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2005 Subsidence and Geologic Field Observations <br />Box Canyon, West Flatiron, Apache Rocks, <br />and South of Divide Mining Areas <br />4.15 Traverse N-N' <br />Traverse N-N' begins at the fork in the main access road (at M'), goes westward down Sylvester <br />Gulch, and ends at MDW 16-08. The drill road traversed to the well site is located above the <br />western part of mined longwall panel 16 in overburden (to B-Seam) ranging from about 950 to <br />1,050 feet. <br />The road cut in Sylvester Gulch at N begins in alluvium, estimated to be 50 to 75 feet thick, and <br />ends at N' in colluvium and weathered bedrock of the Barren Member of the Mesaverde <br />Formation. No subsidence features were observed. <br />4.16 Traverse O-O' <br />The drill and access roads traversed begin at the fork in the road, at M' and N, and end at Apache <br />Rocks. Traverse O-O' goes above mined longwall panels 16, 17, 13, and 13A. The overburden <br />' depth ranges from 1,000 to 1,350 feet. <br />Light gay to light brown soil and colluvium and local outcrops of siltstone and sandstone of the <br />' Batren Member of the Mesaverde Formation were observed in the road cuts. No subsidence <br />features were observed. <br />4.16.1 Location 13 <br />Location 13 is in the Apache Rocks subsidence area. The cracks, which are also described on <br />video narrative, are similar to their July 2004 appearance (Dunrnd 2004a), except they may <br />extend a few feet farther southwestwazd due to caving of the overlying colluvium and soil into <br />the underlying cracks. <br />A GPS position was obtained at the southern end of the most eastern crack in the area: 286, <br />654m E, 4,307,763m N (11'I'M, NAD 1983, circle of error: 3-5 m). This crack, which may be a <br />fraction of an inch wider than it was last year, has a maximum width of 4 inches (Figure 14). <br />831-032.710 Wright Water Engineers, Inc. Page 30 <br />November 2005 <br />