for Iron.
Data Reference:	Data for Metals, Nutrients, and Inorganics from the County of San Diego Sandia Creek and Santa Margarita River, 2004-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for iron is 0.3 mg/L (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River upstream of Stone Creek - 902SMRGorge]
Temporal Representation:	Data was collected over the time period 12/6/2007-5/14/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	76588
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Iron.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Iron objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 0.3 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142571
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	76590
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Iron.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Iron objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 0.3 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142587
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142826
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142970
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142717
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142841
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142840
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142665
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142755
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 6 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Iron is 0.3 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111312, Iron Region 9      Santa Margarita River (Upper)
LOE ID:	142577
Pollutant:	Iron
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Iron.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	111316	Region 9
Santa Margarita River (Upper)

Pollutant:	Manganese
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess pollutant. Five of the 17 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 17 samples exceeded the threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143297
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143322
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143240
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 6 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143302
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	76613
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Manganese.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for manganese is 0.05 mg/L (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	76615
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 4 samples exceed the criterion for Manganese.
Data Reference:	Data for Metals, Nutrients, and Inorganics from the County of San Diego Sandia Creek and Santa Margarita River, 2004-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for manganese is 0.05 mg/L (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River upstream of Stone Creek - 902SMRGorge]
Temporal Representation:	Data was collected over the time period 12/6/2007-5/14/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report.
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	76612
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Manganese.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Manganese objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 0.05 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	76614
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Manganese.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Manganese objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 0.05 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143278
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111316, Manganese Region 9      Santa Margarita River (Upper)
LOE ID:	143282
Pollutant:	Manganese
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Manganese.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Manganese is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	127258	Region 9
Santa Margarita River (Upper)

Pollutant:	Nitrogen
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2023
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Eleven lines of evidence are available in the administrative record to assess pollutant. Sixteen of the 30 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Sixteen of the 30 samples exceed the water quality threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	143963
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	143844
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	144021
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	144057
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	10
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 10 of 17 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	143966
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	143812
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	143945
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	144096
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	144064
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	144023
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	10
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 10 of 17 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127258, Nitrogen Region 9      Santa Margarita River (Upper)
LOE ID:	21194
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality:	Two of the four samples collected at Santa Margarita River on January 2003, April 2003, May 2003, and September 2003 show excessive nitrogen concentrations. (SWAMP, 2007).
Data Reference:	Monitoring data for Region 9
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:	The first two sampling events occurred between storm events and high base flow respectively. The third and fourth occurred during declining and minimum base flow respectively.
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):	2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA

DECISION ID	111323	Region 9
Santa Margarita River (Upper)

Pollutant:	Phosphorus
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2019
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Twelve lines of evidence are available in the administrative record to assess pollutant. Nine of the 29 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Nine of the 29 samples exceed the threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145640
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2017-05-25
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145569
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145641
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145942
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	146019
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	4
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 4 of 18 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145817
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2017-05-25
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145747
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	146002
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	145869
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	4
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 4 of 18 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	146025
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	7407
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	4
Data and Information Type:	Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality:	All four samples collected exceeded the total phosphorus water quality objective. Samples were collected between January 2003 and September 2003 for the SWAMP program.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters.
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SMSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:	The first two sampling events occurred between storm events and high base flow respectively. The third and fourth occurred during declining and minimum base flow respectively.
QAPP Information:	Puckett, M. 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program ("SWAMP"). California Department of Fish and Game, Monterey, CA.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	4731
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Not Recorded
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	Not Specified
Data Used to Assess Water Quality:	Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference:	Placeholder reference pre-2006 303(d)
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Unspecified
Objective/Criterion Reference:	Placeholder reference pre-2006 303(d)
Evaluation Guideline:	Unspecified
Guideline Reference:	Placeholder reference pre-2006 303(d)
Spatial Representation:	Unspecified
Temporal Representation:	Unspecified
Environmental Conditions:	Unspecified
QAPP Information:	Unspecified
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	24978
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	3
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Selenastrum capricornutum- Six samples were collected and none showed significant toxicity levels (SL) as determined by the Selenastrum capricornutum growth test. Ceriodaphnia dubia- Six samples were collected and two samples show significant toxicity levels (SL) as determined by the Ceriodaphnia dubia survival/reproductive. Hyalella azteca- Six samples were collected and one sample show significant toxicity levels (SL) as determined by the Hyalella azteca growth/survival test. Samples were collected November 2001 through February 2006.
Data Reference:	San Diego Stormwater Copermittees Jurisdiction Urban Runoff Managment Program. Final Report. Baseline Long Term Effectiveness Assessment
	Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration (U.S. EPA, 2002).
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	Samples were collected at the monitoring stations Santa Margarita 1 located on the main stem of the Santa Margarita River.
Temporal Representation:	Samples were collected on the following dates: January 14-15, April 15-16, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	76503
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	One sample was collected to evaluate water toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Ceriodaphnia dubia. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL, Significant compared to negative control based on statistical test, less than stated alpha level, AND less than the evaluation threshold (both criteria are met).
Guideline Reference:	SWAMP_Memo_Toxicity_Data_Intrepretation
Spatial Representation:	The sample was collected at station 902S00565.
Temporal Representation:	The sample was collected in May 2009.
Environmental Conditions:
QAPP Information:	Data quality is good. Data results were recorded in the SWAMP database and followed SWAMP protocols.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111323, Phosphorus Region 9      Santa Margarita River (Upper)
LOE ID:	21402
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Four samples were collected at Santa Margarita 1 station 902SSMR1 from January to September 2003, they showed significant toxicity levels (SL) in the following test: Selenastrum algae growth test - Two of the four samples. Ceriodaphnia dubia survival and reproduction. No toxicity was observed.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference:	Monitoring data for Region 9
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on the following dates: January 15, April 16, May 14, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID	111330	Region 9
Santa Margarita River (Upper)

Pollutant:	Toxicity
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.6 of the Listing Policy. Under this section, a single line of evidence is necessary to assess listing status. Twelve lines of evidence are available in the administrative record to assess pollutant. Six of the 25 samples exceed the water quality threshold. An insufficient number of sediment samples is available. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of 25 water samples exceeded the water quality threshold, and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	30288
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Sediment
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Two samples were collected at Santa Margarita 1 station 902SSMR1 from January to September 2003, they showed significant toxicity levels (SL) in the following test: Hyalella azteca. No toxicity was observed.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference:	Monitoring data for Region 9
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on the following dates: January 15, April 16, May 14, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	24978
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	3
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Selenastrum capricornutum- Six samples were collected and none showed significant toxicity levels (SL) as determined by the Selenastrum capricornutum growth test. Ceriodaphnia dubia- Six samples were collected and two samples show significant toxicity levels (SL) as determined by the Ceriodaphnia dubia survival/reproductive. Hyalella azteca- Six samples were collected and one sample show significant toxicity levels (SL) as determined by the Hyalella azteca growth/survival test. Samples were collected November 2001 through February 2006.
Data Reference:	San Diego Stormwater Copermittees Jurisdiction Urban Runoff Managment Program. Final Report. Baseline Long Term Effectiveness Assessment
	Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration (U.S. EPA, 2002).
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	Samples were collected at the monitoring stations Santa Margarita 1 located on the main stem of the Santa Margarita River.
Temporal Representation:	Samples were collected on the following dates: January 14-15, April 15-16, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	76503
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	One sample was collected to evaluate water toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Ceriodaphnia dubia. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL, Significant compared to negative control based on statistical test, less than stated alpha level, AND less than the evaluation threshold (both criteria are met).
Guideline Reference:	SWAMP_Memo_Toxicity_Data_Intrepretation
Spatial Representation:	The sample was collected at station 902S00565.
Temporal Representation:	The sample was collected in May 2009.
Environmental Conditions:
QAPP Information:	Data quality is good. Data results were recorded in the SWAMP database and followed SWAMP protocols.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	21402
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Four samples were collected at Santa Margarita 1 station 902SSMR1 from January to September 2003, they showed significant toxicity levels (SL) in the following test: Selenastrum algae growth test - Two of the four samples. Ceriodaphnia dubia survival and reproduction. No toxicity was observed.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference:	Monitoring data for Region 9
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on the following dates: January 15, April 16, May 14, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134672
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 2 samples collected by SMC Regional Watershed Monitoring for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( SMC04661 )
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16.
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134673
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 2 samples collected by SMC Regional Watershed Monitoring for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( SMC04661 )
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16.
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134657
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 1 samples collected by RWB9 So. CA Stormwater Monitoring Coalition for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( 902S05173 )
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17.
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134689
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 4 samples collected by San Diego Region for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival, Ceriodaphnia dubia, for Reproduction, Pimephales promelas, for Survival, Pimephales promelas, for Biomass (wt/orig indiv), Pimephales promelas, for Growth (wt/surv indiv)
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( 902USM828 )
Temporal Representation:	The samples were collected between the dates of 2015-06-04 and 2018-05-30.
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134690
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 4 samples collected by San Diego Region for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Total Cell Count, Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival, Ceriodaphnia dubia, for Reproduction, Pimephales promelas, for Survival, Pimephales promelas, for Biomass (wt/orig indiv), Pimephales promelas, for Growth (wt/surv indiv)
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( 902USM828 )
Temporal Representation:	The samples were collected between the dates of 2015-06-04 and 2018-05-30.
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134656
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	0 of the 1 samples collected by RWB9 So. CA Stormwater Monitoring Coalition for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( 902S05173 )
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17.
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134718
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	7
Number of Exceedances:	1
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	1 of the 7 samples collected by San Diego Region NPDES for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Total Cell Count, Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Growth (Chlorophyll a), Hyalella azteca, for Survival, Ceriodaphnia dubia, for Reproduction
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( SMR-MLS-2 )
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31.
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111330, Toxicity Region 9      Santa Margarita River (Upper)
LOE ID:	134719
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	7
Number of Exceedances:	1
Data and Information Type:	TOXICITY TESTING
Data Used to Assess Water Quality:	1 of the 7 samples collected by San Diego Region NPDES for Santa Margarita River (Upper) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Total Cell Count, Ceriodaphnia dubia, for Survival, Selenastrum capricornutum, for Growth (Chlorophyll a), Hyalella azteca, for Survival, Ceriodaphnia dubia, for Reproduction
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 station. Monitoring site: ( SMR-MLS-2 )
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31.
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111342	Region 9
Santa Margarita River (Upper)

