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Prcdicnng species shifts in the phytoplankton, whether natural or man-made is presently not 

 possible to any reasonable degree of accuracy. Predicting the effects of such changes on 

 zooplankton populations is also not possible. As stated, by being so general, the hypotheses arc 

 largely meaningless. 



The time-space scales over which the hypotheses apply are not clearly stated. For example, the 

 hypotheses refer to effects of the outfall on biota in the area "outside the mixing zone" but the 

 boundaries of this zone and the area outside it are not defined. The time scales to be examined 

 are not given. 



The first hypothesis regarding nutrients appears flawed. The lack of a concentration change in 

 inorganic nitrogen, for example, does not necessarily imply that nitrogen is not being 

 incorporated into particulate matter in the water column. Thus the second hypothesis does not 

 follow from the first, i.e., that a change in nutrient concentration is required for a change in 

 phytoplankton. There could be a large change in phytoplankton with little or no change in 

 nutrients. 



Adequacy of the Proposed Impact Assessment and Ability to Eliminate Ambiguous Findings 



As general as the hypotheses are, the proposed methods for testing them are equally vague. They 

 are presented in a single paragraph after the hypotheses and are followed by a disclaimer stating 

 essentially that, if the hypotheses cannot be answered, then there will be a discussion of the "lines 

 of evidence suggesting the corresponding concerns", whatever that means. No statistical design 

 for testing the hypotheses is specified. 



The proposal relies almost exclusively on the scientific literature for estimating 

 "sensitivities/susceptibilities of the target species to nutrient loading and related ecological 

 changes". Target species are not defined. Does that mean just the endangered species or all the 

 dominant species in the food chain listed in the hypotheses? It is unlikely that the literature will 

 provide even a fraction of the answers required to estimate "apparent threshold effect 

 concentrations", whatever that means (not defined either). 



The use of the USGS hydrodynamic model for snidying the physical circulation of the Bays is 

 a wise choice. This model is state-of-the-an and should give the best estimates of circulation 

 possible at present. The model does not include any biology, however, and therefore the 

 dynamics of nutrient (or toxin) utilization is suspect. Using a simple exponential decay rate for 

 nutrient (or toxin) loss is not meaningful. The distributions of passive tracers generated by the 

 model will provide insights into the "worst case scenario" for nutrient transport. Without 

 modeling the biology (nutrient-plankton dynamics) together with the physics, the estimates of 

 nutrient (or toxin) dispersal will be of littie value. 



In general it is not specified how the USGS model will be used. What areas of the Bays will 

 be examined? What will the physical forcing be exactiy? For example, what wind patterns and 

 intensities will be used? Will the effects of translating storms be examined? What is the grid 

 spacing of the model and over what range of time-space scales is it valid? What external flow 



