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2.1 GROUND WATER-LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 2003 included the wntinued expansion of the A <br />pit Mining also continued in the M and Q seams in the F (Flirrtlodc) pit, which started in <br />1997. Mining was initiated in 2001 in the G pit (H, L, M and Q seams in 2003) and Z pit (I <br />seam in 2003). Dewatering occurred in the F, A, G and Z pits during 2003 at dewatering of <br />2.07, 15.61, 4.92 and 0.12 ac-ft, respectively. Well dewatering of 31.49ac-ft was produced <br />in 2003 near the G pit. <br />Annual precipitation for 2003 was slightly less than normal at 14.14 inches, <br />compared to the Trapper record and slightly greater than the long-term record (Figure 2-1). <br />The last sDc 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 six years were <br /> <br />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 undisturf~ed areas away from the influence of mining activities. <br />Wells GG2, GC-3 and GP-9 are used to indigte natu2l response in the past but need to be <br />used with potion starting in 2000 due to mining moving into this area. Well GG3 exhibited <br />the alluvial water-level response with a similar variation in water level in 2003 to those that <br />have been observed h'~storicalry. The effeds on the 3rd White aquifer are observed in wells <br />GC-2 and GP-9. These wells show a very gradual water-level rise in 2003, showing good <br />recharge wrth the slightly below average precipitation. The HI aquifer (GP-7) is <br />characterized by fairly gradual water-level decline in this aquifer in 2003. The KLM aquifer <br />showed a larger water-level decline in 2001 in well GP-8 and continued on a smaller decline <br />~_ <br />2-2 <br />