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• permeability aquifers have exhibited limited drawdowns in the immediate vicinity of the active pits. <br />Further, drawdowns downgradient of the active mining areas typically recover much faster than <br />expected because the increased permeability, in the backfill 'spoil aquifer transmits water to the <br />downgradient end of the pit more readily. <br />Drawdowns at KLM well GP-2, roughly 2200 feet distant from the G Strike pit boxcut, have <br />developed on the order of twenty feet, within the approximate range of predicted behavior for <br />aquifers in the area. Well dewatering activities in the G Pit area will likely maintain this slight <br />drawdown until mining is completed in the area. Drawdown recorded at QR well GP-1, some 1200 <br />feet away from the boxcut, was observed at approximately 40 feet before GP-1 was disturbed by <br />mining in early 2003. <br />Wells GC-1 and GC-2, completed in the HI and 3rd White Sandstone aquifers respectively, showed <br />only slight declines in water level when A Pit mining occurred within 1,000 feet directly upgradient <br />from the wells during the early 2000's. Water levels in these wells have since recovered to <br />premining levels. <br />IMPACTS TO ADJUDICATED WELLS (see Map M31) <br />• The Second White sandstone does not exist in Derringer pit. In Ashmore pit, the Second White <br />Sandstone is probably not saturated in the areas of the pit that will be mined during the current <br />permit term. <br />The nearest Third White sandstone well to the Ashmore pit during the permit period is slightly greater <br />than one mile to the northeast. Significant drawdowns in the Third White sandstone to the north of <br />the mine are not expected because drainage of ground water to the north end of the mine due to <br />increased permeability in the backfill aquifer will likely cause water-level rises in the Third White <br />sandstone aquifer north of the mine. No impacts are expected in Third White sandstone wells 80998 <br />and W-624-74 during the current permit term. Wells 22653F, 22654F and 22100F are completed <br />below the Twentymile Sandstone and should not be impacted by the mine dewatering. <br />• <br />4-226d <br />Revision Pe <br />Approved: