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RESULTS <br />Stream Depletions <br />The modeling indicates that long-term pumpage at both proposed mines will cause <br />stream depletions at the following outcrop areas in: upper and lower Sage Creek, <br />Sage Creek Reservoir, Grassy Creek, Middle Creek, Trout Creek, and in the Yampa <br />River above Grassy Creek (Tables 1, 2 and 3). Stream depletion will not occur in <br />Dry Creek because 1) the flow in Hubberson Gulch is intermittent where it crosses <br />the outcrop of the Trout Creek Sandstone, and 2) the sandstone, which dips <br />approximately 11° to the north directly west of IIW where Hubberson Gulch <br />intercepts Dry Creek, is buried approximately 600 feet or more beneath the Williams <br />Fork formation. <br />Three separate simulations were performed. The first simulation considered only the <br />• <br />pumpage from the Seneca IIW well (Figures 4a, 4b, Sa, and Sb). The second • <br />considered only the pumpage from the Yoast well (Figures 6a, 6b, 7a, and 7b). The <br />third included the combined effect of the Seneca IIW and Yoast wells. The Seneca <br />IIW well is turned on at the beginning of mining (1990) and is pumped for 15 years; <br />the Yoast well is turned on at the beginning of the sixth year of mining (1996), and <br />is turned off at the same time as the Seneca IIW well, at the end of mining in year <br />2004 (Figures 8a, Sb, 9a, and 9b). In all three simulations, 20 years of recovery were <br />simulated to the end of year 2024 (Figures l0a and 106). <br />The maximum depletion in all affected streams equals 10.88 % (or 12.36 ac-ft/yr) of <br />the total pumpage for both wells and occurs at the end of mining, simulation year 15, <br />when both wells have been pumping (Figures 9a and 9b). The highest individual <br />stream depletion during this time occurs in Grassy Creek and is projected to be 5.1% <br />6 • <br />