2014-03-18_REPORT - C1981010 (5)

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backfill wells GF 5- and GF-7, were used in the development of this map. Wells GF-5 and GP 7 are - completed in the- backfill in the area where -the Hand I coal seams were mined. Flow direction in the HI aquifer has been changed mainly near -tire A pit near-well GF-4. The overall-flow regime in this aquifer is northerly, similar to that observed in 2012 (see Hydro - Engineering, 2013). Flow in the HI aquifer in the proposed permit extension area on the east side of the Trapper Mine changes to the northwest due to changes in the structure of the H and I coal seams. 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 previous mining in the A pit has likely caused water level'declines near this pit. The D and K pits were used to mine the I seam and the K pit also mined the H and I seams in 2010 through 2012 and the 12 seam in 2013. The H seam was not mined in 2009. The 3'd 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 2013 contours- are very similar to- those observed from the last few years. The flow direction in the 3' White Sandstone changes toAhe northwest in the permit extension area on the east side of the Trapper Mine. Water -level elevation contours have to shift to- the- northeast in the- extension area- because- the- base- of the. 3.'d White Sandstone -would be above the water -level elevation if they continue to the east. The saturated thickness in the 3'd White Sandstone in the northeast portion of the extension is thought to-be-only a- -few tens of feet with this sandstone being dry farther south in the permit extension area. Trapper Mining Company 2 -10 2013 Annual Report