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<br />the Wedge Stability Analysis section of this report for a complete description of this <br />' type of failure). The north wall pit slopes were modified in response to these <br />events, and based on continued photo documentation and visual monitoring since <br />' that time, no additional movement has been detected (Photo 8). <br />' Based on the latest topographic map of the quarry provided to us (December, <br />2003), the overall effective angle of the north pit walls has been modified over the <br />' last three benches to an angle of 35° per LF&A recommendations in the May 2003 <br />report. The failure surfaces (i.e. the surfaces along which movement has <br />occurred) remain at a "residual strength" and therefore are less resistant to <br />additional loading. Although the slope configuration is currently stable, the failure <br />mechanism could potentially be reactivated upon removal of subsequent benches, <br />resulting in movement of additional material. <br />9) The highwall adjacent to the lower asphalt plant facilities and the area above the <br />highwall were visually inspected as part of the field reconnaissance inspections <br />performed in January 2008. As discussed in Section 2.0, the bedrock in the <br />' highwall of the asphalt plant is sedimentary, consisting of shales and sandstones <br />upturned to near vertical orientations, striking almost north-south. The highwall <br />' located immediately west and north of the bottom plant facility is currently stable, <br />with no evidence of highwall instabilities. No major cracks, settlement, or water <br />' ponding areas were observed at the ground surface above the highwall, and it <br />appears that the highwall is stable under the current conditions. <br />' In addition to the inspection of the hi9hwall observations along the access road to <br />' the upper asphalt plant facilities were also made with no surface cracks or <br />settlement noted. The road is aligned perpendicular to the strike of the nearly <br />' vertical bedded sedimentary rock, which is a favorable orientation for slope stability <br />along the access road. <br />-10-