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DDJC Tracy INITIAL RELEASE of the lagoon is not available, the lagoon was probably not widely used for recreational fishing. The lagoon was the site of a one-time fishing derby and was stocked with carp, catfish, perch, and bass for very limited recreational fishing activity until 1992, when DDJC Tracy drained the lagoon (Montgomery Watson, 1996b;DDJC Tracy, 1997a). Although recreational use of the lagoon was limited, ATSDR evaluated the potential of indirect exposure to site-related contaminants that could occur through the consumption of fish caught from the on-site stormwater lagoon. No fish sampling had been conducted, however, prior to emptying the lagoon of fish. To characterize the potential contamination in the lagoon fish, ATSDR evaluated the results of sediment samples(18) collected from the lagoon during its RI activities. The samples were analyzed for SVOCs, metals, pesticides, and polychlorinated biphenyls (PCBs). With the exception of polycyclic aromatic hydrocarbons (PAHs) and dieldrin concentrations, which slightly exceeded ATSDR's CREGs, contaminant concentrations were below ATSDR comparison values for soil. Because even low levels of contaminants could accumulated in fish, ATSDR evaluated the lagoon sediment data along with bioaccumulation parameters (e.g., translocation factors) to estimate contaminant concentrations in lagoon fish. Using the estimated fish tissue concentration, ATSDR estimated exposure doses to determine potential health hazards from eating the lagoon fish. Appendix C describes the method and assumptions used by ATSDR to estimate exposure doses and cancer risk. ATSDR believes that the assumptions used to predict contaminant concentrations in fish and estimate exposure doses are very conservative and, therefore, greatly overestimate the level of actual exposure for anyone eating fish from the lagoon. The estimated exposure doses and cancer risk estimates are provided in Appendix C, Table C4. As the table indicates, the conservatively derived exposure doses are lower than corresponding MRLs/RtDs. ATSDR therefore believes that consumption of fish in the past poses no noncancer health concerns. ATSDR also estimated cancer risk for consumption of fish from the stormwater lagoon assuming a 30-year exposure period. The resulting excess cancer risk estimates are below levels likely to contribute to excess cancer in the population. No public health hazards occurred from consumption of lagoon fish in the past. Contaminants most likely did not accumulate in fish, if arty, to levels associated with adverse human health effects. 17