Issues associated with the possible impairment of estuarine beneficial uses by copper and nickel need resolution. These are issues that must be resolved in the consideration of site specific objectives and associated reassessment of the South Bay. Two critical issues pertain to the appropriate indicator species that should be considered and the extent of copper and nickel bioavailability in South San Francisco Bay.
The extent of the water quality impairment due to copper and nickel depends on the indicator species selected. For example, many types of marine algae are orders of magnitude more sensitive to copper than larger invertebrates. Current and proposed Federal criteria are driven by the latter, i.e., reproductive success of the blue mussel, Mytilus edulis. The only algae represented in the national dataset are diatoms, the most copper-tolerant species. Consequently, the significance of copper sensitive algae species, such as dinoflagellates and cyanobacteria, needs to be resolved. An initial review of indicator organisms for South San Francisco Bay has been prepared by the City of San Jose and is currently being reviewed by the Santa Clara Basin Watershed Management Initiative, Regional Board staff, and external scientists.