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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Del Puerto Creek (Stanislaus County)
Water Body ID: CAR5421003020210106050661
Water Body Type: River & Stream
 
DECISION ID
130536
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Dimethoate
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (TMDL required list)(2020)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
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 this pollutant for Warm Freshwater Habitat (WARM). Four of the 146 samples exceeded the guideline for WARM.

LOE 226629 has been replaced by LOE 226839 and LOE 226963 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for 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. Four of the 146 samples exceeded the guideline for WARM and this does not exceed 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 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 removed from the section 303(d) list because applicable water quality standards for the pollutant 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 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226963
 
Pollutant: Dimethoate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Dimethoate Water Quality Data from 2009-2010 from the Irrigated Lands Regulatory Program
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-01-25 and 2010-04-13
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226840
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 21 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226689
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226628
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 20 water samples were collected from Del Puerto Creek from June 2003 to February 2005 that were averaged using a 7-day average per section 6.1.5 of the Listing Policy resulting in 14 concentrations. Zero out of 14 averaged concentrations exceeded the maximum concentration of 4.3 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide... The evaluation guideline for dimethoate, 4.3 ug/L, is one-tenth of the median lethal concentration (LC50 = 43 ug/L) for Pteronarcys californica (Stonefly); USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Water samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Water samples were collected from Del Puerto Creek between June 2003 and February 2005 at intervals ranging from weekly to monthly.
Environmental Conditions:
QAPP Information: Data Quality: Good. Minimum requirements for the Surface Water Database are: Name of the sampling agency or organization Date that each sample was collected Date of each sample analysis County where samples were taken Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.) Name or description of water body sampled Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation Description of analytical QA/QC plan, or statement that no formal plan exists Additional optional requirements are included on DPR¿s webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226627
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 32 water samples were collected from Del Puerto Creek from July 2004 to August 2006. Zero out of 32 concentrations exceeded the maximum concentration of 4.3 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data:
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide... The evaluation guideline for dimethoate, 4.3 ug/L, is one-tenth of the median lethal concentration (LC50 = 43 ug/L) for Pteronarcys californica (Stonefly); USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Water samples were collected from Del Puerto Creek at Highway 33 and at Cox Road.
Temporal Representation: Water samples were collected from Del Puerto Creek monthly between June 2004 and August 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226511
 
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: Not Specified
Data Used to Assess Water Quality: Two water samples were collected from Del Puerto Creek under the Pesticide TMDL program, on 28 February 2006 and on 1 March 2006. None of the samples exceeded the Evaluation Guideline of 0.2 ug/L.

0 of 2 available concentrations exceeded the criterion (0.2 ug/L).
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 ug/L.
Guideline Reference: ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Water samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Water samples were collected from Del Puerto Creek on 28 February 2006 and on 1 March 2006.
Environmental Conditions:
QAPP Information: Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP prepared for the Pesticide TMDL program sampling.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226964
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and the results are as follows: 1 of the 8 samples exceeded the water quality threshold for Dimethoate. Although a total of 9 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 in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523).
Temporal Representation: Data for this waterbody was collected over the date range 2004-07-06 to 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226929
 
Pollutant: Dimethoate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130536, Dimethoate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226839
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 2 of 8 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Dimethoate Water Quality Data from 2009-2010 from the Irrigated Lands Regulatory Program
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2009-10-15 and 2010-08-10
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130559
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision: 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)(2020)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Expected TMDL Completion Date: 2027
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.

Five lines of evidence are available in the administrative record to assess this pollutant for Municipal and Domestic Supply (MUN). Seven of the 94 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for 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. Seven of the 94 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for MUN and this does not exceed 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 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 removed from the section 303(d) list because applicable water quality standards for the pollutant 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 130559, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226863
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L (California Code of Regulations, Title 22).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130559, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226732
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 72
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 4 of 72 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L (California Code of Regulations, Title 22).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-16 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130559, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226579
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 3 of 16 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate + nitrite (as N) is 10.0 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130559, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226435
 
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: 0 of 1 samples exceed the water quality objective for Nitrate + Nitrite (as N). The Nitrate + Nitrite (as N) MCL objective is 10 mg/L. The datum is reported as underneath the quantitation limit. This quantitation limit is less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The Nitrate + Nitrite (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at 542DPCDPC (Del Puerto Creek).
Temporal Representation: Samples collected on 6/18/2008.
Environmental Conditions:
QAPP Information: 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 130559, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226442
 
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: SWAMP data indicates that 0 of the sample results exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The U.S. EPA Primary Maximum Contaminant Level for nitrate + nitrite (as N) is 10,000 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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
130517
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Diazinon
Final Listing Decision: Delist from 303(d) list (being addressed by action other than TMDL)
Last Listing Cycle's Final Listing Decision: Delist from 303(d) list (being addressed by action other than TMDL)(2020)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; reason for recovery unspecified
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-2014-0041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of diazinon to this segment have been identified as offsite movement of diazinon from diazinon applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
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.

Sixteen lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM) and Municipal and Domestic Supply (MUN). Ten of 238 water samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM. Zero of the ten sediment samples exceeded the evaluation guideline for WARM. Zero of the ten water samples, with the fraction not reported, exceed the guideline for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for 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. Ten of 238 water samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM. Zero of the ten sediment samples exceeded the evaluation guideline for WARM. Zero of the ten water samples, with the fraction not reported, exceed the guideline for MUN. This does not exceed 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 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226539
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Two of the ten samples exceeded the evaluation guideline.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Criteria Continuous Concentration (four day average) for diazinon in freshwater is 0.05 ug/L.
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
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226540
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the ten samples exceeded the water quality objective.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The California Department of Public Health (CDPH) Notification Level for Diazinon is 1.2 ug/L.
Guideline Reference: Drinking Water Notification and Response Levels: An Overview
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226919
 
Pollutant: Diazinon
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226538
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 20 samples exceed the criterion for Diazinon.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater chronic criterion 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226784
 
Pollutant: Diazinon
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Diazinon. 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 objective 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 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon 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): 541XDPCCR.
Temporal Representation: Date for this waterbody were collected over the date range 2014-03-10 to 2014-03-10
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226782
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226677
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226642
 
Pollutant: Diazinon
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon 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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2013-07-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226639
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for diazinon, 1.1 ug/g, is one-tenth of the median lethal concentration for H. azteca(LC50; 11 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon 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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2013-09-09 to 2014-03-10
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226630
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 46
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 46 samples exceeded the water quality standard for Diazinon.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: 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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 3 monitoring site(s) (541STC523, 541XDPCCR, 541XDPCHW)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2015-09-15
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226493
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 48
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 54 Water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 48 4-day average concentrations and 54 1-hour average concentrations.5 of 48 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 5 of 54 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion 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
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226492
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 32 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 32 4-day average concentrations and 32 1-hour average concentrations.2 of 32 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 2 of 32 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion 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
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226491
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 2 water samples were collected from Del Puerto Creek from January through March 2006, representing 2 4-day average concentrations and 2 1-hour average concentrations.0 of 2 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 0 of 2 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion 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
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Two samples were collected. One sample was collected in February and one in March.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226490
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 4-day average concentrations and 19 1-hour average concentrations.0 of 19 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 0 of 19 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (biweekly and weekly) from March through August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226455
 
Pollutant: Diazinon
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 130517, Diazinon
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226487
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 3 4-day average concentrations and 19 1-hour average concentrations.0 of 3 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 ug/L. 0 of 19 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (hourly or daily) from February to March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
 
DECISION ID
130515
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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.

Sixteen lines of evidence are available in the administrative record to assess this pollutant. Eleven lines of evidence are available to assess for Warm Freshwater Habitat. Two lines of evidence are available to assess for Municipal and Domestic Supply. Two lines of evidence are available to assess for Commercial or recreational collection of fish, shellfish, or organisms. Four of the ten sediment samples exceed the guideline for Warm Freshwater Habitat. Fifty-seven of the 78 sediment toxicity samples, exceed the guideline for Warm Freshwater Habitat. Four of the eight water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for Municipal and Domestic Supply. Two of the two water samples, reported as a total concentration, exceed the criterion for Commercial or recreational collection of fish, shellfish, or organisms.

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. Four of the ten sediment samples exceed the guideline for Warm Freshwater Habitat. Fifty-seven of the 78 sediment toxicity samples, exceed the guideline for Warm Freshwater Habitat. Four of the eight water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for Municipal and Domestic Supply. Two of the two water samples, reported as a total concentration, exceed the criterion for Commercial or recreational collection of fish, shellfish, or organisms. 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: 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 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226915
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for DDE(p,p'). Although a total of 5 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541STC523).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226464
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty four samples were collected from Del Puerto Creek and analyzed for DDE, a metabolite of DDT, between January 2000 and August 2001. Data is not usable because it has high Reporting Limits and can not be determined if the 34 samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria DDE limit of 0.00059 ug/L based on a human health 10-6 carcinogenic risk for consumption of water and aquatic organisms.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a).Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000)Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) for DDE of less than 0.00059 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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: Samples were collected from Del Puerto Creek at Vineyard Ave. (tributary to San Joaquin River), Stanislaus County.
Temporal Representation: Samples were collected at weekly intervals within specific months (January and February in 2000; April - August in 2001).
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226610
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support.
The results of samples collected from the same site and on the same date were averaged before they were assessed. The 25 sample results reported represent 24 samples for assessment. Five of the 24 averaged sample results were detected at levels above reporting limits limit of 0.01 ug/L. Since the reporting limits were greater than the criterion for 19 samples, these were not assessed. One sample (of five averaged sample results) exceeded the CTR value of 0.00059 ug/L.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for DDE(p,p') and DDE(o,o') to protect human health from the consumption of water and organisms is 0.00059 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites: [five averaged sample results were collected from Del Puerto Creek @ Hwy 33 - 541STC523, and 19 samples were collected from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226674
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for DDE(p,p'). Although a total of 54 samples were collected, 52 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from consumption of organisms only is 0.00084 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226676
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for DDE(p,p'). Although a total of 54 samples were collected, 52 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDE(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226774
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 4 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226776
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130515, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
 
DECISION ID
130526
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Dieldrin
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Nine lines of evidence are available in the administrative record to assess pollutant for Warm Freshwater Habitat (WARM), Municipal and Domestic Supply (MUN), and Commercial or recreational collection of fish, shellfish, or organisms (COMM). Zero of the 80 water samples, reported as a total concentration or with the fraction not reported, exceed the criterion for WARM. Zero of the six sediment samples exceed the guideline for WARM. One of the one water samples exceed the criterion for MUN. Two of the eight water samples exceed the criterion for COMM.

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. Two of the eight water samples exceed the criterion for COMM 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 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226473
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-three samples were collected from Del Puerto Creek and based on a 30-day average, the samples reduced to Eight samples. These were analyzed for Dieldrin between June 1994 and August 2001. Two of the Eight water samples exceeded the CTR criteria for Dieldrin of 0.00014 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  National Water Quality Assessment database, San Joaquin and Tulare Basins data
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: - Sacramento/San Joaquin River Basin Plan for Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB 2007).- California Toxics Rule Criteria (USEPA, 2000):Criteria based on Human Health Protection (30-day average) with a Dieldrin limit of less than 0.00014 ug/L for water and fish consumption.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Ave. (tributary to San Joaquin River).
Temporal Representation: Samples were taken at weekly intervals within specific months (January and February in 2000; April - August in 2001).
Environmental Conditions:
QAPP Information: Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): National Field Manual for the Collection of Water-Quality Data, Techniques of Water-Resources Investigations, Book 9, Handbooks for Water-Resources Investigations
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226683
 
Pollutant: Dieldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226685
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Dieldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226686
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from consumption of organisms only is 0.00014 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226787
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 = 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226542
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Dieldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226543
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 1 sample exceeds the criterion for Dieldrin. Although twenty additional water sample results were available, the reporting limits were all higher than the evaluation guideline and, therefore, the results could not be quantified with the level of certainty required by the Listing Policy and could not be used in the assessment.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion for Dieldrin to protect human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule).
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226928
 
Pollutant: Dieldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dieldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130526, Dieldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226922
 
Pollutant: Dieldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dieldrin. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criteria for the protection of human health from the consumption of water and organisms is 0.00014 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130518
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Indicator Bacteria
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)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
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 4.2 of the Listing Policy. Under this section 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 for Water Contact Recreation (REC-1). Twenty-five of the 75 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1.

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. Twenty-five of the 75 samples, expressed as a Statistical Threshold Value, exceed the objective for REC-1 and this exceeds the allowable frequency listed in Table 4.2 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.

