California Code of Regulations
Title 23 - Waters
Division 4 - Regional Water Quality Control Boards
Chapter 1 - Water Quality Control Plans, Policies, and Guidelines
Article 5 - Central Valley Region
Section 3945 - Program for Control of Mercury in Clear Lake
Current through Register 2024 Notice Reg. No. 38, September 20, 2024
Regional Board Resolution No. R5-2002-0297, adopted on December 6, 2002, by the Central Valley Regional Water Quality Control Board, modifies the regulatory provisions of the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins by establishing a program for the control of mercury in Clear Lake. The modifications included:
1. Surface Water Beneficial Uses -- The commercial and sport fishing beneficial use designation was added to Clear Lake.
2. Water Quality Objective for Methylmercury -- A Water Quality Objective expressed as methylmercury concentration in fish tissue was added for Clear Lake. Methylmercury concentrations are not to exceed 0.09 mg/kg in trophic level 3 fish and 0.19 mg/kg in trophic level 4 fish.
3. Implementation Plan to Reduce Mercury -- The implementation plan to reduce mercury levels in lake sediment and fish tissue includes a requirement to reduce mercury loads from the Sulphur Bank Mercury Mine by 95%, reduce lake sediment mercury concentrations by 70%, and reduce mercury loads from tributary creeks by 20%. Implementation of detailed remediation plans is required within ten years.
4. Monitoring Program -- A monitoring and surveillance program includes criteria for determining compliance with the fish tissue objective. The program requires mercury monitoring in water, sediment, and fish tissue and specifies monitoring frequencies.
1. New section summarizing amendments to Basin Plan filed 7-15-2003; Basin Plan amendment adopted by the Central Valley Regional Water Quality Control Board 12-6-2002 per Resolution No. R5-2002-0207 and approved by the State Water Resources Control Board 5-21-2003 per Resolution 2003-0040, approved by OAL and effective per Government Code section 11353 on 7-15-2003 (Register 2003, No. 29).
