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4.2 Traverse 1 -1' <br />Spring 2012 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <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 El and E2 <br />and mined E -seam Longwall Panel E3 to a connection with Dry Fork Road near the eastern edge <br />of Section 34, T13S, R9OW of the 6 P.M. (see Maps 1 and 2). <br />Weathered and fractured siltstone, claystone and sandstone bedrock are exposed in several <br />roadcuts along the steeper portions of this traverse. Flatter portions of the traverse are generally <br />stable and on mostly soil and colluvium derived from the Wasatch Formation and from intrusive <br />rocks of the West Elk Mountains that surficially blanket much of the SOD mining area. <br />Overburden depths along this traverse vary from 1,390 to 1,600 feet over the B -seam and 1,100 <br />to 1,300 feet over the E -seam. <br />Previous spring reports have discussed the steep side slope of the fill portion of the MDW El- <br />52/53/55 well pad. This pad (along with the MDW E1 -48 pad) had been reclaimed as of our <br />spring 2012 field visit. There was no evidence of movement on the downslope side of the <br />reclaimed pad at that time. <br />Differential settlement cracks on the outside (downslope) edge of the MDW E3 -55 pad as <br />previously observed could not be relocated at the time of our spring 2012 field visit. <br />4.3 Traverse J <br />Traverse J -J' begins at Traverse I -I' and continues in a west/northwestward direction along a <br />ridgeline across most of mined E -seam Longwall Panel E1 (and a small portion of mined E -seam <br />Longwall Panel E2) to numerous MDW drill pads (see Maps 2 and 4). Overburden depths along <br />this traverse vary from 1,090 to 1,460 feet over the B -seam and 850 to 1,230 feet over the <br />E -seam. <br />This traverse is generally flat and stable on soil and colluvium derived from the Wasatch <br />Formation and from intrusive rocks of the West Elk Mountains overlying consolidated bedrock <br />831 - 032.794 <br />November 2012 <br />Wright Water Engineers, Inc. Page 9 <br />