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Fall 2013 Subsidence and Geologic Field Observations <br />South of Divide and Dry Fork Mining Areas (E -Seam) <br />2.0 SUMMARY OF FALL 2013 FIELD STUDIES <br />On October 7 and 8, 2013, WWE performed subsidence and geologic field investigations of South <br />of Divide (SOD) and Dry Fork mining areas for MCC. Similar observations have been made <br />annually in the active or recently completed mining areas since 1996 and semi - annually since 2007 <br />as a means to assess potential longwall mining effects on the environment. This visit occurred <br />approximately three days following a weather front that moved through the area dropping about <br />0.2 inches of precipitation in the form of rain and snow. Many of the methane drainage well <br />(MDW) pads were observed to be impounding water and performing as designed to prevent runoff <br />from the pad. <br />Based on these field observations, the overall effects of longwall mining have been less than were <br />initially projected. Eighteen years of experience (1996 to 2013 inclusive) indicate that subsidence <br />features (cracks and bulges) are most visible on roads and trails, where the ground is more compact <br />and free of vegetation. These areas (or traverses) were therefore selected for specific observations <br />either on foot or using a 4 -wheel drive vehicle to efficiently obtain observable subsidence <br />information. In addition, photographic comparisons are routinely made to evaluate and document <br />changes between observations (using 13 regularly visited photographic observation points) and to <br />record their condition for future reference (Maps 1 and 2). <br />Subsidence - related tension cracks were observed during our fall 2013 field visit to the SOD and <br />Dry Fork mining areas along some drill roads accessed by U.S. Forest Service Road 711 (Dry Fork <br />Road) and on methane drainage well (MDW) pads, particularly where they exist above active <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 and Dry Fork mining areas were initiated at the east end of E -seam <br />Longwall Panel El in December 2008. At the time of our fall 2013 field visit (October 7 and 8), <br />mining was complete on E -seam Longwall Panels E1, E2 and E3 and had progressed through half <br />of E -seam Longwall Panel E4. Subsidence related features were observed at the surface along <br />Traverses C -C', E -E', F -F' and I -I'. Subsidence related cracks observed along these traverses were <br />expected given their location above relatively recent longwall mining activities (i.e., areas of <br />831 - 032.795 Wright Water Engineers, Inc. Page 3 <br />January 2014 <br />