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• GD3-GD2 and GFll-GF6 present water levels that are very close in <br /> water-level elevation for the backfill and downgradient OR aquifer <br /> well . <br /> The rise in HI aquifer well , G85, in 1984 through 1987 is <br /> thought to be caused by higher recharge rates and recovery from <br /> mine dewatering . The stabilization of water levels in 1988 and <br /> 1989 is thought to be caused by a decline in recharge and an <br /> offsetting recovery from mining . The rise in water level in the <br /> last four years in HI aquifer well , GF4, is thought to be caused <br /> by recovery from mining upgradient. Water levels in this portion <br /> of the aquifer could now be above pre-mine conditions due to the <br /> input of additional water just downgradient of the mining . <br /> • Each of the water levels in the three GE wells have been <br /> recovering for several years from mine dewatering from the <br /> adjacent operation . The rate of rise declined in 1988 and these <br /> wells showed some stabilizing in 1989. These affects are thought <br /> to be due to the greater time since dewatering stopped . It may <br /> also be partly attributed to lower recharge rates and/or the mine <br /> dewatering that started in the C pit in 1988. <br /> 2. 1 .2 WATER-LEVEL CHANGES <br /> The water-level changes for the period of record are <br /> presented on figures in Appendix A. Depth to water and water- <br /> level elevation are tabulated in this appendix , also. Many wells <br /> reflect changes in annual precipitation amounts. Figure 2-1 ( page <br /> • 2-17) presents precipitation at Trapper Mine. Table A-1 on page <br /> 2-3 <br />