2013-01-31_REPORT - M1973021 (2)

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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. The discontinuities dipping to the northeast may be more prone to raveling. Raveling from this zone should be retained on the bench below the highwall and is anticipated to cause only local operational delays. southwest. A second primary joint set strike ranges from 248 to 255 degrees and generally dips 63 to 78 degrees southeast. The spacing of the primary joint sets varied widely, but averaged approximately 18 inches. Joint apertures were moderately open to very wide with smooth to slightly rough faces. The rock in this area appears to exhibit low to very low compressive strength and is completely weathered. Figure 9 is a photo documentary of the features observed on bench 6700. Bench 6640 The Bench 6640 scanline is approximately 2,680 feet long and was separated into 10 discrete sections. The approximate orientation of the highwall varies between 0 degrees (north) and 350 degrees (north 10 degrees west). A granitic pegmatite was observed at approximate station 2 +15 and was dipping 60 degrees to the north and a nearly vertical mafic dike was observed between approximate stations station 13 +70 and 13 +75. • Stations 0 +00 through 1 +60 consisted of highly fractured granitic gneiss. The foliation strike varies in this area due to minor folding and ranges from 170 to 335 degrees. Foliation dips ranged between 20 and 40 degrees southeast. Foliation spacing ranges approximately from less than 2 inches to approximately 1 foot, and foliation apertures were moderately open to open and slightly rough to rough. The primary joint set strike ranges from 5 to 340 degrees and generally dips from 60 to 80 degrees southwest. A second primary joint set is evident in this area and exhibits a strike of 100 to 105 degrees with a dip of 70 to 80 degrees northeast. The spacing of the primary joint sets varied widely, but averaged approximately 6 inches. Joint apertures were moderately open to open with slightly rough to rough faces. • Stations 1 +60 through 3 +10 consisted of moderately fractured granitic gneiss. The foliation strike varies in this area due to minor folding and ranges from 180 to 220 degrees. Foliation dips ranged between 12 and 25 degrees southeast. Foliation spacing ranges approximately from 2 inches to more than 2 feet, and foliation apertures were tight and slightly rough to rough. The primary joint set strike ranges from 330 to 350 degrees and generally dips from 68 to 80 degrees southwest. A second primary joint set is evident in this area and exhibits a strike of 75 to 95 degrees with a dip of 85 to 88 degrees northeast. The spacing of the primary joint sets varied widely, but averaged approximately 18 inches. Joint apertures were moderately open with slightly rough to rough faces. 8 Morrison Quarry Annual Report 2012 P \23514 \133 - 23514- 13002\Deliverables\Dehv -01 -2012 Annual Report \Annual_ Report _2012_Geotech doc January 2013