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• reclaimed pits except near the northern (down-dip) end of the mined area, where levels <br /> may be limited by the elevation of backfill springs in this area. <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 <br /> the water levels has occurred over a few years as the pits have moved away from an area. <br /> Some water levels will likely not recover to their pre-mine levels due to the different flow <br /> characteristics developed with the backfill aquifer and the controlling of the maximum head <br /> by backfill springs. <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 /> The TDS of water in backfill wells GD-3 and GF-5 are somewhat higher but <br /> . similar to those of the native aquifers in these areas. TDS for GF-5 is approximately 1.5 <br /> times the pre-mine value but is within natural variability of this aquifer. TDS values for <br /> backfill wells GF-7 and GF-11 are much higher than the naturally observed concentrations. <br /> TDS in well GF-7 has shown some decline from the peak values in the early 1990's. <br /> Additional monitoring will be needed to determine whether the TDS in backfill well GF-7 is <br /> gradually declining to the pre-mine level. The TDS in well GF-11 is lower but still <br /> increasing with time. It is likely that the TDS will remain higher for many years before <br /> returning to pre-mine concentrations in these two wells. The change in major constituent <br /> concentration in water in these two wells will likely gradually decline as readily soluble <br /> constituents are removed. The water quality in QR wells GD-2 and GF-6 has been only <br /> slightly affected, if at all, by the upgradient mining. The 1999 TDS values for well GE-1 <br /> • declined to close to their pre 1990's values. These changes are within natural variations <br /> 6-3 <br />