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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: San Marcos, Lake, drain to central southeast fork of lake
Water Body ID: CAR9045200020110620113356
Water Body Type: River & Stream
 
DECISION ID
84026
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the Five samples exceed the Water Quality Criteria for Cadmium.

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 Five samples exceeded the Water Quality Criteria for Cadmium 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 84026, Cadmium
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76044
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 1 of 11 samples exceed the criterion for Cadmium.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring sites [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected 7/20/2004 - 6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
84027
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the Zero samples exceed the Water Quality Criteria for Chlorpyrifos.

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 Zero samples exceeded the Water Quality Criteria for Chlorpyrifos 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 84027, Chlorpyrifos
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76045
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Chlorpyrifos.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
84374
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. One of the Nine samples exceed the Water Quality Criteria for Copper.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of Nine samples exceeded the Water Quality Criteria for Copper 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 84374, Copper
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76047
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: Non-fixed station physical/chemical (conventional + toxicants)
Data Used to Assess Water Quality: One of the four samples exceeded the criteria of 9.3 ug/L.
Data Reference: Data for Various Pollutants in Region 9, 2002-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Inland surface waters, enclosed bays, and estuaries shall not contain toxic pollutants in excess of the numerical objectives applicable to California specified in 40 CFR 131.36 (section 131.36 revised at 57 FR 60848, December 22, 1992).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
Guideline 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
 
Spatial Representation: A sample was collected from the Central southeast fork at a station called CAR14.
Temporal Representation: Samples were collected annually in the summer months during the years: 2004 through 2008 (data from 2005 was not reported).
Environmental Conditions:
QAPP Information: The samples were collected and analyzed by the County of San Diego as part of their storm water program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 84374, Copper
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76046
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring sites [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected 7/20/2004 - 6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
84190
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
Pollutant: Diazinon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the Five samples exceed the Water Quality Criteria for Dizinon.

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 Five samples exceeded the Water Quality Criteria for Dazinon 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 84190, Diazinon
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76061
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Diazinon.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
100625
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.3 of the Listing Policy. Under section 3.3 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. Four of Five samples exceed the Water Quality Objective for Enterococcus, Three of the Five samples exceeded the water quality objective for Total Coliform.

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. Four of Five samples exceed the Water Quality Objective for Enterococcus, Three of the Five samples exceeded the water quality objective for Total Coliform 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 100625, Indicator Bacteria
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76062
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 4 of 5 samples exceed the criterion for Enterococci.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Samples shall not exceed 61 organisms per 100 ml for enterococcus in waters designated for REC I beneficial use (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 100625, Indicator Bacteria
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76079
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 4
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 4 of 5 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxicsubstances in concentrations which are toxic to,or which produce detrimental physiologicalresponses in human, plant, animal, or indigenousaquatic life (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In waters designated for water contact recreation (REC I), the total coliform concentration shall not exceed 10000 MPN/100 ml (CDPH 2006).
Guideline Reference: Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 100625, Indicator Bacteria
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76063
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 3 of 5 samples exceed the criterion for Coliform, Fecal.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In waters designated for water contact recreation (REC I), the fecal coliform concentration shall not exceed 400 MPN/100 ml.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
84424
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the Eight samples exceed the Water Quality Criteria for Lead.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the Eight samples exceed the Water Quality Criteria for Lead 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 84424, Lead
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76064
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring sites [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected 7/20/2004 - 6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 84424, Lead
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76065
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Non-fixed station physical/chemical (conventional + toxicants)
Data Used to Assess Water Quality: None of the three samples exceeded the criteria of 3.2 ug/L. One of the samples was reported as "ND" without a reporting limit, therefore this data was not used in the assessment.
Data Reference: Data for Various Pollutants in Region 9, 2002-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Inland surface waters, enclosed bays, and estuaries shall not contain toxic pollutants in excess of the numerical objectives applicable to California specified in 40 CFR 131.36 (section 131.36 revised at 57 FR 60848, December 22, 1992).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
Guideline 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
 
Spatial Representation: A sample was collected from the Central southeast fork at a station called CAR14.
Temporal Representation: Samples were collected annually in the summer months during the years: 2004 through 2008 (data from 2005 was not reported).
Environmental Conditions:
QAPP Information: The samples were collected and analyzed by the County of San Diego as part of their storm water program.
QAPP Information Reference(s):
 
 
DECISION ID
84158
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

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

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 Five samples exceeded the Water Quality Criteria for Malathion 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 84158, Malathion
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76078
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 5 samples exceed the criterion for Malathion.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring site [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected over the time period 7/20/2004-6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
84425
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence is available in the administrative record to assess this pollutant. Zero of the Eight samples exceed the Water Quality Criteria for Lead.

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 Eight samples exceeded the Water Quality Criteria for Lead 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 84425, Zinc
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76081
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Non-fixed station physical/chemical (conventional + toxicants)
Data Used to Assess Water Quality: None of the three samples exceeded the criteria of 120 ug/L. One of the samples was reported as "ND" without a reporting limit, therefore this data was not used in the assessment.
Data Reference: Data for Various Pollutants in Region 9, 2002-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Inland surface waters, enclosed bays, and estuaries shall not contain toxic pollutants in excess of the numerical objectives applicable to California specified in 40 CFR 131.36 (section 131.36 revised at 57 FR 60848, December 22, 1992).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) 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. If no hardness data were available, a value of 100 mg/L was used.
Guideline 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
 
Spatial Representation: A sample was collected from the Central southeast fork at a station called CAR14.
Temporal Representation: Samples were collected annually in the summer months during the years: 2004 through 2008 (data from 2005 was not reported).
Environmental Conditions:
QAPP Information: The samples were collected and analyzed by the County of San Diego as part of their storm water program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 84425, Zinc
Region 9     
San Marcos, Lake, drain to central southeast fork of lake
 
LOE ID: 76080
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Marcos, Lake, drain to central southeast fork of lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Marcos, Lake, drain to central southeast fork of lake was collected at 1 monitoring sites [ Tributary to Lake San Marcos @ End of El Chico Lane]
Temporal Representation: Data was collected 7/20/2004 - 6/11/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.