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direction in the HI aquifer has been changed mainly near the A pit near well GF -4. The overall flow <br />regime in this aquifer is northerly, similar to that observed in 2016 (see Hydro -Engineering, 2017). <br />Flow in the HI aquifer in the permit extension area on the east side of the Trapper Mine changes to <br />the northwest due to changes in the structure of the H and I coal seams. The addition of the GLEV-3 <br />water -level elevation shows that the ground -water flow direction in the HI aquifer changes to the <br />northwest in the northeast corner of the Trapper permit area. <br />The ground -water gradient between the backfill aquifer and the un -mined HI aquifer <br />downgradient is relatively flat as it is in the QR backfill. The contours in the HI aquifer have also <br />been changed on the east side where previous mining in the A pit has likely caused water level <br />declines near this pit. The D and K pits were used to mine the I seam and the K pit also mined the H <br />and I seams in 2010 through 2012 and the I2 seam in 2013. The H and I seams were mined in the K <br />pit in 2014 while the L pit mined the I seam in 2014 and the H and I seams in 2015 through 2017. <br />The 3rd White Sandstone aquifer water -level elevations are presented on Map No. 2-3. <br />Wells GC -2, P-8 and GP -9 were used in the development of this map. Flow direction in the 3rd <br />White Sandstone is mainly toward the north, as expected. The 2017 contours are very similar to <br />those observed from the last few years. The flow direction in the 3rd White Sandstone changes to the <br />northwest in the permit extension area on the east side of the Trapper Mine. Water -level elevation <br />contours have to shift to the northeast in the extension area because the base of the 3rd White <br />Sandstone would be above the water -level elevation if they continue to the east. The saturated <br />thickness in the 3rd White Sandstone in the northeast portion of the extension is thought to be only a <br />few tens of feet with this sandstone being dry farther south in the permit extension area. <br />Trapper Mining Company 2-11 <br />2017 Annual Report <br />