2008-03-14_REPORT - C1981010 (5)

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presents aquifer properties at Trapper Mine. The permeabilities from the backfill aquifers are si 'ficantly greater than the coal aquifers that they replace. The water-level contours extend through the pit areas for the F, G and Z pits because the R seam was not mined. in these pits and therefore the QR aquifer still exist under these pit floors. Some drawdown would be expected in these areas of the QR aquifer and are indicated by the contours. The QR water-level map at Trapper Mine was very similar in 2007 to the 2006 water- level elevations. Gradients and flow directions for the QR aquifer in 2007 are similar to those observed in 2005. Map No. 2-2 presents the water-level elevation contours for the HI aquifer in the Fall of 2007. Wells GC-1, GF-4, GP-3, GP-7, and GMP-1, which are completed in the HI aquifer, and backfill wells GF-5 and GF-7, were used in the development of this map. Wells GF-~ and GF-7 are completed in the backfill in the area where the H and I coal seams were mined. Flow direction in the HI aquifer has been changed mainly near the A pit near well GF-4. The overall flow regime in this aquifer is northerly, similar to that observed in 2006 (see Hydro-Engineering, 2007). The ground water gradient between the backfill aquifer and the un-mined HI aquifer downgradient is relatively flat as it is in the QR backfill. The contours in the HI aquifer have also been changed on the east side where the A pit dewatering in 2007 likely has caused water level declines near this pit. The F and Z pits were used to mine the I seam in 2007 while the H seam was mined in the A and G pits. The 3rd White Sandstone aquifer water-level elevations are presented on Map No. 2-3. Wells GC-2, P-8 and GP-9 were used in the development of this map. Flow direction in the 3rd White Sandstone is mainly toward the north, as expected. The 2007 contours are very similar to those observed from the last few years. __ Trapper Mining Company 2-9 2007 Annual Report