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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Materials observed along this traverse include soil and colluvium derived from the Wasatch <br />Formation and from intrusive rocks of the West Elk Mountains that overlay consolidated bedrock <br />units of the Barren Member of the Mesaverde Formation as exposed in sandstone outcrops and <br />along roadcuts. This traverse is moderately steep where it climbs from the Deep Creek valley floor <br />to the MDW E3 -68 and E3 -72 pad. From this location, the traverse turns east and is generally flat. <br />Overburden depth to the E -seam along this traverse ranges from 1,000 to <br />1,200 feet. <br />No subsidence features were noted along this traverse during the spring 2013 field visit. Mining <br />of the eastern end of E -seam Longwall Panel E3 occurred prior to our fall 2011 field visit. <br />4.6 Traverse E -E' <br />This traverse originates along the north side of Dry Fork Road and continues northward across the <br />eastern unmined portions of E -seam Longwall Panel E5 and mined E -seam Longwall Panels E3 <br />and E4. This traverse terminates at an MDW pad containing E3 -64/65 above mined E -seam <br />Longwall Panel E3. Note that the E3 -64/65 designation indicates one pad containing two different <br />drill hole terminating points within the mine workings). <br />This traverse contains several side tracks to other MDW pads including E3 -59/63 (above mined <br />E -seam Longwall Panel E3) and E4- 1/2/3, E44 and E4 -5/6 (all above mined E -seam Longwall <br />Panel E4). No subsidence - related features were observed along that portion of the traverse above <br />mined E -seam Longwall Panel E3 in that mining beneath this area occurred in late 2011. Previous <br />evidence of subsidence features and differential settlement were unrecognizable. The E -seam <br />overburden depth beneath these mined Longwall Panel E3 MDW pads is about 1,000 feet. <br />Subsidence - related cracking was noted along portions of the access roads and MDW pads above <br />E -seam Longwall Panel E4 in that mining beneath this portion of the traverse occurred <br />approximately four to five months prior to our spring 2013 field visit. E -seam overburden depth <br />beneath these recently mined Longwall Panel E4 MDW pads is between 1,050 and 1,150 feet. <br />831 - 032.795 Wright Water Engineers, Inc. Page 15 <br />September 2013 <br />