# Draft 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Gold Run (Nevada County)
Water Body ID: | CAR5172001220081113234051
Water Body Type: | River & Stream

DECISION ID | 12929
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
Weight of Evidence: | 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. One lines of evidence are available in the administrative record to assess this pollutant. Four 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. Four of 6 samples exceed the USEPA (CTR) mercury-based numeric criterion for human health and this exceeds 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.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 12929

LOE ID: | 25509
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 6
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | A total of 10 water samples were collected at one location from this reach representing six 30-day average samples. Four out of the six 30-day average samples exceeded the USEPA (CTR) mercury-based numeric criterion for human health. The total recoverable mercury concentrations in water ranged from 31.3 ng/l to 631 ng/l with an average of 193 ng/l for the six 30-day average samples.
Data Reference: | Deer Creek Watershed Mercury Survey, draft 2-28-2007
Water Quality Objective/Criterion: | The USEPA (CTR) numeric criterion for the protection of human health for the consumption of both water and fish that live in the water is 50 ng/l (30-day average) for total recoverable mercury (40 CFR 131.38).
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at one location from Gold Run above its confluence with Deer Creek via the trail on the freeway easement.
Temporal Representation: | Water samples were collected during ten sampling events from 15 September 2005 to 29 June 2006.
Environmental Conditions: | Samples represented a range of flow conditions, including two low-flow irrigation season events, four high-flow storms, and four intermediate-flow winter and spring events. Significant gold mining activity occurred during the Gold Rush era within the Gold Run Creek watershed (USGS, 2005).
QAPP Information: | Data quality: Excellent. Protocols for the water sampling conducted for this study are described in Field Sampling Protocols for Total Mercury Water Samples (Friends of Deer Creek, 2005). Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the Citizen Water Monitoring Quality Assurance Project Plan For The Yuba Watershed Monitoring Committee (van der Veen, 2004). The Friends of Deer Creeks mercury survey was a collaboration with the Regional Water Quality Control Board/Central Valley Region and their CALFED mercury QA program.
QAPP Information Reference(s):