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f <br /> The water-level changes for the HI aquifer have generally been influenced less by <br /> slightly less than average recharge during the last two years. The mining upgradient of HI <br /> wells GB-5 and GF-4, which occurred several years ago, has been long enough in the past <br /> to allow water to fully recover. The water levels in these HI aquifer wells seem to be <br /> varying only slightly with changes in recharge rates. Water levels are not likely to ever <br /> recover to their pre-mine level in well GB-5. The elevation of the backfill springs likely <br /> limits the head buildup in the backfill aquifer, which, in turn, limits the maximum head in <br /> the downgradient coal aquifer. Similar water-level responses are being observed in the <br /> two backfill equivalent HI aquifer wells GF-5 and GF-7. Water levels seem to have reached <br /> recovered levels in these two wells. The development of backfill springs may limit the <br /> maximum water level in some of these areas of the A pit. <br /> The water levels in the three GE wells stabilized in approximately 1990. This is • <br /> thought to be due to the length of time since dewatering stopped at the adjacent <br /> underground operation. The additional water-level rise in the last five years in wells GE-1 <br /> and GE-2 is likely due to increased recharge and some additional recovery from mine <br /> dewatering. <br /> Water levels in the backfill areas are depressed and are not likely to ever recover to <br /> pre-mine levels except near the northern end of the mine area. Map 2-1 shows that the <br /> levels in the backfill and downgradient aquifers are similar. Well pairs GD-3 & GD-2 and <br /> GF-11 & GF-6 present water levels that are very similar in water-level elevation for the <br /> backfill and downgradient QR aquifer well. Mining is significantly increasing the <br /> permeability of the backfill aquifers which is a benefit relative to potential yields from the <br /> aquifer. The increased permeability will likely not allow water levels to recover to pre-mine •\ <br /> 6-2 <br />