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<br />The average daily mine discharge measured during 1987 at the New Elk Mine <br />is roughly the same as that measured in 1980 when the hydrologic report <br />in Exhibit 6 was prepared, i.e., 75 gpm vs 73 gpm. While same mining was <br />done following the original study, the mine has not been actively worked <br />for several years. During mining, water was consumed by absorbtiort on <br />coal exiting the mine, and in increased humidities in the ventilation <br />air. Currently, coal is not exiting the mine and ventilation air volumes <br />are reduced, <br />Mining activity might affect the stream/alluvial aquifer system of the <br />Middle Fork of the Purgatoire River. The Allen and t+laxwell coal seam <br />aquifer subcrops below the Middle Fork of the Purgatoire River and in <br />Pete Canyon, north of the New Elk Mine. These streams and their alluvial <br />aquifers mAy recharge the coal aquifer. If so, the underground mine <br />workings mdy diminish the stream/alluvial aquifer systems through <br />increased recharge at subcrops and outcrops of the coal aquifers. <br />Dimunition of stream/alluvial aquifer systems may also occur as a result <br />of drying up of aquifer discharges (springs and seeps), Any excess water <br />entering the coal aquifer, however, is returned to the Purgatoire River <br />via the discharge of water from the mine. Asa result, impacts on <br />quantity of water available from the stream/alluvial system of the <br />Purgatoire should be minimal. <br />Impacts to Pete Canyon are expected to be short-term in nature. Once <br />mining ceases, pumpage of mine water will be stopped and the mine will <br />begin to fill. After filling of the mine, dimunition of water from the <br />surface systems of Pete Canyon should cease and flows return to <br />essentially the pre-disturbance levels. <br />The applicant has predicted that the stream/alluvial aquifer system will <br />be depleted by vertical leakage of surface waters through the overburden <br />strata into the mine cavity. For the New Elk Mine, however, downward <br />flow through the overburden in the absence of open fractures or <br />subsidence was calculated to be less than 5 gpm, an insignificant portion <br />of flow in the Purgatoire River stream-alluvial aquifer system. <br />Inspection of underground workings in the New Elk Mine beneath the Middle <br />Fork by Division personnel did not identify significant inflows of ground <br />water that could be attributed to leakage through the roof from the <br />stream/alluvial aquifer system. <br />An annual inflow study for the New Elk Mine was initiated in 1983 and <br />most recently conducted in August of 1987. This study consisted of the <br />mapping of all measurable mine inflows on a mine workings map, measuring <br />or estimating inflow rates, and determining inflow sources. The most <br />current information on the New Elk Mine inflows is contained in ExhiDlt <br />10 of the renewal application. <br />Mine inflows are not concentrated in areas of the New Elk Mine which are <br />overlain by streams, but are dispersed throughout the mine. Thus, the <br />mine does not appear to have significant direct connection with the <br />stream or alluvial system. <br />_P2 _ <br />