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Spring 2008 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />0 5.6 Traverse F-F' <br />Traverse F-F' is a short traverse that starts at the fork in the main West Flatiron drill road (E-E' <br />traverse) and heads westward to the drill pad containing MDWs 19-04 and 19-05 (Location 8). <br />This traverse is above the eastern part of mined Longwall Panel 19 primarily in clays and silts of <br />the Wasatch Formation. Overburden depth to the B-seam is 2,200 to 2,250 feet. <br />Location 8, which also is Photographic Observation Point 2, provides a good southward view of <br />the rockfall/landslide area above mined Longwall Panel 22. This is an annual observation <br />location for this area because this vantage point provides a good view of the steep cliffs along the <br />west side of West Flatiron. This point was also used this year to photograph a new <br />rockfall/landslide at Location 9 (approximately 1,500 feet north of Location 5). <br />5.6.1 Location 8 <br />The fresh cracks that were observed near the southwest corner of drill pad MDWs 19-04 and 19- <br />05 at D' of traverse D-D' in the spring 2007 field visit became difficult to observe during the fall <br />2007 visit (Figure 21) and were substantially increased in spring 2008. In fact, a large portion of <br />the southwest corner of the drill pad has dropped as much as 10 feet from its original elevation <br />(see Figures 22 and 23). The dropped portion of the pad is comprised of several stepped scarps <br />measuring 2 to 6 feet in offset. <br />• 831-032.790 Wright Water Engineers, Inc. <br />August 2008 <br />Page 32