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pit (Photo 6). This may be attributed to the shallower depth of soil and rock <br />overburden removed. Iron oxide staining is common on many of the joint <br />surfaces. <br />5) Multiple narrow shear zones were observed along the temporary north and <br />south walls of the middle level of the quarry (Photo 7). The shear zones <br />varied in width from several inches to several feet across. The typical strike <br />of 015°, and a nearly vertical dip was conducive for viewing multiple <br />exposures due to the orthogonal intersection of the shear zone with the wall <br />orientations. <br />6) As noted in previous annual reports, a minor east-west striking unnamed <br />fault zone is mapped in the final pit wall in the northwest comer of the main <br />pit, and is also visible along the east wall of the main pit (Figure 3). The <br />rock within the fault zone is more broken and blocky, with parallel fracturing <br />and iron staining of joint surfaces common. Field measurements indicate <br />that the fault has an apparent dip of 80°-85° to the south and a general <br />strike azimuth of 260° to 270°. The width of the fault zone varies in the <br />main pit between approximately 20 and 50 feet. As mining progresses, the <br />north benches will continue to intercept the fault, which will increase the <br />footage that the fault is exposed along the final walls. The fault will <br />continue to be intercepted near the northwest comer of the pit as the pit is <br />excavated to the final depth. Based on the average dip of the fault, at <br />approximately an elevation of 6,260 feet, the fault may be exposed across <br />the floor of the main pit. It is unclear as to what impact the blockier rock will <br />have on slope stability. <br />7) Raveling conditions resulting from rock fragmentation during blasting and <br />subsequent freeze/thaw conditions exist along each wall in the quarry, but <br />appear more prevalent along the south wall. <br />-s- <br />