Pollutant:	Aldicarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111342, Aldicarb Region 9      Santa Margarita River (Upper)
LOE ID:	139532
Pollutant:	Aldicarb
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldicarb. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111342, Aldicarb Region 9      Santa Margarita River (Upper)
LOE ID:	139531
Pollutant:	Aldicarb
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldicarb. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111344	Region 9
Santa Margarita River (Upper)

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139687
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139672
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139506
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139580
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139719
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	76565
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Alkalinity as CaCO3.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The Alkalinity as CaCO3 criteria for the protection of freshwater aquatic life is 20000 ug/L (National Recommended Water Quality Criteria, 2009).
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected over the time period 4/27/2009-5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	76564
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Alkalinity as CaCO3.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The Alkalinity as CaCO3 criteria for the protection of freshwater aquatic life is 20000 ug/L (National Recommended Water Quality Criteria, 2009).
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected over the time period 4/27/2009-5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139837
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139741
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	140090
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139490
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111344, Alkalinity as CaCO3 Region 9      Santa Margarita River (Upper)
LOE ID:	139896
Pollutant:	Alkalinity as CaCO3
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111353	Region 9
Santa Margarita River (Upper)

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	76570
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	76569
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	76566
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	139937
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	139973
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	139842
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	140078
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	139995
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111353, Aluminum Region 9      Santa Margarita River (Upper)
LOE ID:	139935
Pollutant:	Aluminum
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	127766	Region 9
Santa Margarita River (Upper)

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	26402
Pollutant:	Alkalinity as CaCO3 | Ammonia | Manganese | Nickel | Orthophosphate | Total Kjeldahl Nitrogen (TKN) | Total Suspended Solids (TSS)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Not Recorded
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	37
Number of Exceedances:	0
Data and Information Type:	Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality:	37 samples were collected at Santa Margarita Creek station 902SMSMR1 during the months of January 2003, April 2003, May 2003, and September 2003, for conventioanl inorganics analyses. None of the 37 samples showed excessive concentrations.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Alkalinity as CaCO3 20 mg/l, ammonia as N 0.025 mg/l, nitrite as N 1.mg/l, nitrogen total Kjeldahl (If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used), ortho phosphate as P total 0.05 mg/l, sulfate 250 mg/l, total suspended solids narrative: Waters shall not contain suspended solids in concentrations of solids that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Water samples were collected at Santa Margarita Creek station 902SMSMR1; (Latitude 33.4741, Longitude -117.1414).
Temporal Representation:	Water samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:
QAPP Information:	Quality control for chemical analysis portion of this study was conducted in accordance with the California Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185231
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	76572
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Ammonia As N, Total.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-9/4/2003.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	76571
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Ammonia As N, Total.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185090
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185086
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185087
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-10-19 and 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185089
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185088
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185274
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127766, Ammonia Region 9      Santa Margarita River (Upper)
LOE ID:	185134
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Ammonia as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference:	Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-10-19 and 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	115501	Region 9
Santa Margarita River (Upper)

Pollutant:	Ammonia (Unionized)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185447
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-07-18 to 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185281
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185409
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185305
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185426
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Data for this waterbody was collected over the date range 2010-10-19 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185449
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Data for this waterbody was collected over the date range 2010-10-19 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185279
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 115501, Ammonia (Unionized) Region 9      Santa Margarita River (Upper)
LOE ID:	185411
Pollutant:	Ammonia (Unionized)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-07-18 to 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition

DECISION ID	111297	Region 9
Santa Margarita River (Upper)

Pollutant:	Antimony
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 17 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 17 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111297, Antimony Region 9      Santa Margarita River (Upper)
LOE ID:	77890
Pollutant:	Antimony
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Antimony.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for antimony is .006 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111297, Antimony Region 9      Santa Margarita River (Upper)
LOE ID:	139806
Pollutant:	Antimony
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Antimony.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for antimony is .006 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111297, Antimony Region 9      Santa Margarita River (Upper)
LOE ID:	140100
Pollutant:	Antimony
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Antimony.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for antimony is .006 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111298	Region 9
Santa Margarita River (Upper)

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Thirty-three lines of evidence are available in the administrative record to assess this pollutant. Zero of 28 samples exceed the water quality threshold in water for the COLD beneficial use, zero of 28 samples exceed the water quality threshold in water for the MUN beneficial use, and zero of two samples exceed the water quality threshold in sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 28 samples exceed the water quality threshold in water for the COLD beneficial use, zero of 28 samples exceed the water quality threshold in water for the MUN beneficial use, zero of two samples exceed the water quality threshold in sediment, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	76578
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	76575
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139926
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139945
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140223
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140206
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139813
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139888
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140389
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140350
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139946
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140459
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140160
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140048
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140276
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140207
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140346
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	135339
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	139905
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140454
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140114
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140349
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140328
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	135303
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140123
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140178
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140220
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	140397
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Arsenic.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	76579
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	77898
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	76577
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	76576
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111298, Arsenic Region 9      Santa Margarita River (Upper)
LOE ID:	77897
Pollutant:	Arsenic
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

DECISION ID	111299	Region 9
Santa Margarita River (Upper)

Pollutant:	Atrazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111299, Atrazine Region 9      Santa Margarita River (Upper)
LOE ID:	140569
Pollutant:	Atrazine
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Atrazine.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111299, Atrazine Region 9      Santa Margarita River (Upper)
LOE ID:	140145
Pollutant:	Atrazine
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Atrazine.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111300	Region 9
Santa Margarita River (Upper)

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Twenty-seven lines of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold for the COLD beneficial use, zero of the 41 samples exceed the water quality threshold for the MUN beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 41 samples exceed the water quality threshold for the COLD beneficial use, zero of the 41 samples exceed the water quality threshold for the MUN beneficial use, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76599
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76600
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76606
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Cadmium.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76593
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76592
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76601
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	77902
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140739
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140860
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140950
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140831
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140581
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76603
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Cadmium.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	76602
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140858
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	136050
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cadmium. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140949
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140596
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140704
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140667
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	136024
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cadmium. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	141017
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140716
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140700
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	141058
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140922
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111300, Cadmium Region 9      Santa Margarita River (Upper)
LOE ID:	140566
Pollutant:	Cadmium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cadmium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition

DECISION ID	111301	Region 9
Santa Margarita River (Upper)

Pollutant:	Carbofuran
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111301, Carbofuran Region 9      Santa Margarita River (Upper)
LOE ID:	141019
Pollutant:	Carbofuran
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Carbofuran.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for Carbofuran is .0.018 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111302	Region 9
Santa Margarita River (Upper)

Pollutant:	Chlordane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111302, Chlordane Region 9      Santa Margarita River (Upper)
LOE ID:	136039
Pollutant:	Chlordane
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111302, Chlordane Region 9      Santa Margarita River (Upper)
LOE ID:	136369
Pollutant:	Chlordane
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlordane. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111303	Region 9
Santa Margarita River (Upper)

Pollutant:	Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	141269
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Agricultural Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	76607
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chloride.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Chloride objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 250 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	76608
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chloride.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The recommended secondary maximum contamination level acceptable to consumers of drinking water is 250 mg/L.
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	141201
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	140997
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	140729
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	140872
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Agricultural Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	141405
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	141341
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	76610
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chloride.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Chloride objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 250 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111303, Chloride Region 9      Santa Margarita River (Upper)
LOE ID:	140936
Pollutant:	Chloride
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chloride.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition

DECISION ID	111304	Region 9
Santa Margarita River (Upper)

