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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Mokelumne River, North Fork
Water Body ID: CAR5326001420041208150818
Water Body Type: River & Stream
 
DECISION ID
126971
Region 5     
Mokelumne River, North Fork
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on the CWA section 303(d) List under section 3.3 of the Listing Policy, as applicable, using the E. Coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem.

Five lines of evidence are available based on the new E. coli objective. There are an insufficient number of samples available to apply the binomial distribution table in section 3.2 of the Listing Policy to determine beneficial use support.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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. There are insufficient samples available to determine listing status using the newly adopted E. coli objective.
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 126971, Indicator Bacteria
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67850
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of 3 sample results exceed the evaluation guideline value for Escherichia coli.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The U.S. EPA recommended objective for a single-sample maximum allowable density of E. coli in freshwater designated-beach areas is 235 MPN/100mL.
Guideline Reference: 40 CFR Part 131 Water Quality Standards for Coastal and Great Lakes Recreation Waters; Final Rule [Federal Register / Vol. 69, No. 220]
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/27/2008-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 126971, Indicator Bacteria
Region 5     
Mokelumne River, North Fork
 
LOE ID: 23176
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 18 samples from March 2002 to December 2002. Zero out of 18 samples exceeded the evaluation objective.
Data Reference: Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at Mokelumne River, North Fork.
Temporal Representation: Sampling occurred from March 2002 to December 2002.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 126971, Indicator Bacteria
Region 5     
Mokelumne River, North Fork
 
LOE ID: 194678
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Mokelumne River, North Fork to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 532AMA001
Temporal Representation: The samples were collected between the days of 2013-05-29 and 2014-09-23 .
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
122571
Region 5     
Mokelumne River, North Fork
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Seven lines of evidence are available to assess for Cold Freshwater Habitat (COLD). Three lines of evidence are available to assess for Fish Spawning (SPWN). One of the 151 samples exceed the objective for COLD. Zero of the 35 samples exceed the objective for SPWN.

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 the 151 samples exceed the objective for COLD. Zero of the 35 samples exceed the objective for SPWN. 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 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2702
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 21 samples at this location had a DO concentration below 7.0 mg/L.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved Oxygen (DO) concentrations shall not be reduced below 7.0 mg/L (for waters designated as COLD). From the Central Valley Regional Water Quality Control Boards Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Electra Diversion Dam (NFMR5*).

Rationale: Defines water quality in the NFMR at the head of the reach between Electra Diversion Dam and Electra Powerhouse, and is representative of water quality in the reach between Tiger Creek Afterbay Dam and Electra Diversion Dam.
Temporal Representation:
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67656
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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: 0 of 3 samples exceed the water quality objective.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region (CVRWQCB 2007): The dissolved oxygen concentrations shall not be reduced below the following minimum level at any time: Waters designated COLD 7.0 mg/l
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the 532AMA001 (N. Fork Mokelumne River @ Hwy 26).
Temporal Representation: Samples were collected on 8/30/2007, 9/2/2007, 9/5/2007.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 208384
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 34
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 34 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-08-31 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67852
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that the single resultant value does not exceed the criterion for Oxygen, Dissolved.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected on three dates within a one-week period over the time period 8/30/2007-9/5/2007. Therefore, the single sample results were combined (averaged) and represented by a single resultant value.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
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)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67851
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Fish Spawning
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that the single resultant value does not exceed the criterion for Oxygen, Dissolved.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected on three dates within a one-week period over the time period 8/30/2007-9/5/2007. Therefore, the single sample results were combined (averaged) and represented by a single resultant value.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
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)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 208863
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 34
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 34 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-08-31 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2700
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 21 samples at this location had a DO concentration below 7.0 mg/L.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved Oxygen (DO) concentrations shall not be reduced below 7.0 mg/L (for waters designated as COLD)-From the Central Valley Regional Water Quality Control Boards Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Salt Springs Reservoir Dam (NFMR2*).

