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Junuurv 1.5. 2008 <br />Page 11 <br />All four ol'the RMR indices are hyperbolic fits to the indices values above given by the <br />relations in Equation I. <br />RAIRI = -2e_4 x UCS 2 +0.105 x UCS +0.9 <br />RMR- = 6e-4 x RQD2 + 0.1134 x RQD + 2.79 <br />RMR; =0.012x 2000x(1-F125)-2000x(1-F125)2 x2e-6 <br />RMR4 =-1.0714x(FC+1)2 -1.0?14(FC+1)+32 <br />where (F.qn. I ) <br />F=[0.5x(FF-3)(5-FF)+FFJx[0.jx(FT-3)(FT-1)+FT] <br />1+P+R+FD <br />4 <br />The fracture frequency factor. F, is scaled by the fracture frequency index and the <br />fi-acture type index. The fracture condition factor. F(', is the average of the l6ur fracture <br />condition indices infilling, planarity, roughness, and fracture durability. <br />The rock characteristics from the logs are summarized in plots of lithologic layer versus <br />RQD and RMR. Figures 5 through 13 show examples of the rock mass characterization for <br />seven boreholes within the landslide (07-GI I-CCR through 07-G17-CCR) and the two boreholes <br />in the K-Pit area (07-(.iX5-CC'R and 07-CiX6-CCR). The logs from boreholes drilled inside the <br />landslide block indicate the following: <br />• The shear zone has been identified in 8 of 9 boreholes at an average depth of 96 a below <br />. round in the I.-Roof mudstone layer. <br />• There is extensive disturbance above the slip plane along the perimeter of the landslide <br />block, especially on the east side adjacent to the G-Dip Pit box cut. This disturbance is <br />the result of material from the pit floor being buckled up into the pit floor and bulking the <br />material above it. <br />• Open fractures were observed in nearly all holes in upper sandstone units. The massive <br />packed than expected immediately after the landslide. <br />block is likely more loosely, <br />• Only one borehole shows disturbance below L-Seam, but the projection of the slide plane <br />is consistent with other holes. This is likely due to a roll in the bedding which the slide <br />plane sheared through. <br />• Low RQD and low rock mass strengths above shear zone are primarily due to slope <br />related ground disturbance and the degree of'disturbance is dependent on local fracturing <br />and fracture orientations. <br />• The rock mass disturbance is primarily due to opening of' larger-scale, tightly-packed <br />tractures exacerbated by the landslide sliding downhill on undulating bedding surtaces. <br />Agapito Associates, Inc.