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depth of the main pit, the frequency of the use of the pump to maintain water level <br />has increased. <br />' 6) As noted in previous annual reports, a minor east-west striking unnamed fault is <br />mapped in the northwest corner of the main pit, and is also visible in the east wall <br />' of the main pit (Figure 3) and recently has been re-exposed on the west and <br />northwest walls for the new sump excavation. The rock within the fault zone is <br />' broken and blocky, with parallel fracturing, iron-stained surfaces and alterations in <br />the rock (Photo 7). <br />Field measurements indicate that the fault has an apparent dip of 75° to 80° to the <br />' south and a general strike azimuth of 260° to 270°. The width of the fault zone <br />varies in the main pit between approximately 20 and 50 feet. Excavation of the <br />north and west benches will continue to intercept the fault, and the length of the <br />fault exposure in the walls will increase as mining progresses. The fault will <br />' continue to be intercepted near the northwest corner 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 the floor <br />of the main pit. As mining in the main pit continues, monitoring of this interface will <br />facilitate a better understanding of how the slope will behave. <br />' 7) Raveling conditions resulting from rock fragmentation during blasting and <br />subsequent freeze/thaw conditions exist along each wall in the quarry, but appear <br />' more prevalent along the south wall possibly due to the north facing exposure. <br />t 8) A section of the northeast wall of the main pit originally experienced planar failure <br />along the foliation planes in 1998. Following removal of the next bench in 1999, a <br />' larger section of the wall that is approximately 350 feet wide by 250 feet high <br />experienced planar failure. As described in previous annual reports, the failure is <br />' believed to have occurred when a continuous foliation plane was intersected by <br />two or more existing discontinuities, and daylighted in the exposed highwall. (See <br /> <br />-9- <br />LJ