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sedimentation processes must be incorporated in the analysis, instead of assuming passive 

 admixtures move with the fluid. 



• Since the Work Plan relies heavily on model results for completing their impact 

 assessment, the Work Plan must await the availability of the model output prior to its issuance. 



• An ecosystem model probably is not appropriate as a predictive tool at this time, due to 

 the lack of verification data for such a model on a bay-wide scale. However, an ecosystem model 

 would be a useful tool for diagnostic examination of the effects of the outfall on the ecosystem. In 

 addition, some process-oriented models focused on low order modes of the biological system 

 would add to the orderliness of the examination of biological impacts. 



• The ranking methodology proposed by the Work Plan is inadequate for biological impact 

 assessment, but adequate for the ESTM. 



• The time and space scales of pertinent impacts have not been defined well in the Work 

 Plan. The time scales should include those small enough to include phytoplankton blooming, and 

 long enough to consider the likely bfetime of the outfall usage (100 years is a good planning 

 horizon). Space scales for the hypotheses likewise have not been identified. Is a mixing zone 

 considered (if so, what is its spatial extent)? 



• A population viability analysis (including population, genetics, and demographics) for 

 the affected endangered species would provide a useful adjunct to the ESTM and biological impact 

 assessment 



• The scope of the consultation wdth experts should expand beyond phone calls, questions 

 about published literature, and review of the ESTM or biological assessment The consultation 

 wdth experts should include substantive discussions and exchange of ideas. 



• The Work Plan should include a discussion and motivation for the selection of the worst 

 case scenario for biological impacts. The implicit assumption is that the worst case is an increase 

 of nutrient concentration within the bay, whereas in fact the worst case might be a decrease of 

 nutrients in the bay. Discussion of this issue is essential. 



SUMMARY: The SAP has identified a host of issues that a proper ESTM and biological 

 assessment should consider. We encourage A. D. Littie and EPA to include discussion of these 

 pertinent aspects in their documentation, to provide full and complete analysis of impacts for the 

 Endangered Species Consultation. The SAP recommends full consideration of the above 

 comments, as well as those contained in the addenda, in the Work Plan. 



Several recommendations came from our discussions: 



• EPA should host a 2-3 day intensive scientific workshop between modelers (ecosystem, 

 hydrodynamic and water quality) and biologists, chemists, geologists, and biogeochemists, to 

 assure iiai the propwr questions arc being asked of the models, and that the models are used to the 

 maximum extent possible, given inherent limitations, to guide the biological impact assessment 



• Analog case studies should be included in the Work Plan to examine the impact of 

 chronic, low level pollution (nutrients, heavy metals) on large ecosystems such as the Seto Inland 

 Sea, Baltic Sea, Adriatic Sea, and Black Sea (for instance), to examine parallels to Massachusetts 

 Bay. Such case studies would provide valuable contrasts and comparisons as an alternative to the 

 imprecision of existing process level models and data in Massachusetts Bay. 



