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SOUTH WALL <br /> ' Currently the South Wall has three distinct faces each with different orientations. Each of <br /> these faces and the orientation of the South Wall in the final mining plan were analyzed <br /> ' for stability conditions. Though the orientation of each of the faces of the South Wall <br /> varied, the results of the analysis reveal that the stability of each of the faces are <br /> ' controlled by the same discontinuities (Figures 8 - 11). Therefore, a separate description <br /> of the analysis of each face orientation will not be presented in this report. <br /> The South Wall of the quarry is currently stable. Two near north-south trending, steeply <br /> rdipping shear zones were identified along the South Wall in the lowest level of the quarry. <br /> No major potential stability problems exist currently due to these zones because of their <br /> near perpendicular orientation with respect to the South Wall; however, some ravelling <br /> may occur from these areas. The shear zones varied in width from one to five feet, and <br /> ' were continuous across the height of the lowest wall (see Photo 10). Some iron staining <br /> ' was evident along the shear zones, indicating that at one time, movement of water through <br /> these zones may have occurred. Several other locations along the South Wall where <br /> ' ravelling problems may occur were also identified during the field mapping activities. <br /> Photo 11 shows one area in particular, where a combination of over-break along the South <br /> ' Wall resulting from blasting operations, and weathering forces on the exposed face has <br /> resulted in a potential ravelling condition. <br /> During the field mapping effort in January, no evidence of ground water was identified. <br /> ' However, photographs from inspection of the quarry in June shows several damp areas <br /> and seeps along the south wall (see Photo 12). Though the occurrence of water along the <br /> ' South Wall may be seasonal, it is probable that this type of ground water presence will <br /> exacerbate the ravelling condition. <br /> Photo 13 reveals that the prominent potential failure mechanisms along the South Wall are <br /> 18 <br />