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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Specific subsidence - related cracking was observed on MDW pad E4 -1/2/3 (Location 4), on the <br />road leading to the MDW E44 pad (Location 5) and on the MDW E44 pad itself (Location 6). <br />Each of these observations are described below. <br />4.6.1 Location 4 <br />Several small cracks were observed on the eastern portion of the MDW E4 -1/2/3 pad (Figure 6) <br />and along the crest of the outside fill slope (Figure 7). The maximum dimensions of the pad cracks <br />were 8 feet long, 0.25 inches wide and 1 inch deep. Cracks observed along the crest of <br />uncompacted fill material comprising the containment berm on the eastern edge of the pad had <br />maximum dimensions of 20 feet in length, 0.375 inches in width and 2 inches in depth. These <br />cracks are subsidence related but exacerbated by differential settlement of the fill at the outside <br />edge of the pad. Longwall mining beneath this pad occurred approximately five months prior to <br />our spring 2013 field visit. The E -seam overburden depth at this location is approximately 1,100 <br />feet. <br />831 - 032.795 Wright Water Engineers, Inc. Page 16 <br />September 2013 <br />