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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />000857 <br /> <br /> <br />elements into the food chain, Once Ridges Basin Reservoir is filled there is the <br />potential of bioaccumulation of trace elements in fish in reservoir. Reclamation <br />will develop and implement a monitoring program at Ridges Basin Reservoir to <br />determine the extent of bioaccumulation of trace elements in fish within the <br />reservoir, The program will last four consecutive years and be initiated two years <br />after the reservoir is filled. Reservoir water quality variables to be monitored <br />include but not limited to: <br />(a) dissolved oxygen, temperature, pH, conductivity, salinity, etc, <br />(b) nutrients and trace elements in water at various reservoir depths <br />(c) trace elements in sediments <br />(d) trace elements in bald eagle food items <br />(2) Fish tissue will be taken periodically during the four years from various species <br />and analyzed for trace elements to assess the potential for bioaccumulation, <br />Tissues will be taken from fish collected from various locations in the reservoir, <br />but inflow areas may be targeted, depending on suspected sources of trace <br />elements. These analyses will also be compared to standards for human <br />consumption, <br />(3) Reclamation will monitor water leaving Ridges Basin Reservoir through the dam <br />outlet facilities to determine if escapement of nonnative fishes is occurring. If <br />escapement is occurring, Reclamation will develop and implement a plan to stop <br />escapement. The plan will need to be approved by the Service prior to its <br />implementation, If it is determined that escapement is not occurring monitoring <br />will be discontinued. <br />ii) Animas River: <br />(1) The Durango Pumping Plant will divert water from the Animas River and <br />possibly entrain young fish at the plant's intake structure, Flow reductions will <br />result in a concurrent reduction in river stage that could dewater shallow nursery <br />areas used by young fish and reduce available habitat of adults. This may result in <br />long-term impacts on fish population numbers and age structure. The Durango <br />Pumping Plant intake structure will be monitored to quantify numbers of young <br />fish potentially entrained by the operation of the pumping plant. <br />(2) Monitoring studies of project-affected waters on the Animas River will be <br />implemented prior to and continue for at least four years after project operations <br />begin. The purpose of these studies will be to better define the native fishery, to <br />obtain a better understanding of native sucker recruitment, and to monitor the <br />trout populations. <br />(a) Downstream areas will be monitored to assess changes to shallow nursery <br />habitat resulting from river stage reduction attributable to Project operation. <br />Young fish will be concurrently sampled in these habitats to determine their <br />presence and relative abundance, <br />(b) The potential effect of reduced nursery habitat will be determined for native <br />fish populations by evaluating long-term demographic patterns (e,g., fish <br />species abundance, length composition, age structure, etc.). Additionally, the <br />condition and health of native fishes and stocked trout will be assessed to <br />determine water quality effects. <br /> <br />21 <br />