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be due to drilling for deeper coal in this area. Backfill well GD-3 is approximately 1200 feet <br />uPgradient of well GD-2. It is topographically higher and closer to D Pit. Water-level changes in <br />well GD-3 have been more gradual than changes in well GD-2. The unconfined backfill aquifer's <br />storage parameter would be much larger than the storage coefficient for the confined aquifer at GD- <br />2 and, therefore, would be expected to dampen responses. <br />Water levels in well GP-9 gradually increased in 2008 showing better recharge for the <br />last few years. This water-level change is likely natural except for the fourth quarter drop in 2007 <br />which seems to be an outlier. <br />Figure A4 presents water levels for wells GF-7 and P-8. These wells are completed in <br />the HI backfill and 3rd White Sandstone aquifers, respectively. Water levels in well GF-5 (see <br />Figure A-1) and GF-7 (see Figure A-6) were slightly higher in 2008 (both completed in the in <br />backfill). The larger storage value in the unconfined backfill aquifer may dampen the effects of dry <br />and wet years. The recovery from the A pit mining in this area may be complete. Overall the water <br />levels in well P-8 were higher in 2008. <br />Water levels for well GF4 are presented in Figure A-5. A large rise in water level in <br />well GF-4 was observed in the last half of 1999 after the repair of the casing on September 29, <br />1999. Water levels overall were fairly similar in 2008 to those observed in 2007 in well GF-4. <br />Mining occurred south of well GF-4 in the early 1980's and is expected to limit water-level changes <br />in the HI aquifer near well GF-4. 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 Johnson <br />Gulch may be limiting the head in the backfill aquifer. <br />Wells GF-6 and GF-11 are completed in the QR aquifer and QR backfill, respectively. <br />Backfill well GF-11 is located on the downgradient side of the inactive E pit, while well GF-6 is <br />located downgradient of the pit. GF-11 is 1150 feet upslope and upgradient of GF-6. Overall <br />increases in water levels were observed in wells GF-6 and GF-11 for 2008 (see Figure A-6). The <br />Trapper Mining Company 2-5 <br />2008 Annual Report