Rationale: Defines water quality in the NFMR at the head of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay.
Temporal Representation: Samples taken between 7/26/2000 and 9/10/2003 (none more than 2 months apart).
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6273
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 0 of the 25 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Dissolved Oxygen.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Basin Plan Objective sets the minimum Dissolved Oxygen content at 7 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation:
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2703
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 24 samples at this location had a DO concentration below 7.0 mg/L.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved Oxygen (DO) concentrations shall not be reduced below 7.0 mg/L (for waters designated as COLD)-From the Central Valley Regional Water Quality Control Boards Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: Mokelumne River above Electra Powerhouse (MR1*).

Rationale: Defines water quality in the Mokelumne River at the end of the reach between Electra Diversion Dam and Electra Powerhouse.
Temporal Representation: Sample taken between 7/26/2000 and 9/11/2003.
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122571, Oxygen, Dissolved
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2701
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One out of 22 samples at this location had a DO concentration below 7.0 mg/L.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved Oxygen (DO) concentrations shall not be reduced below 7.0 mg/L (for waters designated as COLD)-From the Central Valley Regional Water Quality Control Boards Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR above Tiger Creek Afterbay at Licensee gage M-38 (NMFR3*).

Rationale: Defines water quality in the NFMR at the end of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay
Temporal Representation:
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
 
DECISION ID
129474
Region 5     
Mokelumne River, North Fork
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

3 lines of evidence are available in the administrative record to assess this pollutant. 0 of the 63 samples, reported as a total concentration or with the fraction not reported, exceeded the water quality objective for MUN.

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

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. 0 of the 63 samples, reported as a total concentration or with the fraction not reported, exceeded the water quality objective for MUN, 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: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 129474, Specific Conductivity
Region 5     
Mokelumne River, North Fork
 
LOE ID: 230013
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 129474, Specific Conductivity
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20836
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 25 samples collected by the Surface Water Ambient Monitoring Program exceeded the "recommended" Secondary MCL of 900 uS/cm for electrical conductivity
Data Reference: San Joaquin River SWAMP Monitoring Data - Northeast Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The secondary MCLs for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The ¿recommended¿ level of 900 uS/cm was used as it is intended to be protective of all drinking water uses
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26
Temporal Representation: The samples were collected between January 9, 2002 and December 23, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 129474, Specific Conductivity
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67849
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of 6 sample results exceed the criterion for electrical conductivity.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/30/2007-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
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)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
122573
Region 5     
Mokelumne River, North Fork
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

5 lines of evidence are available in the administrative record to assess this pollutant. 3 of the 50 samples exceed the OBJECTIVE for COLD. 0 of the 32 samples exceed the OBJECTIVE for Fish Spawning and Fish Migration.

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. 3 of the 50 samples exceed the OBJECTIVE for COLD. 0 of the 32 samples exceed the OBJECTIVE for Fish Spawning and Fish Migration. 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: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122573, Temperature, water
Region 5     
Mokelumne River, North Fork
 
LOE ID: 230596
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122573, Temperature, water
Region 5     
Mokelumne River, North Fork
 
LOE ID: 230598
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122573, Temperature, water
Region 5     
Mokelumne River, North Fork
 
LOE ID: 230597
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122573, Temperature, water
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67660
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that 0 of 6 sample results exceed the evaluation guideline value for Water Temperature.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California (1976)
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/30/2007-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAMP (2002) was used for data before Septemper 1, 2008 and SWAMP QAPP (2008) was thereafter.
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)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122573, Temperature, water
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2713
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 3
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Temperature measurements were taken at 3 monitoring stations (NFMR2, NFMR3, and NFMR5) along the North Fork of the Mokelumne River. For each station there were a total of 4 annual maximum temperature values. There was a value for each sampling year, 2000 to 2003. Based on this data, cumulatively for all 3 stations, there were a total of 12 annual maximum measurements of which 3 were in exceedance of the 21.0 degrees C steelhead criteria (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. - Central Valley Regional Water Quality Control Boards Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: The guideline used was from Sullivan et al. (2000) Published Temperature Thresholds-Peer Reviewed Literature which includes reviewed sub-lethal and acute temperature thresholds from a wide range of studies, incorporating information from laboratory-based research, field observations, and risk assessment approaches. This report calculated the Annual Maximum (instantaneous maximum observed during the summer) upper threshold criterion for steelhead trout as 21.0 degrees C. The risk assessment approach used by Sullivan et al. (2000) suggests that an upper threshold for the Annual Maximum of 21.0 degrees C for steelhead will reduce average growth 10% from optimum.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: The three sampling stations (NFMR2, NFMR3, and NFMR5) were located on the North Fork of the Mokelumne River. Specific locations were below Salt Springs Reservoir Dam, above Tiger Creek Afterbay at Licensee gage M-38, and below Electra Diversion Dam.
Temporal Representation: Temperature measurements were taken during years 2000 to 2003.
Environmental Conditions:
QAPP Information: QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
 
