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2.1 GROUND WATER-LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 2001 included the continued expansion of the A <br />and D pit areas. Mining also wntinued in the M and Q seams in the F (Flintlock) pit, which <br />started in 1997. Mining was initiated in 2001 in the G pit (L, M and Q seams) and Z pit (I <br />seam). Pit D dewatering was 1.24 ac-ft in 2001, while the F and A pits dewatering were <br />11.79 and 16.20 ac-ft, respectively. <br />Annual precipitation for 2001 was less than normal at 13.14 inches, compared to <br />the Trapper record and also less than the long-term remrd average (Figure 2-1). The last <br />four years of precipitation have been below normal, relative to the Trapper average <br />established since 1978 (see Figure 2-1). The three years previous to the last four years <br />were above the Trapper average. Recharge in this geographic setting is directly related to <br />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 larger decline in water level in the second <br />half of 2001 due to less predpitation. The effects on the 3rd White aquifer are observed in <br />wells GC-2 and GP-9. These wells show a very gradual water-level decline in 2001, <br />showing the natural response to four years of slightly below average precipitation. The HI <br />aquifer (GP-7) is characterized by fairly gradual water-level decline in this aquifer in 2001. <br />The KLM aquifer showed a larger water-level decline in 2001 in well GP-8. The QR aquifer <br />water levels (GP-1) also showed a larger decline in 2001, which could be natural even <br />2-2 <br />