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quantity in the walls 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 a <br />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 />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 />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 fault <br />may be exposed across the floor of the main pit. As mining in the main pit <br />continues, monitoring of this interface will facilitate a better understanding of <br />how the slope will behave. It is unclear at this time as to what impact the <br />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_ <br />