Draft Environmental Assesment and Finding of No Significant Impact Gunnision River Activities February 1995

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upstream into the Gunnison River. The passageway site will be fenced with a 6 -foot -high fence for facility and public safety; a bridge over the passageway will permit vehicle access to the right side of the Redlands Diversion Dam and the city of Grand Junction's pumping plant. The overall concept and design of the fish passageway was developed through a series of studies, reviews and meetings conducted cooperatively among the Fish and Wildlife Service, Redlands Water and Power Company, Reclamation, the Recovery Implementation Program, the city of Grand Junction, environmental organizations, and the states of Colorado, Utah, and Wyoming. A more detailed description of the fish passage is contained in Attachment A. Fish Passageway Construction The proposed passageway will be constructed on land owned by the Redlands Water and Power Company. Property interests (such as an easement or exchange) will be acquired by the United States. The city of Grand Junction also has a lease on the land for their pumping facilities. The passageway will be built under a contract administered by Reclamation; funding will be provided by Reclamation through the Recovery Program. The construction area is comprised of river alluvium overlain at some locations by 2 to 10 feet of man- placed fill material. The fill was apparently obtained from the immediate area and consists primarily of lean clay with sand, silty lean clay with sand, and silty sand with some gravel at the surface. Along the alignment of the fish passage, the alluvium consists of up to 9.5 feet of fine- grained material overlying an unknown thickness of coarse gravel and cobbles. The coarse gravel and cobbles lie on bedrock (Morrison Formation) at an unknown depth. The groundwater table in the area is quite shallow and appears to be directly controlled by the river - water elevation. Standard construction practices will be used. Excavators and similar construction equipment will be needed to perform required earthwork. Sheetpiling or cofferdams and dewatering will be required for work in some excavations and in the river channel. A Section 404 permit under the Clean Water Act is required. If dewatering results in a discharge into the Gunnison River, a Section 402 permit will also be needed. Commercial concrete and sand and gravel fill will be used. Construction activities will require 10 to 25 workers. Construction is scheduled to begin in the summer of 1995 and be completed by April 1996. Fish Passageway OQeration The passageway will be operated by the Service on a daily basis, and Reclamation will be responsible for maintenance. Redlands Water and Power will continue to operate the Redlands Diversion Dam in accordance with Colorado water law and their FERC order granting exemption from licensing of a small hydroelectric project (Project No. 6964). Redlands Water and Power will not be responsible for any costs associated with the passageway. Normal 7