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The mining upgradient of HI Wells GB5 and GF4, Which occurred <br />several years ago, has been allowing the water levels in the HI <br />aquifer to rise. Some of this rise could be above pre-mine levels <br />since these wells are downgradient of the mining. The water-levels <br />in this area have been fairly steady the last four years. Water <br />levels in these two wells may have fully recovered. A slight <br />increase was observed during 1993 in response to increased <br />precipitation. <br />The water levels in the three GE wells stabilized in 1990, <br />which is thought to be due to the length of time since deuatering <br />stopped at the adjacent underground operation. <br />Water levels in the backfill areas are depressed and are not <br />likely to ever recover to pre-mine levels. Map 2-1 shows that the <br />levels in the backfill and downgradient aquifers are close. Well <br />pairs GD3-GD2 and GF11-GF6 present water levels that are very close <br />in water-level elevation for the backfill and downgradient QR <br />aquifer well. Mining is significantly increasing the permeability <br />of the mined aquifers which is a benefit relative to potential <br />yields from the aquifer. The increased permeability will likely <br />not allow water levels to recover to pre-mine levels in the <br />reclaimed pits except near the northern {down-dip) end of the mined <br />area, where levels will be above their pre-mine level. Water <br />levels in the native aquifer downgradient of the mining will likely <br />stabilize above their pre-mine levels. <br />The conductivity of water in backfill wells GD3, GFS, and GF11 <br />are somewhat higher but similar to those of the native aquifers in • <br />6-2 <br />