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Spring 2008 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />• extension of the surface cracks as observed on June 4, 2008 is on the order of 2.5 to 3 feet. The <br />potential for more cracking and rockfall activity is high. Such activity is only expected to have <br />an effect on surface features, particularly vegetation. <br />Approximately 1,500 feet north of the rockfall/landslide area first observed in the spring 2007 is <br />a second rockfall area observed for the first time during the June 2008 site visit. This area is <br />described in this report as Location 9 (Map 1) and is located on the west side of another narrow <br />portion of the West Flatiron ridge between mined Longwall Panels 19 and 20. This site is <br />considerably smaller, as shown on Map 3. <br /> <br />The Box Canyon drainage has no human inhabitants or access roads. Continued <br />rockfall/landslide activities will affect the drill road on West Flatiron and the MDWs. However, <br />access to West Flatiron and the methane drainage well (MDW) pads is expected to be <br />unnecessary after the completion of Longwall Panel 18 during the summer of 2008. <br />• 831-032.790 <br />August 2008 <br />Wright Water Engineers, Inc. <br />Page 3