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Spring 2018 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />In 2016 and again in 2017, this traverse was extended southward across what is now mined E - <br />seam Longwall Panel E6 and unmined E -seam Longwall Panel E7. This extension provides access <br />to the E6-13 and E6-14 MVB pads, as well as the MVB E7-12 pad. <br />Previously reported subsidence -related observations over E -seam Longwall Panels E2 to E5 were <br />no longer visible with the exception of the slump adjacent to the drill road above the Deer Creek <br />valley. Subsidence features previously observed during our 2017 field visits were becoming very <br />difficult to identify, especially if one was not aware that they had previously existed. As a result, <br />there are no discussion or photographs of these locations included in this report. <br />The elevation offset associated with a subsidence crack in the road leading to MVB E6-14 pad <br />(Location 3) is still present and has not been erased by regrading. However, continued vehicle <br />traffic on this road has lessened the abrupt change in the road. Other subsidence cracks observed <br />on, or near, the MVB E6-14 pad further north are becoming more obscured with time. <br />4.4 Traverse D -D' <br />This traverse originates along the south side of the Dry Fork Road (Traverse A -A • D Q G <br />southward up Poison Gulch (drainage east of Deer Creek). This traverse crosses mined portions <br />of E -seam Longwall Panels E3, E4, E5, and E6, as well as unmined portions of E -seam Longwall <br />Panel E7 (see Map 1). The E -seam overburden depth along this traverse varies from slightly less <br />than 700 feet to almost 900 feet. <br />As of our spring 2018 field visit, portions of this traverse south of Dry Fork provide access to <br />seven MVB pads above mined E -seam Longwall Panels E5, E6, and E7 (i.e., E5-15, E5-16, E6- <br />12, E7-8, E7-9, E7-10, and E7-11). Both the E5-15 and E5-16 MVB pads had been reclaimed as <br />of the spring 2018 field visit. <br />A sizeable differential settlement crack on the MVB E6-12 pad was originally observed at this <br />location during both the spring and fall 2016 field visits. Both 2016 visits pre -dated longwall <br />mining beneath the area, providing confirmation that the crack was the result of differential <br />settlement. As of our spring 2017 visit, longwall mining had passed beneath this area with the <br />consequence being a significant drop (up to 3 feet) of the outer edge of the pad coincident with the <br />831-032.900 Wright Water Engineers, Inc. Page 11 <br />August 2018 <br />