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2.1 GROUND WATER-LEVEL CHANGES • <br />2.1.1 SUMMARY <br />Significant mine activities during 2000 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 10.16 ac-ft in 2000, while the F and A pits <br />dewatering were 30.56 and 4.37 ac-ft, respectively. <br />Annual precipitation for 2000 was slightly less than normal at 15.93 inches, <br />compared to the Trapper record and above the long-term record average (Figure 2-1). <br />The last three years of precipitation have been near normal, relative to the Trapper <br />average established since 1978 (see Figure 2-1). The three years previous to the last <br />three years were above the Trapper average. 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 />Wells GC-2, GC-3 and GP-9 are used to indicate natural response in the past but need to <br />be used with caution starting in 2000 due to mining moving into this area. Well GC-3 <br />exhibited the alluvial water-level response with a similar water-level change in 2000 to that <br />observed in 1999. The effects on the 3rd White aquifer are observed in wells GC-2 and <br />GP-9. These wells show a very gradual water-level decline in 2000, showing the natural <br />response to three years of slightly below average precipitation. The HI aquifer (GP-7) is <br />characterized by fairly gradual water-level decline in this aquifer in 2000. The KLM aquifer <br />showed gradual water-level decline in 2000 in well GP-8. The QR aquifer water levels (GP- <br />• <br />2-2 <br />