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<br />system. The slightly higher precipitation in 1990 may have been <br />enough to stop the decline in the QR aquifer in this area. <br />Well GD3 Was installed in the backfill material upgradrent of <br />well GD2 in D pit during July 1988. Figure A-10 presents the plot <br />of data collected from well GD3. The overall decline in water <br />levels in the backfill material near well GD3 indicate that this <br />aquifer is sensitive to the decline in precipitation. <br />Figures A-11, A-12 and A-13 present the water-level changes <br />• <br /> <br />in the QR, HI, and Third and Second White Sandstone aquifers, <br />respectively, at the GE site. Water levels in the QR and HI <br />aquifers have shown little change in 1990. Levels in the Third and <br />Second White Sandstone aquifer rose above the 1987 levels during <br />1988 and 1989. The second half of 1990 levels show a decline from <br />the values observed in the first half of the year. Water-level <br />rises have been much less in the Third and Second White Sandstone <br />and the greatest in the QR aquifer in this area. Mining has <br />occurred within 2000 feet of these wells in an adjacent underground <br />permit, while the closest mining in Trapper's B and C pits is <br />approximately 2400 feet from these wells. The majority of the <br />drawdowns observed at these wells were probably not from Trapper <br />Mine dewatering. The reduction in the rate of recovery of water <br />level should gradually occur as the length of time since <br />dewatering increases. This is likely the cause of the slower <br />rates of water-level recovery in the'GE wells, but the decline in <br />precipitation and/or the dewatering that started in the C pit in <br />1988 could be a cause. <br />2-8 <br />