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unconfined alluvial aquifer generally responds gradually to recharge changes. The 2011 and 2012 <br />water -level elevations are slightly lower 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 is tabulated in Table A -1 in Appendix A. Figure A -11 presents the water level <br />versus time plot, showing a rising trend for the previous six years during the period of above normal <br />precipitation and fairly steady water levels during the 2012 low precipitation year and the slightly <br />above normal precipitation in 2014. These responses are interpreted to be due to an increase in <br />recharge followed by a decrease in recharge. These water levels show no response to the higher <br />precipitation in 2005 while a good response in shown to the higher 2006 through 2011 precipitation. <br />This data indicates that a one year lag in the water level responses in well GP -5 to precipitation may <br />occur. These responses indicate that the mining from the QR seams, which is nearest in the F pit <br />mining that began in 1997, has not significantly affected water levels in well GP -5. <br />Figure A -11 presents the change in water -level elevation for alluvial well P -1, located in <br />the Pyeatt drainage north of the PA. This data demonstrates classic seasonal responses, highs in <br />winter /spring and lows in late summer /fall. Overall the water levels have been fairly steady in well <br />P1 in 2012 through 2014 with the variations in precipitation. Well P -3 is completed in the Lewis <br />Shale outcrop, which is in contact with the Pyeatt alluvium but has been dry for a few years. Water - <br />level elevations for the Johnson Gulch alluvial well J -1 are also presented in Figure A -11. The J -1 <br />water levels remained steady in 2012 through 2014, indicating that these variations in precipitation <br />have not affected these alluvial water levels. <br />2.2 GROUND WATER -LEVEL ELEVATION (PIEZOMETRIC MAP SUMMARY) <br />Hydro-Engineering developed three piezometric maps to show the water level flow <br />patterns for the QR, Hl and 3rd White Sandstone aquifers at Trapper Mine. Water levels from the <br />Trapper Mining Company 2 -8 <br />2014 Annual Report <br />