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Fall 2016 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />Photographs from east- and west -facing overview locations were obtained as in previous visits. <br />Photographic comparisons to previous images found no substantive differences. <br />4.4 Traverse D -D' <br />This traverse originates along the south side of the Dry Fork Road (Traverse A -A') and proceeds <br />southward up Poison Gulch (drainage east of Deer Creek). This traverse crosses mined portions <br />of E -seam Longwall Panels E3, E4, and E5, as well as unmined portions of E -seam Longwall <br />Panels E6 and E7 (see Map 1). The E -seam overburden depth along this traverse varies from <br />slightly less than 700 feet to almost 900 feet. <br />The portion of this traverse south of Dry Fork currently provides access to three MVB pads above <br />E -seam Longwall Panels E5 and E6 (i.e., E5-15, E5-16, and E6-12). At the time of our fall 2016 <br />field visit, longwall mining had occurred beneath E5-15 and E5-16 but had not yet reached E6-12 <br />(see Map 1). <br />As Traverse D -D' continues southward up Poison Gulch, it passes USFS pond P95 where a side <br />access road leads west and then north to the large MVB E5-16 pad. A previously observed slump <br />on the cut slope side of the road leading to this pad remains evident but shows signs of weathering <br />and healing. Subsidence cracks noted on the MVB E5-16 pad also remain present but are <br />increasingly difficult to identify. <br />Continuing south, Traverse D -D' provides access to the MVB E5-15 and E6-12 pads. No <br />subsidence -related features were observed along the access road to, or on, these pads. As first <br />observed during our spring 2016 field visit, a sizeable crack, with orientation N5°W, was apparent <br />on the west edge of the MVB E6-12 pad. This crack is above the unmined portion of E -seam <br />Longwall Panel E6 where the greatest fill material has been placed. This nearly continuous crack <br />was again observed during our fall 2016 field visit. With the longwall mining face more than <br />1,500 feet to the east, this feature is assuredly associated with differential settlement of the fill <br />materials. <br />831-032.798 Wright Water Engineers, Inc. Page 14 <br />January 2017 <br />