2010-02-02_REPORT - M1973021 (2)

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Figure 8 is a photo documentary of the features observed in Bench 6760. The Bench 6700 scanline was approximately 330 feet long and consisted of one section. The approximate orientation of the highwall observed for the scanline is northwest- southeast. Stations 0+00 through 3+30 consisted of highly weathered granitic gneiss. The strike of the foliation varies due to the wavy nature of the jointing and ranges from 315 to 330 degrees. Foliation dips range from 20 to 40 degrees southwest. The average spacing of the foliation was approximately 4 inches and the foliation displays slightly rough to rough surfaces with apertures that are moderately open and infilled with clay. The primary joint set strike ranges from 70 to 80 degrees and generally dips from 165 to 190 degrees northwest. The secondary joint set strike ranges from 75 to 85 degrees and generally dips from 50 to 60 degrees southeast to southwest. The joint set average spacing was 6 inches and exhibited closed, rough faces The highwall beyond scanline station 3+30 consisted of in place rock that was exposed during removal of the overburden and has not yet been mined. This portion of the highwall was not included in the scanline. 4.0 RESULTS AND DISCUSSION Observations of the North Quarry indicate little change in the finished slopes with the exception of the reclamation conducted on the North Fill Slope and the North Repository Area. Local rock sloughing was observed and classified as minor based on rock accumulations observed on bench surfaces throughout the North Quarry. The condition of the remaining North Quarry is anticipated to remain stable with only small scale rockfall expected to occur. Observations of the Central Quarry indicate little change in the finished slopes. Partial reclamation work will continue in 2010 and will consist of continued placement of stripped material within the quarry below approximate elevation 6500. Local rock sloughing was observed and was classified as minor based on rock accumulations observed on bench surfaces throughout the Central Quarry. The general condition of the highwalls is anticipated to remain stable with only small scale rockfall expected to occur. The baseline rock conditions described in Amendment 3 to Mining Permit M-1973-021 are "competent" for granite or biotite gneiss and "poor" for shear zones or highly to extremely weathered zones that have the potential to decrease the stability of the slope. The conditions observed in highwalls mined in 2008 in the South Quarry indicate that the rock is predominately "competent" with localized areas of "poor". Generally, the localized areas of "poor" are located near the end of highwalls or in areas of initial highwall development and several are anticipated to be "competent" once further rock is removed for processing. -7- Morrison Quarry Annual Report 2009 February 2010 P:\23514\133-23514-10003\Deliverables\Deliv-0l-Annual Report\AnnuaLRepor_2009_Geotech, 1-25-IO.doc