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of 18 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of 28 samples exceed the water quality threshold for the MUN beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 18 samples exceed the threshold for the WARM/COLD beneficial use, zero of 28 samples exceed the water quality threshold for the MUN beneficial use, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	76616
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Chlorpyrifos.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	77913
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	8
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Chlorpyrifos.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for chlorpyrifos is 2.1 µg/L.
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance (902SMG09), Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road, 902SMG10)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	219732
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	219699
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	219697
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	77910
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for chlorpyrifos is 2.1 µg/L.
Guideline Reference:	2011 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	77909
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	141435
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The 2018 USEPA drinking water health advisory for chlorpyrifos is 2 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	141159
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Chlorpyrifos. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The 2018 USEPA drinking water health advisory for chlorpyrifos is 2 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111304, Chlorpyrifos Region 9      Santa Margarita River (Upper)
LOE ID:	219684
Pollutant:	Chlorpyrifos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference:	Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111349	Region 9
Santa Margarita River (Upper)

Pollutant:	Chromium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Twenty-four lines of evidence are available in the administrative record to assess this pollutant. Zero of 27 water samples exceed the water quality threshold for the MUN beneficial use, zero of 28 water samples exceed the water quality threshold for the COLD beneficial use, and zero of two sediment samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 27 water samples exceed the water quality threshold for the MUN beneficial use, zero of 28 water samples exceed the water quality threshold for the COLD beneficial use, and this sample size is sufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. There is not associated sediment toxicity. 4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76486
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76623
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76624
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76485
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium. Since the chromium species was not identified, the data point(s) were assessed using both the Chromium III criteria which is hardness-dependent, and the criterion continuous concentration (4-day average) to protect aquatic life in freshwater for chromium VI which is 11 ug/L and is not hardness dependent.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Chromium to protect aquatic life in freshwater. The dissolved Chromium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76626
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved chromium to protect aquatic life in freshwater. The dissolved Chromium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	76625
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium. Since the chromium species was not identified, the data point(s) were assessed using both the Chromium III criteria which is hardness-dependent, and the criterion continuous concentration (4-day average) to protect aquatic life in freshwater for chromium VI which is 11 ug/L and is not hardness dependent.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved chromium to protect aquatic life in freshwater. The dissolved Chromium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141550
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141303
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141210
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141394
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	136152
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141216
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	136102
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141526
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141571
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141524
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141273
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141375
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141306
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141182
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141107
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141302
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141109
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111349, Chromium Region 9      Santa Margarita River (Upper)
LOE ID:	141147
Pollutant:	Chromium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	111305	Region 9
Santa Margarita River (Upper)

Pollutant:	Copper
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Twenty-seven lines of evidence are available in the administrative record to assess this pollutant. Zero of two samples (sediment) and one of 41 samples (water) exceeded the water quality threshold for the COLD beneficial use. Zero of 41 samples exceed the water quality threshold for the MUN beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 41 samples exceed the water quality threshold for the COLD beneficial use, zero of 41 samples exceed the water quality threshold for the MUN beneficial use, and this sample size is sufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. 4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76547
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved copper to protect aquatic life in freshwater. The dissolved copper criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76489
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Copper to protect aquatic life in freshwater. The dissolved Copper criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76536
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Copper.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76488
Pollutant:	Copper
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76487
Pollutant:	Copper
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	77880
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76490
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141582
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	136666
Pollutant:	Copper
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141583
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141730
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141934
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141686
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141758
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141756
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141627
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141598
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141915
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141757
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141728
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141595
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	136616
Pollutant:	Copper
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141601
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141492
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	141628
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Copper.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76535
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved copper to protect aquatic life in freshwater. The dissolved copper criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111305, Copper Region 9      Santa Margarita River (Upper)
LOE ID:	76537
Pollutant:	Copper
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Copper.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.

DECISION ID	111346	Region 9
Santa Margarita River (Upper)

Pollutant:	Cyfluthrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOEs 76548 and 76549 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:	LOEs 76548 and 76549 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	142014
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2014-05-14 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	136640
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	227889
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Cyfluthrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	227856
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Cyfluthrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	142046
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	136553
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	142001
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2014-05-14 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	136585
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	136605
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	141832
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 10 samples were collected, 10 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	141844
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	142012
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 10 samples were collected, 10 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	141920
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2017-02-19 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111346, Cyfluthrin Region 9      Santa Margarita River (Upper)
LOE ID:	141849
Pollutant:	Cyfluthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2017-02-19 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111337	Region 9
Santa Margarita River (Upper)

Pollutant:	Cypermethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOEs 76559 and 76558 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:	LOEs 76559 and 76558 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136747
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136819
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142106
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	141814
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136711
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227711
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Cypermethrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227827
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Cypermethrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136798
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	141843
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	141884
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142105
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111337, Cypermethrin Region 9      Santa Margarita River (Upper)
LOE ID:	141871
Pollutant:	Cypermethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Cypermethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	127277	Region 9
Santa Margarita River (Upper)

Pollutant:	DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 127277, DDD (Dichlorodiphenyldichloroethane) Region 9      Santa Margarita River (Upper)
LOE ID:	136905
Pollutant:	DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127277, DDD (Dichlorodiphenyldichloroethane) Region 9      Santa Margarita River (Upper)
LOE ID:	136888
Pollutant:	DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	127316	Region 9
Santa Margarita River (Upper)

Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 127316, DDE (Dichlorodiphenyldichloroethylene) Region 9      Santa Margarita River (Upper)
LOE ID:	136701
Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127316, DDE (Dichlorodiphenyldichloroethylene) Region 9      Santa Margarita River (Upper)
LOE ID:	136714
Pollutant:	DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	127376	Region 9
Santa Margarita River (Upper)

Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 127376, DDT (Dichlorodiphenyltrichloroethane) Region 9      Santa Margarita River (Upper)
LOE ID:	136806
Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127376, DDT (Dichlorodiphenyltrichloroethane) Region 9      Santa Margarita River (Upper)
LOE ID:	136770
Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111347	Region 9
Santa Margarita River (Upper)

Pollutant:	Deltamethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136738
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227640
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Deltamethrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227684
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Deltamethrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142144
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Deltamethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136774
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 4 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227685
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Deltamethrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136840
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 4 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142280
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142180
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Deltamethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142298
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Deltamethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142094
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Deltamethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	142057
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111347, Deltamethrin Region 9      Santa Margarita River (Upper)
LOE ID:	136962
Pollutant:	Deltamethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111351	Region 9
Santa Margarita River (Upper)

Pollutant:	Demeton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 19 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 19 samples exceeded the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111351, Demeton Region 9      Santa Margarita River (Upper)
LOE ID:	142133
Pollutant:	Demeton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Demeton, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111351, Demeton Region 9      Santa Margarita River (Upper)
LOE ID:	142166
Pollutant:	Demeton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Demeton, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111351, Demeton Region 9      Santa Margarita River (Upper)
LOE ID:	142081
Pollutant:	Demeton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Demeton, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111351, Demeton Region 9      Santa Margarita River (Upper)
LOE ID:	142218
Pollutant:	Demeton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Demeton, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111306	Region 9
Santa Margarita River (Upper)

Pollutant:	Diazinon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 27 samples exceed the water quality threshold in water. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 27 samples exceeded the water quality threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	77891
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142234
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Diazinon. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142137
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Diazinon.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142321
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Diazinon.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for diazinon is 1.4 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142270
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Diazinon.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142284
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Diazinon. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for diazinon is 1.4 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	142085
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the water quality threshold for Diazinon. Although a total of 5 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	77893
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	8
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Diazinon.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Public Health (CDPH) Notification Level for Diazinon is 1.2 ug/L.
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	76573
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	8
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Diazinon.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference:	Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111306, Diazinon Region 9      Santa Margarita River (Upper)
LOE ID:	77892
Pollutant:	Diazinon
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Public Health (CDPH) Notification Level for Diazinon is 1.2 ug/L.
Guideline Reference:	2011 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

DECISION ID	111307	Region 9
Santa Margarita River (Upper)

Pollutant:	Dichlorvos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111307, Dichlorvos Region 9      Santa Margarita River (Upper)
LOE ID:	142257
Pollutant:	Dichlorvos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111307, Dichlorvos Region 9      Santa Margarita River (Upper)
LOE ID:	142460
Pollutant:	Dichlorvos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111307, Dichlorvos Region 9      Santa Margarita River (Upper)
LOE ID:	142072
Pollutant:	Dichlorvos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 17 samples were collected, 17 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2010-09-15 to 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111307, Dichlorvos Region 9      Santa Margarita River (Upper)
LOE ID:	142443
Pollutant:	Dichlorvos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 17 samples were collected, 17 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2010-09-15 to 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111308	Region 9
Santa Margarita River (Upper)

Pollutant:	Dieldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111308, Dieldrin Region 9      Santa Margarita River (Upper)
LOE ID:	137057
Pollutant:	Dieldrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Dieldrin .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111308, Dieldrin Region 9      Santa Margarita River (Upper)
LOE ID:	137056
Pollutant:	Dieldrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Dieldrin .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111339	Region 9
Santa Margarita River (Upper)