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 130518, Indicator Bacteria
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226457
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 144
Number of Exceedances: 60
 
Data and Information Type: Water column surveys (e.g. fecal coliform)
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 144 samples from November 2004 to November 2005. Sixty out of 144 samples exceeded the evaluation objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at six locations: Del Puerto Creek at Deer Creek Campground, Del Puerto Creek at Del Puerto Canyon Road Mile 13.6, Del Puerto Creek at Del Puerto Canyon Road Mile 3.9, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33 and Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Sampling occurred from July 2002 to November 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board¿s Quality Assurance Program Plan for the State of California¿s Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130518, Indicator Bacteria
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226456
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 52
Number of Exceedances: 32
 
Data and Information Type: Water column surveys (e.g. fecal coliform)
Data Used to Assess Water Quality: The Westside San Joaquin River Water Quality Coalition collected 52 samples from July 2004 to October 2006. Thirty-two out of the 52 samples collected exceeded the evaluation objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at two locations: Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: Monthly sampling occurred July 2004 to October 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130518, Indicator Bacteria
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226752
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 71
Number of Exceedances: 24
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Del Puerto Creek to determine beneficial use support and the results are as follows: 24 of the 71 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
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): 541XDPCCR
Temporal Representation: The samples were collected between the days of 2010-09-16 and 2018-02-13 .
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130518, Indicator Bacteria
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226958
 
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: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and the results are as follows: 1 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
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): 541STC523
Temporal Representation: The samples were collected between the days of 2010-12-20 and 2011-04-12 .
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130518, Indicator Bacteria
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226549
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 31
Number of Exceedances: 11
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 11 of 31 samples exceed the criterion for Escherichia coli.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended objective for single sample maximum allowable density of E. coli in freshwater designated beach areas is 235 MPN/100mL.
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/10/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130591
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Linuron
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)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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.

Four lines of evidence are available in the administrative record to assess pollutant. Nine of the nine samples exceed the evaluation guideline for Warm Freshwater Habitat.

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 nine samples exceed the evaluation guideline for Warm Freshwater Habitat 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 130591, Linuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226720
 
Pollutant: Linuron
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. Although a total of 56 samples were collected, 56 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 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130591, Linuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226967
 
Pollutant: Linuron
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Linuron. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Data for this waterbody was collected over the date range 2006-07-11 to 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130591, Linuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226947
 
Pollutant: Linuron
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. 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 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130591, Linuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226845
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and the results are as follows: 7 of the 7 samples exceeded the water quality threshold for Linuron. Although a total of 19 samples were collected, 12 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 in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2006-07-11 to 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130509
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Nickel
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)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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-one lines of evidence are available in the administrative record to assess this pollutant. Five of the five sediment samples exceed the objective for Warm Freshwater Habitat. Fifty-seven of the 78 sediment toxicity samples exceed the guideline for Warm Freshwater Habitat. Zero of the 51 water samples, reported as a dissolved concentration, exceeded the objective for Warm Freshwater Habitat. Zero of the four water samples, with the fraction not reported, exceeded the objective for Warm Freshwater Habitat. Zero of the 33 water samples, reported as a dissolved concentration, exceeded the criteria for Commercial or recreational collection of fish, shellfish, or organisms. Zero of the 33 water samples, reported as a total concentration, exceeded the criteria for Commercial or recreational collection of fish, shellfish, or organisms. Zero of the 37 water samples, reported as a dissolved concentration, exceeded the objective for Municipal and Domestic Supply. One of the 63 water samples, reported as a total concentration or with the fraction not reported, exceeded the objective for Municipal and Domestic Supply.

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 five sediment samples exceed the objective for Warm Freshwater Habitat. Fifty-seven of the 78 sediment toxicity samples exceed the guideline for Warm Freshwater Habitat. 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: 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 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226792
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Nickel from MacDonald et al., 2000a which states that the probable effect concentration for Nickel is 48.6 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226730
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226729
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226728
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226727
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 33 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226726
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226578
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 26
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 26 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nickel is 0.1 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226860
 
Pollutant: Nickel
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226862
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226861
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226577
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 AgWaiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The 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 metals criteria.
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 Del Puerto Creek was collected at 1 monitoring site [ Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/14/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226460
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved nickel
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved nickel levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)
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: Samples were collected from Del Puerto Creek at Vineyard Avenue
Temporal Representation: The samples were collected between November 29, 2000, and October 30, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130509, Nickel
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
 
DECISION ID
130535
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Salinity
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: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4.2 of the Listing Policy. Under section 4.2 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. Sixty-eight of the 175 available water sample results exceed the evaluation guidelines for the the Municipal & Domestic Supply beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification in favor of removing 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. Sixty-eight of 175 samples exceed the water quality objectives for electrical conductivity/specific conductivity and total dissolved solids (collectively ¿salinity¿) and this exceeds the allowable frequency listed in Table 4.2 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 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 removed from the section 303(d) list. The readily available data and information is sufficient 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 130535, Salinity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226546
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 34
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 15 of 34 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130535, Salinity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226506
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Ten samples were taken from Del Puerto Creek between 2000 and 2002. Six of the 10 samples exceed the California Secondary MCL for TDS in surface water.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard, Deer Creek, Highway 33, Del Puerto 3.9 and Del Puerto 13.6 in Stanislaus County.
Temporal Representation: Samples were collected between October 2000 and October 2002. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130535, Salinity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226505
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 28
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Twenty-eight samples were taken from Del Puerto Creek between 2004 and 2006. Seven of the twenty-eight samples exceed the California Secondary MCL for TDS in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130535, Salinity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226503
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 30
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty samples were taken from Del Puerto Creek between 2004 and 2006. Three of the thirty samples exceed the California Secondary MCL for EC in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130535, Salinity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226504
 
Pollutant: Salinity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 73
Number of Exceedances: 37
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Seventy-three samples were taken from Del Puerto Creek between 2000 and 2005. Thirty-seven of the seventy-three samples exceed the California Secondary MCL for EC in surface water.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL's) protective of MUN (CVRWQCB, 2007a).The secondary MCL's for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The 'recommended' concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard, Deer Creek, Highway 33, Del Puerto 3.9 and Del Puerto 13.6 in Stanislaus County.
Temporal Representation: Samples were collected between October 2000 and November 2005. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
130577
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Total Dissolved Solids
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)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
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 4.2 of the Listing Policy. Under this section 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. 93 of the 163 samples exceed the objective for Municipal & Domestic Supply.

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. 93 of the 163 samples exceed the objective for Municipal & Domestic Supply and this exceeds the allowable frequency listed in Table 4.2 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 130577, Total Dissolved Solids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226951
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 2 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130577, Total Dissolved Solids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226746
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 72
Number of Exceedances: 53
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 53 of 72 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-16 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130577, Total Dissolved Solids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226614
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 87
Number of Exceedances: 38
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 38 of 87 samples exceed the criterion for Dissolved Solids.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The secondary MCL for Total Dissolved Solids is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130534
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: pH
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)(2020)
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 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Twenty-four lines of evidence are available in the administrative record to assess pollutant. 20 of the 96 samples exceed the objective for Non-Contact Recreation. 21 of the 91 samples exceed the objective for Water Contact Recreation. 1 of the 1 samples exceed the objective for COLD. 51 of 404 samples exceed the objective for WARM. 1 of the 1 samples exceed for Municipal & Domestic Supply.

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. 20 of the 96 samples exceed the objective for Non-Contact Recreation. 21 of the 91 samples exceed the objective for Water Contact Recreation. 1 of the 1 samples exceed the objective for COLD. 51 of 404 samples exceed the objective for WARM. 1 of the 1 samples exceed for Municipal & Domestic Supply 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: This decision was made by SWRCB staff.
 
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 removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229109
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 2 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229074
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC525)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228367
 
Pollutant: pH
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2014-07-09 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226623
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 98
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 15 of 98 samples exceed the criterion for pH, with pH values greater than 8.5.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009. The results of samples collected on the same date and at the same location were averaged before they were assessed.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228506
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228372
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC527)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2010-09-07
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228737
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 2 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229068
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228369
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 2 of 10 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCHW)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2017-01-10
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228366
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229117
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC525)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229115
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC527)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2010-09-07
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229073
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 71
Number of Exceedances: 14
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 14 of 71 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-16 and 2017-08-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226501
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 102
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 102 samples from November 2004 to November 2005. None of the 102 samples had a pH value lower than 6.5.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH. Measurement of pH within the range of 6.5 and 8.5. A low pH has a value less than 6.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at five locations along Del Puerto Creek: Deer Creek, Rogers, Del Puerto Mile 3.9, Del Puerto Mile 13.6, and Highway 33.
Temporal Representation: Sampling occurred from November 2004 to November 2005
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226500
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 51
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Westside San Joaquin River Water Quality Coalition collected 51 samples from July 2004 to October 2006. Eight of the 51 samples did not meet the evaluation objective. Three samples had a pH lower than 6.5.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH. Measurement of pH within the range of 6.5 and 8.5. A low pH has a value less than 6.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Sampling occurred from July 2004 to October 2006
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226499
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 102
Number of Exceedances: 25
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 102 samples from November 2004 to November 2005. Twenty-five out of the 102 samples had a pH value over 8.5 and thus did not meet the evaluation objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH. Measurement of pH within the range of 6.5 and 8.5. A high pH value is greater than 8.5
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at five locations along Del Puerto Creek:Deer CreekRogersDel Puerto Mile 3.9Del Puerto Mile 13.6Highway 33
Temporal Representation: Sampling occurred from November 2004 to November 2005
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226498
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 51
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Westside San Joaquin River Water Quality Coalition collected 51 samples from July 2004 to October 2006. Eight of the 51 samples did not meet the evaluation objective. Five samples had a pH higher than 8.5.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH. Measurement of pH within the range of 6.5 and 8.5. A high pH value is greater than 8.5
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Sampling occurred from July 2004 to October 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226448
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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: SWAMP data indicates that the sample result exceeds the criterion for pH.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226447
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that the sample result exceeds the criterion for pH.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226449
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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: SWAMP data indicates that the sample result exceeds the criterion for pH.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228606
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
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 Stream Pollution Trends data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2014-07-09 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228374
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
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 RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228605
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 10
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 2 of 10 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCHW)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2017-01-10
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130534, pH
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229099
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 71
Number of Exceedances: 14
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 14 of 71 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-16 and 2017-08-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130567
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Bifenthrin
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Expected Attainment Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under section 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #21939, #21940, 62538 and was replaced by #226828, #226830 and #226829.

14 lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.

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. Eight of 22 water samples exceeded the evaluation guideline for WARM and 17 of 20 sediment samples exceeded the evaluation guideline for WARM and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. Additionally, 42 of 59 sediment samples exhibited significant toxicity.
4. This listing is being addressed through the Central Valley Regional Water Quality Control Board, Irrigated Lands Regulatory Program (ILRP) General Orders that have been approved by the RWQCB. The ILRP will implement management plans to address the pollutant and is expected to attain applicable water quality standards before or by 2037.
5. Pursuant to section 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 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:
 
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226593
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed data for Del Puerto Creek to determine beneficial use support and results are as follows: 8 of 8 samples exceed the criterion for bifenthrin. One additional sample was not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the sample was below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for bifenthrin in sediment (0.043 ug/g OC), is one-tenth of the geometric mean (0.43 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by 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: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event
Environmental Conditions: Two of the nine sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226634
 
Pollutant: Bifenthrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2013-09-09 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226645
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2014-07-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226758
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226760
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 5 of the 5 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for bifenthrin, 0.043 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226828
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water samples were collected from Del Puerto Creek from June 2003 through February 2005, representing 20 concentrations. 8 of 20 concentrations exceeded the maximum value (0.00093 ug/L).
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions:
QAPP Information: Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226830
 
Pollutant: Bifenthrin
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: 2 water samples were collected from Del Puerto Creek from July 2006 through August 2006, representing 2 concentrations.0 of 2 concentrations exceeded the upper limit value (0.00093 ug/L).
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Samples were collected from Del Puerto Creek at Highway 33.
Temporal Representation: Samples were collected monthly between July 2006 and August 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130567, Bifenthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226829
 
Pollutant: Bifenthrin
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Bifenthrin. Nine samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130516
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2020)
Revision Status Revised
Sources: Agriculture
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of chlorpyrifos to this segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under section 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Thirteen lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM) and Municipal and Domestic Supply (MUN). Twenty of the 204 samples exceed the guideline for COLD. Zero of the ten samples exceed the guideline for MUN.

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. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.

