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Goals and Objectives
Evaluate potential ecological effects due to chemicals mobilized during dredging/disposal
- Is there potential for effects due to direct toxicity? (Phytoplankton, aquatic invertebrates, fish)
- Is there potential for effects due to food-chain toxicity? (birds, marine mammals)
- Is there a difference between no project conditions and predicted project conditions?
Notes:
MS. HUNT: So, as Terry discussed, the process of dredging can stir up constituents in the sediment and result in increased concentrations in the water. So the objective of this part of the evaluation was to consider the potential effects to the ecosystem due to increases in concentrations in the water. The questions we asked were, first, is there a potential for direct toxicity to those organisms that live in the water such as fish and vertebrates and phytoplankton. Then is there a potential for food web toxicity to upper trophic level receptors. Certain constituents such as PCB's and mercury can accumulate in the tissue of fish an invertebrates, potentially affecting receptors that are feeding on them such as fish eating birds or marine mammals. And then we also asked, is there a difference in terms of the predicted effects under the No- Project conditions vs. the predicted project conditions.