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

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name: Mad River HU, Duke Creek
Water Body ID: CAR1091003020171129037971
Water Body Type: River & Stream
 
DECISION ID
104821
Region 1     
Mad River HU, Duke Creek
 
Pollutant: Nitrogen, Nitrate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: "This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None of the fourteen samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 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 104821, Nitrogen, Nitrate
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120606
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality standard for Nitrate as N.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Water Quality Control Plan, North Coast Basin is 10.0 mg/L (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 2012-12-19 and 2016-12-12
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104821, Nitrogen, Nitrate
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120452
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality standard for Nitrate as N.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Water Quality Control Plan, North Coast Basin is 10.0 mg/L (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 2012-12-19 and 2016-12-12
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
104329
Region 1     
Mad River HU, Duke Creek
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant.
None of the 115 samples exceed the objective for the COLD beneficial use.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. None of the 115 samples exceed the objective for the COLD beneficial use and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120605
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 33
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 33 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 1/31/13 - 4/13/17.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120449
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for COLD beneficial use waters to be a daily minimum of 6.0 mg/L and a 7-day moving average of 8.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 7/26/12 to 10/31/12.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120441
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for COLD beneficial use waters to be a daily minimum of 6.0 mg/L and a 7-day moving average of 8.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 7/29/13 - 10/18/16.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120311
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for COLD beneficial use waters to be a daily minimum of 6.0 mg/L and a 7-day moving average of 8.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 7/26/12 - 10/31/12.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120309
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for COLD beneficial use waters to be a daily minimum of 6.0 mg/L and a 7-day moving average of 8.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 7/29/13 - 10/18/16.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120620
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 12/10/10, 6/20/12, 11/20/12, and 12/19/12.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120553
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected on 12/10/10 and 6/20/12.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104329, Oxygen, Dissolved
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120761
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples: 36
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 36 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 11/20/12 - 4/13/17.
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
104333
Region 1     
Mad River HU, Duke Creek
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant.
None of the samples exceed the objective for the MUN beneficial use(s).

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. None of the samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 104333, Specific Conductivity
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120378
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's \Chemical Constituents\" objective. The California Secondary MCL for specific conductivity is 900 uS/cm."
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 2012-08-21 and 2017-04-13
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104333, Specific Conductivity
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120315
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's \Chemical Constituents\" objective. The California Secondary MCL for specific conductivity is 900 uS/cm."
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 2010-12-10 and 2012-07-26
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104333, Specific Conductivity
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120379
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's \Chemical Constituents\" objective. The California Secondary MCL for specific conductivity is 900 uS/cm."
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 2010-12-10 and 2012-07-26
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104333, Specific Conductivity
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120314
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 56
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 56 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Basin Plan's \Chemical Constituents\" objective. The California Secondary MCL for specific conductivity is 900 uS/cm."
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 2012-08-21 and 2017-04-13
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
104331
Region 1     
Mad River HU, Duke Creek
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant.
None of the samples exceed the objective for the COLD beneficial use(s).

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. Eleven of one hundred and twenty samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 104331, pH
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120313
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for pH.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 6.5 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 2010-12-10 and 2012-07-26
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104331, pH
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120604
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 57
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 5 of 57 samples exceeded the water quality standard for pH.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 6.5 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-3)
Temporal Representation: The samples were collected between the dates of 2012-08-21 and 2017-04-13
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104331, pH
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120461
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 57
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 6 of 57 samples exceeded the water quality standard for pH.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 6.5 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 2012-08-21 and 2017-04-13
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 104331, pH
Region 1     
Mad River HU, Duke Creek
 
LOE ID: 120462
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed STORET data for Mad River HU, Duke Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for pH.
Data Reference: Water quality data for tribal lands submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 6.5 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) for the North Coast Region
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (TRINIDADRANCHERIAEPA-MH-2)
Temporal Representation: The samples were collected between the dates of 2010-12-10 and 2012-07-26
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.