On November 18, 2015, the San Francisco Bay Regional Water Quality Control Board adopted Resolution No. R2-2015-0048, amending the Water Quality Control Plan for the San Francisco Bay Region to address impairment of the North Bay from selenium. This amendment establishes a total maximum daily load (TMDL) expressed as total annual selenium load to North San Francisco Bay equal to the sum of current loads from external sources and an implementation plan. The amendment establishes two numeric targets:
The main goal of the implementation plan is to maintain existing water quality and prevent increases in selenium loading from petroleum refineries, the largest controllable source of selenium, and from the Central Valley watershed. Therefore the implementation plan establishes load-based effluent limits for petroleum refineries that will be incorporated into NPDES permits, and includes monitoring of ambient waters, and monitoring to ensure attainment of the Central Valley load allocation.
Cal. Code Regs. Tit. 23, § 3919.16