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Spring 2014 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Panel E4 MDW pads is between 1,050 and 1,150 feet. Specific subsidence - related cracking <br />observed during the spring 2013 field visit included locations on the MDW E4 -1/2/3 pad, on the <br />road leading to the MDW E44 pad and On the MDW E44 pad itself. Cracks associated with the <br />MDW E44 road and pad were sufficiently healed so as to be undetected. Cracks were again <br />observed on the MDW E4 -1/2/3 pad are discussed below as Location 2. <br />No subsidence - related cracking were observed on MDW pads above unmined E -seam Longwall <br />Panel E5 as mining had not yet occurre4 beneath them. Of note was a material stockpile slope <br />failure to the east of the MDW E5 -5 pad (Location 3). <br />4.6.1 Location 2 <br />Several small cracks were observed during the spring 2013 field visit on the eastern portion of the <br />MDW E4 -1/2/3 pad and along the crest 6f the outside fill slope (i.e., the area of the pad with the <br />greatest vertical fill depth). Similar cracks were observed during the spring 2014 field visit. The <br />maximum dimensions of the pad cracks observed in 2014 were 2 inches wide and 27 inches deep. <br />One relatively continuous crack was observed over a distance of about 120 feet in a N10 °W <br />orientation. This crack could not be traded off the pad in either direction, and therefore, may be <br />cause primarily by differential settlement (see Figure 5). <br />Figure 5. Spring 2014 image looking south /sout east at several small differential settlement cracks exacerbated by <br />subsidence along the eastern portion of the E4-11P/3 MDW pad (the pad area with the greatest vertical fill depth). <br />831 - 032.795 Wright Water Engineers, Inc. Page 15 <br />September 2014 <br />