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2.1 GROUND WATER -LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 2006 included the continued expansion of the A, F, G <br />and Z pits. Mining in the F pit, which started in 1997, continued in the M and Q seams with <br />additional mining in the I and L seams in 2004 through 2006. Mining was initiated in 2001 in the <br />G pit (H, I and K seams in 2006) and Z pit (I, L, M and Q seams in 2006). Dewatering occurred in <br />the A, F and G pits during 2006 at dewatering volumes of 20.53, 5.57 and 2.55 ac -ft, respectively. <br />Well dewatering of 47.22 ac -ft was produced in 2006 near the G pit. <br />Annual precipitation for 2006 was greater than normal at 17.18 inches, compared to the <br />Trapper record and the long -term record (Figure 2 -1). The 2005 precipitation was also above <br />normal while the previous seven years of precipitation had been below normal, relative to the <br />Trapper average established since 1978 (see Figure 2 -1). The 2006 average was 0.8 inches larger <br />than the Trapper average. The last three years were equal or above the long -term record average. <br />Recharge in this geographic setting is directly related to precipitation. <br />The effects of natural recharge variations on the respective aquifers can be observed in <br />wells located in undisturbed areas away from the influence of mining activities. Wells GC -2, GC -3 <br />and GP -9 are used to indicate natural response in the past but need to be used with caution starting <br />in 2000 due to mining moving into this area. Well GC -3 exhibited the alluvial water -level response <br />with a similar variation in water level in 2006 to those that have been observed historically. The <br />effects on the 3rd White Sandstone aquifer are observed in wells GC -2 and GP -9. Well GP -9 <br />shows a water -level rise in 2006, showing good recharge with the above average precipitation while <br />water levels were steady in well GC -2. The HI aquifer (GP -7) is characterized by a water -level <br />decline in this aquifer in 2006. The KLM aquifer showed a larger water -level decline in 2001 in <br />Trapper Mining Company 2 -2 <br />2006 Annual Report <br />