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undisturbed gradient of 0.14 ft/ft near well GP-6. The heads in the northern end of the <br />backfill aquifer will likely recover above the pre-mine level. Backfill springs are not <br />expected to develop near the northern end of the QR backfill because backfill water levels <br />would have to recover greater than a few tens of feet to reach the lower land surface <br />elevations. Table 2-1 of the 1990 Annual Hydrologic Report (Hydro-Engineering, 1991} <br />presents aquifer properties at Trapper Mine. The permeabilities from the backfill aquifers <br />are significantly greater than the coal aquifers that they replace. <br />The QR water-level map at Trapper Mine was very similar in 2002 to the 2001 <br />water-level elevations except for some decline in the water-level elevations in the area of <br />well GP-1. Gradients and flow directions for the QR aquifer in 2002 are similar to those <br />observed in 2001. <br />Map No. 2-2 presents the water-level elevation contours for the HI aquifer in the <br />Fall of 2002. Wells GB-5, GC-1, GE-2, GF-4, GP-3, GP-7, and GMP-1, which are completed <br />in the HI aquifer, and backfill wells GF-5 and GF-7, were used in the development of this <br />map. Welts GF-5 and GF-7 are completed in the backfill in the area where the H and I coal <br />seams were mined. Flow direction in the HI aquifer has been changed mainly near the A <br />pit near well GF-4. The overall flow regime in this aquifer is nortlierly, similar to that <br />observed in 2001 (see Hydro-Engineering, 2002). The ground-water gradient between the <br />backfill aquifer and the un-mined HI aquifer downgradient is relatively flat as it is in the QR <br />backfill. The contours in the HI aquifer have also been changed on the east side where <br />the active A pit was extended in 2002, mining the H seam. The Z pit was used to mine the <br />I seam in 2002. <br />The 3rd White Sandstone aquifer water-level elevations are presented on Map <br />No. 2-3. Wells GB-2, GC-2, GE-3, P-8, 81-03A, and GP-9 were used in the development of <br />2-10 <br />