Pollutant:	Dimethoate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. Zero of the 19 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 19 samples exceeded the threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142546
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142418
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Health Services notification level for dimethoate is 1 µg/L.
Guideline Reference:	CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142331
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Health Services notification level for dimethoate is 1 µg/L.
Guideline Reference:	CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142505
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142334
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111339, Dimethoate Region 9      Santa Margarita River (Upper)
LOE ID:	142431
Pollutant:	Dimethoate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111309	Region 9
Santa Margarita River (Upper)

Pollutant:	Disulfoton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 18 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 18 samples exceed the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111309, Disulfoton Region 9      Santa Margarita River (Upper)
LOE ID:	142535
Pollutant:	Disulfoton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	16
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Disulfoton.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for disulfoton is 0.7 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111309, Disulfoton Region 9      Santa Margarita River (Upper)
LOE ID:	142538
Pollutant:	Disulfoton
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Disulfoton.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for disulfoton is 0.7 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111310	Region 9
Santa Margarita River (Upper)

Pollutant:	Dyfonate (Fonofos or Fonophos)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111310, Dyfonate (Fonofos or Fonophos) Region 9      Santa Margarita River (Upper)
LOE ID:	142661
Pollutant:	Dyfonate (Fonofos or Fonophos)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fonofos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111310, Dyfonate (Fonofos or Fonophos) Region 9      Santa Margarita River (Upper)
LOE ID:	142662
Pollutant:	Dyfonate (Fonofos or Fonophos)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fonofos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fonofos is the maximum acceptable toxicant concentration (MATC) of 0.45 ug/L. The MATC is calculated as the geometric mean of the lowest observed effect concentration (LOEC) of 0.64 ug/L and the no observed effect concentration (NOEC) of 0.31 ug/L, as determined in a 21 day toxicity study with the water flea, Daphnia magna. Threshold values (LOEC and NOEC) are from USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111311	Region 9
Santa Margarita River (Upper)

Pollutant:	Endrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111311, Endrin Region 9      Santa Margarita River (Upper)
LOE ID:	137080
Pollutant:	Endrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Endrin .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111311, Endrin Region 9      Santa Margarita River (Upper)
LOE ID:	137152
Pollutant:	Endrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Endrin .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111352	Region 9
Santa Margarita River (Upper)

Pollutant:	Esfenvalerate/Fenvalerate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOEs 76580 and 76581 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:	LOEs 76580 and 76581 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	137445
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2014-11-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142394
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142479
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	137322
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142526
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2014-05-14 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	137269
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2014-11-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142542
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	227730
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Esfenvalerate.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	227746
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Esfenvalerate.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142405
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142342
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Esfenvalerate
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2014-05-14 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111352, Esfenvalerate/Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	137457
Pollutant:	Esfenvalerate/Fenvalerate
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111340	Region 9
Santa Margarita River (Upper)

Pollutant:	Ethoprop
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 19 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 19 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111340, Ethoprop Region 9      Santa Margarita River (Upper)
LOE ID:	142347
Pollutant:	Ethoprop
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ethoprop.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111340, Ethoprop Region 9      Santa Margarita River (Upper)
LOE ID:	142413
Pollutant:	Ethoprop
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Ethoprop.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111340, Ethoprop Region 9      Santa Margarita River (Upper)
LOE ID:	142349
Pollutant:	Ethoprop
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ethoprop.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111340, Ethoprop Region 9      Santa Margarita River (Upper)
LOE ID:	142345
Pollutant:	Ethoprop
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Ethoprop.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111338	Region 9
Santa Margarita River (Upper)

Pollutant:	Ethyl p-nitrophenyl (EPN)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111338, Ethyl p-nitrophenyl (EPN) Region 9      Santa Margarita River (Upper)
LOE ID:	142377
Pollutant:	Ethyl p-nitrophenyl (EPN)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for EPN.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for EPN is the LC50 of 6.8 ug/L for Gammarus fasciatus (Scud) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111338, Ethyl p-nitrophenyl (EPN) Region 9      Santa Margarita River (Upper)
LOE ID:	142375
Pollutant:	Ethyl p-nitrophenyl (EPN)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for EPN.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for EPN is the LC50 of 6.8 ug/L for Gammarus fasciatus (Scud) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111350	Region 9
Santa Margarita River (Upper)

Pollutant:	Fenpropathrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 18 samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 18 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	137448
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	137359
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2012-10-16 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142656
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142723
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142795
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142737
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	137498
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2012-10-16 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142847
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	142759
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	227688
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Fenpropathrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	227689
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Fenpropathrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111350, Fenpropathrin Region 9      Santa Margarita River (Upper)
LOE ID:	137470
Pollutant:	Fenpropathrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111296	Region 9
Santa Margarita River (Upper)

Pollutant:	Fenvalerate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111296, Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142833
Pollutant:	Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenvalerate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111296, Fenvalerate Region 9      Santa Margarita River (Upper)
LOE ID:	142584
Pollutant:	Fenvalerate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenvalerate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference:	OPP Pesticide Ecotoxicity Database.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2011-02-17 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111313	Region 9
Santa Margarita River (Upper)

Pollutant:	Lead
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Fourteen lines of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of the 39 samples exceed the water quality threshold for the MUN beneficial use. Zero of two sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 41 samples exceed the threshold for the WARM/COLD beneficial use, and zero of 39 samples exceed the threshold for the MUN beneficial use, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76595
Pollutant:	Lead
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76597
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved lead to protect aquatic life in freshwater. The dissolved lead criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143235
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76598
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Lead.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76605
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved lead to protect aquatic life in freshwater. The dissolved lead criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76596
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Lead to protect aquatic life in freshwater. The dissolved Lead criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76604
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Lead.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for Lead is 0.015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	76594
Pollutant:	Lead
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143083
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143335
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	142982
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143309
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143152
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	142902
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143296
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	137668
Pollutant:	Lead
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Lead .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143114
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2014-05-14 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143375
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143184
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143424
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	142901
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143267
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Maximum Contaminant Level for lead is .015 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143211
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	137803
Pollutant:	Lead
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Lead .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111313, Lead Region 9      Santa Margarita River (Upper)
LOE ID:	143167
Pollutant:	Lead
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition

DECISION ID	111314	Region 9
Santa Margarita River (Upper)

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111314, Lindane/gamma Hexachlorocyclohexane (gamma-HCH) Region 9      Santa Margarita River (Upper)
LOE ID:	137654
Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for HCH, gamma- .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111314, Lindane/gamma Hexachlorocyclohexane (gamma-HCH) Region 9      Santa Margarita River (Upper)
LOE ID:	137284
Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for HCH, gamma- .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111315	Region 9
Santa Margarita River (Upper)

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold for the WARM/COLD beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 28 samples exceed the water quality threshold for the WARM/COLD beneficial use, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	76611
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	8
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Malathion.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	220983
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Malathion.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	220982
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Malathion.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-06-05 and 2018-06-13
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	143194
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Malathion.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for malathion is 500 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	143176
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Malathion.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for malathion is 500 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	77903
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Malathion.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Public Health (CDPH) archived advisory level criteria for malathion in drinking water is 160.0 ug/L.
Guideline Reference:	2011 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	77907
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Malathion.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111315, Malathion Region 9      Santa Margarita River (Upper)
LOE ID:	77904
Pollutant:	Malathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	8
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Malathion.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Department of Public Health (CDPH) archived advisory level criteria for malathion in drinking water is 160.0 ug/L.
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/10/2006-5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.

DECISION ID	128182	Region 9
Santa Margarita River (Upper)

Pollutant:	Mercury
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 128182, Mercury Region 9      Santa Margarita River (Upper)
LOE ID:	143127
Pollutant:	Mercury
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mercury. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 128182, Mercury Region 9      Santa Margarita River (Upper)
LOE ID:	143438
Pollutant:	Mercury
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Mercury. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 128182, Mercury Region 9      Santa Margarita River (Upper)
LOE ID:	143417
Pollutant:	Mercury
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Mercury.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 128182, Mercury Region 9      Santa Margarita River (Upper)
LOE ID:	143434
Pollutant:	Mercury
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Mercury.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111335	Region 9
Santa Margarita River (Upper)

Pollutant:	Methiocarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 111335, Methiocarb Region 9      Santa Margarita River (Upper)
LOE ID:	143160
Pollutant:	Methiocarb
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Methiocarb. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111335, Methiocarb Region 9      Santa Margarita River (Upper)
LOE ID:	143146
Pollutant:	Methiocarb
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Methiocarb. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111343	Region 9
Santa Margarita River (Upper)

Pollutant:	Naled
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111343, Naled Region 9      Santa Margarita River (Upper)
LOE ID:	143580
Pollutant:	Naled
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	14
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Naled.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111343, Naled Region 9      Santa Margarita River (Upper)
LOE ID:	143148
Pollutant:	Naled
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Naled. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111343, Naled Region 9      Santa Margarita River (Upper)
LOE ID:	143599
Pollutant:	Naled
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Naled. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111343, Naled Region 9      Santa Margarita River (Upper)
LOE ID:	143403
Pollutant:	Naled
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	14
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Naled.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111317	Region 9
Santa Margarita River (Upper)

