Conduct studies to establish and verify significance of copper and/or nickel to selected species.
FY2000/01 1/8 PY
(Note: PYs listed in this Workplan are for Regional Board staff only and reflect anticipated resources needed to work with the TWG and to complete necessary actions by the Regional Board to implement TMDL products.)
Copper and Nickel Bioavailability
Once a policy decision has been made regarding the most appropriate indicator organisms for the South Bay, information can be developed to derive protective site specific objectives that account for the different biological availabilities of copper and nickel forms. The chemical forms that cause toxic effects may be difficult to measure directly. An alternative is to modify dissolved measurements to account for binding (complexation) by organic ligands and other interactions. For example, US EPA has directly linked organic complexation of copper to reduced toxicity though a water effect ratio (WER) in its regulatory guidance.
The City of San Jose has done studies on WER for copper and acute to chronic ratios for nickel. These need to be reviewed in light of the indicator species selection. Additional studies may be needed.