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1 <br />' tit <br />i <br />th <br />ll <br /> quan <br />y <br />n <br />e wa <br />s exposed during the current investigation. This foliation <br />' set is being referred to as F-3. <br /> 6) The rock mass exposed in the middle level of the quarry continues to have <br /> a higher fracture density and be more weathered than the rock excavated in <br /> the main pit. Iron oxide staining is common on many of the joint surfaces. <br />' <br /> 7 Multiple narrow shear zones that were noted in the past few investigations <br />' have also been observed during this investigation along the temporary north <br /> wall of the middle level of the quarry (Photo 9). The shear zones varied in <br />' width from several inches to several feet across. The typical strike of the <br /> shear zones were 015°, or almost perpendicular to the wall exposure. <br /> <br /> 8) As noted in previous annual reports, a minor east-west striking unnamed <br />' fault zone is mapped in the northwest corner of the main pit, and is also <br /> visible in the east wall of the main pit (Figure 3). The rock within the fault <br />' zone is more broken and blocky, with parallel fracturing and iron-stained <br /> surfaces. Field measurements indicate that the fault has an apparent dip of <br />' 80° to 85° to the south and a general strike azimuth of 260° to 270°. The <br /> width of the fault zone varies in the main pit between approximately 20 and <br /> 50 feet. Excavation of the north benches will continue to intercept the fault, <br /> and the length of the fault exposure in the walls will increase as mining <br /> progresses. The fault will continue to be intercepted near the northwest <br /> corner of the pit as the pit is excavated to the final depth. Based on the <br />' average dip of the fault, at approximately an elevation of 6,260 feet, the <br /> fault may be exposed across the floor of the main pit. As mining in the main <br />' pit continues, monitoring of this interface will facilitate a better <br /> understanding of how the slope will behave. It is unclear at this time as to <br /> what impact the fault will have on overall slope stability. <br />' 9) Raveling conditions resulting from rock fragmentation during blasting and <br />subsequent freeze/thaw conditions exist along each wall in the quarry, but <br />' -12-