Pollutant:	Nickel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold for the WARM/COLD beneficial use, and zero of the 28 samples exceed the water quality threshold for the MUN beneficial use. Zero of one sediment sample exceeds the water quality threshold for sediment; this sample size is sufficient to determine beneficial use support with the power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 28 samples exceed the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76491
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76620
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76621
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76618
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76617
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	77859
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	76619
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143594
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143767
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143550
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	138437
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Nickel .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143701
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143507
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143498
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143551
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	138158
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Nickel .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143617
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143524
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143669
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143575
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143464
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143483
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143651
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143677
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111317, Nickel Region 9      Santa Margarita River (Upper)
LOE ID:	143495
Pollutant:	Nickel
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nickel.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111318	Region 9
Santa Margarita River (Upper)

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	143466
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	143444
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	143557
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Not Recorded
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	77861
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	76493
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/13/2003-9/4/2003.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111318, Nitrate/Nitrite (Nitrite + Nitrate as N) Region 9      Santa Margarita River (Upper)
LOE ID:	76492
Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan

DECISION ID	127720	Region 9
Santa Margarita River (Upper)

Pollutant:	Nitrogen, Nitrite
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Zero of the 35 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 35 samples exceed the water quality threshold and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	76495
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Nitrite as N.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-9/5/2003.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	144055
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrite as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	144015
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nitrite as N.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	144051
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nitrite as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	76497
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Nitrite as N.
Data Reference:	Data for Metals, Nutrients, and Inorganics from the County of San Diego Sandia Creek and Santa Margarita River, 2004-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River upstream of Stone Creek - 902SMRGorge]
Temporal Representation:	Data was collected over the time period 12/6/2007-5/14/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the CRG Marine Laboratories and COSD Santa Margarita Mass Loading Report.
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	143997
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Nitrite as N.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	76496
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrite as N.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 127720, Nitrogen, Nitrite Region 9      Santa Margarita River (Upper)
LOE ID:	77866
Pollutant:	Nitrogen, Nitrite
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrite as N.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

DECISION ID	111319	Region 9
Santa Margarita River (Upper)

Pollutant:	Oxamyl (Vydate)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111319, Oxamyl (Vydate) Region 9      Santa Margarita River (Upper)
LOE ID:	144572
Pollutant:	Oxamyl (Vydate)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Oxamyl.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The California Maximum Contaminant Level for Oxamyl is 50 ug/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111320	Region 9
Santa Margarita River (Upper)

Pollutant:	Oxygen, Dissolved
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	76498
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Oxygen, Dissolved.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan, San Diego Basin, Warm Water Habitat Objective, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration for warm water habitats shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144675
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-10 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144455
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 6.0 mg/l in inland surface waters with the COLD beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144626
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144481
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144457
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	11
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 6.0 mg/l in inland surface waters with the COLD beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-10 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144428
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 6.0 mg/l in inland surface waters with the COLD beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144405
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 6.0 mg/l in inland surface waters with the COLD beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144651
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 6.0 mg/l in inland surface waters with the COLD beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144761
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	76499
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Oxygen, Dissolved.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan, San Diego Basin, Cold Water Habitat Objective, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 8.0 mg/l at any time.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111320, Oxygen, Dissolved Region 9      Santa Margarita River (Upper)
LOE ID:	144624
Pollutant:	Oxygen, Dissolved
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	111321	Region 9
Santa Margarita River (Upper)

Pollutant:	Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 17 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 17 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111321, Parathion Region 9      Santa Margarita River (Upper)
LOE ID:	144894
Pollutant:	Parathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111321, Parathion Region 9      Santa Margarita River (Upper)
LOE ID:	144981
Pollutant:	Parathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Parathion, Ethyl.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111321, Parathion Region 9      Santa Margarita River (Upper)
LOE ID:	144982
Pollutant:	Parathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Parathion, Ethyl.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111321, Parathion Region 9      Santa Margarita River (Upper)
LOE ID:	144962
Pollutant:	Parathion
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Ethyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference:	National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	130321	Region 9
Santa Margarita River (Upper)

Pollutant:	Permethrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	228022
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2008-12-16 to 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144986
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Permethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2017-05-25
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	228026
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP Stormwater data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Permethrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S00565)
Temporal Representation:	The samples were collected between the dates of 2009-05-06 and 2009-05-06
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	228027
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP Stormwater data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Permethrin.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S00565)
Temporal Representation:	The samples were collected between the dates of 2009-05-06 and 2009-05-06
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	138701
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	138630
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144808
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	138614
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	138483
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144827
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144901
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144862
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144807
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Permethrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2017-05-25
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144845
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	144880
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 130321, Permethrin Region 9      Santa Margarita River (Upper)
LOE ID:	227753
Pollutant:	Permethrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Permethrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2008-12-16 to 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.

DECISION ID	111341	Region 9
Santa Margarita River (Upper)

Pollutant:	Phorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 19 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 19 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145679
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145620
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145639
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The national academy of sciences no-adverse effect level in drinking water for phorate is 0.7 µg/L.
Guideline Reference:	National Academy of Sciences - Volume I Drinking Water and Health
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145600
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145680
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The national academy of sciences no-adverse effect level in drinking water for phorate is 0.7 µg/L.
Guideline Reference:	National Academy of Sciences - Volume I Drinking Water and Health
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111341, Phorate Region 9      Santa Margarita River (Upper)
LOE ID:	145755
Pollutant:	Phorate
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Phorate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111345	Region 9
Santa Margarita River (Upper)

Pollutant:	Phosmet
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111345, Phosmet Region 9      Santa Margarita River (Upper)
LOE ID:	145584
Pollutant:	Phosmet
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for phosmet is 140 µg/L.
Guideline Reference:	IRIS Reference Summary (Various Pollutants)
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111345, Phosmet Region 9      Santa Margarita River (Upper)
LOE ID:	145606
Pollutant:	Phosmet
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111345, Phosmet Region 9      Santa Margarita River (Upper)
LOE ID:	145604
Pollutant:	Phosmet
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111324	Region 9
Santa Margarita River (Upper)

Pollutant:	Selenium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 28 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	77872
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146529
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	76510
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	77871
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	76511
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L.
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146132
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146081
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146236
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146678
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146447
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146515
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146292
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146338
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146249
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146612
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146139
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146507
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146391
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146659
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146629
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146321
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146412
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146306
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California MCL for Selenium is .05 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146187
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146610
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146453
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146658
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	146649
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Selenium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111324, Selenium Region 9      Santa Margarita River (Upper)
LOE ID:	76512
Pollutant:	Selenium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan

DECISION ID	111325	Region 9
Santa Margarita River (Upper)

Pollutant:	Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146685
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146758
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146888
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146908
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	147005
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146780
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146663
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	76519
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Silver.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Silver to protect aquatic life in freshwater. The dissolved Silver criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	76518
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Silver.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Silver to protect aquatic life in freshwater. The dissolved Silver criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	76517
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Silver.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146718
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146383
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	147003
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146665
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111325, Silver Region 9      Santa Margarita River (Upper)
LOE ID:	146721
Pollutant:	Silver
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Silver.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111326	Region 9
Santa Margarita River (Upper)

Pollutant:	Simazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111326, Simazine Region 9      Santa Margarita River (Upper)
LOE ID:	146818
Pollutant:	Simazine
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Simazine.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111326, Simazine Region 9      Santa Margarita River (Upper)
LOE ID:	146820
Pollutant:	Simazine
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Simazine.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	127400	Region 9
Santa Margarita River (Upper)

Pollutant:	Specific Conductivity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Twenty-three of the 28 samples exceed the California Secondary MCL for Specific Conductivity. However, this is a recommended, not required value, which is lower than the upper and short-term acceptable ranges in Table 64449-B and is lower than the naturally occurring specific conductance in some southern California streams. This water quality threshold will be reevaluated for future Integrated Report cycles.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	146729
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 5 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	146975
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	146878
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	146988
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	76525
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Conductivity(Us).
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 127400, Specific Conductivity Region 9      Santa Margarita River (Upper)
LOE ID:	146972
Pollutant:	Specific Conductivity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	17
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 17 of 18 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-14 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111327	Region 9
Santa Margarita River (Upper)

Pollutant:	Sulfates
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	147128
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Sulfate.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Sulfate water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	76526
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Sulfate.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for sulfate is 250 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	76527
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Sulfate.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Sulfate objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 250 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	76528
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Sulfate.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Sulfate objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 250 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	146751
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Sulfate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Sulfate water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	147133
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	4
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 4 of 5 samples exceeded the water quality threshold for Sulfate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Sulfate water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111327, Sulfates Region 9      Santa Margarita River (Upper)
LOE ID:	147081
Pollutant:	Sulfates
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Sulfate.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Sulfate water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111333	Region 9
Santa Margarita River (Upper)