DECISION ID
122572
Region 5     
Mokelumne River, North Fork
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. One of the 151 samples exceeded the OBJECTIVE for COLD. Zero of the 32 samples exceeded the OBJECTIVE for REC-2. One of the 38 samples exceeded the OBJECTIVE for REC-1. One of the 6 samples exceeded the OBJECTIVE for MUN.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of the 151 samples exceeded the OBJECTIVE for COLD. Zero of the 32 samples exceeded the OBJECTIVE for REC-2. One of the 38 samples exceeded the OBJECTIVE for REC-1, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. One of the 6 samples exceeded the OBJECTIVE for MUN. 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 26 samples is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67658
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that one of 6 sample results exceed the criterion for pH.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/30/2007-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67657
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that one of 6 sample results exceed the criterion for pH.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/30/2007-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 67659
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: SWAMP data indicates that one of 6 sample results exceed the criterion for pH.
Data Reference: RWB5 Safe to Swim FY0708 FY0809
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH should not be lower than 6.5 or higher than 8.5. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [ N. Fork Mokelumne River @ Hwy 26 - 532AMA001]
Temporal Representation: Data was collected over the time period 8/30/2007-9/3/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6274
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 0 of the 25 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for pH.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH levels should not be lower than 6.5 or higher than 8.5 (Basin Plan Objective)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from Jan 9 2002 to Dec 23 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2699
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 24 samples at this location had a pH below 6.5.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "pH is not to be depressed below 6.5"- From the Central Valley Regional Water Quality Control Board's Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: Mokelumne River above Electra Powerhouse.

Rationale: Defines water quality in the Mokelumne River at the end of the reach between Electra Diversion Dam and Electra Powerhouse.
Temporal Representation: Samples taken between 7/26/200 and 9/11/2003.
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2697
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 22
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 22 samples at this location had a pH below 6.5.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Companys Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "pH is not to be depressed below 6.5"- From the Central Valley Regional Water Quality Control Board's Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR above Tiger Creek Afterbay at Licensee gage M-38.

Rationale: Defines water quality in the NFMR at the end of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay.
Temporal Representation:
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2698
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 21 samples at this location had a pH below 6.5.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137)[Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "pH is not to be depressed below 6.5"- From the Central Valley Regional Water Quality Control Board's Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Electra Diversion Dam.

Rationale: Defines water quality in the NFMR at the head of the reach between Electra Diversion Dam and Electra Powerhouse, and is representative of water quality in the reach between Tiger Creek Afterbay Dam and Electra Diversion Dam.
Temporal Representation:
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2696
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 21 samples had a pH below 6.5.

Year 2003 and Historical Water Quality Results for In Situ Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A1]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: "pH is not to be depressed below 6.5"- From the Central Valley Regional Water Quality Control Board's Water Quality Control Plan (Basin Plan).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Salt Springs Reservoir Dam.

Rationale: Defines water quality in the NFMR at the head of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay.
Temporal Representation: Samples taken between 7/26/2000 and 9/10/2003 (none more than 2 months apart).
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 228672
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 228568
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 122572, pH
Region 5     
Mokelumne River, North Fork
 
LOE ID: 228670
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 32
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB5 Monitoring data for Mokelumne River, North Fork to determine beneficial use support and results are as follows: 0 of 32 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (532AMA001)
Temporal Representation: The samples were collected between the dates of 2010-09-02 and 2017-10-10
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
72870
Region 5     
Mokelumne River, North Fork
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 2 available concentrations exceeded the USEPA Primary MCL and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. The recommendation is based on staff findings that 0 of 2 available concentrations exceeded the California Toxics Rule and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 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 72870, Arsenic
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6268
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the CTR level of 340 ug/L for dissolved arsenic
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved arsenic levels should not exceed the CTR 1-hour average maximum concentration of 340 ug/L
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26 and at Hwy 27
Temporal Representation: The samples were collected on June 13, 2002 and on June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72870, Arsenic
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20553
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the USEPA Primary MCL of 10 ug/L for total arsenic
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Total arsenic levels must not exceed the USEPA Primary MCL of 10 ug/L
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26
Temporal Representation: The samples were collected on June 13, 2002 and June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
72181
Region 5     
Mokelumne River, North Fork
 
