Our general approach will be to evaluate and revise basin plan objectives to reflect national criteria guidances, to evaluate the appropriateness of a site specific objective (SSO) for nickel, and to quantify the speciation and sources of nickel in shallow embayments. National criteria for metals are now expressed as dissolved rather than total recoverable concentrations. Basin Plan objectives need to be updated to reflect these changes in USEPA guidance. The dissolved nickel criteria are exceeded only sporadically at a single location in western San Pablo Bay, and these exceedances may be due to natural nickel sources. If ambient free nickel ion concentrations are determined to be below levels toxic to sensitive species, and nickel inputs to the northern reach are demonstrated to be dominated by natural sources, nickel may be delisted, and a SSO for nickel may be established.