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mining has been replaced by recharge to the HI aquifer. The overall gradual declines in water levels <br />in well GP -3 in the years just prior to 2005 are probably a function of below normal precipitation <br />during this period. The water level in well GP -4 has also recovered to pre -mine levels but observed <br />variable levels in 2004 through 2016. The decline in the fourth quarter is similar to other large <br />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 />steady in 2001 and stayed fairly steady for the next six years with a small increase in 2006 through <br />2011. A very gradual decline was observed in 2012 through 2016. <br />Figure A-10 also presents water levels for the well COY (alluvium). Water levels at the <br />COY well started to decline in 2009 after seven years of overall rising. Overall this gradual decline <br />has continued through 2016 but levels are still higher than they were in the 1990s. The unconfined <br />alluvial aquifer generally responds gradual to recharge changes. The 2008 and 2009 water -level <br />elevations were larger than the natural high water levels in 1985 and 1986. Water levels in flowing <br />well GP -4 average slightly less the last few years then they had in the previous decade. <br />Well GP -5 is completed in the QR aquifer. GP -5 is immediately downgradient of A pit. <br />Water -level data from 2007-2016 is tabulated in Table A-1 in Appendix A (see attached CD for all <br />historical water -level data). Figure A-11 presents the water level versus time plot, showing a rising <br />trend for the previous six years during the period of above normal precipitation and fairly steady <br />water levels during the 2012 low precipitation year and a small decline in 2014 through 2016 with <br />the slightly above normal precipitation to slightly below normal precipitation. These responses are <br />interpreted to be due to an increase in recharge followed by a decrease in recharge. These water <br />levels show no response to the higher precipitation in 2005 while a good response in shown to the <br />higher 2006 through 2011 precipitation. This data indicates that a one year lag in the water level <br />Trapper Mining Company 2-8 <br />2016 Annual Report <br />