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Fall 2017 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />As Traverse D -D • F R Q W L Q X H V pasVes USES �MndKM wflerUa 66de X S <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 continuing signs of <br />weathering and healing. Subsidence cracks previously observed on the MVB E5-16 pad also <br />remain present but are difficult to delineate without prior knowledge of their existence. <br />Continuing south, Traverse D -D provides access to MVB pads for E5-15, E6-12, and E7-8, E7-9, <br />E7-10 and E7-11). No subsidence -related features were observed along the access road to MVB <br />E5-15. A sizeable differential settlement crack on the MVB E6-12 pad was originally observed at <br />this 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 />previously -observed differential settlement cracks (Location 5). Evidence of this elevation change <br />on the outer edge of the pad was still present during our fall 2017 site visit. <br />Smaller subsidence cracks were also observed in the access road approximately 800 feet south of <br />the MVB E6-12 pad as represented by elevation changes in the road that were inconsistent with <br />water bar construction. This location is above the headgate side of E -seam Longwall Panel E6 <br />with an overburden thickness of about 800 feet. This minor elevation changes in the access road <br />remained evident during our fall 2017 field visit. <br />Fall 2017 observations of the MVB pads above the unmined E -seam Longwall Panel E7 <br />represented baseline visits prior to longwall mining passing beneath these areas. <br />4.4.1 Location 5 <br />A visit to the MVB E6-12 pad during spring 2017 revealed that a large portion of the outside edge <br />of the pad had dropped up to three feet. The location of the head of the down -dropped block of <br />material was relatively coincident with the most continuous of the previously -described <br />differential settlement cracks described during both field visits in 2016. While this movement was <br />likely exacerbated by longwall mining beneath the area, there were no other subsidence cracks <br />831-032.799 Wright Water Engineers, Inc. Page 21 <br />February 2018 <br />