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• permeability of the backfill aquifers which is a benefit relative to potential yields from the aquifer. The increased permeability will likely not allow water levels to recover to pre-mine levels in the reclaimed pits except near the northern (down-dip) end of the mined area, where levels may be limited by the elevation of backfill springs in this area. Significant drawdown has developed adjacent to the pits but the extent of these drawdowns is very limited due to the small transmissivity in these aquifers. Recovery of the water levels has occurred over a few years as the pits have moved away from an area. Sorne water levels will likely not recover to their pre-mine levels due to the different flow characteristics developed with the backfifl aquifer and the controlling of the maximum head by backfill springs. Variations in natural recharge to the 2nd White Sandstone affects this aquifer • greatly. Mining.effects on the system have not been detected. The TDS of water in backfill wells GD-3 and GF5 are somewhat higher but similar to those of the native aquifers in these areas. TDS for GF-5 is approximately 1.5 times the pre-mine value but is within natural variability of this aquifer. TDS values for backfill wells GF-7 and GF-S1 are much higher than the naturally observed concentrations, TDS in well GF-7 has shown some decline from the peak values in the early 1990's, Additional monitoring will be needed to determine whether the TDS in backfill well GF-7 is gradually declining to the pre-mine level. The TDS in well GF-11 is lower but still increasing with time. It is likely that the lUS will remain higher for many years before returning to pre-mine concentrations in these two wells. The change in major constituent concentration in water in these two wells will likely gradually decline as readily soluble • constituents are removed. The water quality in QR wells GD-2 and GF-6 has been only 6-3