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b. Water Circulation, -Fluctuation, and Salinitv Determinations: During the project operation, minor short-term changes in water clarity, dissolved gases, and nutricnt levels may occur as a result of disturbance to the bottom sediments. No eutrophication of the waters at the project site would be expected. No significant, long-term changes in salinity, water chemistry, color, odor, or taste would be expected to occur. No significant adverse changes in current patterns, flow, stratification, water velocities, or the hydrologic regime would be expected. No specific actions would be required to minimize impacts. Riprap bank protection would extend into the river channel, but is not expected to exceed 3% encroachment into the floodplain and therefore would not have significant adverse effect on flood flow capacity. c. Susnended Particulate/Turbidity Determinations: No significant adverse effect. Project operations would cause temporary turbidity from excavation and fill placement due to disturbance of the lake bottom. Turbidity effects would dissipate over time and distance from the work area and would not have significant long-term effects. Turbidity generating work would be timed to avoid the important fish spawning periods. The completed riverbank protection project would reduce turbidity and sedimentation by eliminating erosion at.the three sites. d. Contaminant Determinations: No significant adverse water quality effects are expected. Only clean fill would be used in the bank protection. e. Aquatic Ecosystem and Organism Determinations: No significant adverse effects. Construction would disrupt existing habitat at the site. Fish would avoid the area because of the noise and activity. Bottom -dwelling organisms within the immediate construction and fill area would be destroyed, but these sites would be re -colonized after project completion. The completed riprap riverbank protection would provide aquatic habitat for fish and aquatic invertebrates. Fish may use the area for feeding, shelter, and possibly spawning. No impacts would be expected to occur on special aquatic sites such as sanctuaries, refuges; wetlands, mud flats, vegetated shallows, or riffle and pool complexes, as none are known to exist in the vicinity of the bank protection sites. f. Federallv Listed Species: According to the U.S. Fish and Wildlife Service all three sites are within the range of the Indiana bat (Myotic sodalis), which is Federally listed as endangered, and the bald eagle (Haliaeetus leucoco hp alus), which is Federally listed as threatened, but that habitat for these species is not present at any of the bank protection sites. Therefore, the riverbank protection projects are not likely to impact any Federally listed species. g. Pronosed Disposal Site Determination: Turbidity would be generated from excavation and placement of the riverbank protection stone. The mixing zone would include the immediate bank protection sites and areas immediat-ly downstream. No i-nifri:ant imfoactc on municipal or private water supplies, recreational or commercial fisheries, water -related recreation, aesthetics, parks, national and historic monuments, cultural or historic sites, research C-3