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2.1 GROUND WATER-LEVEL CHANGES 2.1.1 SUMMARY Significant mine activities during 2005 included the continued expansion of the F, G and Z pits. Mining in the F pit, which started in 1997, continued in the M and Q seams with additional mining in the I and L seams in 2004 and 2005. Mining was initiated in 2001 in the G pit (H seam in 2005) and Z pit (I, L, M and Q seams in 2005). Dewatering occurred in the A and F pits during 2005 at dewatering volumes of 24.72 and 0.18 ac-ft, respectively. Well dewatering of 45.67 ac-ft was produced in 2005 neaz the G pit. Annual precipitation for 2005 was greater than normal at 18.79 inches, compazed to the Trapper record and the long-teen record (Figu~t 2-1). The previous last seven years of precipitation had been below normal, relative to the Trapper average established since 1978 (see Figure 2-1) but the 2005 average was 2.4 inches lazger. The last three yeazs were equal or above the long-term • record average. Recharge in this geographic setting is directly related to precipitation. • The effects of natural recharge variations on the respective aquifers can be observed in wells located in undisturbed azeas away from the influence of mining activities. Wells GC-2, GC-3 and GP-9 aze used to indicate natural response in the past but need to be used with caution starting in 2000 due to mining moving into this area. Well GC-3 exhibited the alluvial water-level response with a similar variation in water level in 2005 to those that have been observed historically. The effects on the 3rd White Sandstone aquifer aze observed in wells GC-2 and GP-9. Well GP-9 shows a water-level rise in 2005, showing good recharge with the above average precipitation while water levels gradually increased in well GC-2. The HI aquifer (GP-7) is characterized by fairly gradual water-level decline in this aquifer in 2005. The KLM aquifer showed a larger water-level decline in Trapper Mining Company 2-2 2005 Annual Repoli