2013-09-27_REPORT - C1980007 (4)

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Spring 2013 Subsidence and Geologic Field Observations South of Divide and Dry Fork Mining Areas (E -Seam) of these cracks measured 45 feet in length, 2 inches in width and 10 inches in depth. Longwall mining had not yet occurred beneath this area (still more than 1,500 feet away) leading to the conclusion that these cracks represented differential settlement in the fill material placed over the culvert crossing of the small drainage. E -seam overburden depth at this location is about 780 feet. Figure 11. Southeastward view toward the MDW E4 -12 pad where the access road crosses a small drainage as observed during the spring 2013 field visit. Note the foreground cracks in the roadway even though the longwall mining face is more than 1,500 feet away. These cracks appear to be related to differential settlement of the fill over the culvert crossing at this location. 4.8 Photographic Observation Point 2 This photographic comparison location (formerly Photographic Observation Point 13) was established during the fall 2009 field visit along the traverse now known as Traverse F -F (approximately 500 feet southwest of point F). Overburden depth to the E -seam in this area is about 680 feet. This location established two views; one looking northward toward the MDW E2- 27 pad and the other looking northeastward toward the MDW E2 -30.5 pad. Comparison photos obtained during our spring 2013 field visit revealed no noticeable changes from those obtained previously even though mining had occurred beneath both MDW pads between photo dates. 831 - 032.795 Wright Water Engineers, Inc. Page 21 September 2013