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slightly with changes in recharge rates. Water levels are not likely to ever recover to their • <br />pre-mine level in well GB-5. Similar water-level responses are being observed in the two <br />equivalent HI aquifer wells GF-5 and GF-7. Water levels seem to have reached recovered <br />levels in well GF-7. <br />The water levels in the three GE wells stabilized in 1990, which is thought to be <br />due to the length of time since dewatering stopped at the adjacent underground operation. <br />Some of the vaster-level rise in the last three years in wells GE-1 and GE-2 is likely due to <br />some additional recovery from mine dewatering. <br />Water levels in the backfill areas are depressed and are not likely to ever recover <br />to 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 GF- <br />11-GF-6 present water levels that are very similar in water-level elevation for the backfill • <br />and downgradient QR aquifer well. Mining is significantly increasing the permeability of the <br />mined aquifers which is a benefit relative to potential yields from the aquifer. The increased <br />permeability will likely not allow water levels to recover to pre-mine levels in the reclaimed <br />pits except near the northem (down-dip) end of the mined area, where levels will be above <br />their pre-mine level. <br />Significant drawdown has developed adjacent to the pits but the extent of these <br />drawdowns is very limited due to the small transmissivity in these aquifers. Recovery of the <br />water levels has occurred over a few years as the pits have moved away from an area. <br />Variations in natural recharge to the 2nd White Sandstone affects this aquifer <br />greatly. Mining effects on the system have not been detected. <br />6-2 <br />• <br />