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Fall 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />Figure 8a. Fall 2013 southward view of two subsidence cracks in the road leading to the MDW <br />E4 -14 pad both from a distance. Figure 8b. Close -up of the crack located in front of the vehicle in <br />Figure 8a. <br />One of the hillside cracks was up to 24 inches wide and 10.5 feet deep (Figure 9). This crack was <br />noted to follow contour (i.e., stay along the same elevation) continuously for a distance of about <br />100 feet and discontinuously for at least three times that distance. <br />The location of cracks in this area places them above the right half of longwall panel E -4 (the <br />tailgate entry side). At the time of our visit, the active longwall face was approximately 150 feet <br />west under the MDW E4 -14 pad. Overburden depth to the E -seam in this area is about 790 feet. <br />It is unclear what subsurface features allowed this number, extent and magnitude of cracking to <br />develop at this location. It is suspected that there may be a brittle sandstone layer at a relatively <br />shallow depth in the area, but no proximal sandstone outcrops were apparent and crack inspection <br />found no such evidence. It is anticipated that these cracks will be dramatically reduced during the <br />spring 2014 field visit as the dynamic process of subsidence will have transitioned into a new post - <br />mining equilibrium. <br />831 - 032.795 Wright Water Engineers, Inc. Page 13 <br />January 2014 <br />