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DRAWDOWNS <br />Prediction of drawdown, which should occur based on the above estimates, would be several tens of <br />feet at one mile from the permit boundary. Observed drawdowns have been less than these <br />predictions. Actual observations of drawdowns are much more indicative of impacts. These low <br />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, had developed <br />on the order of twenty feet, well within the approximate range of predicted behavior for aquifers in the <br />area, however, current water levels have risen to pre -mine maximums. Drawdown recorded at QR <br />well GP -1, some 1200 feet away from the boxcut, was observed at approximately 40 feet before GP -1 <br />was disturbed by 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 from <br />the wells during the early 2000's. Water levels in these wells have since recovered to premining <br />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 permit <br />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 north. Significant drawdowns in the Third White sandstone to the north of the <br />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 />4-226d <br />MAY ?_ <br />� 7 013 <br />:s' isic��m <br />