Pollutant:	Surfactants (MBAS)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111333, Surfactants (MBAS) Region 9      Santa Margarita River (Upper)
LOE ID:	143340
Pollutant:	Surfactants (MBAS)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for MBAS.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for MBAS is 0.5 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111333, Surfactants (MBAS) Region 9      Santa Margarita River (Upper)
LOE ID:	143380
Pollutant:	Surfactants (MBAS)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for MBAS.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for MBAS is 0.5 mg/L (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111328	Region 9
Santa Margarita River (Upper)

Pollutant:	Terbufos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111328, Terbufos Region 9      Santa Margarita River (Upper)
LOE ID:	147223
Pollutant:	Terbufos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Terbufos.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The USEPA drinking water health advisory for terbufos is 0.4 µg/L.
Guideline Reference:	2018 Edition of the Drinking Water Standards and Health Advisories
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2017-05-25 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111328, Terbufos Region 9      Santa Margarita River (Upper)
LOE ID:	147200
Pollutant:	Terbufos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111328, Terbufos Region 9      Santa Margarita River (Upper)
LOE ID:	147199
Pollutant:	Terbufos
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Terbufos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Terbufos is the USEPA Aquatic Life Benchmark of 0.03 ug/L for a invertebrate (acute).
Guideline Reference:	OPP Aquatic Life Benchmarks
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2017-05-25 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111329	Region 9
Santa Margarita River (Upper)

Pollutant:	Thallium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111329, Thallium Region 9      Santa Margarita River (Upper)
LOE ID:	147275
Pollutant:	Thallium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Thallium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The thallium criterion for the protection of human health from the consumption of water and organisms is 1.7 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111329, Thallium Region 9      Santa Margarita River (Upper)
LOE ID:	147272
Pollutant:	Thallium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Thallium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The thallium criterion for the protection of human health from the consumption of water and organisms is 1.7 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111329, Thallium Region 9      Santa Margarita River (Upper)
LOE ID:	147252
Pollutant:	Thallium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Thallium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The thallium criterion for the protection of human health from the consumption of water and organisms is 1.7 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111329, Thallium Region 9      Santa Margarita River (Upper)
LOE ID:	147226
Pollutant:	Thallium
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Thallium.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The thallium criterion for the protection of human health from the consumption of water and organisms is 1.7 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2014-09-11 and 2015-05-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	127531	Region 9
Santa Margarita River (Upper)

Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 127531, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) Region 9      Santa Margarita River (Upper)
LOE ID:	139128
Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 127531, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) Region 9      Santa Margarita River (Upper)
LOE ID:	139049
Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan

DECISION ID	111332	Region 9
Santa Margarita River (Upper)

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Nine lines of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of the 41 samples exceed the water quality threshold for the MUN beneficial use. Zero of two sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 41 samples exceeded the threshold, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148144
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	147875
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148077
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148173
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	139363
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Zinc .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148176
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148069
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148183
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148147
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148178
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148164
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	139318
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Zinc .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	147924
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76523
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego NDPES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148006
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148177
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148180
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148182
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Title 22 of the California Code of Regulations which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	148186
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76521
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76522
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Zinc.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76515
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:	The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	77869
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	State Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River - 902SMR-MLS-2]
Temporal Representation:	Data was collected on a single day 12/16/2008.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was used.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76513
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76514
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference:	Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76520
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference:	Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111332, Zinc Region 9      Santa Margarita River (Upper)
LOE ID:	76516
Pollutant:	Zinc
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	13
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego DWM data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Zinc.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road), Santa Margarita River @ SDSU Ecological Reserve Entrance]
Temporal Representation:	Data was collected over the time period 5/12/2003 - 5/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.

DECISION ID	111322	Region 9
Santa Margarita River (Upper)

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line of evidence is necessary to assess listing status. Six line(s) of evidence are available in the administrative record to assess this pollutant. Zero of the 28 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 28 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145451
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145445
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145320
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-14 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145409
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145694
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145732
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145696
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 18 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-14 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	76508
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for pH.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	76509
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for pH.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145154
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145255
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111322, pH Region 9      Santa Margarita River (Upper)
LOE ID:	145459
Pollutant:	pH
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	126468	Region 9
Santa Margarita River (Upper)

Pollutant:	Benthic Community Effects
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. 13 line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. Four of 27 benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold from the 2020 Cycle. One exceedance was not included in the four as insufficient BMI were collected to use the CSCI score. These data indicate that the waterbody is likely impaired for Benthic Community Effects. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing Benthic Community Effects in this waterbody segment on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of 27 benthic-macroinvertebrate bioassessment samples from the 2020 cycle had CSCI scores below 0.79. Therefore, this water body is exceeding the water quality threshold for the protection of the WARM and/or COLD beneficial use. 4. Pursuant to section 3.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	140693
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2013-02-20 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	145569
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	146025
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	145817
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2017-05-25
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	146002
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	146019
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	18
Number of Exceedances:	4
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 4 of 18 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	146300
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 2 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 5 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	146230
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 11 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Data for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	143963
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	144064
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	143945
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-06 and 2017-07-06
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	144023
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	10
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 10 of 17 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-05-31
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	143812
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	80832
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	12
Number of Exceedances:	2
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Twelve samples were taken at three stations in the Santa Margarita River above De Luz Creek. Two samples had CSCI scores below the 0.79 threshold, therefore exceeding the water quality objective for the aquatic life beneficial use.
Data Reference:	Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
	Region 9 CSCI Scores & Water Body Information
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	The samples were collected at the following stations: 902SMR-TWAS-1, 902S00565, and 902SMR-WGR
Temporal Representation:	The samples were collected from 2003 to 2007.
Environmental Conditions:
QAPP Information:	Data collected following SWAMP QA protocols for the RWB9 Status Sampling 2007 and 2008 water quality monitoring project and the County of San Diego NPDES MS4 Copermittees Receiving Waters Monitoring and Reporting Program
QAPP Information Reference(s):	e-mail clarifying QAPP information
QAPP Information Reference(s):	Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	7407
Pollutant:	Phosphorus
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	4
Data and Information Type:	Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality:	All four samples collected exceeded the total phosphorus water quality objective. Samples were collected between January 2003 and September 2003 for the SWAMP program.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters.
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SMSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:	The first two sampling events occurred between storm events and high base flow respectively. The third and fourth occurred during declining and minimum base flow respectively.
QAPP Information:	Puckett, M. 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program ("SWAMP"). California Department of Fish and Game, Monterey, CA.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	21194
Pollutant:	Total Nitrogen as N
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality:	Two of the four samples collected at Santa Margarita River on January 2003, April 2003, May 2003, and September 2003 show excessive nitrogen concentrations. (SWAMP, 2007).
Data Reference:	Monitoring data for Region 9
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:	The first two sampling events occurred between storm events and high base flow respectively. The third and fourth occurred during declining and minimum base flow respectively.
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):	2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	24978
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	3
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Selenastrum capricornutum- Six samples were collected and none showed significant toxicity levels (SL) as determined by the Selenastrum capricornutum growth test. Ceriodaphnia dubia- Six samples were collected and two samples show significant toxicity levels (SL) as determined by the Ceriodaphnia dubia survival/reproductive. Hyalella azteca- Six samples were collected and one sample show significant toxicity levels (SL) as determined by the Hyalella azteca growth/survival test. Samples were collected November 2001 through February 2006.
Data Reference:	San Diego Stormwater Copermittees Jurisdiction Urban Runoff Managment Program. Final Report. Baseline Long Term Effectiveness Assessment
	Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration (U.S. EPA, 2002).
Guideline Reference:	Water Quality Control Plan for the San Diego Basin
Spatial Representation:	Samples were collected at the monitoring stations Santa Margarita 1 located on the main stem of the Santa Margarita River.
Temporal Representation:	Samples were collected on the following dates: January 14-15, April 15-16, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	21402
Pollutant:	Toxicity
LOE Subgroup:	Toxicity
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	2
Data and Information Type:	Ambient toxicity testing (chronic)
Data Used to Assess Water Quality:	Four samples were collected at Santa Margarita 1 station 902SSMR1 from January to September 2003, they showed significant toxicity levels (SL) in the following test: Selenastrum algae growth test - Two of the four samples. Ceriodaphnia dubia survival and reproduction. No toxicity was observed.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference:	Monitoring data for Region 9
Spatial Representation:	One sampling site was used in this line of evidence. Santa Margarita 1 (902SSMR1 lat/long: 33.47404/-117.14148).
Temporal Representation:	Samples were collected on the following dates: January 15, April 16, May 14, and September 9, 2003.
Environmental Conditions:
QAPP Information:	Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215823
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	6
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902USM828 to determine beneficial use support and the results are as follows: 0 of 6 samples exceeded the threshold. CSCI scores were from 0.8742 to 0.9691 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902USM828
Temporal Representation:	Samples were collected from 5/29/2013 to 5/30/2018.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215829
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	1
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902FB1xxx to determine beneficial use support and the results are as follows: 1 of 3 samples exceeded the threshold. CSCI scores were from 0.2219 to 0.9141 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902FB1xxx
Temporal Representation:	Samples were collected from 5/2/2017 to 6/6/2017.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215835
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902SMRWGR to determine beneficial use support and the results are as follows: 0 of 2 samples exceeded the threshold. CSCI scores were from 0.8585 to 0.9832 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902SMRWGR
Temporal Representation:	Samples were collected from 2013 to 2015.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215843
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902S04661 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.94156856 to 0.94156856 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902S04661
Temporal Representation:	Samples were collected from 7/16/2014 to 7/16/2014.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215834
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902RB1xxx to determine beneficial use support and the results are as follows: 0 of 2 samples exceeded the threshold. CSCI scores were from 0.8825 to 0.9041 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902RB1xxx
Temporal Representation:	Samples were collected from 7/13/2017 to 6/8/2017.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215842
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902M18893 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.8676 to 0.8676 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902M18893
Temporal Representation:	Samples were collected from 5/18/2017 to 5/18/2017.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215844
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902S05173 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.8037 to 0.8037 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902S05173
Temporal Representation:	Samples were collected from 5/17/2011 to 5/17/2011.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215851
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902SMR_SC to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.8933 to 0.8933 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902SMR_SC
Temporal Representation:	Samples were collected from 2011 to 2011.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215853
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902S02357 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.8338 to 0.8338 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902S02357
Temporal Representation:	Samples were collected from 5/25/2010 to 5/25/2010.
Environmental Conditions:
QAPP Information:	Data collected following SWAMP QA protocols.
QAPP Information Reference(s):	Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215827
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	2
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902MWD1xx to determine beneficial use support and the results are as follows: 2 of 3 samples exceeded the threshold. CSCI scores were from 0.6311 to 0.8055 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902MWD1xx
Temporal Representation:	Samples were collected from 6/13/2017 to 7/18/2017.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215852
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for SMC33179 to determine beneficial use support and the results are as follows: 0 of 1 samples exceeded the threshold. CSCI scores were from 0.98101528 to 0.98101528 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station SMC33179
Temporal Representation:	Samples were collected from 6/11/2013 to 6/11/2013.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215828
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902SMRDRx to determine beneficial use support and the results are as follows: 0 of 3 samples exceeded the threshold. CSCI scores were from 0.797 to 0.8532 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902SMRDRx
Temporal Representation:	Samples were collected from 2011 to 2015.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 126468, Benthic Community Effects Region 9      Santa Margarita River (Upper)
LOE ID:	215833
Pollutant:	Benthic-Macroinvertebrate Bioassessments
LOE Subgroup:	Population/Community Degradation
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	2
Data and Information Type:	Benthic macroinvertebrate surveys
Data Used to Assess Water Quality:	Water Board staff assessed data for 902GG1xxx to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the threshold. CSCI scores were from 0.6795 to 0.7279 .
Data Reference:	California Stream Condition Index Scores for the 2020 Integrated Report
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference:	Bioassessment in complex environments: designing an index for consistent meaning in different settings
Spatial Representation:	Samples were collected from station 902GG1xxx
Temporal Representation:	Samples were collected from 5/24/2017 to 6/15/2017.
Environmental Conditions:
QAPP Information:	The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	111336	Region 9
Santa Margarita River (Upper)

