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Fall 2014 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mininq Areas <br />3.12.1 Location 2 <br />Our visit to the MDW E4 -16 pad represents the second field visit after longwall mining occurred <br />beneath the area. As previously reported, this pad is located several feet above a sandstone layer <br />as observed at depth in several subsidence cracks during our spring 2014 field visit. Photographs <br />of this pad taken during the spring and fall 2014 field visits are provided for comparison purposes <br />in Figure 8. <br />a <br />ME; <br />Figure 8. Spring 2014 northward view of the MDW E4 -16 pad showing the longest of the subparallel <br />subsidence cracks (left). A fall 2014 view of the same area finds this same crack had weathered <br />significantly, which resulted in wider but shallower dimensions (right). <br />Fall 2014 observations found that subsidence cracks with an orientation of about N5 °E were still <br />present but generally greater in width (primarily due to weathering at the edges) and shallower in <br />depth (due to sediment infill). Maximum dimensions observed during the fall 2014 field visit were <br />20 inches deep and 14 inches wide. The main crack was observed to have a discontinuous <br />measured length of approximately 300 feet. Three subparallel discontinuous cracks were noted to <br />the east of the main crack with offset distances of between 20 and 30 feet. The brittle nature of <br />831 - 032.796 Wright Water Engineers, Inc. Page 16 <br />March 2015 <br />