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Spring 2017 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />overburden depths along this traverse vary from 450 feet in the Deer Creek drainage to <br />approximately 900 feet over mined E -seam Longwall Panels E4 and E5. <br />Photographs from east- and west -facing overview locations were obtained from designated <br />locations along this traverse as in previous visits. Photographic comparisons to previous images <br />found no substantive differences. <br />Numerous MVB pads have been historically accessible from this traverse including E3-6, E3-12, <br />E3-17.5, E3-21, E3-25, E4-15, E4-16, E4-17, and E4-18 over mined E -seam Longwall Panels E3 <br />and E4. As of our 2016 field visits, each of the previously mentioned MVB pads had been <br />reclaimed except E4-18. <br />As of the fall 2016 field visit, this traverse also extends southward across mined portions of E - <br />seam Longwall Panel E6 and unmined E -seam Longwall Panel E7. This extension leaves the <br />previous traverse near the E5-17 MVB pad heading southward to provide access to the E6-13 and <br />E6-14 MVB pads. Both of these pads were observed as baseline visits during our fall 2016 field <br />visit, during which we observed that both sites are constructed with little fill material and therefore <br />showed no signs of differential settlement. <br />Previously reported observations along this traverse included a small subsidence crack in the cut <br />slope at the beginning of this traverse, a slump on the downslope side of the drill road above the <br />Deer Creek valley, subsidence cracks on the E4-16 MVB pad, and cracks in the road near, and on, <br />the E5-17 MVB pad. Due to reclamation of the E4-16 pad, there is no further evidence of <br />subsidence cracking at this location. Observations during our spring 2017 field visit found the <br />small crack in the cut slope at the beginning of the traverse, and the cracks previously observed in <br />the road near, and on, the E5-17 MVB pad, were no longer visible. The only previously -reported <br />feature that remained visible was the slump adjacent to the drill road above the Deer Creek valley. <br />Subsidence related features were observed, however, at several locations over E -seam Longwall <br />Panel E6 during our spring 2017 field visit. Longwall mining had passed beneath this area between <br />our last two field visits. Several subsidence cracks were observed along the road leading to, and <br />on, the MVB E6-13 pad (Location 2). Subsidence cracks were also observed on the main road <br />south/southeast of the MVB E6-13 pad (Location 3). A significant elevation offset in conjunction <br />831-032.799 Wright Water Engineers, Inc. Page 12 <br />August 2017 <br />