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Fall 2012 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />This traverse is generally flat and stable on soil and colluvium derived from the Wasatch <br />Formation mixed with intrusive rocks of the West Elk Mountains and from overlying bedrock <br />units of the Barren Member of the Mesaverde Formation. Numerous MDW drill pads are <br />accessible from this traverse including El -15, E1 -19, E1 -26.5, E1 -30.5, E1 -34, E1 -38, E2 -38, <br />E1 -42, E2 -42, E2 -44.5. E1 -45, and E2 -47.5. These MDW pads are located above mined E -seam <br />Longwall Panels El and E2. At the time of our fall 2012 field visit, a portion of this traverse <br />was impassable due to re- grading of the road east of the MDW -E1 -26.5 pad and a very heavy <br />rainfall. As a result, three of the MDW drill pads (E1-15, E1-19 [reclaimed], and E1-26.5) were <br />not visited during our October 2012 field visit. No changes from previous observations were <br />noted along this traverse. <br />3.4 Traverse K -K' <br />This Dry Fork Road traverse extends east - southeastward from Monument Dam (Minnesota <br />Reservoir) approximately 4 miles to the point where the road crosses Deep Creek (see Maps 2 <br />and 4). Portions of this traverse are above mined E -seam Longwall Panels El, E2 and E3 as well <br />as unmined portions of Longwall Panels E4, E5 and E6. Overburden depth to the E -seam along <br />this traverse ranges from 150 feet on the west end adjacent to Minnesota Reservoir (west of the <br />planned E -seam mining area) to 1,200 feet. The area of this traverse in the immediate vicinity of <br />Minnesota Reservoir is outside the proposed E -seam mining influences (see Appendix B of the <br />Spring 2011 Report for angle of draw calculations). Soil, alluvium, and colluvium derived <br />primarily from the Wasatch Formation can be observed along this traverse with thicknesses <br />estimated to be from a few tens of feet to 150 feet or more. <br />Photographic Observation Point 12 is located on the Dry Fork Road near the Horse Gulch Road <br />intersection. Photographs taken at this location show no change from the photographs obtained <br />during the spring 2012 field visit. <br />In addition, seven shorter traverses originate from Traverse K -K' (i.e., Kl -K1', K2 -K2', K3 -K3', <br />K4 -K4', K5 -K5'. K6 -K6' and K7 -K7'). Each of these traverses was visited during the fall 2012 <br />field visit (Map 2). <br />831 - 032.794 <br />April 2013 <br />Wright Water Engineers, Inc. Page 7 <br />