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Fall 2007 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />C7 <br />• <br />Figure 16. The balanced (middle) and perched rock on the cliff edge (right) remain <br />unaffected by mining in longwall panel 19 as of fall 2007. <br />• <br />5.3.4 Location 5 (Location 4 of the Spring 2007 Field Visit) <br />Cracks that were initially observed in 2006 in graded material above the northeastern edge of <br />mined longwall panel I ~), im the northern edge ot- vIDWs 19-O l , 19-02, and 1 ~)-0~, arc now <br />nearly completely healed and scaled. Based on their location, these cracks were within the area <br />of maximum tensile strain. The overburden depth to the B-seam in this area is about 2?~0 feet. <br />The drill site is constnicted primarily in soil and colluvium derived from the Wasatch Formation. <br />831-032.780 Wright Water Engineers, Inc. Page 28 <br />November 2007 <br />