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 listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 2 available concentrations exceeded the California Toxics Rule for Cold Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. The recommendation is also based on staff findings that 0 of 2 available concentrations exceeded the Department of Public Health Primary MCL for Municipal & Domestic Supply and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met."
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72181, Cadmium
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6270
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR criterion for dissolved cadmium
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved cadmium levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average dissolved)=(EXP(1.128*LN(hardness)-3.6867))*(1.136672-(LN(hardness)*0.041838))
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Highway 26
Temporal Representation: The samples were collected on June 13, 2002 and June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72181, Cadmium
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20591
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the California Primary MCL of 5 ug/L for total cadmium
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Total cadmium levels should not exceed the California Department of Public Health Primary MCL of 5 ug/L
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Highway 26
Temporal Representation: The samples were collected on June 13, 2002 and June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
72182
Region 5     
Mokelumne River, North Fork
 
Pollutant: Chromium (total)
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: The decision has not changed. Region 5 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 2 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 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 72182, Chromium (total)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20586
 
Pollutant: Chromium (total)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Chromium.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Chromium levels should not exceed 50 ug/L (Department of Public Health Primary MCL).
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from June 13 2002 to June 26 2002.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
69538
Region 5     
Mokelumne River, North Fork
 
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 section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Two of the 25 samples exceed the CTR criteria for COLD and 0 of the 4 samples exceed the MCL for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the 25 samples exceeded the CTR for COLD and zero of the 4 samples exceeded the MCL for MUN and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list 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 69538, Copper
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20657
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Copper.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Copper levels should not exceed 1300 ug/L (Department of Public Health Primary MCL).
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from June 13, 2002 to June 26, 2002.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 69538, Copper
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20658
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Copper.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Copper levels should not exceed 1300 ug/L (Department of Public Health Primary MCL).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from June 13, 2002 to June 26, 2002.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 69538, Copper
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6272
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Copper.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved Copper levels should not exceed calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.9422*LN(hardness)-1.7))*(0.96) (CTR)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from June 13, 2002 to June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 69538, Copper
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2708
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Two out of 23 samples exceeded the criteria. The measurements were made using two different approaches. One set of samples had a higher quantitation limit of 0.5 ug/L. The other set of samples had a lower quantitation limit of 0.03 ug/L. Only two of the higher quantitation limit level samples could be used for this assessment. These were the two samples that were in exceedance of the criteria.

Historical Water Quality Results for Analytical Laboratory Measurements PG&E Company Mokelumne River Project (FERC 137) [Table A2] (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Hardness based criteria from USEPA (CTR) ranged from 2.65 ug/L to 0.43 ug/L.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations along the north fork, NFMR2, NFMR3, and NFMR5.
Temporal Representation: Samples taken between 3/14/2001 to 12/07/2005.
Environmental Conditions:
QAPP Information: Well documented QA/QC including report on certified analytical reports and Chain-of-Custody documentation.
QAPP Information Reference(s):
 
 
DECISION ID
72018
Region 5     
Mokelumne River, North Fork
 
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 listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 2 available concentrations exceeded the California Toxics Rule for Cold Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. The recommendation is also based on staff findings that 0 of 2 available concentrations exceeded the Department of Public Health Primary MCL for Municipal & Domestic Supply and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 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 72018, Lead
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20635
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the Primary MCL of 15 ug/L for total lead
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Total lead levels should not exceed 15 ug/L (Department of Public Health Primary MCL)
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork, Mokelumne River at Hwy 26
Temporal Representation: The samples were collected on June 13, 2002 and on June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72018, Lead
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6276
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved lead
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved lead levels should not exceed the calculated CTR value based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(1.273*LN(hardness)-1.46))*(1.46203-(LN(hardness)*0.145712))
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork of the Mokelumne River atHwy 26
Temporal Representation: The samples were collected on June 13, 2002 and on June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
72019
Region 5     
Mokelumne River, North Fork
 
