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1100318 R0T0 0811 JRW1 16 <br />4 Landslide Damage to Engineered Improvements <br />On the morning of December 2, 2008, a large slope failure, herein referred to as the Pikeview <br />Landslide, occurred on the highwall on the west side of the quarry above the lowest bench of <br />Area H. Photograph 9 and Photograph 10 are aerial photographs of the site and the Pikeview <br />Landslide taken on December 5, 2008. Photograph 9 shows an overview of the slope failure <br />looking west, and Photograph 10 shows the top (headscarp) of the slope failure looking <br />northwest. Photograph 11 and Photograph 12 are ground photographs of the bottom (toe) of the <br />landslide taken on December 3, 2008. Appendix 35 contains December 2008 landslide ground <br />and aerial photography. The Pikeview Landslide caused substantial damage to the engineering <br />improvements described in Section 3. <br />Eyewitness accounts of the Pikeview Landslide are documented in a February 23, 2009 United <br />States Mine Safety and Health Administration (MSHA) report as follows: <br /> A front-end load operator on the floor of the lowest level of Area H described <br />the initial Pikeview Landslide motion involving the upper part of the first <br />bench above the pit floor, followed by the entire highwall “pushing out,” <br />while the pit floor appeared to heave about 1 to 1½ feet. Subsequent <br />Pikeview Landslide motion was described as resembling “cake batter being <br />poured into a pan.”45 <br /> A quarry employee, who is a resident in a nearby neighborhood from which <br />he could view the upper half of the west slope, observed that the initial <br />movement of the Pikeview Landslide involved the upper pit slope just below <br />the natural topographic spur referred to as the “middle peak.” This upper <br />portion reportedly moved downward for about 6 seconds, then stopped for <br />several seconds; the motion resumed for several seconds, then stopped again. <br />The third and final motion reportedly included the opening of the large “rift” <br /> <br />45 United States Department of Labor, Mine Safety and Health Administration, Pittsburgh Safety and Health <br />Technology Center, Mine Waste and Geotechnical Engineering Division, Report No. MW09-008, February 23, <br />2009, pages 4-5 (Appendix 36)