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. Twenty of the 204 samples exceed the guideline for WARM and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. In 2016, the Board adopted Resolution R5-2014-0041 establishing Basin Plan amendments that primarily address the regulation of agricultural pesticide runoff and discharges of diazinon and chlorpyrifos in the Central Valley which are implemented through Board established Waste Discharge Requirements for agricultural dischargers. The amendments established numeric water quality objectives for chlorpyrifos and a control program to ensure that the objectives will be attained within a reasonable, specified time frame.
The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval.
5. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water.
6. Pursuant to section 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 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 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226520
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the eleven samples collected, one exceeded the criteria for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Calif. DFG 4-day average for chlorpyrifos is 0.015 ug/L for freshwater aquatic life.
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
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226519
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the ten samples exceeded the water quality objective.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: USEPA Health Advisory 2011 ed., criteria for chlorpyrifos in freshwater is 2.0 ug/L (represents a life-time risk).
Guideline Reference: 2011 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226762
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos, 0.177 ug/g, is one-tenth of the median lethal concentration (LC50; 1.77 ug/g) and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226761
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective 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 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos, 0.177 ug/g, is one-tenth of the median lethal concentration (LC50; 1.77 ug/g) and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226668
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 6 of 53 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226602
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: One of the ten samples exceeded the evaluation guideline.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Criteria Continuous Concentration (four day average) for chlorpyrifos in freshwater is 0.014 ug/L.
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
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226601
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 20 samples exceed the criterion for Chlorpyrifos.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226454
 
Pollutant: Chlorpyrifos
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 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226467
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 32 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 32 4-day average concentrations and 32 1-hour average concentrations.4 of 32 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 4 of 32 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion 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
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Rox Road.
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226468
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 45
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 54 Water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 45 4-day average concentrations and 54 1-hour average concentrations.4 of 45 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 4 of 54 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion 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
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226471
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 3 4-day average concentrations and 19 1-hour average concentrations.2 of 3 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 4 of 19 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: Samples were collected at variable intervals (hourly or daily) from February to March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226472
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 4-day average concentrations and 19 1-hour average concentrations.1 of 19 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 ug/L. 1 of 19 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - 0.015 ug/L 4-day average and 0.025 ug/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: Samples were collected at variable intervals (biweekly and weekly) from March through August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130516, Chlorpyrifos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226909
 
Pollutant: Chlorpyrifos
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130512
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2020)
Revision Status Revised
Sources: A Source Unknown | Agriculture
Expected Attainment Date: 2037
Implementation Action Other than TMDL: Resolution R5-2017-0057, a Basin Plan Amendment for Pyrethroid Discharges, established a conditional prohibition of pyrethroids discharges. The Amendment requires agricultural dischargers of pyrethroids with known pyrethroid impairments develop and implement management plans through the Irrigated Lands Regulatory Program to reduce pyrethroid pesticides discharges. Del Puerto Creek was identified in the resolution and should obtain the narrative water quality objective for toxicity as soon as practicable, but no later than 20 years from the resolution date.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status. 12 lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.
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 eight sediment samples exceeded the evaluation guideline for WARM and 57 of 88 sediment toxicity samples exceeded the evaluation guideline for WARM. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board, Irrigated Lands Regulatory Program (ILRP) General Orders that have been approved by the RWQCB. The ILRP will implement management plans to address the pollutant and is expected to attain applicable water quality standards before or by 2037.
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:
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226638
 
Pollutant: Cyfluthrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2013-09-09 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226636
 
Pollutant: Cyfluthrin
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total. Although a total of 3 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective 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: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-10 to 2013-07-10
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226528
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Del Puerto Creek to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for cyfluthrin. Seven additional samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the available samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cyfluthrin in sediment (0.11 ug/g OC), is one-tenth of the geometric mean (1.1 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by 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: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226831
 
Pollutant: Cyfluthrin
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Thirteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-8/14/2007.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226770
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective 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 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541XDPCCR.
Temporal Representation: Date for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226768
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cyfluthrin, total. 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 objective 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 data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cyfluthrin, 0.11 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130512, Cyfluthrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130513
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2037
Implementation Action Other than TMDL: Resolution R5-2017-0057, a Basin Plan Amendment for Pyrethroid Discharges, established a conditional prohibition of pyrethroids discharges. The Amendment requires agricultural dischargers of pyrethroids with known pyrethroid impairments develop and implement management plans through the Irrigated Lands Regulatory Program to reduce pyrethroid pesticides discharges. Del Puerto Creek was identified in the resolution and should obtain the narrative water quality objective for toxicity as soon as practicable, but no later than 20 years from the resolution date.

Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status.

15 lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.
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. 14 of 17 samples exceeded the evaluation guideline for WARM and 57 of 78 sediment samples exceeded exhibited significant toxicity. These exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board, Irrigated Lands Regulatory Program (ILRP) General Orders that have been approved by the RWQCB. The ILRP will implement management plans to address the pollutant and is expected to attain applicable water quality standards before or by 2037.
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 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:
 
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226533
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Del Puerto Creek to determine beneficial use support and results are as follows: 3 of 3 samples exceed the criterion for cyhalothrin, lambda. Six additional samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for cyhalothrin, lambda in sediment (0.044 ug/g OC), is one-tenth of the geometric mean (0.44 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by 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: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226834
 
Pollutant: Cyhalothrin, Lambda
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. Nine samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226777
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226773
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226644
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 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: Technical basis for deriving sediment criteria for nonionic organic contaminants for the protection of benthic organisms by using equilibrium partitioning. EPA822-R-93-011. Washington, D.C.: Office of Water, USEPA
 
Spatial Representation: Data were collected from 1 (Station Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2014-07-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226641
 
Pollutant: Cyhalothrin, Lambda
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin, 0.044 ug/g, is one-tenth of the median lethal concentration (LC50; 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: Technical basis for deriving sediment criteria for nonionic organic contaminants for the protection of benthic organisms by using equilibrium partitioning. EPA822-R-93-011. Washington, D.C.: Office of Water, USEPA
 
Spatial Representation: Data were collected from 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2013-09-09 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130513, Cyhalothrin, Lambda
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
130525
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Diuron
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2021
Implementation Action Other than TMDL: This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory program (ILRP) Waste Discharge Requirements (WDRs)
for Growers within the Western San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-R2) and in Waste Discharge Requirements General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100). The sources of diuron to this waterbody segment have been identified as offsite movement of diuron from diuron applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. The WDRs monitoring and reporting program requires growers to regularly monitor water bodies with management plans to assess progress at meeting standards and regularly report monitoring results to the Regional Board. A management plan for diuron in Del Puerto Creek was developed in 2011 and is being implemented and monitoring is ongoing.
Agricultural management practices being used to reduce offsite movement of diuron into surface water include alternative weed management practices, pesticide application practices, vegetation management and water management practices, all of which are effective in reducing offsite movement of diuron into surface water. The WDRs require management practices to be iteratively improved through updates of the management plans until water quality criteria are achieved. The diuron criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This water body and pollutant combination is being reconsidered, during the 2014 Integrated Report cycle, for removal from the 303(d) list under section 2.2 of the Listing Policy. The evidence indicated that diuron concentrations are not attaining water quality standards.

Under section 4.11, a single line of evidence is necessary to assess listing status. Seven lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Nine of the 98 samples, reported as a total concentration or with the fraction not reported, exceed the guideline for WARM. LOE 95355 replaced LOE 21944 for this assessment. LOE 95355 re-assessed data previously evaluated in LOE 21944 according to a new evaluation guideline. The evidence indicates that diuron concentrations are not attaining the applicable water quality standards, but other pollution control requirements, under State authority, are stringent enough to implement applicable water quality standards.

Based on the readily available data and information, the weight of evidence indicates this water segment-pollutant combination is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame.

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. Nine of 98 samples exceeded the water quality guideline and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory program (ILRP) Waste Discharge Requirements (WDRs) for Growers within the Western San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2014-0002-R2) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).

The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for diuron in Del Puerto Creek was developed in 2011 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of diuron into surface water include alternative weed management practices, pesticide application practices, vegetation management and water management practices. The diuron criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being 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 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226469
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two water samples were collected at Del Puerto Creek in 2006.1 of 2 concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 ug/L (ECOTOX, 2008).
Guideline Reference: Ecotox database
 
Spatial Representation: Del Puerto Creek at Vineyard Avenue
Temporal Representation: Samples were collected daily during a storm event on February 28 and March 1, 2006.
Environmental Conditions:
QAPP Information: Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226494
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Four water samples were collected at Del Puerto Creek in 2006.0 of 4 concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 ug/L (ECOTOX, 2008).
Guideline Reference: Ecotox database
 
Spatial Representation: Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: Samples were collected on 7/11/2006 and 08/08/2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226495
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Six water samples were collected at Del Puerto Creek on March 15, 2003. Because all samples were collected within a 6 hour period of time, the mean was taken of the samples and compared to the maximum concentration (EC50) for diuron.1 of 1 concentration exceeded the maximum concentration of 1.3 ug/L.
Data Reference: The Occurrence and Concentration of Esfenvalerate and Permethrin in Water and Sediment in the Sacramento and San Joaquin Watersheds
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 ug/L (ECOTOX, 2008).
Guideline Reference: Ecotox database
 
Spatial Representation: Del Puerto Creek at Vineyard Road.
Temporal Representation: Samples were collected hourly for 6 hours on March 15, 2003.
Environmental Conditions:
QAPP Information: Sampling was conducted using DPR¿s Standard Operating Procedures (SOPs) for pesticides (Bennett, 1997). Sample quality control was conducted according to Segawa, 1995.
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226924
 
Pollutant: Diuron
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Diuron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226625
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Two water samples were collected from Del Puerto Creek from February to March 2006 that were averaged using a 4-day average per the evaluation guideline resulting in 1 averaged concentration. One out of one averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Ave.
Temporal Representation: Samples were collected over two consecutive days and averaged using a 4-day average per the evaluation guideline (2/28/2006-3/1/2006).
Environmental Conditions:
QAPP Information: Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226626
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Eleven water samples were collected from Del Puerto Creek from October 2009 through August 2010 that were averaged using a 4-day average per the evaluation guideline resulting in 11 averaged concentrations. Zero out of 11 averaged concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: Diuron Water Quality Data from 2004-2011 from the Irrigated Lands Regulatory Program
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216: 105-141. Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Samples were collected from Del Puerto Creek at from two monitoring sites: [three samples were collected from Del Puerto Creek at Hwy 33 - 541STC523 and 11 samples were collected from Del Puerto Creek near Cox Road ¿ 541XDPCCR]
Temporal Representation: Samples were collected approximately monthly from October 2009 through August 2010.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226688
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 3 of 56 samples exceeded the water quality threshold for Diuron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130525, Diuron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226612
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support.
Four of 20 samples results were detected at levels above Diuron criterion of 1.3 ug/L.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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: 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: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141. The acute exposure (4-day average) value for Diuron is 1.3 ug/L.
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites: [three samples were collected from Del Puerto Creek @ Hwy 33 - 541STC523, and 17 samples were collected from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130514
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Expected Attainment Date: 2037
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.

Fifteen lines of evidence are available in the administrative record to assess pollutant for Warm Freshwater Habitat (WARM). Zero of the nine water samples, reported as a dissolved concentration, exceed the guideline for WARM. Eight of the thirteen sediment samples, exceed the guideline for WARM. Fifty-seven of the 78 sediment toxicity samples, exceed the guideline for WARM.

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. Eight of the thirteen sediment samples, exceed the guideline for WARM. Fifty-seven of the 78 sediment toxicity samples, exceed the guideline for WARM. 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:
 
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226637
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 3 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2014-07-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226647
 
Pollutant: Esfenvalerate/Fenvalerate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2013-09-09 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226783
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 4 of the 5 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226785
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate, 0.15 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226835
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Esfenvalerate/Fenvalerate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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. The evaluation guideline for fenvalerate, 0.113 ug/L, is one-tenth of the median lethal concentration (LC50 = 1.13 ug/L) as determined in a 96 hour toxicity test using the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130514, Esfenvalerate/Fenvalerate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
 
DECISION ID
130511
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Pyrethroids
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2037
Implementation Action Other than TMDL: Resolution R5-2017-0057, a Basin Plan Amendment for Pyrethroid Discharges, established a conditional prohibition of pyrethroids discharges.

The Amendment requires agricultural dischargers of pyrethroids with known pyrethroid impairments develop and implement management plans through the Irrigated Lands Regulatory Program to reduce pyrethroid pesticides discharges. Del Puerto Creek was identified in the resolution and should obtain the narrative water quality objective as soon as practicable, but no later than 20 years from the resolution date.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under section 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eight of 11 sediment samples exceeded the evaluation guideline for the additive toxic effects of pyrethroids. Additionally, sediment samples exhibited significant toxicity. These results exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the Central Valley Regional Water Quality Control Board, Irrigated Lands Regulatory Program (ILRP) General Orders that have been approved by the RWQCB. The ILRP will implement management plans to address the pollutant and is expected to attain applicable water quality standards before or by 2037.
5. Pursuant to section 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 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:
 
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226806
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 2 of the 5 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226803
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226453
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
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: Toxicity Identification Evaluations (TIEs) were conducted on samples collected from Del Puerto Creek at Vineyard on 5/29/2002 and 9/11/2002. Toxicity was increased by the following TIE manipulations: addition of PBO and decrease of test temperatures, both suggesting evidence of pyrethroid pesticides (Central Valley Regional Water Quality Control Board, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998)
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130511, Pyrethroids
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
 
DECISION ID
130510
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2024
Implementation Action Other than TMDL: This listing is being addressed through the implementation of the Central Valley Water Board Irrigated Lands Regulatory program (ILRP), General Order R5-2014-0002, for the Westside San Joaquin River Watershed Coalition (Coalition). The Coalition has two active management plans for toxicity that were developed prior to the General Order. The Westside San Joaquin River Watershed Coalition Management Plan General Approach was developed in 2008 and the Westside San Joaquin River Watershed Coalition Focused Watershed Management Plan II for Westley Wasteway, Del Puerto Creek, Orestimba Creek was developed in 2010. Both management plans stated the sources of toxicity identify agricultural practices as a significant contributor and require ongoing monitoring of the water bodies to assess progress at meeting water quality standards. Agricultural management practices to reduce toxicity in surface water include integrated pest management programs, conversion to high-efficiency irrigation systems, vegetation management and water management practices. The management plans are required to be updated until water quality criteria are achieved.
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.

Fifteen lines of evidence are available in the administrative record to assess this pollutant. Toxicity tests were conducted for Ceriodaphnia survival, Pimephales survival and Selenastrum growth. Twenty-eight of 87 water samples tested with Selenastrum capricornutum exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use. Fifty-seven of 78 sediment samples tested with Hyalella azteca exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use.

