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Spring 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />mining. In general, subsidence - related tension cracks observed in previous site visits were <br />noticeably weathered and less discernible. <br />Longwall mining in the SOD mining area was initiated at the east end of E -seam Longwall Panel <br />E1 in December 2008. As of the time of our spring 2013 field visit (June 13 and 14), mining was <br />complete on E -seam Longwall Panels E1, E2 and E3 and had progressed across the eastern one - <br />third of E -seam Longwall Panel E4. Subsidence related observations at the surface were noted <br />along Traverses C -C, E -E', F -F and I -P. Subsidence related cracks observed along these traverses <br />were somewhat expected given their location above active longwall mining activities at the time <br />of the Spring 2013 visit (i.e., areas of maximum expected dynamic subsidence effects). Additional <br />details regarding the observed subsidence features can be found in Sections 4.3, 4.6, 4.7 and 4.14 <br />of this report. <br />Lastly, cracks in MDW pads were also observed throughout the SOD above areas where there has <br />yet to be any mining activities. As discussed in previous subsidence reports, evidence indicates <br />that the observed cracks are the result of differential settlement of portions of these pads where fill <br />placement is the greatest. <br />831 - 032.795 Wright Water Engineers, Inc. Page 2 <br />September 2013 <br />