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Map No. 2-1 presents the water-level elevations for the QR aquifer. The <br /> water-level elevation is presented for the QR wells: GD-2, GE-1, GF-6, GP-1, GP-5, and GP- <br /> 6 and backfill wells GD-3 and GF-11. The ground-water flow in the QR aquifer is mainly to <br /> the north. Mining has only affected the QR aquifer close to the D, E and F pits by causing <br /> drawdowns very near the pit edges. The installation of backfill wells GD-3 and GF-11 has <br /> defined the depressed elevations in the backfill areas. The wells in this area have <br /> continued to experience water-level increases during 1998. These increases are likely due <br /> to the mining moving further away from GD-3 and the higher recharge rates during the <br /> last four years. The backfill water levels will likely stabilize lower than the pre-mine levels <br /> due to the increased permeability of the backfill aquifer which allows the water in the <br /> aquifer to be transmitted at a lower gradient. The gradient calculated for the backfill near <br /> D pit is 0.07, compared to the undisturbed gradient of 0.14 ft/ft near well GP-6. The <br /> heads in the northern end of the backfill aquifer will likely recover above the pre-mine <br /> level. Backfill springs may develop near the northern end of the backfill, limiting the <br /> maximum recovery head in the backfill aquifer. Table 2-1 of the 1990 Annual Hydrologic <br /> Report (Hydro-Engineering, 1991) presents aquifer properties at Trapper Mine. The <br /> permeabilities from the backfill aquifers are significantly greater than the coal aquifers that <br /> they replace. <br /> Additional recovery in the water levels west of the D pit and east of the E pit are <br /> the main changes in the QR water-level map at Trapper Mine. Gradients and flow <br /> directions for the QR aquifer in 1998 are similar to those observed in 1997. <br /> Map No. 2-2 presents the water-level elevation contours for the HI aquifer in the <br /> fall of 1998. Wells GB-5, GC-1, GE-2, GF-4, GP-3, GP-7, and GMP-1, which are completed <br /> 2-9 <br />