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' rock within the fault zone is broken and blocky, with parallel fracturing, iron-stained <br />surfaces and alterations in the rock. <br />' Field measurements taken in 2008 indicate that the fault has an apparent dip of 75° <br />to 80° to the south and a general strike azimuth of 260° to 270°. The width of the <br />' fault zone varies in the main pit between approximately 20 and 50 feet. Excavation <br />of the north and west benches will continue to intercept the fault, and the length of <br />' the 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 excavated <br />to the final depth. Based on the average dip of the fault, at approximately an <br />elevation of 6,260 feet, the fault may be exposed across the floor of the main pit. As <br />' mining in the main pit continues, monitoring of this interface will facilitate a better <br />understanding of how the slope will behave. <br />7) Raveling conditions resulting from rock fragmentation during blasting and subsequent <br />' freeze/thaw conditions exist along each wall in the quarry, but appear more prevalent <br />along the south wall possibly due to the north facing exposure. <br />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 two <br />' or more existing discontinuities, and daylighted in the exposed highwall. (See the <br />Wedge Stability Analysis section of this report for a complete description of this type <br />' of failure). The north wall pit slopes were modified in response to these events, and <br />based on continued photo documentation and visual monitoring since that time, no <br />additional movement has been detected (Photo 7). <br />' Based on the latest topographic map of the quarry provided to us (December, 2007), <br />the overall effective angle of the north pit walls has been modified over the last three <br />1 tachel & Associates <br />A SCHNA6f:l VMGt.EERit4G COMPANY