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well GD -2 in 1998 than those observed in 1986 after six wet years indicates the post -mine levels <br />under the same conditions may be higher. Springs are not expected to develop at the north end of the <br />D, F and K pits. <br />The water -level changes for the HI aquifer have generally been influenced less by higher than <br />average recharge in 2005 through 2011, the very low precipitation in 2012, and closer to normal in <br />2013. The mining upgradient of HI well GF-4, which occurred several years ago, has been long <br />enough in the past to allow water levels to fully recover. The water levels in this HI aquifer well <br />seem to be varying only slightly with changes in recharge rates. Water levels in this well were overall <br />slightly higher in 2007 through 2013 with the above normal precipitation except for the low 2012 <br />value. The elevation of the backfill springs likely limits the head buildup in the backfill aquifer, <br />which, in turn, limits the maximum head in the downgradient coal aquifer. Fairly steady to slightly <br />higher water -level responses were observed in the two backfill equivalent HI aquifer wells GF -5 and <br />GF -7. Water levels seem to have reached recovered levels in these two wells. The development of <br />backfill springs may limit the maximum water level in some of these areas of the A pit but the <br />backfill aquifer will maintain less fluctuation in water levels down gradient of the pit. <br />Water levels in the backfill areas are depressed and are not likely to ever recover to pre-mine <br />levels except near the northern end of the mine area. Map 2 -1 shows that the levels in the backfill <br />and downgradient aquifers are similar. Well pairs GD -3 & GD -2 and GF -11 & GF-6 present water <br />levels that are very similar in water -level elevation for the backfill and downgradient QR aquifer <br />well. Mining is significantly increasing the permeability of the backfill aquifers which is a benefit <br />relative to potential yields from the aquifer. The increased permeability will likely not allow water <br />levels to recover to pre-mine levels in the reclaimed pits except near the northern (down -dip) end of <br />Trapper Mining Company 6 -2 <br />2013 Annual Report <br />