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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />4.14.2 Location 9 <br />Location 9 refers to a general area rather than one specific location. This area was discussed in <br />the Fall 2012 Subsidence report as Locations 5 and 6. <br />The westernmost portion of this area is located along the drill road in the small drainage east of <br />the MDW E3 -12 pad. At this location, several cracks were observed during the fall 2012 field <br />visit including one immediately south of the drainage culvert on the cutslope and several others <br />crossing the road east of the drainage. All observed cracks were oriented in a N30 -40 °E direction <br />and typically offset from each other by about 15 -25 feet. Overburden thickness above the E -seam <br />at this location is about 700 feet. Figure 18 shows the first crack (right white arrow) east of the <br />drainage along with two other smaller subparallel cracks (white arrows to the left) as observed <br />during the fall 2012 field visit. Figure 19 is of the same general area as observed during our spring <br />2013 field visit. Note that the cut slope has failed and the road regraded leaving relatively little <br />evidence of the cracks. <br />Figure 18. <br />E3 -12 pad <br />Fall 2012 southward view of subparallel subsidence cracks located east of the MDW <br />The white arrows identify the crack locations. <br />831 - 032.795 Wright Water Engineers, Inc. Page 28 <br />September 2013 <br />