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. Twenty-eight of 87 water samples tested with Selenastrum capricornutum exhibited significant toxicity. Fifty-seven of 78 sediment samples tested with Hyalella azteca exhibited significant toxicity and exceed the evaluation guideline for the WARM beneficial use. This exceeds the allowable frequency in Table 3.1.
4. A water quality management plan for toxicity in Del Puerto Creek was approved by the Central Valley Water Board Irrigated Lands Regulatory Program. Management practices were implemented by growers to address toxicity exceedances.
5. Del Puerto Creek was originally identified as impaired by toxicity in 2014.
6. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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.
 
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 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226510
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 23
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 23 of 37 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective. Nine samples collected at Deer Creek Campground exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:16 November 2004 (81)21 December 2004 (77)17 May 2005 (75)21 June 2005 (87)19 July 2005 (83)16 August 2005 (78)20 September 2005 (77)18 October 2005 (66)15 November 2005 (85)\Ten samples collected at Del Puerto Mile 3.9 exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:15 February 2005 (81)23 March 2005 (87)19 April 2005 (71)17 May 2005 (64)21 June 2005 (70)19 July 2005 (66)16 August 2005 (71)20 September 2005 (71)18 October 2005 (62)15 November 2005 (75)Four samples collected at Highway 33 exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:21 December 2004 (4)15 February 2005 (22)23 March 2005 (75)21 June 2005 (57)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 4-day chronic-style toxicity tests.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-013
 
Spatial Representation: Samples were collected from Del Puerto Creek at Deer Creek Campground, Del Puerto Mile 3.9 and Highway 33.
Temporal Representation: Samples were collected from November 2004 to November 2005 at monthly intervals.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226530
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Ten samples were tested for toxicity. None of the ten samples exhibited statistically significant effect relative to control. The toxicity tests included Ceriodaphnia dubia survival.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing (parametric Dunnett's Test or non-parametric Kruskal-Wallis or Wilcoxon Two-sample Test). The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected in Del Puerto Creek at Vineyard Avenue near the town of Patterson.
Temporal Representation: Samples were collected once to twice a month from December 2007 through June 2008.
Environmental Conditions:
QAPP Information: Data quality is good. The data report Pesticide Concentrations in Water and Sediment and Associated Invertebrate Toxicity in Del Puerto and Orestimba Creeks, California, from the Department of Pesticide Regulation contains QA information.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226517
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 6
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifty-four samples were collected to evaluate water toxicity. Six of the samples exhibited significant toxicity. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and cell count of Selenastrum capricornutum. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold. This data set reports a simple pass/fail (Yes/No) code to report toxicity that is equivalent to the SWAMP SL code.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from July 2004 to August 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226633
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 3 of the 50 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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, Pimephales promelas, for Survival, Selenastrum capricornutum, for Total Cell Count
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2015-09-15.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226502
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: None of the 13 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a Fisher's Exact analysis with 4-day acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33
Temporal Representation: Samples were collected from November 2004 to November 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226470
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One of the 13 samples tested with Ceriodaphnia dubia was toxic and violated the narrative toxicity objective. One sample collected at Del Puerto Creek at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:21 December 2004 (0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a Fisher's Exact analysis with 4-day acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33.
Temporal Representation: Samples were collected from November 2004 to November 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130510, Toxicity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
 
DECISION ID
130691
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
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 130691, 2,4-D (2,4-Dichlorophenoxy acetic acid)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226873
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 DWR data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, and Pesticides in Regions 2,5 and 6, 2004-2010.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for 2,4-D (2,4-Dichlorophenoxy acetic acid) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (DMC06715)
Temporal Representation: The samples were collected between the dates of 2004-09-15 and 2006-09-20
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan for Bryte Chemical Laboratory
QAPP Information Reference(s): Quality Assurance Project Plan from Bryte Chemical Laboratory.
 
 
DECISION ID
130557
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Aldicarb
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226648
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226649
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226838
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226891
 
Pollutant: Aldicarb
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226892
 
Pollutant: Aldicarb
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226959
 
Pollutant: Aldicarb
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130557, Aldicarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226575
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Aldicarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Department of Public Health archived advisory level for aldicarb is 7 ug/L.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130558
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Aldrin
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226583
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Aldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for aldrin to protect human health from the consumption of water and organisms is 0.00013 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226650
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from consumption of organisms only is 0.00014 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226651
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Aldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The established numeric criteria for aldrin to protect aquatic life in freshwater as an instantaneous maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote (g) of Table (b)(1) of the 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226652
 
Pollutant: Aldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. Although a total of 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226894
 
Pollutant: Aldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Aldrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The established numeric criteria for aldrin to protect aquatic life in freshwater as an instantaneous maximum concentration is 3 ug/L . This established criteria was divided by 2 in order to better represent a CMC value as specified in footnote (g) of Table (b)(1) of the 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226893
 
Pollutant: Aldrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Aldrin. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Aldrin criteria for the protection of human health from the consumption of water and organisms is 0.00013 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130558, Aldrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226576
 
Pollutant: Aldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Aldrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion maximum concentration to protect aquatic life in freshwater for aldrin is 1.5 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130501
Region 5     
Del Puerto Creek (Stanislaus County)
 
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 130501, Alkalinity as CaCO3
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226437
 
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: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Alkalinity as CaCO3.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Alkalinity as CaCO3 levels were assessed for the protection of freshwater aquatic life by comparison to the Evaluation Guideline value of 20,000 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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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
130594
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Anthracene
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)(2020)
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 130594, Anthracene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226755
 
Pollutant: Anthracene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Anthracene is 845 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130562
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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.

Seven lines of evidence are available in the administrative record to assess this pollutant. One of the 64 samples exceed the objective for the MUN beneficial use. Zero of 69 samples exceed the criteria for the WARM beneficial use. Zero of five sediment samples exceed the evaluation guideline.

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. One of the 64 samples exceed the objective for the MUN beneficial use. Zero of 69 samples exceed the criteria for the WARM beneficial use. Zero of five sediment samples exceed the evaluation guideline.
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 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226896
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 150 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226584
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226585
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for arsenic is 0.010 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226654
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 33 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226655
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 150 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226756
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Arsenic from MacDonald et al., 2000a which states that the probable effect concentration for Arsenic is 33 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130562, Arsenic
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226895
 
Pollutant: Arsenic
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for arsenic incorporated by reference in the Basin Plan is 0.010 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130563
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Atrazine
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 62525 has been replaced by LOE 221411 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226586
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Atrazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for atrazine is 1 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226960
 
Pollutant: Atrazine
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Atrazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-12-29 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226897
 
Pollutant: Atrazine
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226898
 
Pollutant: Atrazine
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226836
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Atrazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226657
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130563, Atrazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226656
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130529
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Azinphos-methyl (Guthion)
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)(2020)
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.

Seven lines of evidence are available in the administrative record to assess this pollutant. 1 of the 124 samples exceed the evaluation guideline.

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. 1 of the 124 samples exceed the evaluation guideline 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 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226478
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 19 concentrations.0 of 19 available concentrations exceeded the criterion of 0.01 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: Water quality criterion is 0.01 ug/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vinyard Road.
Temporal Representation: Samples were collected daily during two storms in February and March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226481
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 54 water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 54 concentrations. 1 of 54 concentrations exceeded criterion of 0.01 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: Water quality criterion is 0.01 ug/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. daily, weekly) from January 2000 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226591
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos methyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The National Recommended Water Quality criterion for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226480
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 32 water samples were collected from Del Puerto Creek from April 2005 through August 2006, representing 32 concentrations.0 of 32 available concentrations exceeded the water quality criterion (0.01 ug/L).
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: Water quality criterion is 0.01 ug/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected from Del Puerto Creek at highway 33 and near Cox Road.
Temporal Representation: Samples were collected at daily and biweekly intervals from April 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226899
 
Pollutant: Azinphos-methyl (Guthion)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)
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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226479
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 concentrations.0 of 19 available concentrations exceeded criterion of 0.01 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Evaluation Guideline: Water quality criterion is 0.01 ug/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: Samples were collected at variable intervals (weekly and biweekly) from March to August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130529, Azinphos-methyl (Guthion)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226653
 
Pollutant: Azinphos-methyl (Guthion)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 53 samples were collected, 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)
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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130593
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Benzo(a)anthracene
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)(2020)
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 130593, Benzo(a)anthracene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226754
 
Pollutant: Benzo(a)anthracene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130595
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Benzo(a)pyrene
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)(2020)
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 130595, Benzo(a)pyrene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226759
 
Pollutant: Benzo(a)pyrene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130519
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226597
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 sample dates exceed the criterion for Cadmium.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for cadmium is 5 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226658
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226901
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226660
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226458
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: None of the 8 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR criterion for dissolved cadmium
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved cadmium levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average dissolved)=(EXP(1.128*LN(hardness)-3.6867))*(1.136672-(LN(hardness)*0.041838))
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: Samples were collected from Del Puerto Creek at Vineyard Avenue
Temporal Representation: The samples were collected between September 26, 2001 and October 30, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226661
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226903
 
Pollutant: Cadmium
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226902
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for cadmium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.005 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130519, Cadmium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226757
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Cadmium from MacDonald et al., 2000a which states that the probable effect concentration for Cadmium is 4.98 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130569
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Carbaryl
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)(2020)
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. One of the 72 samples exceed the evaluation guideline for WARM.

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. One of the 72 samples exceed the evaluation guideline for WARM 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 130569, Carbaryl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226598
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Carbaryl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended water quality criterion for freshwater aquatic life for carbaryl is 2.1 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130569, Carbaryl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226665
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 56 samples exceeded the water quality threshold for Carbaryl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130569, Carbaryl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226904
 
Pollutant: Carbaryl
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbaryl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130570
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Carbofuran
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226666
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226905
 
Pollutant: Carbofuran
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226906
 
Pollutant: Carbofuran
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226663
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226600
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Carbofuran is 18 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130570, Carbofuran
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226599
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater criterion maximum concentration for carbofuran is 0.5 µg/L (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130586
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Chlordane
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)(2020)
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 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226763
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226667
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from consumption of organisms only is 0.00059 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226907
 
Pollutant: Chlordane
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).
Guideline 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
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226662
 
Pollutant: Chlordane
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 54 samples were collected, 54 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Chlordane criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0043 ug/L (California Toxics Rule, 2000).
Guideline 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
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226664
 
Pollutant: Chlordane
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from the consumption of water and organisms is 0.00057 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130586, Chlordane
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226908
 
Pollutant: Chlordane
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane criterion for the protection of human health from the consumption of water and organisms is 0.00057 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130573
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Chlordane, cis
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 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. Zero of the zero samples exceed the water quality criteria.


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. Zero of the zero samples exceed the water quality criteria 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 are needed to determine if a beneficial use is fully supported using table 3.1.
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 130573, Chlordane, cis
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226608
 
Pollutant: Chlordane, cis
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: The reporting limit for every sample analyzed for chlordane is greater than the criterion for Chlordane. Therefore, the data could not be assessed with the level of reliability required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chlordane (Total, cis, trans), CTR (water and fish consumption) to protect human health is 0.00057 ug/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 Del Puerto Creek was collected at 2 monitoring sites [three samples from Del Puerto Creek @ Hwy 33 - 541STC523, and 17 samples from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130503
Region 5     
Del Puerto Creek (Stanislaus County)
 
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: 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 line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the California Secondary MCL for the protection of all drinking water uses for MUN.

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 one samples exceed the California Secondary MCL for the protection of all drinking water uses for MUN 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 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 130503, Chloride
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226440
 
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: SWAMP data indicates that 0 of the sample results exceed the criterion for Chloride.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminat Levels for chloride provide a range of values including a recommended level (250 mg/L), an upper level (500 mg/L) and a short-term level (600 mg/L). The recommended level of 250 mg/L was used as it is intended to be protective of all drinking water uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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
130596
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Chrysene (C1-C4)
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)(2020)
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 130596, Chrysene (C1-C4)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226764
 
Pollutant: Chrysene (C1-C4)
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130541
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226910
 
Pollutant: Copper
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226911
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226912
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226522
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for copper is 1.0 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226521
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 AgWaiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The 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 metals criteria.
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 Del Puerto Creek was collected at 1 monitoring site [ Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/14/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226765
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Copper from MacDonald et al., 2000a which states that the probable effect concentration for Copper is 149 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226671
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226670
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130541, Copper
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226669
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130542
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Cyanazine
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130542, Cyanazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226672
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Cyanazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130542, Cyanazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226913
 
Pollutant: Cyanazine
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Cyanazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130542, Cyanazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226523
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Cyanazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The EC50 for Navicula pelliculosa (freshwater diatom) for cyanazine is 4.8 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130539
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226640
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226635
 
Pollutant: Cypermethrin
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2014-07-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226514
 
Pollutant: Cypermethrin
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: A total of 17 individual sediment samples were collected; 17 samples were below both the reporting limit (0.11 - 0.35 ug/kg dry weight) and the organic carbon normalized evaluation guideline (0.03 ug/g OC) and could not be quantified with the level of certainty required by the listing policy. 0 of 0 samples exceeded the evaluation guideline.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: The narrative objective for pesticides states, "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 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: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s): Quality Assurance Project Plan for Pyrethroid Working Group.
 
