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Notes:
To evaluate direct toxicity to fish, phytoplankton and invertebrates, we used the results of the water quality modeling that Terry has discussed, as well as site specific toxicity testing. And to evaluate potential risks to upper trophic level receptors, we selected the Double-Crested Cormorant to represent fish-eating birds and the Pacific Harbor Seal to represent marine mammals. We then developed a food web model that predicts the fate and transport of contaminants through the food chain. So we used this model to estimate concentrations that would occur in fish and then, assuming that the seals and birds would be feeding on the fish, we estimated an average daily dose of each constituent. We then compared this estimated dose to a threshold level, above which effects might be expected. The types of effects that we considered were generally chronic sub-lethal effects, such as decreased reproduction or development.