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Spring 2018 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />little remaining evidence of this crack. This lack of observed evidence of the crack was again <br />confirmed during the spring 2018 field visit. <br />Subsidence features had previously been observed at several locations along this traverse between <br />MVB E6-10 and MVB E6-11 as longwall mining had passed beneath this area between the fall of <br />2016 and spring of 2017. These features included a slope failure above the road and pad at MVB <br />E6-10, a subsidence crack across the road approximately 1,000 feet east of the MVB E6-11 pad, a <br />small cut bank slump and subsidence cracks approximately 60 feet east of the MVB E6-11 pad, <br />and a subsidence crack on the MVB E6-11 pad itself. Observations reported from the fall 2017 <br />field visit found that most of these features had diminished and healed considerably. Continued <br />evidence of this healing was observed during our spring 2018 field visit. <br />Spring 2018 visits to the MVB E7-5 through E7-7 pads found no subsidence features except for a <br />hillside failure above the soil storage area southwest of the E7-7 MVB pad (Location 4). <br />4.5.1 Location 4 <br />During the spring 2018 field visit to the E7-7 MVB pad, a portion of the hillside south of the <br />associated soil stockpile was observed to have failed in an easterly direction (see Figure 7). This <br />site is within 200 feet of the tailgate entries for E -seam Longwall Panel E7. The E -seam <br />overburden thickness at this location is approximately 1,100 feet. No other subsidence features <br />were observed on the pad or road. <br />4.6 Traverse F -F' <br />Traverse F -F departs Traverse E -E in a southeasterly direction over the east end of mined E -seam <br />Longwall Panels E5, E6, and E7. This traverse allows access to MVB E5-8 above mined E -seam <br />Longwall Panel E5, MVBs E6-1/2/3 through E6-7 above mined E -seam Longwall Panel E6, and <br />to MVBs E7-1/2, E7-3, and E74 over mined E -seam Longwall Panel E7 (See Map 1). The E - <br />seam overburden depth along this traverse is from 1,000 feet to more than 1,200 feet. <br />No obvious subsidence -related features were observed during our spring 2018 field visit. Some <br />parallel differential settlement cracks were noted on the north side of the E7-3 MVB pad. These <br />cracks (over the largest fill portion of the pad) were generally spaced about six feet apart and ran <br />831-032.900 Wright Water Engineers, Inc. Page 18 <br />August 2018 <br />