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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: American River, North Fork
Water Body ID: CAR5145501020020610125753
Water Body Type: River & Stream
 
DECISION ID
11187
Region 5     
American River, North Fork
 
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: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data are available from one line of evidence for this pollutant.

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 recommendation is based on the staff findings that:
1. A total of 4 out of 4 samples exceeded the USEPA fish tissue criterion for human health. This number of exceedences is greater than the allowable frequency listed in Table 3.1 of the Listing Policy.
2. The guideline used satisfies the requirements of section 6.1.3 of the Policy.
3. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
4. The data used satisfies the data quantity requirements of Section 6.1.5 of the 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 11187, Mercury
Region 5     
American River, North Fork
 
LOE ID: 22957
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fish were sampled for tissue analysis at one location from this reach. A total of 4 out of 4 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 4 samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedances are, by species: Sacramento Sucker- 2 composite samples, 0.42 and 0.48 ppm, 2 exceedances; Smallmouth Bass- 2 composite samples, 0.33 and 0.41 ppm, 2 exceedances. All 4 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 (USEPA, 2001)
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 from the American River, North Fork, approximately 0.5 miles upstream of the confluence with the American River, Middle Fork
Temporal Representation: Fish samples were collected during three sampling events on 10/16/1981, 10/20/1982 and 9/14/1988.
Environmental Conditions: Significant gold mining activity occurred during the Gold Rush era within the American River, North Fork watershed (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 1981, 1982 and 1988-89. (La Karo et al., 1982; La Karo, 1983; Rasmussen and Blethrow, 1991).
QAPP Information Reference(s):