2009-03-04_REPORT - M1973021 - Laserfiche WebLink

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Ad& RMR spreadsheets for the highwalls are included in Appendix A. Scanline descriptions are MW included below: Aft The Bench 6880 scanline was approximately 400 feet long and was separated into 5 discrete Imk sections. The approximate orientation of the highwall is 340 degrees (north 20 degrees west). • Stations 0+00 through 0+75 consisted of granitic gneiss. The foliation strike varies in this area due to minor folding and ranges from 15 to 25 degrees. Foliation dips were • 15 to 20 degrees southeast, parallel or slightly out of the highwall, with average spacing of approximately 4 inches and foliation apertures were closed and smooth. The primary joint set strike ranges from 315 to 325 degrees and generally dips from 85 Ah to 90 degrees northeast. A secondary joint set is evident in this area and exhibits a A& strike of 85 to 90 degrees with dips of 75 to 85 degrees southeast. The spacing of joint set one averaged approximately 36 inches and the spacing of joint set two averaged approximately 20 inches. Joint apertures were closed with slightly rough faces. Stations 0+75 through 1+05 consisted of granitic gneiss. The foliation strike in this area varies due to a local syncline and ranges from 340 to 360 degrees with dips of 32 to 38 degrees northeast out of the face. Foliation spacing averages approximately 16 inches and foliation apertures were closed and smooth. The primary joint set strike ranges from 120 to 130 degrees and generally dips from 65 to 75 degrees southwest. The secondary joint set strike ranges from 15 to 20 degrees and generally dips 85 to 90 degrees southeast. Joint set spacing averages approximately 24 to 36 inches and joint apertures were generally closed and rough. The synclinal nature of the foliation in this area creates a minor potential for a plane failure of rock blocks sliding out of the face on the foliation joint. However, the "bowl" created by the foliation is cut off at 1+05 creating a partial interlock to the remainder of the highwall. Blocks from this area are anticipated to be limited in size and should be retained on the bench below the highwall. Stations 1+05 through 1+25 consisted of mixed granitic and biotite gneiss in a shear or slough zone. Foliation and joint orientations were indistinct due to the very close spacing of joints combined with the amount of slough material covering the highwall. The rock displays moderate iron staining and is assumed to be disintegrated under the sloughed material due to weathering from localized shear. Blocks observed in this area were generally less than 6 inches diameter due to the disintegrated nature of the rock. Raveling from this zone is anticipated to cause only local operational delays. Stations 1+25 through 2+20 consisted of massive granitic gneiss with planar jointing. The foliation strike ranges from 5 to 15 degrees and dips range from 10 to 25 degrees southeast, parallel or slightly into the highwall. Foliation average spacing was 36 inches and apertures were slightly rough and generally closed. The primary joint set strike ranges from 330 to 335 degrees and generally dips from 75 to 80 degrees northeast. The secondary joint set exhibits a strike of 55 to 60 degrees with dips of 85 to 90 degrees southeast. The average joint spacing was 30 inches and both joint sets exhibited moderately open to closed, slightly rough faces. -4- Morrison Quarry Annual Report 2008 February 2009 F A3919_038\Annual_Report _2008\Geotech_Report _2008\Annual_Report_2008_Geotech.doc