Pollutant:	Bifenthrin
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Five lines of evidence are available in the administrative record to assess this pollutant. Four of five samples exceed the water quality threshold in water. Zero of zero samples exceed the quality threshold in sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of five samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. LOEs 76584 and 76585 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:	LOEs 76584 and 76585 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	135947
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	135854
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140493
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140491
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	227887
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	227757
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140693
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2013-02-20 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140656
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2013-02-20 and 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140708
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2016-05-18 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140642
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2014-05-14 and 2014-05-14
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	135968
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140507
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2014-05-14 and 2014-05-14
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140658
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140573
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2016-10-25
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	140563
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Bifenthrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2016-05-18 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111336, Bifenthrin Region 9      Santa Margarita River (Upper)
LOE ID:	135746
Pollutant:	Bifenthrin
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111348	Region 9
Santa Margarita River (Upper)

Pollutant:	Cyhalothrin, Lambda
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Two of two samples exceed the water quality threshold in water. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of two samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. LOEs 76550 and 76557 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:	LOEs 76550 and 76557 were removed from this decision and retired because the threshold changed, but the data did not have enough information to be reassessed.
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	227703
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	142909
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	136660
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	142997
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	143061
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2016-05-18 and 2016-05-18
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	143025
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	227915
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	136421
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Date for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	142963
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2016-05-18 and 2016-05-18
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	136933
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	142926
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	143108
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 11 samples were collected, 11 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	143107
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Date for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111348, Cyhalothrin, Lambda Region 9      Santa Margarita River (Upper)
LOE ID:	136662
Pollutant:	Cyhalothrin, Lambda
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda-. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Date for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load

DECISION ID	111334	Region 9
Santa Margarita River (Upper)

Pollutant:	Pyrethroids
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List. Seven lines of evidence are available in the administrative record to assess this pollutant. Seven of eight samples exceed the water quality threshold in water. Zero of five samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Seven of eight samples exceed the water quality threshold in water, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	227992
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	138822
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference:	Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	138951
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference:	Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146092
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 2 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 5 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146230
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 11 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Data for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146180
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146318
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	0
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173).
Temporal Representation:	Date for this waterbody was collected over the date range 2011-05-17 to 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146300
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	2
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 2 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 5 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828).
Temporal Representation:	Data for this waterbody was collected over the date range 2013-05-29 to 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	146298
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	3
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 11 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2).
Temporal Representation:	Data for this waterbody was collected over the date range 2011-02-17 to 2017-02-19
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	138790
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	4
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference:	Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): SMR-MLS-2.
Temporal Representation:	Data for this waterbody were collected over the date range 2010-10-27 to 2016-11-01
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	138953
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Sediment
Matrix:	Sediment
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit equivalent. A toxic unit equivalent is equal to the sum of; Bifenthrin, Cyfluthrin, Cypermethrin, Lambda-Cyhalothrin, and Permethrin, each having their reported concentration divided their respective evaluation guideline prior to being summed. If this results in a value greater than one, the sample day is considered to be in exceedance of the water quality standard. (Department of Fish and Game Aquatic Life Criteria for Pyrethroid Insecticides, 2000)
Guideline Reference:	Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference:	Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference:	Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference:	Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference:	Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.
Spatial Representation:	Data were collected from 1 station(s). Station Code(s): 902USM828.
Temporal Representation:	Data for this waterbody were collected over the date range 2013-05-29 to 2013-05-29
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	228008
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP Stormwater data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S00565)
Temporal Representation:	The samples were collected between the dates of 2009-05-06 and 2009-05-06
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	227994
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference:	Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2008-12-16 and 2008-12-16
Environmental Conditions:
QAPP Information:	The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s):	Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
Line of Evidence (LOE) for Decision ID 111334, Pyrethroids Region 9      Santa Margarita River (Upper)
LOE ID:	228005
Pollutant:	Pyrethroids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP Stormwater data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference:	Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
Spatial Representation:	The samples were collected at 1 monitoring site (902S00565)
Temporal Representation:	The samples were collected between the dates of 2009-05-06 and 2009-05-06
Environmental Conditions:
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan

DECISION ID	125489	Region 9
Santa Margarita River (Upper)

Pollutant:	Total Dissolved Solids
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Eighteen of the 25 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Eighteen of 25 samples exceed the Basin Plan objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	215111
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	4
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for total dissolved solids.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Dissolved Solids objective in this HSA is 750 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monioring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 9/6/2012 and 5/2/2013
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	76501
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Dissolved Solids.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Dissolved Solids objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 750 mg/L.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	215198
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for total dissolved solids.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Dissolved Solids objective in this HSA is 750 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monioring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 5/29/2013 and 5/30/2018
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	76500
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Dissolved Solids.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	The California Secondary MCL for Dissolved Solids is 500 mg/L (Title 22 California Code of Regulations).
Guideline Reference:	Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	215112
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	14
Number of Exceedances:	13
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 13 of 14 samples exceeded the water quality threshold for total dissolved solids.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Total Dissolved Solids objective in this HSA is 750 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monioring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 9/15/2010 and 5/31/2017
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 125489, Total Dissolved Solids Region 9      Santa Margarita River (Upper)
LOE ID:	215113
Pollutant:	Total Dissolved Solids
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for total dissolved solids.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Total Dissolved Solids objective in this HSA is 750 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monioring site (902S05173)
Temporal Representation:	The samples were collected on 5/17/2011
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.

