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Figure A-15 presents the change in water-level elevation for alluvial well P-1, <br />located in the Pyeatt drainage north of the PA. This data demonstrates classic seasonal <br />responses, highs in winter/spring and lows in late summer/fa!!. An overall gradua! decline <br />in water levels occurred the last few years. Well P-3 is completed in the Lewis Shale <br />outcrop, which is in contact with the Pyeatt alluvium. It demonstrates the same seasonal <br />variations (Figure A-15} as the P-1 well. <br />Water-level elevations for the Johnson Gulch alluvial well J-1 are also presented <br />in Figure A-25. The J-1 water levels remained steady in 2002. <br />2.2 GROUND WATER-LEVEL ELEVATION (PIE2OMETRIC MAP SUMMARlf7 <br />Hydro-Engineering developed three piezometric maps to show the water level <br />flow patterns for the QR, HI and 3rd White Sandstone aquifers at Trapper Mine. Water <br />levels from the Fall of 2002 were used to develop these maps. <br />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-ti, GP-1, GP-5, and GP- <br />6 and backfill wells GD-3 and GF-li. 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, F and G pits by <br />causing drawdowns very near the pit edges. The installation of backfill wells GD-3 and GF <br />11 has defined the depressed elevations in the backfill areas. The wells in this area <br />experienced fairly steady to gradual declining levels during 2002. The gradual declines and <br />steady levels are likely due to less recharge in the last five years. The backfill water levels <br />will likely stabilize lower than the pre-mine levels due to the increased permeability of the <br />bacldilt aquifer, which allows the water in the aquifer to be transmitted at a lower gradient. <br />. The gradient calculated for the backfill near D pit is 0.008 ft/ft, compared to the <br />2-9 <br />