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2.1 GROUND WATER-LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 2012 included the continued expansion of the K and Z <br />pits. Mining in the F pit, which started in 1997, ceased mining in 2011 with only reclamation <br />activities in 2012 in this area. Mining was initiated in 2001 in the G pit, which was idle in 2010 <br />through 2012. The K pit was mined in the H, I, I1, 12, K, LK, ML, LL, M, MM, LM, Q and R seams <br />in 2012. Z pit is mined in seams I, K, L, M and Q seams in 2008 and 2009, with only the Q seam <br />continuing in 2010 through 2012. Dewatering occurred in the Z and G pits during 2012 at dewatering <br />volume of 1.43 and 49.16 ac -ft, respectively. Well dewatering of 49.63 ac -ft was produced in 2012 <br />near the G pit. <br />Annual precipitation for 2012 was below normal at 10.70 inches, compared to the Trapper <br />record and the long -term record (Figure 2 -1). The 2006, 2007, 2008, 2010 and 2011 precipitation <br />were above normal while the 2012 precipitation is significantly below normal, relative to the Trapper <br />average since 1978 (see Figure 2 -1). The previous six years were significantly above the long -term <br />record average. 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 in <br />2000 due to mining moving into this area. Well GC -3 exhibited the alluvial water -level response <br />with a gradual decline in water level in 2012. The effects on the 3rd White Sandstone aquifer are <br />observed in wells GC -2 and GP -9. Welts GC -2 and GP -9 show an overall fairly steady water level in <br />2012 showing minimum affects from the below average precipitation year due to the above average <br />previous precipitation for the last few years. The HI aquifer (GP -7) is characterized by a very <br />gradual decline in 2012 after steady water levels for the previous years. The KLM aquifer showed a <br />Trapper Mining Company 2 -2 <br />2012 Annual Report <br />