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The unlined conveyance channel will be essentially as shown in the FES (1979) except that the a1inement has been moved one-half mile to the east of the original a1inement through the Alamosa NWR. The channel will be fenced to prevent livestock entering the channel. As designed, the conveyance channel will cross 3.1 miles of the Alamosa NWR, intersecting the existing Chicago and Mum ditches, two smaller lateral canals, and one road. The ditches and canals will pass under the conveyance channel in siphon structures, and the channel will siphon under an existing road. The conveyance channel realinement will not have any additional impacts. The channel will not be modified to improve fish habitat; however, it may be stocked by the Colorado Division of Wildlife (CDW) as a put-grow-and-take fishery. A maximum of 10 fishing, access points will be provided. The conveyance channel outlet works will discharge into the Rio Grande at a point downstream from the New Ditch diversion dam. Excavation will be about 4 feet in depth and will require the removal of about 1,500 cubic yards of material. Excavated materials will be used to construct the conveyance channel embankment. About 1,000 cubic yards of riprap will be used to protect the outlet works embankment and the Rio Grande. The FWS is investigating the feasibility of establishing artificial nesting platforms for raptors along the conveyance channel as an enhancement feature. No nesting platforms were included in the 1979 FES. I Public Service Company of Colorado and the San Luis Valley Rural Electric Cooperative, Inc. will provide the transmission facilities to deliver electric power to the project area. The estimated 13 million kilowatt-hours of electri- city a year required for the project will be obtained from electric companies in the San Luis Valley. The 1979 FES estimated that overhead lines would total 44 miles and underground lines would total 96 miles. It is now believed that overhead lines will total more than 44 miles and underground lines will total less than 96 miles with the revised plan. The main line will not be buried. No appreciable change in impacts over those shown in the 1979 FES are anticipated. 1 I I A monitoring system has been established in Stage 1-2 to provide positive identification of any fluctuation in the water table outside the project boundary. Expansion of the system will continue with respect to any remaining stages to be developed. At the time the 1979 FES was prepared, there were 118 observation wells being monitored; there are now more than 300. Production well pumping rates can be adjusted so that the hydrologic balance of the ground waters, within and outside the project area, will not be adversely affected. I I Periodic readings will be taken at 1- to 3-month intervals on more than 300 observation wells in and around the project by the U.S. Geological Survey (USGS), Rio Grande Water Conservancy District (RGWCD), and the Bureau. In Stage 1-2, about 37 of these wells are permanent observation wells. These readings will be taken for positive identification of the water table in and 1 I I d r .....,.. ;~ t'. , . ,l" J ,.1 -,_, "'.. I I