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Fall 2010 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />• Photographs taken at Photographic Observation Points 1, 2 and 3 were compared to images <br />obtained from these locations in previous visits. These photographic comparisons found there to <br />be no observable changes. As such, these images are not reproduced herein. <br />3.2 Traverse I-I' <br />Traverse I-I' begins at point D (of Traverse D-D') above the southern edge of mined B-seam <br />Longwall Panel 14 and continues southward across the central portion of mined B-seam <br />Longwall Panels 14 to 17 and across the east end of mined E-seam Longwall Panels E1 and <br />unmined E2 and E3 to a connection with the Dry Fork of Minnesota Creek (Dry Fork) road near <br />the eastern edge of Section 34, T13S, R90W of the 6th P.M. (see Maps 1 and 2). MDW pads <br />located (and visited) along this traverse include E1-52/53, E1-48, E2-51/52/54, E3-51 and E3-55 <br />(Map 2). This fall 2010 field visit was the first to the MDW pads above unmined E-seam <br />Longwall Panel E3. Baseline photographs were obtained at these locations for later comparative <br />purposes. <br />• Cracks were observed on the MDW E1-48 pad (Location 1) during each previous visit. The <br />ongoing observation of cracks (even well after mining had passed beneath the site and regrading) <br />confirms that the largest fill area of the pad is continuing to settle. This is an indication of <br />differential settlement and potential instability of the underlying materials. <br />No surface cracks were observe in the E2-51/52/54 MDW pad at the eastern end of recently <br />mined E-seam Longwall Panel E2 (Map 2). However, it was noted that the fill areas are <br />relatively small on the downslope side of this relatively large pad. <br />3.2.1 Location 1 <br />Location 1 is the drill pad for MDW E1-48. This location is near the eastern end of mined E- <br />seam Longwall Panel E1 and immediately downslope of the road connecting points I and I' (see <br />Map 2). Numerous cracks have been observed on the downslope side of this pad over several <br />field visits (including visits prior to any mining). <br />831-032.792 Wright Water Engineers, Inc. Page 6 <br />April 2011