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Spring 2009 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />• formalized establishment. Two photographic observation points were established in the spring of <br />2007, seven more points were established in the fall of 2007, and two additional points were <br />established during the spring of 2008 site visit. No new points were established during the spring <br />of 2009 site visit. <br />The two spring 2007 photographic observation points include one that overlooks the Dry Fork <br />drainage, the Minnesota Creek Reservoir, the Deer Creek Ventilation Shaft and Escapeway, and <br />the lower reaches of the Deer Creek drainage. This location will be used regularly to assess <br />changes that may occur as mining of the E -seam progresses through the area. The second <br />photographic observation point established in the spring of 2007 is on the west side of Sylvester <br />Gulch and provides a good vantage point to view the rockfall and landslide area at the headscarp <br />of Box Canyon. This location is approximately 4,300 feet north of the previous location <br />established for this purpose. <br />Seven additional photographic observation points were established in the fall of 2007 to view <br />• rockfalls and landslides in the Box Canyon mining area, the dam and landslide construction in <br />the Minnesota Reservoir area, and the Highway 133 landslides (see Map 1). <br />Two additional photographic observation points were established during the spring 2008 field <br />visit. One location is from near the train loadout facility north of Highway 133 where a full view <br />of the large sandstone rockfall along the south side of North Fork can be readily observed. This <br />site has been visited and photographed previously but was added as a photographic observation <br />point for continued review. The second spring 2008 photographic observation point was <br />established along the Box Canyon road to assess any changes to a series of sandstone outcrops on <br />the east side of the canyon immediately above Longwall Panel 18 where the B -seam overburden <br />thickness is between 700 and 800 feet. <br />The number designations for these photographic observation points do not reflect the order in <br />which they were established but rather the order in which they were visited during the fall 2007 <br />field visit. This convention will be maintained (see Map 1 and 2) with the exception of any new <br />photographic observation locations added as deemed appropriate. <br />831 - 032.791 Wright Water Engineers, Inc. Page 15 <br />November 2009 <br />