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design alternative will result in bank protection that is much more comprehensive than that which currently exists at the site. Most important, the stone toe blocks will more effectively resist undermining of the slope protection than does the surficial stone currently at the site. 4.8 The FWS strongly recommends a project be developed that fits the river dynamics and also saves as many riverbank trees as possible and that trees unavoidably lost be replaced. They note the trees help reduce erosion, provide habitat and shelter for fish and other aquatic organisms, and are valuable for aesthetics and reduction of air pollution and summer heat. Also for the North Shore Drive site, the FWS suggest that, instead of the steel sheet pile or riprap, lunker boxes and/or A jacks may be used at the base of the eroding slope to provide additional fish and wildlife habitat. 4.9 As noted above, the alternative for North Shore Drive was revised to eliminate removal of larger trees along the upper riverbank. Lower riverbank trees that would be removed from the riprap zone are subject to erosive forces and, without the bank protection project, eventually would be undermined and lost. Project authorization does not include funding for added features beyond that necessary for basic. flood protection. Lunker boxes or A jacks could be provided only at the expense of a non -Federal volunteer. 4.10 At the CSO site, FWS's main concern is the method for placing riprap, noting that land- based construction likely would require clearing the bank vegetation, which would open up the site to erosion; whereas equipment use in the river would disturb the bottom and increase turbidity. They suggest that construction equipment could work off of the sandy deposit (delta) in the river adjacent to the outfall. Additional information was requested for review as the project planning progresses. 4.11 The plans and specifications for the project have been written to ensure minimal disruption to the environment during construction. Construction may require access from the riverbank and/or the river depending on the individual construction contractor and available equipment. In water equipment operation would keep to areas of exposed sediments as much as practicable to minimize turbidity and other impacts on aquatic habitat. The contract specifications, however, will require minimization of the in -water area affected. Some riverbank vegetation would be cleared, but only two larger trees (6 -inch or greater diameter) would be removed from the CSO site. All exposed soils on the riverbank would be protected from erosion until turf or other permanent erosion control is established. Over time natural vegetation would fill in the open areas of the riverbank. 4.12 Finally, the FWS noted that the project area is within the range of the Indiana bat (My tis sodalis), which is Federally listed as endangered, and the bald eagle (Haliaeetus leucoconhalus), which is Federally listed as threatened, but that there is no suitable habitat for either of these species within the project areas. 4.13 The Indiana Department of Natural Resources (IDNR). Division of Fish and Wildlife: The IDNR provided stated that formal approval from their agency will be required for EDIE