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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Casa de Oro Creek
Water Body ID: CAR9091200020110812132234
Water Body Type: River & Stream
 
DECISION ID
82791
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. Zero of 15 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.

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 15 samples exceed the 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 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 82791, Cadmium
Region 9     
Casa de Oro Creek
 
LOE ID: 73150
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Cadmium.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Kenwood Drive and Barbic Court, Casa de Oro Creek @ Valencia Street/Kings View Circle]
Temporal Representation: Data was collected from 1/2/2003 through 1/16/2009.
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
82792
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One line of evidence are available in the administrative record to assess this pollutant. Zero of 0 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.

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 0 samples exceed the 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 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 82792, Chlorpyrifos
Region 9     
Casa de Oro Creek
 
LOE ID: 73151
 
Pollutant: Chlorpyrifos
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 County of San Diego data for Casa de Oro Creek 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Valencia Street/Kings View Circle, Casa de Oro Creek @ Kenwood Drive and Barbic Court]
Temporal Representation: Data was collected over the time period 9/26/2005-6/16/2009.
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
82793
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. One of 13 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.

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 13 samples exceed the 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 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 82793, Copper
Region 9     
Casa de Oro Creek
 
LOE ID: 73152
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 13 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Kenwood Drive and Barbic Court, Casa de Oro Creek @ Valencia Street/Kings View Circle]
Temporal Representation: Data was collected from 1/2/2003 through 1/16/2009.
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
82002
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. Zero of 9 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.

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 9 samples exceed the 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 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 82002, Diazinon
Region 9     
Casa de Oro Creek
 
LOE ID: 73153
 
Pollutant: Diazinon
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 County of San Diego data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 9 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Valencia Street/Kings View Circle, Casa de Oro Creek @ Kenwood Drive and Barbic Court]
Temporal Representation: Data was collected over the time period 9/26/2005-6/16/2009.
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
82003
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. One of 13 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.

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 13 samples exceed the 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 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 82003, Lead
Region 9     
Casa de Oro Creek
 
LOE ID: 73154
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for Lead.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Kenwood Drive and Barbic Court, Casa de Oro Creek @ Valencia Street/Kings View Circle]
Temporal Representation: Data was collected from 1/2/2003 through 1/16/2009.
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
82111
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. Zero of 9 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.

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 9 samples exceed the 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 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 82111, Malathion
Region 9     
Casa de Oro Creek
 
LOE ID: 73155
 
Pollutant: Malathion
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 County of San Diego data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 9 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Valencia Street/Kings View Circle, Casa de Oro Creek @ Kenwood Drive and Barbic Court]
Temporal Representation: Data was collected over the time period 9/26/2005-6/16/2009.
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
82166
Region 9     
Casa de Oro Creek
 
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(s) of evidence are necessary to assess listing status.

One lines of evidence are available in the administrative record to assess this pollutant. Zero of 13 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.

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 13 samples exceed the 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 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 82166, Zinc
Region 9     
Casa de Oro Creek
 
LOE ID: 73156
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for Casa de Oro Creek to determine beneficial use support and results are as follows: 0 of 13 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 Casa de Oro Creek was collected at 2 monitoring sites [ Casa de Oro Creek @ Kenwood Drive and Barbic Court, Casa de Oro Creek @ Valencia Street/Kings View Circle]
Temporal Representation: Data was collected from 1/2/2003 through 1/16/2009.
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.