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precipitation and fairly steady water levels during the 2012 low precipitation year. These responses <br />are 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 />responses in well GP -5 to precipitation may occur. These responses indicate that the mining from <br />the QR seams, which is nearest in the F pit mining that began in 1997, has not significantly affected <br />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 declined in 2012 due to less <br />precipitation. Well P -3 is completed in the Lewis Shale outcrop, which is in contact with the Pyeatt <br />alluvium. It had demonstrated the same seasonal variations (Figure A -11) as the alluvial P -1 well but <br />has been dry for a few years. Water -level elevations for the Johnson Gulch alluvial well J -1 are also <br />presented in Figure A -11. The J -1 water levels remained steady in 2012, indicating that one year of <br />below precipitation does not affect 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, HI and 3rd White Sandstone aquifers at Trapper Mine. Water levels from the <br />fall of 2012 were used to develop these maps. <br />Map No. 2 -1 presents the water -level elevations for the QR aquifer. The water -level <br />elevation is presented for the QR wells: GD -2, GF -6 and GP -5 and backfill wells GD -3 and GF -11. <br />The ground -water flow in the QR aquifer is mainly to the north. Mining has only affected the QR <br />aquifer close to the D, E, F, G, K and Z pits by causing drawdowns very near the pit edges. The <br />Trapper Mining Company 2 -8 <br />2012 Annual Report <br />