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1100318 R0T0 0811 JRW1 31 <br />wedge extending between this area and the active floor of Area H at the time <br />of the initial Pikeview Landside movement had a relatively gently sloping <br />surface consistent with the type of ramp that would be needed for a haul road <br />to bring the limestone product out of the excavation (see cross section A-A', <br />Appendix 39). <br /> Ground cracking associated with the Pikeview Landslide was not limited to <br />the slope area east of the Rampart Range Fault, but rather crossed the fault <br />and expressed itself in the Pikes Peak Granite to the southeast of the <br />prominent failure scarp at the top of the quarry face as shown in <br />Photograph 10. The significance of this observation is that the initial <br />Pikeview Landside movement involved a laterally extensive portion of the <br />quarry that correlates well with the footprint of the minimally buttressed <br />weak Sawatch Formation clay beds. <br /> It is notable that the Sawatch Formation clay beds were not recognized in <br />previous subsurface investigations carried out in Pikeview Quarry. Based on <br />our review of the available boring logs, discussions with quarry personnel, <br />and our observations during drilling, the clay beds were not previously <br />recognized due to the standard drilling techniques previously utilized at the <br />site. Three generations of borings were evidently performed in the quarry <br />between the mid-1990s and 2008. The logs of these borings are attached in <br />Appendix 42. As is obvious from a review of these logs, no information is <br />provided regarding the type of drilling utilized. According to quarry <br />personnel, the most recent set of borings, TH-1 through TH-10 (see the <br />geologic map, Appendix 39), were conducted using an air percussion drill <br />rig. The objective of this drilling was to determine the depth to the Sawatch <br />Formation for the purposes of estimating the amount of minable product <br />remaining in the northern portion of the quarry. The drilling did not extend <br />into the Sawatch Formation, and, furthermore, it is highly unlikely a two <br />inch-thick clay bed could be identified by examining the powdery cuttings <br />produced by the air percussion drilling technique. The older generation of <br />borings did extend through the key interval to the underlying granitic