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Fall 2014 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas <br />MDW E5 -20 and its access road are located on the west side of the Deer Creek drainage near the <br />intersection with Traverse I -I'. Baseline observations at this pad found no evidence of differential <br />settlement or any other mining- related effects related to the mining of E -seam Longwall Panel E4. <br />3.12 Traverse I -P <br />Traverse I -I (formerly Traverse P -P') originates in the Deer Creek drainage adjacent to the lower <br />stock pond (P74) and proceeds eastward, trending considerably north and then south, over mined <br />E -seam Longwall Panels E2, E3, and E4 and unmined E -seam Longwall Panel E5 (see Map 1). <br />E -seam overburden depths along this traverse vary from a low of 450 feet in the Deer Creek <br />drainage to more than 900 feet over E -seam Longwall Panel E5. <br />Numerous MDW pads are accessible from this traverse including E3 -6, E3 -12, E3 -17.5, E3 -21, <br />E3 -25, E4 -15, E4 -16, E4 -17, and E4 -18 over mined E -seam Longwall Panels E3 and E4. Each of <br />the pads were visited during the fall 2014 field activities. With the exception of the MDW E4 -16 <br />pad (Location 2), no subsidence - related features were observed and no apparent changes were <br />noted since our last visit. <br />Previous reported observations (fall 2013) along this traverse included a small slump on the <br />downslope side of the MDW pad access road. This slope failure was likely triggered as a result of <br />the mining of E -seam Longwall Panel E4 beneath the area sometime after our fall 2013 field visit. <br />This feature is approximately 800 feet south of the westernmost hairpin turn. This slump occurs <br />in colluvial material and is more than 100 feet above the Deer Creek valley floor and approximately <br />midway between the mined E -seam Longwall Panel E4 headgate and tailgate. Downslope <br />remnants of this failure were evident during our fall 2014 field visit, even though this portion of <br />the road has been regraded since the initial occurrence. E -seam overburden at this location is <br />between 450 and 500 feet. <br />The southernmost portion of this traverse is over unmined E -seam Longwall Panel E5. Baseline <br />visits to two new MDW pads (E5 -17 and E5 -18) during the fall 2014 field visit found no evidence <br />of differential settlement or other mining - related effects. <br />831 - 032.796 Wright Water Engineers, Inc. Page 15 <br />March 2015 <br />