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estimated drawdown distances was performed for the Overburden and the 4ladge Coal aquifers . <br />(see Tab 17, Cround Water Inflows to Pits and Drawdowns). A summary of the pumpage rates <br />and drawdown distances for the two aquifers is presented in Table 17-4. A map of one-foot <br />drawdown distances for both aquifers is contained in Exhibit 17-1, The drawdown contour <br />map indicates that the predicted overburden one-foot drawdown contour is located primarily <br />within the Seneca II=H Mine leasehold area. The estimated one-foot drawdown contour fur <br />the Wadge Coal is located less than three hundred feet beyond the pit excavation boundary <br />and is situated well within the Seneca II-W leasehold. Exhibit 16-1 depicts the location <br />of righted and unrighted water sources in the Seneca II-W area. <br />Adjacent water users identified in Tab 16 will not be impacted by pit pumpage drawdovm <br />because the water sources will either be removed by mining or undisturbed, and sources <br />that are removed or impacted will be replaced according to the terms of the agreements <br />shown in Appendix 16-1, Those water sources that will be removed by mining are Temple <br />Pond No. 2, Temple Well No. 1, and the Frank Temple Stock Pond. Temple Pond No. 1 will <br />not be disturbed by the mining operation or pit pumpage drawdown, but will be replaced if <br />necessary. Peabody's Well No. 1 will not be impacted by pit pumpage drawdown because it <br />produces from a hydraulically separate aquifer well below the base elevation of the mine • <br />pit. <br />Production Well Impacts on Adjacent Water Users. A computer simulation of the effects of <br />the Peabody production well pumpage on st reamflow was performed (see Attachment 16-B). <br />The model simulated hydraulic conditions that would compute maximum pumpage and drawdown <br />in the Trout Creek Sandstone for a 15 year pumping period and a 25 year recovery period. <br />The predicted maximum drawdown of 172 feet was tabulated for the end of the 15 year <br />pumping period. The predicted maximum drawdown of 12.5 feet was tabulated for the end of <br />the 25 year recovery period. Maximum radial distances for the pumping well cone of <br />influence were predicted to be 2,5 miles at the one-foot drawdown level, 1,5 miles at the <br />25-foot drawdown level, and less than 1 mile at the 50-foot drawdown level. Drawdown is <br />directed toward the west and southwest area of the mine where the Trout Creek occurs at <br />greater depths (over 600 feet). The total estimated stream depletion for the region from <br />the production well operation was computed to be less than 1,5 percent. <br />The results from the computer model support the conclusion that the production well impact <br />on adjacent users will be minimal and of little significance. There are no wells other • <br />than Peabody's Well No. 1 that produce from the Trout Creek Sandstone, so there is no <br />14 <br />