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2.1 GROUND WATER-LEVEL CHANGES • <br />2.1.1 SUMMARY <br />Significant mine activities during 2002 included the continued expansion of the A <br />pit and the completion of the D pit. Mining also continued in the M and Q seams in the F <br />(Flintlock) pit, which started in 1997. Mining was initiated in 2001 in the G pit (H, L, M and <br />Q seams in 2002) and Z pit (I seam in 2002) and continued in 2002. Dewatering did not <br />occur in Pit D in 2002, while the F and A pits dewatering were 4.05 and 12.71 ac-ft, <br />respectively. Well dewatering of 3.34 ac-ft was initiated in 2002 near the G pit. <br />Annual precipitation for 2002 was less than normal at 11.19 inches, compared to <br />the Trapper record and also less than the long-term record average for the last two years <br />(Figure 2-1). The last five years of precipitation have been below normal, relative to the <br />Trapper average established since 1978 (see Figure 2-1}. The three years previous to the <br />last five 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 larger variation in water level in 2002 due <br />to ground recharge from the lower precipitation year. The effects on the 3rd White aquifer <br />are observed in wells GC-2 and GP-9. These wells show a very gradual water-level rise in <br />2002, showing good recharge with the below average precipitation. The HI aquifer (GP-7} <br />is characterized by fairly gradual water-level decline in this aquifer in 2002. The KLM <br />aquifer showed a larger water-level decline in 2001 in well GP-8. The QR aquifer water . <br />2-2 <br />