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humpback or fin whales on occasion. However, this is also not likely to cause 

 significant impact at the population level. The only known previous event of this 

 nature, the death of 14 humpbacks in 1987 attributed to eating mackerel with high 

 saxitoxin loads, represented less than 0.3% of the entire western North Atlantic 

 humpback population, and only 2-3% of the Gulf of Maine regional feeding stock. 



Because of the remaining data gaps and uncertainties in the ecosystem linkages in 

 the Bays system, I would recommend that the National Marine Fisheries Service 

 include the following conditions in their Biological Opinion issued for this Section 7 

 consultation relative to the proposed outfall: 



(i) Further development and validation of the hydrographic and water quality 

 models for the Bays should continue. Models should incorporate water 

 column stratification, as well as biological processes (nutrient uptake, denitri- 

 fication, etc.). Continued agreement of current observed conditions with 

 model predictions for the present outfall location would lend much more be- 

 lievability to any predictions for the new outfall. 



(ii) The site of the proposed outfall, and the surrounding area, should be surveyed 

 regularly for the presence of endangered species. The Biological Assessment 

 relies heavily on the fact that endangered species are rarely observed in that 

 area. However, sighting frequencies are strongly effort-dependent (i.e. "the 

 more you look, the more you are likely to see", and vice-versa), and it is not 

 clear what the level of sighting effort in the outfall vicinity has been relative to 

 other locations (e.g. Stellwagen Bank, eastern Cape Cod Bay). 



(iii) Completion of the entire set of secondary treatment facilities should be explic- 

 itly required, with no possibility of stopping part-way because conditions at 

 that point seem to look "good enough." 



(iv) An effective monitoring program should be established to track nutrients, 

 phytoplankton abundance and species patterns, zooplankton abundance and 

 species patterns, red tides, benthic conditions, contaminant concentrations, 

 etc., with contingency plans for action to be taken in the event of any poten- 

 tial adverse conditions not predicted by the modeling effort. 



(v) Every effort should be required to further reduce effluent concentrations of 

 toxic substances, particularly those such as PCB's with known or suspected 

 effects on higher vertebrates (e.g. immunosuppression, carcinogenicity). 



