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2.1 GROUND WATER -LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 2017 included the continued expansion of the L pit. <br />Mining in the F pit, which started in 1997, ceased mining in 2011 with only reclamation activities in <br />2012 through 2017 in this area. Mining was initiated in 2001 in the G pit, which was idle in 2010 <br />through 2017. The K pit was mined in the K, MK, LK, ML, LL, M, Q and R seams in 2015 with <br />only reclamation activities in 2017. L pit mined in seams H, H1, H2, I1, I2, K, MK, LK, ML, M, <br />MM, LM, Q, UQ and MQ seams in 2017. Dewatering occurred in only the L pit during 2017 with a <br />volume of 12.21 ac -ft pumped. Well dewatering of 50.92 ac -ft was produced in 2017 near the G pit. <br />Annual precipitation for 2017 was above normal at 18.86 inches, compared to the Trapper <br />record and long-term record (Figure 2-1). The 2006, 2007, 2008, 2010, 2011 and 2017 precipitation <br />were above normal while the 2012 precipitation was significantly below normal, the 2013 <br />precipitation at normal, the 2014 and 2015 slightly above normal and the 2016 below normal, <br />relative to the Trapper average since 1978 (see Figure 2-1). The last year was above normal, <br />previous year below normal and the prior three years were significantly above the long-term record <br />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 fairly steady water levels in 2017. The effects on the 3rd White Sandstone aquifer are observed <br />in wells GC -2 and GP -9. Wells GC -2 and GP -9 show an overall a very slight water level rise in <br />Trapper Mining Company 2-2 <br />2017 Annual Report <br />