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levels under the same conditions may be higher. Springs are not expected to develop at the north end <br />of the 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 and the very low precipitation in 2012. The mining <br />upgradient of HI well GF-4, which occurred several years ago, has been long enough in the past to <br />allow water levels to fully recover. The water levels in this HI aquifer well seem to be varying only <br />slightly with changes in recharge rates. Water levels in this well were overall slightly higher in 2007 <br />through 2012 with the above normal precipitation except for the low 2012 value. The elevation of <br />the backfill springs likely limits the head buildup in the backfill aquifer, which, in turn, limits the <br />maximum head in the downgradient coal aquifer. Fairly steady to slightly higher water -level <br />responses were observed in the two backfill equivalent HI aquifer wells GF -5 and GF -7. Water <br />levels seem to have reached recovered levels in these two wells. The development of backfill <br />springs may limit the maximum water level in some of these areas of the A pit but the backfill <br />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 />the mined area, where levels may be limited by the elevation of backfill springs from the northern <br />pits in this area. <br />Trapper Mining Company 6 -2 <br />2012 Annual Report <br />