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Fall 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Figure 9. Southward view of a large subsidence crack located east of the MDW E4 -14 pad. This <br />crack was continuous over about 100 feet and had a maximum width of 24 inches and depth of <br />10.5 feet. <br />3.7.2 Location 2 <br />Location 2 is an area that includes several subsidence - related features over a distance of about 300 <br />feet in, or adjacent to, the access road to MDW E4 -11 on the north side of Dry Fork (Location 2) <br />(Map 1). On the west end of this area, three cracks with a nearly east -west orientation were noted <br />in the road. These cracks had a maximum length, width and depth of about 25 feet, 1 inch and 4 <br />inches, respectively. Figure 10 depicts one of these cracks. Cracks within in the road were well <br />worn and eroded from vehicle traffic. Crack extension beyond the road was minimal but with <br />more defined edges reflecting the relatively recent mining beneath the area. The eastern end of <br />this area (about 800 feet west of the MDW E4 -11 pad) is a sandstone outcrop adjacent to the road <br />on the north. At this location, several fresh cracks (0.5 to 0.75 inches wide) were observed in the <br />sandstone outcrop (Figure 11) along with noted expansions of pre- existing joints. The latter were <br />apparent based on staining and weathering to depth. <br />831 - 032.795 Wright Water Engineers, Inc. Page 14 <br />January 2014 <br />