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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. Overall steady water levels were observed in 2012 through 2019. <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 with a small rise in 2017 and an overall gradual decline in 2018 and <br /> 2019 but levels are still higher than they were in the 1990s. The unconfined alluvial aquifer <br /> generally responds gradual to recharge changes. The 2008 and 2009 water-level elevations were <br /> larger than the natural high water levels in 1985 and 1986. <br /> Well GP-5 is completed in the QR aquifer. GP-5 is immediately downgradient of A pit. <br /> Water-level data from 2010-2019 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. A very gradual rise <br /> was observed in 2017 through 2019. These responses are interpreted to be due to an increase in <br /> recharge followed by a decrease in recharge with slightly larger recharge in 2017, slightly less <br /> recharge in 2018 and more in 2019. These water levels show no response to the higher precipitation <br /> in 2005 while a good response in shown to the higher 2006 through 2011 precipitation. This data <br /> indicates that a lag of one year in the water level responses in well GP-5 to precipitation may occur. <br /> These responses indicate that the mining from the QR seams, which is nearest in the F pit mining <br /> that began in 1997,has not significantly affected water levels in well GP-5. <br /> Trapper Mining Company 2-8 <br /> 2019 Annual Report <br />