Line of Evidence (LOE) for Decision ID 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226832
 
Pollutant: Cypermethrin
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Nine samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226775
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226772
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for cypermethrin, 0.03 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130539, Cypermethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226833
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the ten samples collected, none exceeded the criteria for cypermethrin for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions:
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130587
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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)(2020)
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 130587, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226673
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130587, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226675
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD criteria for the protection of human health from consumption of organisms only is 0.00084 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130587, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226914
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDD(p,p'). 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDD(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130587, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226771
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130587, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226769
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130575
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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)(2020)
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 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226778
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226804
 
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: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 4 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 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2014-03-10 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226805
 
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: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 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 data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226916
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226917
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226679
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT-4,4' criteria for the protection of human health from consumption of organisms only is 0.00059 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226680
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT(p,p) criteria for the protection of human health from the consumption of water and organisms is 0.00059 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226767
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226611
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support.
One of 24 sample results was above reporting limit of 0.01 ug/L. Since the reporting limits were greater than the criterion for the other 23 samples, these were not assessed. One sample result exceeded the CTR value of 0.00059 ug/L.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for total DDT to protect human health from the consumption of water and organisms is 0.00059 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites: [five samples were collected from Del Puerto Creek @ Hwy 33 - 541STC523, and 19 samples were collected from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226624
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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 Ag Waiver data for Del Puerto Creek to determine beneficial use support.
One of 24 sample results was above reporting limit of 0.01 ug/L. Since the reporting limits were greater than the criterion for the other 23 samples, these were not assessed. One sample result (0.01 ug/L) exceeded the CTR aquatic life protection value of 0.001 ug/L.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective to protect aquatic life from chronic exposure to DDT is 0.001 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites: [five samples were collected from Del Puerto Creek @ Hwy 33 - 541STC523, and 19 samples were collected from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected between 7/11/2006 and 8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130575, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226678
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for DDT(p,p'). Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130540
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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 130540, Deltamethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226779
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130540, Deltamethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226781
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130540, Deltamethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226537
 
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: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for deltamethrin. Nine additional samples were not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the samples were below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for deltamethrin in sediment (0.079 ug/g OC), is one-tenth of the geometric mean (0.79 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by 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: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Two of the nine samples were taken after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130540, Deltamethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226515
 
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: A total of 17 individual sediment samples were collected; 17 samples were below both the reporting limit (0.11 - 0.35 ug/kg dry weight) and the organic carbon normalized evaluation guideline (0.079 ug/g OC) and could not be quantified with the level of certainty required by the listing policy. 0 of 0 samples exceeded the evaluation guideline.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: The narrative objective for pesticides states, "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for deltamethrin, 0.079 ug/g, is one-tenth of the median lethal concentration (LC50; 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: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s): Quality Assurance Project Plan for Pyrethroid Working Group.
 
 
DECISION ID
130576
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Demeton
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130576, Demeton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226918
 
Pollutant: Demeton
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA Recommended freshwater eaquatic life criteria for demeton is 0.1 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130576, Demeton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226613
 
Pollutant: Demeton
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: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Demeton.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: 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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA National Recommended freshwater aquatic life criteria for demeton 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: Data for this line of evidence for Del Puerto Creek was collected at 1 monitoring site [ Del Puerto Creek @ Hwy 33 - 541STC523]
Temporal Representation: Data was collected on a single day 12/29/2004.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130576, Demeton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226681
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA Recommended freshwater eaquatic life criteria for demeton is 0.1 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130544
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Dichlorvos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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 130544, Dichlorvos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226920
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 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 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130544, Dichlorvos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226961
 
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) 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 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2004-07-06 to 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130544, Dichlorvos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226684
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 53 samples were collected, 53 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 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130544, Dichlorvos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226837
 
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 ILRP_WSWQC data for Del Puerto Creek 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 12 samples were collected, 12 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 in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2004-07-06 to 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130544, Dichlorvos
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226541
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Dichlorvos.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Dichlorvos, 7.2 ug/L, is the maximum acceptable toxicicant concentration (MATC) for Oncorhyncus mykiss (Rainbow trout); USEPA Office of Pesticide Programs Ecotoxicity database.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130588
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Dicofol
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130588, Dicofol
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226682
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Dicofol.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130588, Dicofol
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226962
 
Pollutant: Dicofol
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dicofol.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130588, Dicofol
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226921
 
Pollutant: Dicofol
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Dicofol.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130588, Dicofol
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226841
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Dicofol.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130545
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Disulfoton
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130545, Disulfoton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226545
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for disulfoton, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA IRIS Reference dose (RfD) as a drinking water level for disulfoton is 0.3 ug/L.
Guideline Reference: Drinking Water Notification and Response Levels: An Overview
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130545, Disulfoton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226544
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Disulfoton.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA National Recommended Water Quality criterion for disulfoton in freshwater (0.05 ug/L) is an aquatic life maximum (instantaneous) level.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130545, Disulfoton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226687
 
Pollutant: Disulfoton
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 53 samples were collected, 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130545, Disulfoton
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226923
 
Pollutant: Disulfoton
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130581
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130581, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226965
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for EPTC.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130581, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226846
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for EPTC.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130581, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226935
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for EPTC.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130581, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226702
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for EPTC.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for EPTC (Eptam, s-ethyl dipropylthiocarbamate) is the USEPA Aquatic Life Benchmark of 40 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130581, EPTC (Eptam, s-ethyl dipropylthiocarbamate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226618
 
Pollutant: EPTC (Eptam, s-ethyl dipropylthiocarbamate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 39 samples exceed the criterion for EPTC.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: 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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: According to the USEPA Office of Pesticide Programs Ecotoxicity database, the freshwater aquatic life MATC for EPTC is 1000 ug/L.
Guideline Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009. The results for samples collected within a 7-day period were averaged before they were assessed.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130580
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Endosulfan sulfate
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226700
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226693
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan sulfate criteria for the protection of human health from the consumption of water and organisms is 110 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226617
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Endosulfan sulfate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan Sulfate criterion to protect human health for waters that include the designated use of MUN is 110 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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226931
 
Pollutant: Endosulfan sulfate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan sulfate criteria for the protection of human health from the consumption of water and organisms is 110 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226932
 
Pollutant: Endosulfan sulfate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for endosulfan sulfate for freshwater aquatic life protection is 0.056 ug/l (24 hour average)
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130580, Endosulfan sulfate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226701
 
Pollutant: Endosulfan sulfate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Endosulfan Sulfate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan Sulfate criteria for the protection of human health from consumption of organisms only is 240 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130546
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Endrin
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226548
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion for the protection of human health from the consumption of water and organisms is 0.76 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226933
 
Pollutant: Endrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226934
 
Pollutant: Endrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226780
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226547
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226697
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from the consumption of water and organisms is 0.76 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226694
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Endrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criteria for the protection of human health from consumption of organisms only is 0.81ug/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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130546, Endrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226695
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for Endrin. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130537
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Fenpropathrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130537, Fenpropathrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226786
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective 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 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541XDPCCR.
Temporal Representation: Date for this waterbody were collected over the date range 2014-03-10 to 2015-09-14
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130537, Fenpropathrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226788
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130537, Fenpropathrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226512
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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: A total of 17 individual sediment samples were collected; 0 of 17 exceeded the evaluation guideline (0.12 ug/g OC).
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: The narrative objective for pesticides states, "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for fenpropathrin, 0.1 ug/g, is one-tenth of the median lethal concentration (LC50; 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: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s): Quality Assurance Project Plan for Pyrethroid Working Group.
 
 
DECISION ID
130599
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Fluoranthene
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)(2020)
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 130599, Fluoranthene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226795
 
Pollutant: Fluoranthene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Fluoranthene from MacDonald et al., 2000a which states that the probable effect concentration for Fluoranthene is 2230 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130601
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Fluorene
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)(2020)
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 130601, Fluorene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226797
 
Pollutant: Fluorene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130547
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Glyphosate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130547, Glyphosate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226552
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceed the criterion for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Glyphosate is 700 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-1/6/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130547, Glyphosate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226551
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceed the criterion for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for glyphosate, 5,500 ug/L, is one-tenth of the median lethal concentration (LC50 = 55,000 ug/L) for Chironimus plumosus (Midge). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-1/6/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130547, Glyphosate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226844
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2008-01-06
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130547, Glyphosate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226966
 
Pollutant: Glyphosate
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Glyphosate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2008-01-06
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130548
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Heptachlor
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)(2020)
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 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226940
 
Pollutant: Heptachlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226941
 
Pollutant: Heptachlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226553
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226554
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for Heptachlor to protect human health from the consumption of water and organisms is 0.00021 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226713
 
Pollutant: Heptachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from consumption of organisms only is 0.00021 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226714
 
Pollutant: Heptachlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criteria for the protection of human health from the consumption of water and organisms is 0.00021 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130548, Heptachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226715
 
Pollutant: Heptachlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor. Although a total of 54 samples were collected, 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130549
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Heptachlor epoxide
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)(2020)
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 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226712
 
Pollutant: Heptachlor epoxide
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 53 samples were collected, 53 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.0001 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226711
 
Pollutant: Heptachlor epoxide
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 53 samples were collected, 53 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226710
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. Although a total of 53 samples were collected, 53 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from consumption of organisms only is 0.00011 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226555
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226943
 
Pollutant: Heptachlor epoxide
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0038 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226556
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for Heptachlor epoxide to protect human health from the consumption of water and organisms is 0.0001 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130549, Heptachlor epoxide
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226942
 
Pollutant: Heptachlor epoxide
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Heptachlor Epoxide. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Heptachlor Epoxide criteria for the protection of human health from the consumption of water and organisms is 0.0001 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130589
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130589, Hexachlorocyclohexane (HCH), alpha
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226704
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for HCH, alpha-. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of organisms only is 0.013 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130589, Hexachlorocyclohexane (HCH), alpha
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226705
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, alpha-. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of water and organisms is 0.0039 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130589, Hexachlorocyclohexane (HCH), alpha
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226936
 
Pollutant: Hexachlorocyclohexane (HCH), alpha
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, alpha-. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-HCH (alpha-BHC) criteria for the protection of human health from consumption of water and organisms is 0.0039 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130590
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Hexachlorocyclohexane (HCH), beta
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130590, Hexachlorocyclohexane (HCH), beta
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226706
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for HCH, beta-. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from consumption of organisms only is 0.046 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130590, Hexachlorocyclohexane (HCH), beta
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226937
 
Pollutant: Hexachlorocyclohexane (HCH), beta
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, beta-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130590, Hexachlorocyclohexane (HCH), beta
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226707
 
Pollutant: Hexachlorocyclohexane (HCH), beta
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for HCH, beta-. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, beta criteria for the protection of human health from the consumption of water and organisms is 0.014 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130520
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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.

Nine lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM) and for Municipal and Domestic Supply (MUN). Zero of the five sediment samples exceed the guideline for WARM. Zero of the four water samples, with the fraction not reported, exceed the criterion for WARM. Zero of the 51 water samples, reported as a dissolved concentration, exceed the criterion for WARM. Zero of the 37 water samples, reported as a dissolved concentration, exceed the objective for MUN. One of the 37 water samples, reported as a total concentration, exceed the objective for MUN.

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. One of the 37 water samples, reported as a total concentration, exceed the objective for MUN 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 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226791
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Lead from MacDonald et al., 2000a which states that the probable effect concentration for Lead is 128 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226718
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226717
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226716
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 1 of 33 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226945
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 5.
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226944
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226946
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for use as MUN shall not contain lead in excess of 0.015 mg/l.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226557
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 AgWaiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Lead.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The 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 metals criteria.
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 Del Puerto Creek was collected at 1 monitoring site [ Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/14/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130520, Lead
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226459
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved lead
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved lead levels should not exceed the calculated CTR value based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(1.273*LN(hardness)-1.46))*(1.46203-(LN(hardness)*0.145712))
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: Samples were collected from Del Puerto Creek at Vineyard Avenue
Temporal Representation: The samples were collected between November 29, 2000 and October 30, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
130550
Region 5     
Del Puerto Creek (Stanislaus County)
 
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: Do Not List on 303(d) list (TMDL required list)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226939
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226938
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226559
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, gamma.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for HCH, gamma (Lindane) is 0.2 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226558
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, gamma.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-HCH (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226790
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma-. 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 objective 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 data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226709
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The gamma-BHC (Lindane) criterion maximum concentration to protect aquatic life in freshwater is 0.95 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226703
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for HCH, gamma-. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of water and organisms is 0.019 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130550, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226708
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for HCH, gamma-.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, gamma(Lindane) criteria for the protection of human health from the consumption of organisms only is 0.063 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130551
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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 130551, Malathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226948
 
Pollutant: Malathion
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130551, Malathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226560
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Malathion.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion, 0.028 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130551, Malathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226719
 
Pollutant: Malathion
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 53 samples were collected, 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130551, Malathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226561
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for malathion, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Calif. DHS Notification Level for malathion is 160 ug/L for drinking water.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130551, Malathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226562
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the eleven samples collected for malathion, none exceeded the criteria for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA Nat'l Recomm. maximum concentration (1-hour average) for malathion is 0.43 ug/L for freshwater 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 from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
 
DECISION ID
130908
Region 5     
Del Puerto Creek (Stanislaus County)
 
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 130908, Mercury
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226854
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Mercury from MacDonald et al., 2000a which states that the probable effect concentration for Mercury is 1.06 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130552
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Methidathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.

