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Fall 2008 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />• <br /> <br />• <br />Figure 8. Fall 2008 photograph of a subsidence crack located on the uphill <br />side of the drill road to West Flatiron. Gradual weathering along the <br />sandstone face can be discerned from comparison of several photographs <br />at this location. <br />5.4.2 Location 3 <br />Figure 9 is of' a rocklall located above the drill road to West Flatiron as described in previous <br />annual and semi-annual reports. The fall. ,Nhich occurred on June 30, 2004, is located above the <br />north edge of" the central part of mined Longwall Panel 14. A photograph of the same rocklall <br />area taken during the summer of 2006 is provided as Figure 1 (I li)r comparison. <br />The overburden depth to the a-seam at this location is about 1,950 feet. Photographic <br />comparisons of this area since 2004 suggest that no additional subsidence related effects have <br />occurred, although additional rocklall (most likely 1'r0111 natural processes) may still occur in <br />these rugged clilTareas. <br />831-032.790 Wright Water Engineers, Inc. <br />December 2008