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Spring 2017 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />During the fall 2016 field visit, a subsidence crack was observed in the cut slope along the access <br />road near the MVB E6-8/9 pad. Observations during the spring 2017 field visit found little <br />remaining evidence of this crack. <br />Subsidence features were observed at several locations along this traverse between MVB E6-10 <br />and MVB E6-11 as longwall mining had passed beneath this area between our fall 2016 and spring <br />2017 field visits. These included a slope failure above the road and pad at MVB E6-10 (Location <br />7), a subsidence crack across the road approximately 1,000 feet east of the MVB E6-11 pad <br />(Location 8), a small cut bank slump and subsidence cracks approximately 60 feet east of the MVB <br />E6-11 pad (Location 9), and a subsidence crack on the MVB E6-11 pad itself (Location 10) <br />4.5.1 Location 7 <br />The access road west over E -seam Longwall Panel E6 passes on the south side of the MVB E6-10 <br />pad. Observations during our spring 2017 field visit found a large slope failure on the cut slope <br />(i.e., south) side of the access road as it crosses the MVB pad. This slope failure includes a portion <br />of soil and vegetation that is rafting on top of the failure surface (Figure 11). The E -seam <br />overburden thickness at this location is approximately 1,200 feet. No subsidence cracks were <br />observed on the pad or road. Differential settlement cracks had been observed on the pad <br />previously and were again observed but with no apparent exacerbation from the longwall mining <br />that had passed beneath the area between the fall 2016 and spring 2017 field visits. <br />4.5.2 Location 8 <br />During our spring 2017 field visit, a relatively long (approximately 40 feet) and semi -continuous <br />subsidence crack was observed crossing the access road approximately 1,000 feet east of the MVB <br />E6-11 pad (Figure 12). This crack is located above the intersection of the E -seam Longwall Panel <br />E6 and its headgate entries with an orientation of N85°W. The crack was observed to disappear <br />about 10 feet off the road on the cut slope side and into the vegetation on the downslope side <br />(Figures 13 and 14). The maximum dimension of the crack was 4 inches wide and 18 inches deep. <br />E -Seam overburden thickness at this location is about 1,200 feet. <br />831-032.799 Wright Water Engineers, Inc. Page 21 <br />August 2017 <br />