LOE 226563 has been replaced by LOE 226842 and 226968 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
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 130552, Methidathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226722
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130552, Methidathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226842
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Methidathion.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130552, Methidathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226564
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for methidathion, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA IRIS Reference Dose (RfD) for drinking water is 0.7 ug/L for methidathion.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130552, Methidathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226968
 
Pollutant: Methidathion
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methidathion.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130552, Methidathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226855
 
Pollutant: Methidathion
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130553
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Methiocarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.

LOE 226565 has been replaced by LOE 226847 and 226969 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
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 130553, Methiocarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226847
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130553, Methiocarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226723
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130553, Methiocarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226969
 
Pollutant: Methiocarb
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130553, Methiocarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226856
 
Pollutant: Methiocarb
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130554
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Methomyl
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130554, Methomyl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226857
 
Pollutant: Methomyl
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methomyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130554, Methomyl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226566
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Methomyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Methomyl, 0.5 ug/L, is a 4-day average value; CDFG, 1996.
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130554, Methomyl
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226724
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Methomyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130555
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Methoxychlor
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226859
 
Pollutant: Methoxychlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for methoxychlor for freshwater aquatic life protection is 0.03 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226858
 
Pollutant: Methoxychlor
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Methoxychlor incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.03 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226567
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226568
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Methoxychlor, 30 ug/L, is incorporated by reference into the (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins).
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226725
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Methoxychlor.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Methoxychlor incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.03 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130555, Methoxychlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226721
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for Methoxychlor. Although a total of 55 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for methoxychlor for freshwater aquatic life protection is 0.03 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130528
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Methyl Parathion
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)(2020)
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.

Nine lines of evidence are available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Zero of the four sediment samples exceed the guideline for WARM. Three of the 76 water samples exceed the guideline for WARM.

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. Three of the 76 water samples exceed the guideline for WARM 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 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226867
 
Pollutant: Methyl 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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226798
 
Pollutant: Methyl Parathion
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for methyl parathion, 0.6 ug/g, is one-tenth of the median lethal concentration (LC50; 6 ug/g) and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2015-07-15
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226737
 
Pollutant: Methyl 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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 53 samples were collected, 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226572
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Of the ten samples collected, none exceeded the criteria for methyl parathion for freshwater aquatic life.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Na'tl Recomm. WQ Criteria (USEPA) , max. instantaneous, for freshwater aquatic life is 0.08 ug/L for methyl parathion.
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 from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226571
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The ten samples collected did not exceed the water quality objective for methyl paration, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Dept. of Health Services Notification Level for methyl parathion is 2 ug/L for drinking water.
Guideline Reference: CDPH Archived Advisory Levels for Drinking Water. Archived Advisory Levels are currently considered Notification Levels.
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226570
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Parathion, Methyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The NAS health advisory level for methyl parathion is 30 µg/L.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226569
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226477
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 12 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 12 concentrations.3 of 12 available concentrations exceeded the interim water quality criterion 0.08 ug/L. 24 water samples had method detection limits (0.1 ug/L) higher than the Criterion (0.08 ug/L). So the 24 samples were not included in this analysis.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - Interim water quality criterion is 0.08 ug/L (Menconi and Harrington, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Samples were collected from Del Puerto Creek at two locations: Highway 33 and near Rox Road.
Temporal Representation: Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130528, Methyl Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226476
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 54 Water sample was collected from Del Puerto Creek from January 2000 through February 2005, representing 54 concentrations.0 of 54 available concentrations exceeded the interim water quality criterion 0.08 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Criteria - Interim water quality criterion is 0.08 ug/L (Menconi and Harrington, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Samples were collected from Del Puerto Creek at location (lat. 37.5217 and Long. -121.148)
Temporal Representation: Samples were collected at variable intervals (e.g. daily, weekly) from January 2000 through February 2005.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
 
DECISION ID
130692
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Metolachlor
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 130692, Metolachlor
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226874
 
Pollutant: Metolachlor
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 DWR data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Metolachlor.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, and Pesticides in Regions 2,5 and 6, 2004-2010.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Metolachlor is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (DMC06715)
Temporal Representation: The samples were collected between the dates of 2006-06-21 and 2006-06-21
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan for Bryte Chemical Laboratory
QAPP Information Reference(s): Quality Assurance Project Plan from Bryte Chemical Laboratory.
 
 
DECISION ID
130556
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Molinate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130556, Molinate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226875
 
Pollutant: Molinate
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 DWR data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Molinate.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, and Pesticides in Regions 2,5 and 6, 2004-2010.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.
Guideline Reference: Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division
 
Spatial Representation: The samples were collected at 1 monitoring site (DMC06715)
Temporal Representation: The samples were collected between the dates of 2004-06-16 and 2004-06-16
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan for Bryte Chemical Laboratory
QAPP Information Reference(s): Quality Assurance Project Plan from Bryte Chemical Laboratory.
 
Line of Evidence (LOE) for Decision ID 130556, Molinate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226843
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.
Guideline Reference: Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2007-08-14
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130556, Molinate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226574
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Molinate is 20 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130556, Molinate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226573
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Molinate, 600 ug/L, the maximum acceptable toxicicant concentration (MATC) for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130556, Molinate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226970
 
Pollutant: Molinate
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Molinate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.
Guideline Reference: Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-12-29 and 2007-05-08
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130592
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Molybdenum
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)(2020)
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 130592, Molybdenum
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226731
 
Pollutant: Molybdenum
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Molybdenum.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 10 ug/L criteria is the recommended maximum concentration of molybdenum in irrigation water.
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2016-03-08 and 2016-03-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130602
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Naphthalene
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)(2020)
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 130602, Naphthalene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226799
 
Pollutant: Naphthalene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Naphthalene from MacDonald et al., 2000a which states that the probable effect concentration for Naphthalene is 561 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130521
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Nitrate as Nitrate (NO3)
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 130521, Nitrate as Nitrate (NO3)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226461
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 11 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Nitrate-N levels should not to exceed 100 mg/L (USEPA National Ambient Water Quality Objective)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: The samples were collected from Oct 24 2000 to Oct 24 2001
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
130500
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Nitrite as Nitrite NO2
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 130500, Nitrite as Nitrite NO2
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226436
 
Pollutant: Nitrite as Nitrite NO2
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: 0 of 1 samples exceed the water quality objective for Nitrite (as N). The Nitrite (as N) MCL objective is 1 mg/L. The data are reported as non-detects. These non-detects are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The Nitrite (as N) MCL is 1 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at 542DPCDPC (Del Puerto Creek).
Temporal Representation: Samples collected on 6/18/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
130560
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Nitrogen, Nitrate
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.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the 16 samples exceed the water quality 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 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 16 samples exceed the water quality objective 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 130560, Nitrogen, Nitrate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226580
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Nitrate as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate (NO3 as N) is 10.0 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-2/12/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130502
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(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 130502, Nitrogen, ammonia (Total Ammonia)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 232759
 
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: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Ammonia as N, Total.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Aquatic Life Ambient Water Quality Criteria for ammonia in freshwater are pH- and temperature-dependent and they are calculated as 30-day rolling average concentrations (criterion continuous concentration, CCC) of total ammonia nitrogen (in mg TAN/L) in freshwater is not to be exceed more than once every three years on average. (USEPA, 2013)
Guideline Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130502, Nitrogen, ammonia (Total Ammonia)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226439
 
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: SWAMP data indicates that 0 of the sample results exceed the evaluation guideline value for Ammonia as N, Total.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The U.S. EPA 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. (EPA 822-R-06-013, 2006).
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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130502, Nitrogen, ammonia (Total Ammonia)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 232778
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 42
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water samples were collected from Del Puerto Creek under the Irrigated Lands Regulatory Program. One of 42 samples exceeded the calculated ammonia CMC value.
Data Reference: Data for Various Pollutants in Southern San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Per the National Recommended Water Quality Criteria (USEPA 2006): The 1-hour average concentration (acute criterion or CMC) of total ammonia nitrogen (in mg N/L) for freshwater where salmonid fish are present, which is not to be exceeded more than once every three years on average, is calculated using the following equation: CMC=0.275/(1+10^(7.204 - pH)) + 39.0/(1+10^(pH - 7.204)).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Water samples were collected from two monitoring sites on Del Puerto Creek [Del Puerto Creek near Cox Road - 541XDPCCR and Del Puerto Creek @ Hwy 33 - 541STC523]
Temporal Representation: Water samples were collected approximately monthly between 7/11/2006 and 8/11/2009
Environmental Conditions:
QAPP Information: Sampling and analysis were done under a QAPP for the Irrigated Lands Regulatory Program (West Side Water Quality Coalition)
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130583
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Oxamyl (Vydate)
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130583, Oxamyl (Vydate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226864
 
Pollutant: Oxamyl (Vydate)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130583, Oxamyl (Vydate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226734
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130583, Oxamyl (Vydate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226733
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130583, Oxamyl (Vydate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226620
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Oxamyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: Waters designated for use as domestic or
municipal supply (MUN) shall not contain concentrations of pesticides in excess of the Maximum Contaminant Levels set forth in California Code of Regulations, Title 22, Division 4, Chapter 15. The California Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan is 50 ug/L. "
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-2/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130583, Oxamyl (Vydate)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226865
 
Pollutant: Oxamyl (Vydate)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130532
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2020)
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.

13 lines of evidence are available in the administrative record to assess this pollutant. One of the 107 samples exceeded the criteria for WARM (fraction- total). 3 of the 256 samples exceeded the objective for WARM (fraction - dissolved).

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. 13 lines of evidence are available in the administrative record to assess this pollutant. One of the 107 samples exceeded the criteria for WARM (fraction- total). 3 of the 256 samples exceeded the objective for WARM (fraction - dissolved). 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: This decision was made by SWRCB staff.
 
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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226496
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 61
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Sixty-one samples were taken from Del Puerto Creek between 2004 and 2006. One of the sixty-one samples falls below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226497
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 162
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-hundred-sixty-two samples were taken from Del Puerto Creek between 2001 and 2005. One of the one-hundred- sixty-two samples fall below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard, Deer Creek, Rogers, Del Puerto Mile 3.9, Del Puerto Mile 13.6 and Highway 33 in Stanislaus County.
Temporal Representation: Samples were collected between June 2001 and November 2005. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228398
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228404
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228399
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC527)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2010-09-07
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228435
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 10 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCHW)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2017-01-10
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228431
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC525)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 232741
 
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: SWAMP data indicates that 0 of the sample results exceed the criterion for Oxygen, Dissolved.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 232739
 
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: Statewide Ref Condition Management Plan 2008
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226582
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 31
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data to determine beneficial use support: One of 31 sample results exceed the criterion for Oxygen, Dissolved.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at two monitoring sites [Del Puerto Creek @ Hwy 33-541STC523 and Del Puerto Creek near Cox Road-541XDPCCR].
Temporal Representation: Data was collected approximately monthly between 1/9/2007 and 8/11/2009. Three pairs of samples were collected within 7-day periods; the sample results were averaged for each pair.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228401
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm 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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 8 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228403
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek (Stanislaus County) 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, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2015-07-15 and 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130532, Oxygen, Dissolved
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 228432
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 83
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 83 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as WARM is 5.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2017-08-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130600
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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 130600, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226796
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130598
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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 130598, PCBs (Polychlorinated biphenyls)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226789
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Total PCBs from MacDonald et al., 2000a which states that the probable effect concentration for Total PCBs is 676 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130584
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Paraquat
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)(2020)
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 130584, Paraquat
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226971
 
Pollutant: Paraquat
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Paraquat. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2006-07-11 to 2007-05-08
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130584, Paraquat
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226850
 
Pollutant: Paraquat
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 ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Paraquat. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2006-07-11 to 2007-07-10
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130584, Paraquat
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226621
 
Pollutant: Paraquat
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Paraquat.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: 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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for paraquat is the median effective concentration (EC50) 1200 ug/L.  (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-7/10/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130564
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Parathion
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)(2020)
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 130564, Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226587
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The NAS health advisory level for parathion or ethyl parathion is 30 µg/L.
Guideline Reference: National Academy of Sciences - Volume I Drinking Water and Health
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130564, Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226735
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek 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 53 samples were collected, 53 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130564, Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226866
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) 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 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 5.
 
