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-33- <br />The applicant has predicted the maximum rate of inflow at the Maxwell Mine to <br />reach 180 gpm. Since dewatering of the coal aquifer at the Allen Mine has <br />been occurring for a number of years, the maximum discharge is predicted to be <br />less than that predicted at the Maxwell Mine. <br />The average mine discharges measured in the third quarter of 1983 at the Allen <br />Mine are higher than those measured when the hydrologic report in Exhibit 6 <br />was prepared. The present discharge rate is 123 gpm, whereas the previously <br />reported discharge rate was 73 gpm. This increased discharge rate can be <br />attributed to the additional mining which occurred after preparation of the <br />hydrologic report and the present inactivity of the mine. The additional <br />mining resulted in increased area of inflow. During mining, water was <br />consumed as adsorbed water on coal exiting the mine, and in increased humidity <br />in the ventilation air. Currently, coal is not exiting the mine, and <br />ventilation air volumes are reduced. <br />Mining activity will affect the stream/alluvial aquifer system of the Middle <br />Fork of the Purgatoire River. The Allen and Maxwell coal seam aquifer <br />subcrops below the Middle Fork of the Purgatoire River and in Pete Canyon, <br />north of the Allen Mine. These streams and their alluvial aquifers may <br />recharge the coal aquifer. The underground mine workings may deplete the <br />stream/alluvial aquifer systems through increased recharge at subcrops and <br />outcrops of the coal aquifers. Depletion of stream/alluvial aquifer systems <br />may also occur as a result of drying up of aquifer discharges (springs and <br />seeps). The applicant has predicted that the stream/alluvial aquifer system <br />will be depleted by vertical leakage of surface waters through the overburden <br />strata into the mine cavity. <br />for the Maxwell Mine, downward flow through the overburden in the absence of <br />open fractures or subsidence was calculated to be less than 3 gpm, an <br />insignificant portion of flow in the Purgatoire River stream-alluvial aquifer <br />system. Inspection of underground workings in the Aiien Mine beneath the <br />Middle Fork by Division personnel did not identify significant inflows of <br />ground water that could be attributed to leakage through the roof from the <br />stream/alluvial aquifer system. <br />An inflow study for the Allen Mine was conducted in November of 1983. This <br />study consisted of the mapping of all measurable mine inflows on a mine <br />workings map, measuring or estimating inflow rates, and determining inflow <br />sources. The information on Allen Mine inflows is contained in the WFC <br />submittal 3, and on the Allen Mine Map, both submitted December 1, 1983. <br />Mine inflows are not concentrated in areas of the Allen Mine which are <br />overlain by streams, but are dispersed throughout the mine. Thus, the mine is <br />not inducing stream or alluvial ground water depletions direct]y through the <br />overburden strata. <br />The mapping of mine inflows indicate that faults and fractures are not a <br />source of mine inflows. No point source inflows were observed along faults <br />and fractures. This indicates that faults and fractures are healed with <br />impermeable clays and/or are not vertically extensive. <br />