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o "',f) ,"-I ~...j :-) (~ The first step of the project was to establish a series of observation wells in both the shallow and artesian aquifers surrounding all salvage areas of the Closed Basin. The wells would mmd.tor the effects of the project on water levels of those aquifers. Many wells suited to observe project effects were already available in the shallow aquifer. Most of the observation wells Were drilled in the confined aquifer to assure that the project is not significantly affecting the artesian. Regular monitoring of the water level.s yi.elds background information on which to base project operation. Another item of high priority was to drill and pump test wells. This involved pump testing from wells constructed specifically for this purpose. The pump tests collected data on aquifer characteristics. This information was required for well field design. Pump testing involves continuous pumping at a constant rate over a period of several days. Observation wells surrounding the pumped well are measured at the same time to catalog drawdowns. In connection with this program, tests for leakage from the confined aquifer were performed. These tests measure the effect on the artesian aquifer from pumping the shallow aquifer. The artesian was not significantly affected by pumping from the shallow aquifer'. During the spring of 1976, water quality monitoring from the observation well network began. This monitoring has continued throughout preconstruction and construction, and will continue throughout the life of the project. After the pump testing and confined aquifer testing, models were constructed based on the information gathered in the testing phase of the project. The models provided a basis for designing the pumping capacities and spacing of wells. Each stage of the Closed Basin Division has been designed using data from the preceding stages. These data are computer modeled to determine maximum water yield without excessive drawdown in the salvage area. .No excessive drawdown means no significant effect on the artesian aquifer; and that pumping will not affect the water table in existing wells outside the salvage areas by more than two feet. These effects are precluded by law. An environmental impact statement waS prepared as required by the National Environmental Policy Act of 1969. This impact statement presents a project description and evaluation of its environmental costs and benefits. This docu- ment considers the overall environment, including fish and wildlife, archeology, and social effects. The existing environment and the future environment, both with and without the proposal, were described. The statement was filed with the Council on Environmental Quality. During the 90-day review period which followed, the public was invited to comment on the proposed project. Public hearings were held' in Saguache and Alamosa. The draft and final environmental impact statements, the public comments on them, and the Bureau's responses are public documents. -'4- -