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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130564, Parathion
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226588
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Ethyl.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA national ambient water quality chronic criterion (4-hour maximum) for parathion, is 0.013 µg/L, is for freshwater aquatic life.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130565
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Pendimethalin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130565, Pendimethalin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226589
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceed the criterion for Pendimethalin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Pendimethalin, 5.4 ug/L, is the EC50 for Selenastrun capricornutum (Green algae). USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/8/2008-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130565, Pendimethalin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226868
 
Pollutant: Pendimethalin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Pendimethalin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130565, Pendimethalin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226736
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 52
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 52 samples exceeded the water quality threshold for Pendimethalin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Pendimethalin is the USEPA Aquatic Life Benchmark of 5.2 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130565, Pendimethalin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226622
 
Pollutant: Pendimethalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 39
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 39 samples exceed the criterion for pendimethalin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: 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 California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for pendimethalin is the EC50 5.4 ug/L.  (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/6/2004-8/11/2009. The results for samples collected within a 7-day period were averaged before they were assessed.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130538
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226643
 
Pollutant: Permethrin
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 Codes: 541STC516).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2014-07-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226595
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Water Board staff assessed DPR data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for permethrin, total. One additional sample was not used in the assessment because the OC-normalized laboratory data reporting limit was above the objective, the available sample was below the laboratory data reporting limit, and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline value for permethrin in sediment (0.89 ug/g OC), is one-tenth of the geometric mean (8.9 ug/g OC) of the organic carbon-normalized (OC) LC50 values for Hyalella azteca, an amphipod crustacean. The LC50 values were derived by 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: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226794
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-22 to 2016-08-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226793
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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): 541XDPCCR.
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2017-09-11
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226646
 
Pollutant: Permethrin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
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. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 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
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 2 (Station Codes: 541XDPCCR, 541XDPCHW).
Temporal Representation: Data for this waterbody were collected over the date range 2010-09-13 to 2015-09-14
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226513
 
Pollutant: Permethrin
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: A total of 17 individual sediment samples were collected; 17 samples were below both the reporting limit (1.12 - 3.51 ug/kg dry weight) and the organic carbon normalized evaluation guideline (0.89 ug/g OC) and could not be quantified with the level of certainty required by the listing policy. 0 of 0 samples exceeded the evaluation guideline.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: The narrative objective for pesticides states, "No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for permethrin, 0.89 ug/g, is one-tenth of the median lethal concentration (LC50; 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: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s): Quality Assurance Project Plan for Pyrethroid Working Group.
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226590
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Nine samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Permethrin, 0.0002 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130538, Permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226594
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: The eleven samples collected did not exceed the water quality objective for permeathrin, thought to be protective of human health.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the Sacramento River and San Joaquin River Basins.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Drinking Water Health Advisories SNARL for non-cancer health efffects, USEPA IRIS Reference Dose (RfD) as a drinking water level for Permeathrin 350 ug/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: The samples were collected from Del Puerto Creek at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: No environmental conditions were reported.
QAPP Information: The recovery of spiked laboratory control samples from pyrethroid-analyzed water samples was outside of the control limits in 7% of the analyses. In most cases, exceedances were due to low recoveries of the pyrethroids, which could have led to underreporting of the pyrethroids in water samples. In addition, 9% of the laboratory duplicates were outside of the RPD control limit.
QAPP Information Reference(s):
 
 
DECISION ID
130603
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Phenanthrene
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)(2020)
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 130603, Phenanthrene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226800
 
Pollutant: Phenanthrene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Phenanthrene from MacDonald et al., 2000a which states that the probable effect concentration for Phenanthrene is 1170 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130568
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Phorate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130568, Phorate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226849
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 21 samples exceeded the water quality threshold for Phorate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130568, Phorate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226869
 
Pollutant: Phorate
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130568, Phorate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226972
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm 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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Phorate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130568, Phorate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226739
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130568, Phorate
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226596
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Phorate.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for phorate, 0.2 ug/L, is one-tenth of the median lethal concentration (LC50 = 2.0 ug/L) for Lepomis macrochirus (Bluegill sunfish). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130571
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Phosmet
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130571, Phosmet
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226973
 
Pollutant: Phosmet
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Phosmet.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130571, Phosmet
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226870
 
Pollutant: Phosmet
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130571, Phosmet
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226848
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Phosmet.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130571, Phosmet
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226740
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130571, Phosmet
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226603
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Phosmet.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Phosmet, 5.6 ug/L, is the EC50 for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130604
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Pyrene
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)(2020)
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 130604, Pyrene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226802
 
Pollutant: Pyrene
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 Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Pyrene is 1520 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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2010-07-08
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130527
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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. One of the 71 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for Warm Freshwater Habitat. Zero of the 64 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for Municipal & Domestic Supply.

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. One of the 71 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for Warm Freshwater Habitat. Zero of the 64 samples, reported as a total concentration or with the fraction not reported, exceeded the objective for Municipal & Domestic Supply. 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 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226741
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 5 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226738
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226605
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for selenium 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226604
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226475
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected one sample on 30 October 2002.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
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
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: A Sample was collected at Del Puerto Creek at Vineyard Rd
Temporal Representation: This was a one-time sampling event.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226474
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: The Westside San Joaquin River Water Quality Coalition collected six samples from 1 July 2006 to 31 October 2006. One out of the six samples collected exceeded the evaluation objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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: Samples were collected at two sites: Del Puerto Creek at Highway 33 and Del Puerto Creek Near Cox Road.
Temporal Representation: Monthly sampling occurred during the irrigation season.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226871
 
Pollutant: Selenium
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130527, Selenium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226872
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 5 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130524
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Simazine
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)(2020)
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.

Twelve lines of evidence are available in the administrative record to assess this pollutant for Municipal and Domestic Supply (MUN) and Warm Freshwater Habitat (WARM). One of the 159 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 85 samples, reported as a total concentration, exceed the guideline for WARM.

LOE 62559 has been replaced by LOE 222428 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

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. One of the 159 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. Zero of the 85 samples, reported as a total concentration, exceed the guideline for WARM. 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 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226950
 
Pollutant: Simazine
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226974
 
Pollutant: Simazine
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Simazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-12-29 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226949
 
Pollutant: Simazine
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226876
 
Pollutant: Simazine
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 DWR data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Simazine.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, and Pesticides in Regions 2,5 and 6, 2004-2010.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (DMC06715)
Temporal Representation: The samples were collected between the dates of 2005-03-16 and 2006-03-15
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan for Bryte Chemical Laboratory
QAPP Information Reference(s): Quality Assurance Project Plan from Bryte Chemical Laboratory.
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226851
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Simazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226743
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226742
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 53 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226606
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Simazine.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Simazine is 4 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226483
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 concentrations.0 of 19 available concentrations exceeded MCL (4 ug/L)
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road
Temporal Representation: Samples were collected at variable intervals (weekly and biweekly) from March to August 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226482
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 19 concentrations.0 of 19 available concentrations exceeded the MCL (4 ug/L).
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.
The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: Samples were collected daily during two storms in February and March 2003.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226466
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 9 water samples were collected from Del Puerto Creek from January through August 2006, representing 9 concentrations. 1 of 9 concentrations exceeded MCL (4 ug/L).
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and Cox Road.
Temporal Representation: One sample was collected in January 2005, and the other samples were collected monthly from January through August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130524, Simazine
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226465
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 34
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 34 water samples were collected from Del Puerto Creek from January 2000 through August 2001, representing 34 concentrations.0 of 34 concentrations exceeded the MCLs for drinking water standard (4 ug/L)
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. several samples per day, daily, and weekly) from January 2000 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
 
DECISION ID
130507
Region 5     
Del Puerto Creek (Stanislaus County)
 
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 130507, Sulfates
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226450
 
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: SWAMP data indicates that 0 of the sample results exceed the criterion for Sulfate.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Levels for sulfate provide a range of values including a recommended level (250 mg/L), an upper level (500 mg/L) and a short-term level (600 mg/L). The recommended level of 250 mg/L was used as it is intended to be protective of all drinking water uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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
130607
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Thiobencarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
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 130607, Thiobencarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226853
 
Pollutant: Thiobencarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2006-07-11 and 2007-08-14
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130607, Thiobencarb
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226975
 
Pollutant: Thiobencarb
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-12-29 and 2007-05-08
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130531
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Thiobencarb/Bolero
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130531, Thiobencarb/Bolero
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226485
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 5 water samples were collected from Del Puerto Creek from January 2005 through August 2006, representing 5 concentrations. 0 of 5 concentrations exceeded Secondary MCL concentration of 1 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline: Secondary Maximum Contaminate Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 ug/L (CDPH, 2008).
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected at variable intervals from January 2005 to August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130531, Thiobencarb/Bolero
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226486
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 29
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 29 water samples were collected from Del Puerto Creek from January 2000 through August 2001, representing 29 concentrations. 0 of 29 concentrations exceeded Secondary MCL concentration of 1 ug/L.
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Secondary Maximum Contaminate Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 ug/L (CDPH, 2008).
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: Samples were collected at variable intervals (e.g. daily, weekly) from January 2000 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130531, Thiobencarb/Bolero
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226524
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Thiobencarb, 1.4 ug/L, is a maximum acceptable toxicicant concentration (MATC) calculated for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130531, Thiobencarb/Bolero
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226525
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of Thiobencarb in excess of 1.0 µg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/14/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130543
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Toxaphene
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)(2020)
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 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 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 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226953
 
Pollutant: Toxaphene
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226952
 
Pollutant: Toxaphene
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from the consumption of water and organisms is 0.00073 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 (541STC523).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226527
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion for the protection of human health from the consumption of water and organisms is 0.00073 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226526
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Toxaphene.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 ug/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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226747
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from consumption of organisms only is 0.00075 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226744
 
Pollutant: Toxaphene
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criteria for the protection of human health from the consumption of water and organisms is 0.00073 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130543, Toxaphene
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226745
 
Pollutant: Toxaphene
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Toxaphene. Although a total of 55 samples were collected, 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Toxaphene criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.0002 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 (541XDPCCR).
Temporal Representation: Date for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130530
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Trifluralin
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)(2020)
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 for Warm Freshwater Habitat (WARM). Six of the 168 samples exceed the guideline for WARM.

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. Six of the 168 samples exceed the guideline for WARM 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 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226954
 
Pollutant: Trifluralin
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226976
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
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 ILRP_WSWQC data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-02-18
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226750
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 51
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 51 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226509
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 27 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from July 2004 through June 2006 representing 27 concentrations.2 of 27 concentrations exceeded the maximum concentration of 0.70 ug/L.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Samples were collected from Del Puerto Creek near Highway 33 and Cox Road Near Patterson, CA.
Temporal Representation: Samples were collected at variable intervals (biweekly, weekly, monthly) from July 2004 through June 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226508
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 34
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 34 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from June 1994 through August 2001 representing 34 concentrations.2 of 34 concentrations exceeded the maximum concentration of 0.70 ug/L.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road Near Patterson, CA.
Temporal Representation: Samples were collected during two storms in February 2000 and June 2001, and at variable intervals (biweekly, weekly, monthly) from June 1994 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226507
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 33 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from January 2000 through August 2001 representing 33 concentrations.2 of 33 concentrations exceeded the maximum concentration of 0.70 ug/L.
Data Reference: Report and data files for pesticides in the Sacramento River, Winter 2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road Near Patterson, CA.
Temporal Representation: Samples were collected during one storm in February 2000 and at variable intervals (biweekly, weekly, monthly) from January 2000 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226484
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: 2 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from February 2006 through March 2006 representing 2 concentrations.0 of 2 concentrations exceeded the maximum concentration of 0.70 ug/L.
Data Reference: Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
 
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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference: Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road near Patterson, CA.
Temporal Representation: Samples were collected at variable intervals (biweekly, weekly, monthly) from February 2006 through March 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
 
Line of Evidence (LOE) for Decision ID 130530, Trifluralin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226852
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_WSWQC data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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 Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2004-07-06 and 2009-08-11
Environmental Conditions:
QAPP Information: Data was previously assessed without a QAPP. Data reassessed without a QAPP for consistency. Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s): This is a placeholder for previously assessed data that does not have quality assurance information but would require it under newly developed policies. These LOEs were previously assessed and approved at the Regional, State and Federal level in past cycles. The LOEs needed to be moved and/or reassessed but required this reference code for movement within the decision making database.
 
 
DECISION ID
130522
Region 5     
Del Puerto Creek (Stanislaus County)
 
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226462
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for Zinc
Data Reference: San Joaquin River SWAMP Monitoring Data - Westside Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved Zinc levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978)
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: Samples were collected from Del Puerto Creek at Vineyard Avenue
Temporal Representation: The samples were collected from November 29, 2000, to October 30, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226748
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226749
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226751
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226956
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226532
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 AgWaiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The 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 metals criteria.
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 Del Puerto Creek was collected at 1 monitoring site [ Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 4/14/2009-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226536
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for zinc is 5.0 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226955
 
Pollutant: Zinc
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226957
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130522, Zinc
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226801
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Zinc from MacDonald et al., 2000a which states that the probable effect concentration for Zinc is 459 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
130578
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226691
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan I criteria for the protection of human health from consumption of organisms only is 240 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226615
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endosulfan I.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule criteria for Endosulfan I to protect human health for waters that include the designated use of MUN is 110 ug/L.
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226690
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 54 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226925
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The alpha-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226696
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 53 samples exceeded the water quality threshold for Endosulfan I. Although a total of 54 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130578, alpha-Endosulfan (Endosulfan 1)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226926
 
Pollutant: alpha-Endosulfan (Endosulfan 1)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan I.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan I criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130582
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130582, alpha.-BHC (Benzenehexachloride or alpha-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226619
 
Pollutant: alpha.-BHC (Benzenehexachloride or alpha-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, alpha.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The BHC, alpha criteria for the protection of human health from the consumption of water and organisms is 0.0039 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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130566
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: beta-BHC (Benzenehexachloride or beta-HCH)
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.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the twenty samples exceed the criteria.

