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The GLIJX-1 well water level plot (Figure A-38) is very similaz to the nearby 81-03a well. The GLUX-1 is completed in the Ist White Sandstone aquifer; 81-03a in the 3rd White. It is shallower than the 8]-03a, which may account for the increase in the spring of 1994. Well GMP-1 was completed in the HI aquifer to monitor ground-water conditions downgradient of the ash disposal site immediately south of A pit. Water levels have continued the increase begun in 199? and, as in 1993, is up approximately 4.5 fr. during this report period. 2.2 GROUND WATER-LEVEL ELEVATION (PIEZOMETRIC MAP SUMMARl~ Hydro-Engineering developed three piezomettic maps to show the water level flow patterns for the QR, HI and 3rd White Sandstone aquifers at Trapper Mine. Water levels from the 3rd quarter of 1994 were used to develop these maps. Map No. 2-1 presents the water-level elevations for the QR aquifer. The water-level elevation is presented for the QR wells: GA1, GD2, GE1, GF6, GPI, GPS, and GP6 and backfill wells GD3 and GFl 1. The ground-water flow in the QR aquifer is mainly to the north. Mining has only affected the QR aquifer close to the D and E pits by causing drawdowns very near the pit edges. The installation of backfill wells GD3 and GF11 have defined the depressed elevations in the backfill areas. The wells in this area have continued to experience water-level increases ranging from 2 to 4 ft. during 1994. The recovery of upgradient backfill and the decrease in dewatering in D pit are all factors contributing to this change. The backfill water levels will likely stabilize lower than the pre-mine levels due to the increased permeability of the backfill aquifer which allows the water in the aquifer to be transmitted at a lower gradient. The gradient calculated for the backfill neaz D pit is 0.087 ft/ft compared to the undisturbed gradient of 0.14 near well GP6. The heads in ~J 2-9