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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name: Cordellia Slough, unnamed tributary
Water Body ID: CAR2072104020110629225459
Water Body Type: River & Stream
 
DECISION ID
100848
Region 2     
Cordellia Slough, unnamed tributary
 
Pollutant: Mercury
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Historic Land Management Activities
TMDL Name: Suisun Marsh Dissolved Oxygen and Mercury TMDL
TMDL Project Code: 553
Date TMDL Approved by USEPA: 12/31/2018
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Cordellia Slough is part of the Suisun Marsh system. As such, the mercury and dissolved oxygen impairments for Suisun Marsh are applicable to sloughs within the marsh. Further, the TMDL for Suisun Marsh will resolve these impairments for sloughs within the Suisun Marsh system. Accordingly, the mercury impairment in Cordellia Slough will be addressed and resolved by the Suisun Marsh TMDL for dissolved oxygen approved by USEPA on 12/31/2018.
 
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 100848, Mercury
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 125243
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: This is a placeholder LOE to allow Cordellia Slough mercury impairment to be associated with the TMDL for Suisun Marsh
Data Reference: Staff Report for Proposed Basin Plan Amendment - Establish Water Quality Objectives and a Total Maximum Daily Load for Dissolved Oxygen in Suisun Marsh and add Suisun Marsh to the SF Bay Mercury TMDL
 
SWAMP Data:
 
Water Quality Objective/Criterion: This is a placeholder LOE to allow Cordellia Slough mercury impairment to be associated with the TMDL for Suisun Marsh. This placeholder LOE will fulfill database requirements to create a listing for Cordellia Slough. This slough listing will subsequently be associated with the TMDL for Suisun Marsh - which aims to resolve the mercury and low DO/organic enrichment impairments. Cordellia Slough is part of the Suisun Marsh system so resolution of the Suisun Marsh impairments will resolve those in Cordellia Slough as well.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: This is a placeholder LOE to allow Cordellia Slough mercury impairment to be associated with the TMDL for Suisun Marsh.
QAPP Information Reference(s):
 
 
DECISION ID
94892
Region 2     
Cordellia Slough, unnamed tributary
 
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)(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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 94892, Chlordane
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 90719
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 samples collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the San Francisco Bay Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 207SUP102 (Suisun Slough Tributary).
Temporal Representation: The samples were collected on 1/3/2007.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
94893
Region 2     
Cordellia Slough, unnamed tributary
 
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)(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 one samples exceed the 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.

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 guideline 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 94893, DDD (Dichlorodiphenyldichloroethane)
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91365
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
94792
Region 2     
Cordellia Slough, unnamed tributary
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 94792, DDE (Dichlorodiphenyldichloroethylene)
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91366
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
91993
Region 2     
Cordellia Slough, unnamed tributary
 
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)(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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 91993, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91371
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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 91993, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91367
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
94793
Region 2     
Cordellia Slough, unnamed tributary
 
Pollutant: Dieldrin
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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 94793, Dieldrin
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91368
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
94734
Region 2     
Cordellia Slough, unnamed tributary
 
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)(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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 94734, Endrin
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91369
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
100190
Region 2     
Cordellia Slough, unnamed tributary
 
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)(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 3.6 of the Listing Policy.
Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant
concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

One line of evidence is available in the administrative record to assess this pollutant. Zero of one samples exceed the guideline.
Sediment toxicity data are not relevant to this decision because there is not enough information based on sediment chemistry.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one samples exceed the objective and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
Sediment toxicity data are not associated with this decision because the sediment chemistry data are insufficient.
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 100190, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 91370
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Cordellia Slough, unnamed tributary to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Cordellia Slough, unnamed tributary was collected at 1 monitoring site [ Suisun Slough Tributary station (207SUP102).]
Temporal Representation: Data was collected on a single day 1/3/2007.
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): 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
94853
Region 2     
Cordellia Slough, unnamed tributary
 
Pollutant: Toxicity
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 3.6 of the Listing Policy.
Under section 3.6 just one line of evidence is necessary to assess listing status for sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

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

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of one samples exceed the guideline and this sample size is insufficient to determine beneficial use support, with the power and confidence of the Listing Policy. 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 94853, Toxicity
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 90508
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample exhibited significant toxicity. The toxicity test included survival and growth 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: Statewide Project Urban Pyrethroid Status Monitoring
 
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 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
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: 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 sample was collected at station 207SUP102.
Temporal Representation: The sample was collected in January 2007.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
100849
Region 2     
Cordellia Slough, unnamed tributary
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Original
Sources: A Source Unknown
TMDL Name: Suisun Marsh Dissolved Oxygen and Mercury TMDL
TMDL Project Code: 553
Date TMDL Approved by USEPA: 12/31/2018
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Cordellia Slough is part of the Suisun Marsh system. As such, the impairments for Suisun Marsh are applicable to sloughs within the marsh. Further, the TMDL for Suisun Marsh will resolve the impairments for sloughs within the Suisun Marsh system. Accordingly, the dissolved oxygen impairment in Cordellia Slough will be addressed and resolved by the Suisun Marsh TMDL for dissolved oxygen approved by USEPA on 12/31/2018.
 
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 100849, Oxygen, Dissolved
Region 2     
Cordellia Slough, unnamed tributary
 
LOE ID: 125244
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: This is a placeholder LOE to allow Cordellia Slough dissolved oxygen impairment to be associated with the TMDL for Suisun Marsh
Data Reference: Staff Report for Proposed Basin Plan Amendment - Establish Water Quality Objectives and a Total Maximum Daily Load for Dissolved Oxygen in Suisun Marsh and add Suisun Marsh to the SF Bay Mercury TMDL
 
SWAMP Data:
 
Water Quality Objective/Criterion: This is a placeholder LOE to allow Cordellia Slough dissolved oxygen impairment to be associated with the TMDL for Suisun Marsh. This placeholder LOE will fulfill database requirements to create a listing for Cordellia Slough. This slough listing will subsequently be associated with the TMDL for Suisun Marsh - which aims to resolve the mercury and low DO/organic enrichment impairments. Cordellia Slough is part of the Suisun Marsh system so resolution of the Suisun Marsh impairments will resolve those in Cordellia Slough as well.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: This is a placeholder LOE to allow Cordellia Slough dissolved oxygen impairment to be associated with the TMDL for Suisun Marsh.
QAPP Information Reference(s):