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precipitation event. As with GF-5, well GF-7 (both completed in the HI backfill) continues a • <br /> gradual overall recovery. The larger storage value in the unconfined backfill aquifer may <br /> dampen the effects of dry and wet years. A small amount of recovery from the A pit <br /> mining in this area may still be occurring. The response seen at well P-8 is due to seasonal <br /> variations in recharge. <br /> Water levels for wells GF-2 and GF-4 are presented in Figure A-8. Water levels <br /> in these wells have been quite stable for a number of years with a rise in GF-4 due to <br /> spring recharge. The U aquifer lies beneath the coal horizons. Mining occurred south of <br /> well GF-4 in the early 1980's and seems to have made the water levels in this area of the <br /> HI aquifer very steady. Water levels in the upgradient unconfined backfill aquifer do not <br /> fluctuate as much as the confined HI aquifer. It is also possible that the backfill spring in <br /> Johnson Gulch may be limiting the head in the backfill aquifer. <br /> Figure A-9 presents water levels for wells GF-3 (KLM aquifer) and Coy (alluvium). <br /> The increases in water levels in well GF-3, due to increased precipitation, seem to occur <br /> later in the year showing a few months lag. Water levels at Coy have gradually increased <br /> since late 1995 due to the significant increase in precipitation over this period. The <br /> unconfined alluvial aquifer responds gradually to recharge changes. <br /> Wells GF-6 and GF-11 are completed in the QR aquifer and QR backfill, <br /> respectively. They are located downgradient of the inactive E pit. GF-11 is 1150 feet <br /> upslope and upgradient of GF-6. The rise in 1998 has been larger in well GF-11 than in <br /> GF-6 (see Figure A-10). These increases observed in both wells are probably due to <br /> higher recharge rates over the last four years. Some of the rise in the backfill could still be <br /> 2-6 <br />