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Spring 2017 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />Figure 5. Southward view of a subsidence crack with an orientation nearly parallel with the road and <br />similar to cracks observed on the nearby MVB E6-13 pad. <br />4.3.3 Location 4 <br />As Traverse C -C circles to the west and north, the road drops steeply approximately 800 feet south <br />of the MVB E6-14 pad. As it crosses the E -seam Longwall Panel E6 headgate entries, a noticeable <br />elevation drop was observed in association with a series of semi -parallel subsidence cracks (at <br />least five) over a distance of approximately 50 feet. The abrupt 10 -inch elevation change was <br />associated with a subsidence crack with maximum dimensions of 4 inches wide and 10 inches deep <br />(Figure 6). Portions of the crack were filled, likely from vehicle traffic. E -seam overburden <br />thickness at this location is about 700 feet. Approximately 50 feet north of the elevation offset in <br />the road was a series of three smaller semi -parallel subsidence cracks with an orientation of about <br />N60°E. Each of these cracks crossed the entire road and extended into vegetative cover on both <br />sides (Figure 7). The maximum dimension of these cracks was 4 inches wide and 16 inches deep. <br />831-032.799 Wright Water Engineers, Inc. Page 15 <br />August 2017 <br />