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<br />shows two pairs of intersecting planes that have plunge lines inclined steeper than the <br />' friction angle, but just steeper than the inclination of the slope face. As such both these <br />wedges are considered kinematically stable. However, if isolated pairs of planes should <br />intersect with shallower plunge angles due to natural variability, unstable blocks could <br />daylight in the slope face and therefore these two pairs (P4:P6 and P5:P2) should <br />' continue to be monitored as the excavation continues. <br />' The wedge stability analysis for the southeast wall indicates six pairs of intersecting <br />planes that have plunge lines inclined shallower than the slope face, but only one of <br />' these (P4:P6) is inclined steeper than the friction angle. The intersection of the planes <br />for discontinuity sets P-4 and P-6 is inclined parallel to the slope face and so potentially <br />unstable wedges are likely to be surficial in nature. <br />As mentioned previously for the east wall, the individual benches along the south walls <br />with near vertical faces enable additional discontinuities to form potential wedges that <br />' may slide during the temporary conditions prior to reclamation. Wedge failures limited to <br />individual benches have been consistently observed in the past along the south walls. <br />' The recently identified discontinuity set F-3, appears to dominantly influence the <br />' potential for failures along the southwest walls that could be either wedge blocks (F3:P6 <br />whose plunge line is inclined just less than the failure envelope) of planar blocks (e.g. <br />' F3:P2:P1 or F3:P6:P1, etc.). <br />' In previous annual reports, toppling about discontinuity plane P-1 also existed as <br />another mechanism of potential block movement for the southeast wall. However, as <br />' shown on Figure 16 both the slope face and discontinuity plane P-1 no longer share the <br />same basic strike. A review of photographs during previous annual studies does <br />' indicate that there are some continuous surfaces that form the face of the south wall. <br />However, none of these surfaces appear to be identified as plane P-1, which has an <br />' average dip of 76° to the south. <br /> <br />-18-