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permit AKY LEVEL OF IMPACT, such that the comparison with the present outfall site is not 

 germane. 



5) The long-term impact of this increased nutrient loading to the Massachusetts Bay system 

 has not been fully addressed. What are the possible impacts to the Bay system from long-term, 

 low-level chronic nutrient loading? Given that the outfall will certainly be in operation for decades, 

 if not a half-century or more, the long-term, chronic input should be addressed at least by analogy 

 to other embayments world-wide experiencing suCh long-term input. 



6) The Assessment does not specifically address the relative impacts of the outfall 

 operations under the planned phasing of Secondary Treatment, versus the scenario of delayed or 

 canceled secondary treatment. Will there be a difference in the environmental degradation if 

 secondary trcamient never comes on line, or if it is delayed by a decade or more? If there are no 

 significant differences, does this finding affect the decision to elect secondary treatment? 



7) The potential effects of pathogens (such as viruses and bacteria) on endangered species 

 have not been discussed. Experience at the San Diego ocean outfall, for instance, indicates that 

 bacterial die-off occurs much more slowly than predicted by models, resulting in violanons of 

 California water quality standards in the nearshore waters. What are the analogous conditions in 

 Massachusetts Bay, and what are the implications for the endangered species? 



8) Whereas the Work Plan focused strongly on the 3-D model results from the USGS and 

 MWRA, the present Assessment states that such model results are not critical for reaching their 

 conclusions. It is not clear why this reversal in opinion has occurred, and why the presently 

 unavailable model results would not enhance the Assessment as originally indicated. Specifically, 

 pages 13 and 14 of the Work Plan show a suite of scenarios that were to be examined using the 3- 

 D model results. Why is analysis of these scenarios no longer necessary to complete the 

 Assessment? 



9) Some earlier comments by the SAP have not been addressed in a comprehensive 

 fashion. We assume these earlier comments (included here as an attachment) will be reviewed by 

 NOAA/NMFS while completing their Biological Opinion, rather than reiterating all the comments 

 here. However, some of the potentially critical issues not addressed in the Assessment are 

 mentioned here briefly: 



i) The potential for geoaccumulation of toxics is not addressed. The Assessment 

 merely states that resuspension will reduce the sediment toxicity by moving the sediment from 

 place-to-place. However, resuspension may accelerate accumulation of toxic sediments in some 

 locations (depocenters), which presently are accumulation sites for fine-grained sediments. Can 

 such depocenters be located based on existing information? What impact might geoaccumulation in 

 specific depocenters have on sand lances or benthophages? 



ii) What are the effects of surface waves on plume and sediment dispersal? The 

 Work Plan stated the 3-D model would use such waves as input parameters. In the absence of 

 such full 3-D model results, can the assessment discuss the role of surface gravity waves in 

 dispersing sediments and water? For instance, the present outfall and dispersal panems are 

 concentrated in shallow water, where wave action is much greater. By contrast, the proposed 

 outfall location is located in what may be more quiescent deeper waters where wave mixing may be 

 less significant. Is this a significant process affecting dispersal of sediments and water? 



iii) The chemical form of tlie nutrients may vary depending on secondary versus 

 primary treatment, ranging possibly from more organic complexes for primary treatment versus 

 more dissolved inorganic (and more readily usable) forms for secondary treacmenL What is the 



