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Spring 2014 Subsidence and Geologic Field Observations <br />South of Divide a d Dry Fork Mining Areas (E -Seam) <br />Observations along this traverse found that a portion of the road had slumped as a result of the <br />mining of E -seam Longwall Panel E4 beneath the area after our fall 2013 field visit. This slump <br />is discussed below as Location 7. <br />Previously observed cracking at the MOW E3 -12 pad and along the drill road to the east were <br />again visited and observed relative to obslervations observed during the fall 2012 field visit. These <br />cracks remain evident but showing considerable signs of weathering and healing. No other <br />subsidence - related features were observed on MDW pads and road above mined E -seam Longwall <br />Panel E3. <br />Of the three MDW pads located above r�ined E -seam Longwall Panel E4, only the MDW E4 -16 <br />pad showed subsidence - related featuresj. Observations associated with this pad are discussed <br />below as Location 8. <br />4.14.1 Location 7 <br />Longwall mining occurred beneath the western end of E -seam Longwall Panel E4 in early to mid - <br />April, 2014. Approximately 800 feet south of the westernmost hairpin turn, approximately 50 feet <br />of the outside portion of the roadway failed (slumped) over a vertical distance of about 20 feet in <br />a downslope direction (i.e., westward) (fee Figure 18). This slump in colluvial material is more <br />than 100 feet above the Deer Creek valley floor and approximately midway between the mined E- <br />seam Longwall Panel E4 headgate and tailgate. Remnants of this failure were observed during our <br />spring 2014 field visit even though ev�dence suggested that this portion of the road has been <br />regraded since the initial occurrence. E -lseam overburden at this location is between 450 and 500 <br />feet. It appears likely that mining- inducod subsidence exacerbated the tendency for the fill portion <br />of the roadway constructed on a steep slope to move downslope. <br />831 - 032.796 Wright Water Engineers, Inc. Page 29 <br />September 2014 <br />