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 twenty samples exceed the criteria 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 130566, beta-BHC (Benzenehexachloride or beta-HCH)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226592
 
Pollutant: beta-BHC (Benzenehexachloride or beta-HCH)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for HCH, beta.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The HCH, beta criterion for the protection of human health from the consumption of water and organisms is 0.014 ug/L (California Toxics Rule, 2002).
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130579
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: beta-Endosulfan (Endosulfan 2)
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)(2020)
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.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226692
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endosulfan II criteria for the protection of human health from consumption of organisms only is 240 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226927
 
Pollutant: beta-Endosulfan (Endosulfan 2)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The beta-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226699
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 55 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The beta-endosulfan criteria for the protection of human health from the consumption of water and organisms is 110 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 (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226930
 
Pollutant: beta-Endosulfan (Endosulfan 2)
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 Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Endosulfan II.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 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 (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226616
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 20 samples exceed the criterion for Endosulfan II.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule criteria for Endosulfan II to protect human health for waters that include the designated use of MUN is 110 ug/L.
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: Data for this line of evidence for Del Puerto Creek was collected at 2 monitoring sites [ Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 2/11/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130579, beta-Endosulfan (Endosulfan 2)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226698
 
Pollutant: beta-Endosulfan (Endosulfan 2)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and the results are as follows: 0 of the 54 samples exceeded the water quality threshold for Endosulfan II. Although a total of 55 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 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The endosulfan II criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.028 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 (541XDPCCR).
Temporal Representation: Data for this waterbody was collected over the date range 2010-12-20 to 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130523
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: cis-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: 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. One of the thirty-five samples exceed the evaluation guideline.

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. One of thirty-five samples exceeded the evaluation guideline 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 130523, cis-permethrin
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226463
 
Pollutant: cis-permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Thirty-five water samples were collected from Del Puerto Creek from October 1992 through August 2001 representing 35 concentrations. One sample had a concentrations less than the quantitation limit, and the quantitation limit that is greater than the Evaluation Guideline and, therefore, this sample was not used in this assessment, in accordance with section 6.1.5.5 of the Listing Policy.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
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 (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 24-hour LC50 for cis-permethrin, for the most sensitive species (Tanytarsus sp., a midge) is 0.033 ug/L. Therefore, the one-tenth LC50 value for the cis-permethrin Evaluation Guideline is 0.0033 ug/L.
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Guideline Reference: ECOTOX database, aquatic data. U. S. Environmental Protection Agency
 
Spatial Representation: Samples were collected from Del Puerto Creek at Vineyard Road, near Patterson.
Temporal Representation: Samples were collected at variable intervals (biweekly, weekly, monthly) from October 1992 through August 2001.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
 
DECISION ID
130574
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: p,p'-DDD (Dichlorodiphenyldichloroethane)
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 130574, p,p'-DDD (Dichlorodiphenyldichloroethane)
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226609
 
Pollutant: p,p'-DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support.
None of the 24 samples results were detected at levels above reporting limits limits of 0.01 or 0.003 ug/L. Since the reporting limits were greater than the criterion, none of the samples were assessed.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The CTR objective for DDD(p,p') to protect human health from the consumption of water and organisms is 0.00083 ug/L.
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 Del Puerto Creek was collected at 2 monitoring sites: [five samples were collected from Del Puerto Creek @ Hwy 33 - 541STC523, and 19 samples were collected from Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 7/11/2006-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130585
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Boron
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Decision in Progress(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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 for Agricultural Supply (AGR). Eleven of the 37 samples exceed the guideline for AGR.

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. Eleven of the 37 samples exceed the guideline for AGR 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 130585, Boron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226659
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 33
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek to determine beneficial use support and results are as follows: 10 of 33 samples exceeded the water quality threshold for Boron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2018-02-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130585, Boron
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226900
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 4 samples exceeded the water quality threshold for Boron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-12-20 and 2011-04-12
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130597
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Chromium
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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.

Ten lines of evidence is available in the administrative record to assess this pollutant for Warm Freshwater Habitat (WARM). Three of the five samples exceed the pollutant guideline for WARM. Fifty-seven of the 78 sediment toxicity samples exceed the objective for WARM.

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. Three of the five samples exceed the guideline for WARM. Fifty-seven of the 78 sediment toxicity samples exceed the objective for WARM 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 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226531
 
Pollutant: Toxicity
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of nine sediment samples from DPC caused 100% mortality to H. azteca. The December storm sample caused almost 80% mortality. From calculated TUs, bifenthrin was the major contributor of toxicity at DPC. Except for the December sample, bifenthrin was detected in every sediment sample at this creek, containing between 1.5 and 15 TUs. Cyfluthrin, ë-cyhalothrin and esfenvalerate were also detected at DPC, but only ë-cyhalothrin would have contributed to toxicity, with between 0.6 to 1.8 TUs. Cyfluthrin and esfenvalerate contributed a minor amount, less than 0.5 TUs.
Data Reference: Data for Pyrethroids from Del Puerto Creek and Orestimba Creeks, 2006.
 
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. There shall be no increase in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected from Del Puerto Creek (DPC) at the intersection of Vineyard Ave. near the town of Patterson.
Temporal Representation: Water and sediment samples were collected monthly from December 2007 through June 2008. In December, January, and February, one additional sample per month was collected during a rain event.
Environmental Conditions: Three of the ten sample events occurred after a storm event.
QAPP Information: For pyrethroids in sediments, quality control consisted of two surrogates, method blanks, laboratory control samples, laboratory control sample duplicates, matrix spikes, and matrix spike duplicates. In addition, 5% of the field samples were field duplicates. QA/QC for toxicity testing comprised of field duplicates (10%) and field blanks (5%).
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226631
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 4 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Survival, Hyalella azteca, for Growth (wt/surv indiv)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Stream Pollution Trends
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 stations. Monitoring site(s): ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2011-07-22 and 2014-07-09.
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program  
QAPP Information Reference(s): Quality Assurance Program Plan for the Statewide Stream Pollution Trends Monitoring Program
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226753
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 9 of the 9 samples collected by SWAMP Stream Pollution Trends for Del Puerto Creek 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: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
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 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 541STC516 )
Temporal Representation: The samples were collected between the dates of 2010-07-08 and 2018-08-23.
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226488
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: Samples were collected from September 2004 to September 2006.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226489
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: Samples were collected from October 2001 to October 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226766
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
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 SWAMP Stream Pollution Trends data for Del Puerto Creek to determine beneficial use support and the results are as follows: 3 of the 5 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin) 
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for Chromium from MacDonald et al., 2000a which states that the probable effect concentration for Chromium is 111 mg/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): 541STC516.
Temporal Representation: Data for this waterbody were collected over the date range 2010-07-08 to 2018-08-23
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226452
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: Toxicity testing of sediments
Data Used to Assess Water Quality: Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at:
-Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003
-Del Puerto Creek at Hwy 33 on 10/28/2002
-Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002
-note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226518
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 11
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Fifteen samples were collected to evaluate sediment toxicity. Eleven of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. 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: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
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. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
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 using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Del Puerto Creek at Hwy 33 and Del Puerto Creek near Cox Road.
Temporal Representation: The samples were collected from March 2005 to March 2009.
Environmental Conditions:
QAPP Information: Collected under the Monitoring and Reporting Program Plans for the Westside Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226516
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One-tenth the organic carbon normalized LC50 values for sediment-bound pyrethroids were used as toxicity thresholds in a toxicity unit (TU) analysis. Samples containing at least 2 pyrethroids with concentrations above the reporting limit were assessed for additive toxicity. 5 of 7 sediment samples indicated a calculated TU > 1, suggesting that samples had pyrethroid pesticides at levels expected to exert additive, chronic toxicity. A combination of 2 or more of the pyrethroids, bifenthrin, lambda-cyhalothrin, and esfenvalerate were present in the assessed samples.
Data Reference: Various Data for Pleasant Grove Creek, Del Puerto Creek and Roseville Area, 2006-2010.
 
SWAMP Data:
 
Water Quality Objective/Criterion: "The narrative toxicity objective states, ""All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances."
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The evaluation guideline for the TU analysis is based on the following: "The concentration of each toxic substance is divided by its toxicologic limit. The resulting ratios are added for substances having similar toxicologic effects and, separately, for carcinogens. The additive toxicity criterion has been violated if the sum of the ratios is >1 (CV Basin Plan, 2011)."
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: 8 sediment samples were representative of non-depositional areas and 9 sediment samples representative of depositional areas. Sites 5847m-D and 5987m-D were not considered separate sites; results for these locations were averaged since they are within 200 m of each other and both considered depositional.
Temporal Representation: Sediment samples were collected on 03/28/2010
Environmental Conditions:
QAPP Information: Submitted QA data are acceptable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 130597, Chromium
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226632
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 4 of the 15 samples collected by Westside San Joaquin River Watershed Coalition for Del Puerto Creek 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: Hyalella azteca, for Survival
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Westside San Joaquin River Watershed Coalition
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 stations. Monitoring site(s): ( 541STC523, 541XDPCCR, 541XDPCHW )
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2015-09-14.
Environmental Conditions:
QAPP Information: Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board  
QAPP Information Reference(s): Westside San Joaquin River Watershed Coalition Quality Assurance Project Plan For Monitoring Designed for the Irrigated Lands Regulatory Program Central Valley Regional Water Quality Control Board
 
 
DECISION ID
130504
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Specific Conductivity
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.

10 lines of evidence are available in the administrative record to assess this pollutant. 75 of the 132 samples exceed the OBJECTIVE for MUN.

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. 75 of the 132 samples exceeded the OBJECTIVE for MUN 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: This decision was made by SWRCB staff.
 
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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 230056
 
Pollutant: Specific Conductivity
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 SWAMP Stream Pollution Trends data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 4 of 5 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2013-07-10 and 2017-07-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 230104
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229891
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 7 of 10 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCHW)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2017-01-10
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
 
DECISION ID
130605
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Specific Conductivity
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2020)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
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.

Nine lines of evidence are available in the administrative record to assess this pollutant for Municipal and Domestic Supply. 24 of the 35 samples, reported as a total concentration, exceed the objective for Municipal and Domestic Supply. 16 of the 35 samples, reported in the unknown fraction, exceed the objective for Municipal and Domestic Supply.

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. 24 of the 35 samples, reported as a total concentration, exceed the objective for Municipal and Domestic Supply. 16 of the 35 samples, reported in the unknown fraction, exceed the objective for Municipal and Domestic Supply 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:
 
 
Line of Evidence (LOE) for Decision ID 130605, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226441
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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: SWAMP data indicates that the sample result exceeds the criterion for electrical conductivity.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130605, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226546
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 34
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 15 of 34 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130504
Region 5     
Del Puerto Creek (Stanislaus County)
 
Pollutant: Specific Conductivity
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.

10 lines of evidence are available in the administrative record to assess this pollutant. 75 of the 132 samples exceed the OBJECTIVE for MUN.

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. 75 of the 132 samples exceeded the OBJECTIVE for MUN 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: This decision was made by SWRCB staff.
 
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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226441
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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: SWAMP data indicates that the sample result exceeds the criterion for electrical conductivity.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 230044
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 1 of 7 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC523)
Temporal Representation: The samples were collected between the dates of 2010-09-13 and 2012-03-13
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229890
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 71
Number of Exceedances: 43
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Westside San Joaquin River Watershed Coalition data for Del Puerto Creek (Stanislaus County) to determine beneficial use support and results are as follows: 43 of 71 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541XDPCCR)
Temporal Representation: The samples were collected between the dates of 2010-09-16 and 2017-08-08
Environmental Conditions:
QAPP Information: Pacific EcoRisk. 2013. QAPP for Westside San Joaquin River Watershed Coalition.
QAPP Information Reference(s): QAPP for Westside San Joaquin River Watershed Coalition
 
Line of Evidence (LOE) for Decision ID 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 230009
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC527)
Temporal Representation: The samples were collected between the dates of 2010-09-07 and 2010-09-07
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229744
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (541STC516)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 229318
 
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 SWAMP RWB5 Monitoring data for Del Puerto Creek (Stanislaus County) 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, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (542STC525)
Temporal Representation: The samples were collected between the dates of 2010-10-21 and 2010-10-21
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
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 130504, Specific Conductivity
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226546
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 34
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 15 of 34 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-8/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
130561
Region 5     
Del Puerto Creek (Stanislaus County)
 
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 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 is available in the administrative record to assess this pollutant. Zero of the seventeen samples exceed the criteria.

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 sixteen samples exceed the criteria 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 130561, Nitrogen, Nitrite
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226444
 
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: SWAMP data indicates that 0 of the sample results exceed the criterion for Nitrite as N.
Data Reference: Statewide Ref Condition Management Plan 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nitrite (as N) is 1,000 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
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 was collected at one monitoring site [ Del Puerto Creek - 542DPCDPC]
Temporal Representation: Data was collected on 6/18/2008.
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 130561, Nitrogen, Nitrite
Region 5     
Del Puerto Creek (Stanislaus County)
 
LOE ID: 226581
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 Ag Waiver data for Del Puerto Creek to determine beneficial use support and results are as follows: 0 of 16 samples exceed the criterion for Nitrite as N.
Data Reference: Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrite (as N) is 1 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 Del Puerto Creek was collected at 2 monitoring sites [Del Puerto Creek @ Hwy 33 - 541STC523, Del Puerto Creek near Cox Road - 541XDPCCR]
Temporal Representation: Data was collected over the time period 1/9/2007-2/12/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):