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" l' . Pg. 174, C. 1, P. 2. Lead is implicated as a possible problem in Lake Powell. Are data adequate to support this suggestion? Are you suggesting lead may be a problem downstream? Pg. 185, C. 1, P. 1. According to Jack Schmidt: "It would be naive to institutionalize on annual set of flows for beach building because we are nowhere near being able to know what a certain flow will do" - "we need a flow of high enough and long enough to deposit sand in eddies but since these flows also move sediment downstream, we must be careful about what we pick as the ideal beach building flow". The DEIS should explain the gross uncertainty associated with high flow release experiments. Pg. 186, C. 2, P. 1. Beach sand - wind, storm runoff and human activity erode sand from beaches. Boating and waves erode beach faces. These factors take sand from beaches and move it into the river, independent of river flows, and will continue regardless of changes in release patterns. The DEIS should expand the discussion of all erosion sources. ;' '0:;: Pg. 200, C. 1, P. 3. Carothers/Taulbert say, historically, lush growths of algae occurred in the fluctuating zone despite periodic drying. This contrasts with Angradi's results which say 4-6 hours exposure kills it. Algae grew above the reliable wetted stage, probably sustained by back storage, pockets of water among rocks, etc., yet DEIS says the aquatic food base is only indicated by reliable river stage. The DEIS needs to explain the disparity. Pg. 200, C. 1, P. 2. This may grossly bias the comparison, since some food base exists above the minimum reliable stage with fluctuating flows but does not with steady flows. This approach gives no value for accumulation of food base above reliable stage even though some occurs. (See pg. 106, Fig. 111-26; also see Fig. IV-12 which does not recognize the accumulation above reliable stage. ) },~: .,". ;, ".. Pg. 200, C. 2, P. 3. The dam I s coldwater releases are likely responsible for stunting populations of warmwater non-native fish which prey upon or compete with native fish. Without this stunting, historic trends suggest the native fish would likely be in worse shape today. All efforts to provide better habitat for young native fish would be for naught if predatory and competing non-native fish are able to take better advantage of the improved habitat. .'....: "'." :;~~ /~. Pg. 201, C. 1, P. 2. Comments on this page are repeated elsewhere in the text; however, where are the data which documents the decline in native fish populations under normal operations or that they would decline under the alternatives? The text should reference support for this conclusion as no pre-dam surveys of population numbers are available for comparison. 30