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than one inch up to 4 feet. Foliation surfaces generally are slightly rough and are usually closed. <br />When foliation surfaces are open or exposed, the aperture is up to one inch and the foliation faces <br />are typically slightly weathered displaying iron staining. The foliation generally does not contain <br />any infill material. The highwalls observed were dry and seepage through the rock is not <br />anticipated. Average RMR values calculated for the rock in this area range from 55 to 65 <br />indicating fair to good rock. Joint orientation field data and RMR spreadsheets for the highwalls <br />are included in Appendix A. <br />The lower highwall scanline was approximately 300 feet long and was separated into 5 discrete <br />sections. <br />Stations 0+00 through 0+35 consisted of massive granitic gneiss. The foliation strike <br />varies in this azea due to the anticlinal/synclinal nature of the gneiss and ranges from 210 <br />to 310 degrees. Foliation dips were 20 to 35 degrees, parallel or slightly out of the <br />highwall, with average spacing of approximately 12 inches and foliation apertures were <br />slightly open to closed and slightly rough. The primary joint set strike ranges from l05 to <br />115 degrees and generally dips from 75 to 85 degrees. A secondary joint set is evident in <br />this area and exhibits a strike of 45 to 55 degrees with dips of 70 to 80 degrees. The <br />spacing of both the joint sets averaged approximately 15 inches andjoint apertures were <br />slightly open to closed with slightly smooth to rough faces. <br />Stations 0+35 through 0+50 consisted of a 15 foot wide bowl shaped azea of disintegrated <br />granitic gneiss. The foliation strike in this area ranges from 295 to 305 degrees and dips <br />were 35 to 45 degrees, parallel or slightly out of the face with indistinct but likely very <br />close spacing. Other joint sets were indistinguishable in the face due to the highly <br />fractured nature of the rock. This area has the potential to create instability in the <br />highwall, however, the disintegrated nature of the rock is anticipated to limit the size of <br />blocks that could potentially loosen from the wall and should cause only minor safety <br />hazards or operational delays. <br />Stations 0+50 through 0+75 consisted of massive granitic gneiss. Foliation strike in this <br />area ranges 330 to 340 degrees and dip values range from 65 to75 degrees with slightly <br />out of the highwall, with average 12 inch spacing and closed, slightly rough, wavy faces. <br />The primary joint set strike ranges from 65 to 75 and generally dips from 80 degrees to <br />near vertical. A secondary joint set is evident in this area and exhibits a strike of 120 to <br />130 degrees with dips of 45 to 55 degrees. The spacing of both the joint sets averaged <br />approximately 9 inches and joint apertures were closed with slightly smooth to rough <br />faces. <br />Stations 0+75 through 1+35 consisted of highly weathered biotite gneiss and biotite schist. <br />Foliation strike ranges from 240 to 250 degrees has a shallow dip of 15 to 25 degrees with <br />tight spacing, up to a maximum of 6 inches. The foliation dip abruptly changes from <br />station 0+75 to 0+90 to near vertical due to localized folding. Joint attitudes and dips <br />were indistinct in this area. It is likely that the high degree of folding in this area caused <br />partial disintegration of the rock that allowed it to become highly weathered. Blocks <br />observed in this area were less than 12 inches diameter, likely due to the disintegrated <br />nature of the rock and the tight joint spacing. Raveling from this zone is anticipated to <br />cause only minor safety hazards or local operational delays. <br />r:U919_038~Annual_Report_200641nnual_Report_2006.dac - 3 - .4pfll 207 <br />