2010-02-02_REPORT - M1973021 (2)

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highwall. A secondary joint set is evident in this area and exhibits a strike of 265 to 270 degrees with dips of 80 to 90 degrees southeast. The spacing of joint sets one and two varied widely, but averaged approximately 36 inches. Joint apertures were tight to moderately open with slightly 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. Stations 4+75 through 5+75 consisted of moderately to highly fractured granitic gneiss. The foliation strike in this area varies due to minor folding and ranges from 305 to 340 degrees with dips of 15 to 40 degrees southwest into the face. Foliation spacing averages approximately 4 inches and foliation apertures were closed and smooth. The primary joint set strike ranges from 160 to 180 degrees and generally dips from 45 to 80 degrees northeast out of the highwall. The secondary joint set strike ranges from 250 to 270 degrees and generally dips 60 to 85 degrees southeast. The spacing from joint set one averaged approximately 36 inches. The spacing on joint set 2 varied widely, but averaged approximately 8 inches. The apertures of both joint sets were generally closed to moderately open and slightly rough. 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. Figure 6 is a photo documentary of the features observed in Bench 6880. The only mining that occurred in 2009 on Bench 6820 removed the highwall observed last year between 2008 scanline stations 0+00 and 2+50. The removed area provides access for a haul road, and there is no highwall remaining at this location, therefore no scanline was conducted on this bench. Figure 7 shows the current conditions at this location. The Bench 6760 scanline was approximately 1360 feet long and was separated into 5 discrete sections. The approximate orientation of the highwall observed is approximately east-west for stations 0+00 through 2+15 and 5+70 through 8+25 and approximately north- south for stations 2+15 through 5+70 and 8+25 through 13+60. The material in the highwall from station 8+25 to 13+60 is material that is in the process of being mined. Stations 0+00 through 0+90 consisted of highly fractured and weathered granitic gneiss. The strike of the foliation varies due to minor folding and ranges from 220 to 245 degrees. Foliation dips range from 20 to 30 degrees southeast. The average spacing of the foliation was approximately 4 inches and the foliation displays slightly rough to rough surfaces with apertures that are generally tight. Due to the highly fractured nature of the rock and inconsistent joint pattern in this area, only one prominent joint set was observable. This joint set strike ranges from 195 to 205 degrees and generally dips from 70 to 80 degrees southeast. The joint set average spacing was 6 inches and exhibited closed, rough faces. -5- Morrison Quarry Annual Report 2009 February 2010 P:\23514\133-23514-10003\Deliverables\Deliv-0l-Annual Report\Annual_Re[rort_2009_Geotech, 1-25-IO.doc