Pollutant: Nickel
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 section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of two samples exceed the CTR for COLD and zero of two samples exceed the MCL for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of two samples exceeded the CTR for COLD and zero of two samples exceed the MCL for MUN and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 72019, Nickel
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6284
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR for dissolved nickel
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved nickel levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26 and at Hwy 27
Temporal Representation: The samples were collected on June 13, 2002 and on June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 72019, Nickel
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20693
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Neither of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the Primary MCL of 100 ug/L for total nickel
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Total nickel levels should not exceed 100 ug/L (Department of Public Health Primary MCL)
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26 and at Hwy 27
Temporal Representation: The samples were collected on June 13, 2002 and on June 26, 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
76011
Region 5     
Mokelumne River, North Fork
 
Pollutant: Nitrate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(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 3.1a one line(s) of evidence are necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. One of the nine samples exceeds 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. One of nine samples exceeded 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 76011, Nitrate
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59482
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L. 2 of the 3 were reported as non-detects. These non-detect are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR5 (NFMR in diversion canal at Electra Diversion Dam).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
Line of Evidence (LOE) for Decision ID 76011, Nitrate
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59480
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR2 (NFMR below Salt Springs Reservoir Dam).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
Line of Evidence (LOE) for Decision ID 76011, Nitrate
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59481
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L. 2 of the 3 were reported as non-detects. These non-detect are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR3 (NFMR above Tiger Creek Afterbay at Licensee Gage M-38 d).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
 
DECISION ID
71606
Region 5     
Mokelumne River, North Fork
 
Pollutant: Nitrate as Nitrate (NO3)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 11 samples exceed the MCL for MUN and zero of two samples exceed the MCL for COLD.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 11 samples exceeded the MCL for MUN and zero of two samples exceed the CTR for COLD 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 71606, Nitrate as Nitrate (NO3)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20754
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Nitrate-N.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Nitrate-N levels should not exceed 45 mg/L (Department of Public Health Primary MCL)
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from Jun 13 2002 to Jun 26 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71606, Nitrate as Nitrate (NO3)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59480
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR2 (NFMR below Salt Springs Reservoir Dam).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
Line of Evidence (LOE) for Decision ID 71606, Nitrate as Nitrate (NO3)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59482
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L. 2 of the 3 were reported as non-detects. These non-detect are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR5 (NFMR in diversion canal at Electra Diversion Dam).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
Line of Evidence (LOE) for Decision ID 71606, Nitrate as Nitrate (NO3)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 59481
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: 0 of the 3 samples do not exceed the water quality objective for Nitrate (as N). The Nitrate (as N) MCL objective is 10 mg/L. 2 of the 3 were reported as non-detects. These non-detect are less than or equal to the water quality standard, the value will be considered as meeting the water quality standard, objective, criterion, or evaluation guideline.
Data Reference: Data for Various Projects by Pacific Gas and Electric Company, 2002-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Sacramento and San Joaquin River Region (2007): Waters designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The nitrate (as N) MCL is 10 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at NFMR3 (NFMR above Tiger Creek Afterbay at Licensee Gage M-38 d).
Temporal Representation: Samples were collected from March to Sept 2008.
Environmental Conditions:
QAPP Information: No quality assurance information was provided.
QAPP Information Reference(s): Quality Assurance Program Plan for Projects Requiring Water Quality and/or Water Temperature Monitoring, Version 4.
 
Line of Evidence (LOE) for Decision ID 71606, Nitrate as Nitrate (NO3)
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6285
 
Pollutant: Nitrate as Nitrate (NO3)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 0 of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from Jun 13 2002 to Jun 26 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
71760
Region 5     
Mokelumne River, North Fork
 
Pollutant: Selenium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the one sample exceeds the CTR for COLD and zero of the one sample exceeds the MCL for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of one sample exceeded the CTR for COLD and zero of one sample exceeded the MCL for MUN and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 71760, Selenium
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6942
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 1 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Selenium.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006) Selenium levels should not to exceed 5 ug/L (CTR)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The samples were collected from Oct 24 2002 to Oct 24 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71760, Selenium
Region 5     
Mokelumne River, North Fork
 
