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Spring 2009 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mininq Areas <br />• 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 6). <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 6, which also is Photographic Observation Point 2, provides a clear southward view of <br />the rockfall /landslide area, first observed in July 2005, above mined Longwall Panel 22. This is <br />an annual observation location for this area because this vantage point provides a clear view of <br />the steep cliffs of the massive sandstone of the Ohio Creek Member of the Mesaverde Formation <br />along the west side of West Flatiron. This point was also used in 2008 to photograph a new <br />rockfall /landslide at Location 7 (approximately 1,500 feet north of Location 4). This site is not <br />visible from Traverse E -E' and is therefore included as part of this traverse. <br />• 5.6.1 Location 6 <br />The previously noted failure of the southwest corner of drill pad MDWs 19 -04 and 19 -05 at F' of <br />Traverse F -F' in the spring 2008 field visit is no longer visible due to the reclamation of the drill <br />pad and surrounding area (Figure 23). However, there is notable slumping and downward creep <br />of the soil profile toward and over a sandstone ledge at the lower end of this reclaimed area. This <br />cannot be readily observed from Location 6. However, Figure 24 shows the area as observed <br />from Photographic Observation Point 1 where evidence of downslope movement of vegetation, <br />soil and colluviums toward and over a lower sandstone ledge can be readily observed. Figure 10 <br />in Section 5.1.2 of this report also provides evidence of this downslope movement creep of <br />vegetation, soil and colluviums beneath the reclaimed MDS pad. <br />831- 032.791 Wright Water Engineers, Inc. Page 36 <br />November 2009 <br />