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installation of backfill wells GD3 and GF11 have defined the <br />depressed elevations in the backfill areas. The wells in this area <br />have experienced significant water-level increases ranging from 10 <br />to 28 ft. during 1993. The recovery of upgradient backfill, an <br />increase in recharge, and the decrease in dewatering in D pit are <br />all factors contributing to this change. The backfill water levels <br />will likely stabilize lower than the pre-mine levels due to the <br />increased permeability of the backfill aquifer which allows the <br />water in the aquifer to be transmitted at a lower gradient. The <br />gradient calculated for the backfill near D pit is 0.087 ft/ft <br />compared to the undisturbed gradient of 0.14 near well GP6. The <br />heads in the northern end of the backfill aquifer will likely <br />recover above the pre-mine level. Table 2-1 of the 1990 Annual <br />Hydrologic report (Hydro-Engineering, 1991) presents aquifer • <br />properties a~t Trapper Mine. The permeabilities from the backfill <br />aquifers are significantly greater than the coal aquifers which <br />they replace. <br />Additional drawdown east of D pit and the overall water-level <br />rise on the west side are the main changes in the QR water-level <br />map at Trapper Mine. Small water level increases near wells GP5 <br />and GP1 have slightly affected the contours near these wells. <br />Gradients and flow directions for the QR aquifer in 1993 are <br />similar to those observed in 1992. <br />Map No. 2-2 presents the water-level elevation contours for <br />the HI aquifer in the fall of 1993. Wells GB5, GC1, GE2, GF4, GP3, <br />GP7, and GMP-1 which are completed in the HI aquifer, and backfill <br />2-12 <br />