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Fall 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <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- 01/02/03, E4 -04 and E4 -05/06 (all above mined E -seam <br />Longwall Panel E4). Spring 2013 field observation found subsidence - related cracking on the <br />MDW pad E4- 1/2/3, on the road leading to the MDW E4 -04 pad and on the MDW E4 -04 pad <br />itself. None of these subsidence - related features were identifiable during the fall 2013 field visit. <br />This traverse is also the access point to two new MDW pads that overlie unmined E -seam Longwall <br />Panel E5. These include MDW E5 -05 (located on the easternmost arm of the traverse on the way <br />to MDW E4- 01/02/03) and E5 -06/07 (located on the westernmost arm of the traverse on the way <br />to MDW E4 -05). Visits to these pads were considered baseline and photographs were obtained to <br />record their pre- mining condition. E -seam overburden depth at these two locations is between <br />1,075 and 1,100 feet. <br />3.7 Traverse F -F' <br />This traverse originates along the south side of Dry Fork Road and travels southeastward parallel <br />to the Dry Fork for approximately 4,000 feet across mined portions of E -seam Longwall Panels <br />E3 and E4 (see Maps 1 and 2) where the overburden depth to the E -seam ranges from slightly less <br />than 700 feet to about 850 feet. <br />Subsidence features have been noted along the northern portion of this traverse dating back to the <br />spring of 2012, when E -seam Longwall Panel E3 mined beneath the area. At that time, subsidence <br />features were noted both north and south of the road parallel to Dry Fork near the turnoff to the <br />MDW E3 -29 pad. Fall 2012 observations showed some continued evidence of subsidence - related <br />cracks but with obvious softening of features from weathering. Spring and fall 2013 observations <br />found that most of this area had been regraded and evidence of these subsidence - related features <br />had been repaired and healed. <br />The southern portion of this traverse provides access to four MDW pads including E4 -11, E4 -12, <br />E4 -13 and E4 -14. Each of these pads overlie E -seam Longwall Panel E4. At the time of our fall <br />2013 field visit, each of these pads had been undermined (with active mining occurring beneath <br />the MDW E4 -14 pad). Observations on the MDW E4 -12 and MDW E4 -13 pads revealed no <br />831 - 032.795 Wright Water Engineers, Inc. Page 11 <br />January 2014 <br />