2016-04-19_REPORT - C1980007 (6)

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Fall 2015 Subsidence and Geologic Field Observations South of Divide and Dry Fork Mininq Areas occurred beneath this area, suggesting that it is the result of mass -gravity movement of the unconsolidated material placed against the cut slope on the south side of the pad. This feature is located about midway between the headgate and tailgate entries of E -seam Longwall Panel E5 where there is about 1,100 feet of E -seam overburden. The fall 2015 visit to the MVB E5-8 pad found a previously reported crack on the pad to be no longer evident and the shallow slope failure on the cut slope above the pad to be somewhat expanded due to weathering. These features were first reported in association with our spring 2015 field visit. A short discussion about this location and the comparison between spring and fall 2015 observations are provided below as Location 7. In addition, observations were made during our fall 2015 field visit at a previously reported subsidence crack location near the hairpin curve between MVB E5-12/13 and E5-14. This crack had previously manifested itself as an elevation change in the road with a down -drop to the north. Additional details about these observations are provided below as Location 8. 3.15.1 Location 7 During the spring 2015 field visit, a small crack was observed near the outside edge of the MVB E5-8 pad and near the location designated for runoff discharge from the pad (see Figure 12). The location of this crack suggested it as the likely result of differential settlement rather than subsidence. Also noted on this pad was a shallow slump on the cut slope side of the pad (see Figure 12) that appeared to have occurred likely in response to a precipitation event. 831-032.797 Wright Water Engineers, Inc. Page 19 March 2016