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I <br /> 2.1 GROUND WATER-LEVEL CHANGES • <br /> 2.1.1 SUMMARY <br /> Significant mine activities during 1998 included the continued expansion of the A <br /> and D pit areas. Mining also continued in the M and Q seams in the F (Flintlock) pit, which <br /> started in 1997. Pit D dewatering was 52 ac-ft in 1998, while the D pit dewatering wells <br /> volume of pumping was 26 ac-ft. Dewatering in the A and H pits was 20 and 1 ac-ft, <br /> respectively, in 1998. <br /> Annual precipitation for 1998 was near normal at 16.0 inches, compared to the <br /> Trapper record and above the long-term record average (Figure 2-1). The last four years <br /> of precipitation have been above normal, relative to the long-term average estabilshed <br /> prior to mining activities (see red in Figure 2-1). Recharge in this geographic setting is <br /> directly related to precipitation. <br /> The effects of natural recharge variations on the respective aquifers can be <br /> observed in wells located in undisturbed areas away from the influence of mining activities. <br /> Well GC-3 exhibited the alluvial water level response with a water-level rise from spring <br /> recharge in 1998 followed by a gradual decline. The effects on the 3rd White aquifer are <br /> observed in wells GC-2 and GP-9. These wells show a water-level rise in 1998, showing <br /> the natural response to the above average precipitation. The HI aquifer (GC-1, GP-7) is <br /> characterized by fairly steady water levels with a small increase during the last few years. <br /> The ILM aquifer (GP-2, GP-8) has shown a gradual water-level rise in 1998 with the <br /> exception of a gradual decline at the beginning of the second half of 1998 in well GP-2. <br /> The QR aquifer response (GP-1) has been an overall rise in 1998 with increases of <br /> approximately three feet. <br /> 2-2 <br />