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Significant drawdown has developed adjacent to the pits but the extent of these drawdowns <br />is very limited due to the small transmissivity in these aquifers. Recovery of the water levels has <br />occurred over a few years as the pits have moved away from an area. Some water levels will likely <br />not recover to their pre -mine levels due to the different flow characteristics developed with the <br />backfill aquifer and the controlling of the maximum head by backfill springs <br />Variations in natural recharge to the 2nd White Sandstone affect this aquifer greatly. Mining <br />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 similar to <br />those of the native aquifers in these areas. TDS for GF -5 is approximately 1.5 times the pre -mine <br />value but is within natural variability of this aquifer. TDS values for backfill wells GF -7 and GF -11 <br />are much higher than the naturally observed concentrations. TDS in well GF -7 has shown some <br />decline from the peak values in the early 1990's and has been fairly steady for the last fifteen years at <br />a slightly lower level. The TDS values in well GF -11 may have reached its peak in 2001, currently <br />values are much lower than its peak and have been relatively steady from 2006 through 2012. It is <br />likely that the TDS will remain higher for many years before returning to pre -mine concentrations in <br />these two wells. The change in major constituent concentration in water in these two wells will <br />likely decrease during wet cycles and gradually decline as readily soluble constituents are removed. <br />The water quality in QR wells GD -2 and GF -6 has been only slightly affected, if at all, by the <br />upgradient mining. The remainder of the QR wells are located away from present mining activities <br />and likely not affected. <br />The water quality in HI aquifer well GP -3, which is close to the reclaimed A pit, has not <br />been influenced by mining. TDS concentrations were steady for the last few years in well GF-4 after <br />a slight increase for several previous years. This small change may be due to mining but is within <br />Trapper Mining Company 6 -3 <br />2012 Annual Report <br />