Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Wildwood, Lake (Nevada County)
Water Body ID: CAL5172002020080810191901
Water Body Type: Lake & Reservoir
 
DECISION ID
13318
Region 5     
Wildwood, Lake (Nevada County)
 
Pollutant: Mercury
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Resource Extraction
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.5 of the Listing Policy. Under section 3.5 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. Fourteen of the samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of 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. The guideline used satisfies the requirements of section 6.1.3 of the Policy.
4. Fourteen of 14 samples exceed the USEPA fish tissue criterion for human health and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
5. 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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 13318, Mercury
Region 5     
Wildwood, Lake (Nevada County)
 
LOE ID: 26445
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 11
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Eleven Largemouth Bass samples were collected for tissue analysis at one location from this reach. All 11 samples exceeded the USEPA fish tissue criterion for human health. The wet weight mercury concentrations of the 11 samples ranged from 0.54 ppm to 1.17 ppm, with an average of 0.75 ppm. All of the samples were collected from fish with total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: Deer Creek Watershed Mercury Survey. Draft Report. Friends of Deer Creek.
 
SWAMP Data: Non-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
 
Evaluation Guideline: The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day.
Guideline Reference: Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
 
Spatial Representation: Samples were collected at one location near the center of Lake Wildwood.
Temporal Representation: Fish samples were collected during July 2008.
Environmental Conditions: Significant gold mining activity occurred during the Gold Rush era within the Lake Wildwood watershed and the lands inundated by Lake Wildwood (USGS, 2005).
QAPP Information: Data quality: Good. Quality Control for the fish sampling portion of this study was conducted as described in the Deer Creek Watershed Mercury Survey, which was the same sample collection procedure as USGS (Finkler et al., 2008; May et al., 2000). The fish tissue samples were analyzed by the Texas A&M University Laboratory.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 13318, Mercury
Region 5     
Wildwood, Lake (Nevada County)
 
LOE ID: 22602
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fish were sampled for tissue analysis at one location from Lake Wildwood. A total of 3 out of 3 samples exceeded the USEPA fish tissue criterion for human health. The average wet weight mercury concentration in fish tissue was 0.41 ppm for all 3 composite samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedances are, by species: Carp- one 6-fish composite sample, 0.47 ppm, 1 exceedance; Largemouth Bass- 2 composite samples, 0.36 and 0.41 ppm, 2 exceedances. All 3 composite samples were collected from fish with average total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: Toxic Substances Monitoring Program: Freshwater Bioaccumulation Monitoring: TSM Program Data 1978-2000. State Water Resources Control Board, Division of Water Quality
 
SWAMP Data: Non-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
 
Evaluation Guideline: The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day.
Guideline Reference: Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
 
Spatial Representation: Samples were collected at one location near the center of Lake Wildwood.
Temporal Representation: Fish samples were collected during two sampling events on 10/2/1987 and 8/22/1990.
Environmental Conditions: Significant gold mining activity occurred during the Gold Rush era within the Lake Wildwood watershed and the lands inundated by Lake Wildwood (USGS, 2005).
QAPP Information: Data quality: Good. Quality Control for the fish sampling, tissue preparation, mercury analysis, and QA sample analysis portions of this study was conducted as described in the Toxic Substance Monitoring Reports for 1987 and 1990 (Rasmussen and Starrett, 1989; Rasmussen, 1992). Additional Quality Control information for the laboratory analysis portions of the data collected in 1990 is found in the Laboratory Quality Assurance Program Plan prepared by the Department of Fish and Game (DFG, 1990).
QAPP Information Reference(s):