Laserfiche WebLink
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. Miming has only affected the QR <br />aquifer close to the D, E, F, G, K, L and Z pits by causing drawdowns very near the pit edges. The <br />installation of backfill wells GD -3 and -GF -11 has defined the depressed elevations in the backfill <br />areas. The wells in this area experienced some fluctuating water levels during 2013. The water level <br />changes in 2013 are likely due to seasonal recharge in recent years. The backfill water levels will <br />likely stabilize lower than the pre-mine levels due to the increased permeability of the backfill <br />aquifer, which allows the water in the aquifer to be transmitted at a lower gradient. The gradient <br />calculated for the backfill near D pit is less than 0.05 ft/ft, compared to the undisturbed gradient of <br />0. 12 ffi/ft.. The- heads in the. northern end -of the backfill aquifer will likely recover above the pre -mine <br />level. Backfill springs are not expected to develop near the northern-end of-the QR backfill because <br />backfill water levels would have to -recover greater than a few tens of feet reach the lower land <br />surface elevations. Table 2 -1- of the 1990 Annual Hydrologic Report (Hydro- Engineering, 1991) <br />presents aquifer properties -at Trapper Mine. The permeabilities from the backfill l aquifers are <br />significantly greater than the coal aquifers that they replace. <br />The water-level- contours extend through the, pit areas for the F, G and Z pits because the R <br />seam was not mined in these pits-and-therefore-the QR aquifer still exist under these pit floors. Some - <br />drawdown would be expected in these areas of the QR aquifer and are indicated by the contours. <br />The QR-water-level map at Trapper- Mine was very similar- in 2013 to the 2012 water -level <br />elevations. Gradients and flow directions for the QR aquifer in 2013 are similar to those observed in <br />2012. <br />Map No. 2 -2 presents the water -level elevation contours for the HI aquifer in the fall of <br />2013. Wells GC -1, GF-4, GP -3, GP -7, and GMP -i, which are completed in the M aquifer, and <br />Trapper Mining Company 2-9 <br />2013 Annual Report <br />