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head in well GF-11 is greater than 20 feet above the head in well GF-6. The water levels in the <br />backfill aquifer may be near the fully recovered level from mining. <br />Figure A-7 presents water levels for GP-7 and GP-8, which are located very near the <br />eastern boundary of the PA. They are completed in the KLM and HI aquifers and may provide <br />undisturbed baseline data for these intervals but could be influenced by mining for the last few <br />years. Water levels in well GP-7 overall were steady in 2008 after a decline in 2006. Steady water <br />levels were also observed in well GP-8 after an increase was observed in this well in 2006 which <br />followed five years of declining water levels. Both of these wells are thought to be showing natural <br />responses but could be influenced by the mining that is greater than 1900 feet away. The larger <br />decline in well GP-8 indicates mining may be causing some of this decline. <br />Well GP-2 (Figure A-8) is located in a previously undisturbed area near the eastern <br />boundary of the PA. Water levels rose in 2008 in well GP-2 above the overall level of the last few <br />years. A large decline in water levels started in 1999. 0 <br />Wells GP-3 and GP4 are less than 1000 feet downgradient from A pit. Both are flowing <br />wells completed in the HI and KLM aquifers, respectively. Water levels in these two wells had <br />shown similar responses in water levels due to changes in precipitation but the 2005 through 2008 <br />water level changes were different (see Figures A-9 and A-10). Water levels in well GP-3 have <br />recovered to above pre-mine levels in this area and show that any depletion of water from <br />upgradient mining has been replaced by recharge to the M aquifer. The overall gradual declines in <br />water levels in well GP-3 in the years just prior to 2005 are probably a function of below normal <br />precipitation during this period. The water level in well GP4 has also recovered to pre-mine levels <br />but observed variable levels in 2005 through 2008. The large decline in the fourth quarter is similar <br />to other large declines observed in this well. <br />Well GMP-1 (Figure A-9) is completed in the HI aquifer to monitor ground-water <br />conditions downgradient of the ash disposal site immediately south in A pit. Water levels became <br />Trapper Mining Company 2-6 <br />2008 Annual Report