2013-01-31_REPORT - M1973021 (2)

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degrees. Foliation dips ranged between 25 and 60 degrees southwest. Foliation spacing ranges from approximately 4 inches to more than 2 feet, and foliation apertures were tight to moderately open and slightly rough to rough. The primary joint set strike ranges from 135 to 175 degrees and generally dips from 40 to 82 degrees northeast. A second primary joint set is evident in this area and exhibits a strike of 70 to 75 degrees with a dip of 65 degrees northwest. The spacing of the primary joint sets varied widely, but averaged approximately 18 inches. Joint apertures were tight to moderately open with slightly rough to rough faces. • A secondary joint set is evident in this area and exhibits an average strike of 305 to 310 degrees with an average dip of 48 degrees southwest. The spacing of the secondary joint set varied, but averaged greater than 6 feet. Joint apertures were moderately open with slightly rough to rough faces. Small blocks may form in this area due to the orientation of the highwall and jointsets of the rock. These blocks are anticipated to be limited in size, and should be retained on the bench below the highwall. Due to the moderately to highly fractured nature of the rock, raveling is to be expected in this area. Raveling from this zone should be retained on the bench below the highwall and is anticipated to cause only local operational delays. The next two scanline sections are unique due to the presence of a shear zone and highly altered sillimanitic gneiss. The sillimanitic gneiss appears in the Bench 6700 highwall at approximate station 0 +90 and extends to a height of approximately 25 feet (half of the total highwall height) near station 1 +25 (45 degree dip to the south) where it remains horizontal through the end of the highwall at approximate station 3 +00 (see Figure 9). • Stations 0 +40 through 2 +45 (non -shear zone) consisted of moderately fractured granitic gneiss. The foliation strike in this area varies due to minor folding and ranges from 10 to 360 degrees with dips ranging from 18 to 60 degrees southwest. Foliation spacing ranges from approximately 4 inches to approximately 2 feet, and foliation apertures were moderately open to open and slightly rough to rough. The primary joint set strike ranges from 150 to 340 degrees and generally dips from 55 to 90 degrees southwest to northeast. A second primary joint set strike ranges from 60 to 85 degrees and generally dips 58 to 90 degrees northwest. The spacing of the primary joint sets varied widely, but averaged approximately 18 inches. Joint apertures were moderately open to open with slightly rough to rough faces. • Stations 0 +90 through 3 +00 (sillimanitic gneiss and shear zone) consisted of granitic /sillimanitic gneiss that has been altered and is part of a shear zone associated with the fault mapped in the area (Scott, 1972). RMR data was gathered on the remnant foliation and jointsets observable between stations 0 +90 and 3 +00. The foliation strike in this area varies due to minor folding and ranges from 25 to 350 degrees with a dip ranging from 15 to 45 degrees southwest. Foliation spacing ranges from approximately less than 2 inches to approximately 1 foot, and foliation apertures were moderately open to very wide and smooth to slightly rough. The primary joint set strike ranges from 5 to 350 degrees and generally dips from 60 to 88 degrees 7 Morrison Quarry Annual Report 2012 P \23514\ 133 - 235 14- 13002\Deliverables\Dehv -01 -2012 Annual Report \Ann ual_Report_2012Geotech doc January 2013