DECISION ID	111331	Region 9
Santa Margarita River (Upper)

Pollutant:	Turbidity
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2033
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Seventeen lines of evidence are available in the administrative record to assess this pollutant. Five of the 26 samples exceed the MUN beneficial use threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of the 26 samples exceed the [OBJECTIVE/GUIDELINE/CRITERIA] and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147711
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147443
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147738
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	17
Number of Exceedances:	4
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 4 of 17 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147592
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147798
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 17 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147521
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	17
Number of Exceedances:	3
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 3 of 17 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-MLS-2)
Temporal Representation:	The samples were collected between the dates of 2010-09-15 and 2017-09-26
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147577
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147667
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	2
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147975
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147737
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147799
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed RWB9 So. CA Stormwater Monitoring Coalition data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902S05173)
Temporal Representation:	The samples were collected between the dates of 2011-05-17 and 2011-05-17
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2009. Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions. .
QAPP Information Reference(s):	Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147421
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	5
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (902USM828)
Temporal Representation:	The samples were collected between the dates of 2013-05-29 and 2018-05-30
Environmental Conditions:
QAPP Information:	Riverside County. 2018. Volume II: Quality Assurance Project Plan.
QAPP Information Reference(s):	Volume II: Quality Assurance Project Plan
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	76505
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Turbidity(NTU).
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Turbidity(NTU) objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 20 NTU.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	76504
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Turbidity(NTU).
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Turbidity(NTU) objective for the protection of aquatic life according to Table 3-2 for Santa Margarita River (Upper) within the Santa Margarita Hydrologic Unit is 20 NTU.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147595
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	148059
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Warm Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMR-WGR)
Temporal Representation:	The samples were collected between the dates of 2017-07-07 and 2017-07-07
Environmental Conditions:
QAPP Information:	County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s):	Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s):	Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s):	Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
Line of Evidence (LOE) for Decision ID 111331, Turbidity Region 9      Santa Margarita River (Upper)
LOE ID:	147437
Pollutant:	Turbidity
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	2
Number of Exceedances:	1
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SMC Regional Watershed Monitoring data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Turbidity.
Data Reference:	Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference:	Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	The samples were collected at 1 monitoring site (SMC04661)
Temporal Representation:	The samples were collected between the dates of 2011-07-18 and 2014-07-16
Environmental Conditions:
QAPP Information:	Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s):	Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s):	Bioassessment Survey of the Stormwater Monitoring Coalition

DECISION ID	72806	Region 9
Santa Margarita River (Upper)

Pollutant:	Metals
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objectives for the multiple metal pollutants. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceed the water quality objectives for the multiple metal pollutants and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 72806, Metals Region 9      Santa Margarita River (Upper)
LOE ID:	26399
Pollutant:	Metals
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Dissolved
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	44
Number of Exceedances:	0
Data and Information Type:	Highest quality fixed-station P/C (conventional plus toxicants)
Data Used to Assess Water Quality:	Fouty-four samples were collected at Santa Margarita Creek station 902SMSMR1 during the months of January 2003, April 2003, May 2003, and September 2003, for metals analyses. None of the 44 samples show excessive concentrations.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	The Maximum Contaminant Level (MCL) for aluminum is 1. mg /l (ppb). Water Quality Control for the San Diego Basin. 2007. The dissolved chronic criterion for the following metals applies: arsenic 150 µg/l (ppb), cadmium 2.2 µg/l (ppb), copper 9.0 µg/l (ppb), selenium 5.0 µg/l (ppb), zinc 120 µg/l (ppb), chromium 11 µg/l (ppb), manganese 0.05 mg/l, nickel 52 µg/l (ppb), lead 2.5 µg/l (ppb), and silver 3.4µg/l (ppb). California Toxics Rule. 2007.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Water samples were collected at Santa Margarita Creek station 902SMSMR1; (Latitude 33.4741, Longitude -117.1414).
Temporal Representation:	Water samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:
QAPP Information:	Quality control for chemical analysis portion of this study was conducted in accordance with the California Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID	81796	Region 9
Santa Margarita River (Upper)

Pollutant:	Nitrogen, ammonia (Total Ammonia)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the four samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the four samples exceed the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to [SECTION 3.11/4.11] of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 81796, Nitrogen, ammonia (Total Ammonia) Region 9      Santa Margarita River (Upper)
LOE ID:	76571
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Total
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Ammonia As N, Total.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 5/6/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 81796, Nitrogen, ammonia (Total Ammonia) Region 9      Santa Margarita River (Upper)
LOE ID:	76572
Pollutant:	Nitrogen, ammonia (Total Ammonia)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	3
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed County of San Diego data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Ammonia As N, Total.
Data Reference:	Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."
Guideline Reference:	2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 2 monitoring sites [ Santa Margarita River @ SDSU Ecological Reserve Entrance, Santa Margarita River @ Sandia Creek Drive (one-half mile east of De Luz Road)]
Temporal Representation:	Data was collected over the time period 5/12/2003-9/4/2003.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s):	Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.

DECISION ID	76378	Region 9
Santa Margarita River (Upper)

Pollutant:	PAHs (Polycyclic Aromatic Hydrocarbons)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	The decision has not changed from the previous listing cycle. No new data were assessed for the current listing cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the 208 samples exceed the Basin Plan water quality objective for polycyclic aromatic hydrocarbons. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 208 samples exceed the Basin Plan water quality objective for polycyclic aromatic hydrocarbons and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 76378, PAHs (Polycyclic Aromatic Hydrocarbons) Region 9      Santa Margarita River (Upper)
LOE ID:	26400
Pollutant:	PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Not Recorded
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	208
Number of Exceedances:	0
Data and Information Type:	Highest quality fixed-station P/C (conventional plus toxicants)
Data Used to Assess Water Quality:	208 samples were collected at Santa Margarita Creek station 902SMSMR1 during the months of January 2003, April 2003, May 2003, and September 2003, for PAHs analyses. None of the 208 samples showed excessive concentrations.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCL 0.0002mg/l) specified in California Code of Regulations, Title 22, Table 64444-A of section 64444 (Organic Chemicals) which is incorporated by reference into this plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Water samples were collected at Santa Margarita Creek station 902SMSMR1; (Latitude 33.4741, Longitude -117.1414).
Temporal Representation:	Water samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:
QAPP Information:	Quality control for chemical analysis portion of this study was conducted in accordance with the California Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID	77778	Region 9
Santa Margarita River (Upper)

Pollutant:	PCBs (Polychlorinated biphenyls)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	The decision has not changed from the previous listing cycle. No new data were assessed for the current listing cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the 208 samples exceed the Basin Plan water quality objective for polychlorinated biphenyls. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 208 samples exceed the Basin Plan water quality objective for polychlorinated biphenyls and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 77778, PCBs (Polychlorinated biphenyls) Region 9      Santa Margarita River (Upper)
LOE ID:	26401
Pollutant:	PCBs (Polychlorinated biphenyls)
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	Not Recorded
Beneficial Use:	Municipal & Domestic Supply
Number of Samples:	208
Number of Exceedances:	0
Data and Information Type:	Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality:	208 samples were collected at Santa Margarita Creek station 902SMSMR1 during the months of January 2003, April 2003, May 2003, and September 2003, for PCBs analyses. None of the 208 samples showed excessive concentrations.
Data Reference:	Monitoring data for Region 9
SWAMP Data:	Non-SWAMP
Water Quality Objective/Criterion:	From the Basin Plan; waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCL 0.5 mg/l) specified in California Code of Regulations, Title 22, Table 64444-A of section 64444 (Organic Chemicals) which is incorporated by reference into this plan.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:
Guideline Reference:
Spatial Representation:	Water samples were collected at Santa Margarita Creek station 902SMSMR1; (Latitude 33.4741, Longitude -117.1414).
Temporal Representation:	Water samples were collected on January 2003, April 2003, May 2003, and September 2003.
Environmental Conditions:
QAPP Information:	Quality control for chemical analysis portion of this study was conducted in accordance with the California Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID	81184	Region 9
Santa Margarita River (Upper)

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant
Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One lines of evidence is available in the administrative record to assess this pollutant. Zero of the one sample exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the one sample exceed the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
State Board Review of Regional Board Conclusion and Recommendation:
State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 81184, Temperature, water Region 9      Santa Margarita River (Upper)
LOE ID:	76529
Pollutant:	Temperature, water
LOE Subgroup:	Pollutant-Water
Matrix:	Water
Fraction:	None
Beneficial Use:	Cold Freshwater Habitat
Number of Samples:	1
Number of Exceedances:	0
Data and Information Type:	PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality:	Water Board staff assessed SWAMP data for Santa Margarita River (Upper) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Water Temperature.
Data Reference:	RWB9 Stormwater Monitoring Council CY 2009
SWAMP Data:	SWAMP
Water Quality Objective/Criterion:	The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5°F above the natural receiving water temperature.
Objective/Criterion Reference:	Water Quality Control Plan for the San Diego Basin
Evaluation Guideline:	Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference:	Inland Fishes of California
Spatial Representation:	Data for this line of evidence for Santa Margarita River (Upper) was collected at 1 monitoring site [ Santa Margarita River ~0.3mi above Sandia Cr. Dr. - 902S00565]
Temporal Representation:	Data was collected on a single day 4/27/2009.
Environmental Conditions:	Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information:	The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):	Surface Water Ambient Monitoring Program Quality Assurance Program Plan