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1 am most comfortable with the conclusions relative to potential impacts related to 

 nutrient enrichment, somewhat less so with the sections on toxic contaminant 

 impacts, and least so with the conclusions related to impacts from possible in- 

 creases in the frequency of toxic phytoplankton blooms. All of the Assessment's 

 conclusions seem to rely heavily on the results of the current version(s) of the 

 circulation models for the Bays. It appears to me that validation of the existing 

 models thus far shows the models to be good predictors of nutrient loadings from 

 the current outfall. If the modeling predictions for the new outfall are correct, then 

 nutrient loading in the Bays (and in Boston Harbor) outside of the immediate vicini- 

 ty of the outfall will be lower than existing levels, so any potential impacts of the 

 new outfall must similarly be less likely. 



In my opinion, right whales are the onty one of the endangered species included in 

 the Assessment at all likely to suffer significant detrimental impact to their popula- 

 tion from the outfall. Even though the proportion of the population utilizing the 

 Bays system in a given year is less than 20%, and usually substantially smaller 

 than that, it is frequently a critical segment of the population (mothers and calves, 

 juveniles), and the population is so severely depleted that small impacts on a few 

 individuals might have serious effects. Nevertheless, the models predict no detect- 

 able change in nutrients due to the change in outfall location in the eastern half of 

 Cape Cod Bay, which is the primary right whale feeding area. Therefore significant 

 outfall-related changes in zooplankton species or abundance, already highly variable 

 between years with no apparent detrimental effect on the whale population, are 

 not likely. Significant effects of toxic phytoplankton blooms on right whales are 

 probably also not likely, since the seasons of principal right whale occupancy (April) 

 and red tide frequency (summer) are largely non-overlapping. 



The other endangered whale and sea turtle species are much less likely to be signif- 

 icantly impacted by any aspect of the proposed outfall. The proportions of their 

 populations inhabiting the Bays at any given time are small, probably so small that 

 a single catastrophic event, even one which killed most of the individuals in the 

 Bays at the time, would not have a significant impact on population survival, sta- 

 tus, or recovery. The numbers of sea turtles in the Bays at any time is negligible, 

 though this is least clear for the Kemp's ridley. Nutrient loadings so severe as to 

 radically alter the food chain in the Bays to completely different species would 

 simply mimic events in 1986 (and possibly now underway in 1993), when sand 

 lance stocks crashed and humpback and fin whales simply moved elsewhere to 

 feed. Sighting data since the late 1970's, when relatively intensive study of 

 cetaceans off the Northeast coast began, and limited data for prior years, suggest 

 that drastic shifts in cetacean distributions are frequent responses to interannual 

 and longer-term variability in prey stocks (Payne et a/., 1986, 1990; Kenney et al., 

 in prep.). An increased frequency of toxic phytoplankton blooms, which the as- 

 sessment suggests is not likely, could impact a fevv, or even more, individual 