LOE ID: 20345
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of the 1 sample was collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Selenium.
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Selenium levels should not exceed 50 ug/L (Department of Public Health Primary MCL)
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Sample was collected at N.Fork Mokelumne River @ Hwy 26.
Temporal Representation: The sample was collected on Oct 24 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
73379
Region 5     
Mokelumne River, North Fork
 
Pollutant: Total Nitrogen as N
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.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of 59 samples exceed the MCLs/Title 22 Table 6444-A Primary for MUN.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 59 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 73379, Total Nitrogen as N
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2709
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 15 samples at this location exceed the standard for Total Nitrate as N.

Historical Water Quality Results for Analytical Laboratory Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A2]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Ten mg/L (MCLs/Title 22 Table 6444-A Primary).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Electra Diversion Dam (NFMR5*).

Rationale: Defines water quality in the NFMR at the head of the reach between Electra Diversion Dam and Electra Powerhouse, and is representative of water quality in the reach between Tiger Creek Afterbay Dam and Electra Diversion Dam.
Temporal Representation: Samples taken between 3/14/2001 and 5/14/2002.
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 73379, Total Nitrogen as N
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2711
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 14 samples at this location exceed the standard for Total Nitrate as N.

Historical Water Quality Results for Analytical Laboratory Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A2]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Ten mg/L (MCLs/Title 22 Table 6444-A Primary).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR below Salt Springs Reservoir Dam (NFMR2*).

Rationale: Defines water quality in the NFMR at the head of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay
Temporal Representation: Samples taken between 3/14/2001 and 5/14/2002 (none more than 2 months apart).
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 73379, Total Nitrogen as N
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2710
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 15 samples at this location exceed the standard for Total Nitrate as N.

Historical Water Quality Results for Analytical Laboratory Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A2]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Ten mg/L (MCLs/Title 22 Table 6444-A Primary).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: Mokelumne River above Electra Powerhouse (MR1*).

Rationale: Defines water quality in the Mokelumne River at the end of the reach between Electra Diversion Dam and Electra Powerhouse.
Temporal Representation: Sample taken between 3/14/2001 and 5/14/2002.
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 73379, Total Nitrogen as N
Region 5     
Mokelumne River, North Fork
 
LOE ID: 2712
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero out of 15 samples at this location exceed the standard for Total Nitrate as N.

Historical Water Quality Results for Analytical Laboratory Measurements PG& E Company Mokelumne River Project (FERC 137) [Table A2]. (PG&E, 2003b).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Ten mg/L (MCLs/Title 22 Table 6444-A Primary).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Location: NFMR above Tiger Creek Afterbay at Licensee gage M-38 (NMFR3*).

Rationale: Defines water quality in the NFMR at the end of the reach between Salt Springs Reservoir Dam and Tiger Creek Afterbay.
Temporal Representation: Samples collected between 3/14/2001 and 5/14/2001.
Environmental Conditions:
QAPP Information: Well documented QA/QC including 174 page report on Certified Analytical Reports and Chain-of-Custody Documentation.
QAPP Information Reference(s):
 
 
DECISION ID
74491
Region 5     
Mokelumne River, North Fork
 
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 section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the two samples exceed the CTR for COLD and zero of the two samples exceed the MCL for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of two samples exceeded the CTR for COLD and zero of two samples exceeded the MCL for MUN and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 74491, Zinc
Region 5     
Mokelumne River, North Fork
 
LOE ID: 21363
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the Secondary MCL of 5,000 ug/L for total zinc
Data Reference: San Joaquin River SWAMP Monitoring Data - Northeast Basin
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Total zinc levels should not exceed 5,000 ug/L (Department of Health Services Secondary MCL)
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26 and at Hwy 27
Temporal Representation: The samples were collected on June 13, 2002 and on June 26 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 74491, Zinc
Region 5     
Mokelumne River, North Fork
 
LOE ID: 6290
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the 2 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved zinc
Data Reference: San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved zinc levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the North Fork Mokelumne River at Hwy 26 and at Hwy 27
Temporal Representation: The samples were collected on June 13, 2002 and June 26 2002
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):