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3.1 North Quarry <br />No mining occurred in the North Quarry in 2011 and thus no new orientation data related <br />to mining activity was collected. Observations of the existing highwalls and benches were <br />conducted and compared with previous observations. Localized instabilities were <br />observed and local raveling of the rock faces has occurred. This raveling is likely due to <br />adverse jointing, rock weakened by alteration, and/or weathering actions such as freeze <br />thaw cycles. Blocks loosened in this fashion are generally small (less than approximately <br />11/2 foot in diameter) and collect on the benches. No major rock disturbances occurred in <br />the North Quarry in 2011. <br />Water continued to be stored in the North Quarry in 2011. No large scale seepage was <br />observed above the current water level of 6326.96 above MSL within the North Quarry. <br />3.2 Central Quarry <br />No mining occurred in the Central Quarry in 2011 and thus no new orientation data related <br />to mining activity was collected. Observations of the existing highwalls and benches were <br />conducted and compared with previous observations. Localized instabilities were <br />observed and local raveling of the rock faces has occurred. This raveling is likely due to <br />adverse jointing, rock weakened by alteration, and/or weathering actions such as freeze <br />thaw cycles. Blocks loosened in this fashion are generally small (less than approximately <br />1 1/2 feet in diameter) and collect on the benches. <br />Observations of the stabilized slope area indicate no visible movement or large erosional <br />features. Aggregate Industries provides survey support to monitor movement of this slope <br />as well. However, survey data is collected as conditions change and no survey was <br />completed in 2011. <br />Material stripped from areas in the South Quarry continued to be deposited in the Central <br />Quarry. The Central Quarry is being filled southward from the north end to an elevation of <br />approximately 6,500 feet. At the time of the field investigation, the quarry was <br />approximately two - thirds filled. Figure 3 is a photo of the fill placed in 2011. <br />3.3 South Quarry <br />Geotechnical data was collected for the areas mined in 2011. These areas include three <br />highwall and bench combinations at elevations 7350, 7250, and 6700 as approximately <br />shown on Figure 4. Bench development is on -going at all of the bench elevations <br />observed. The highwall faces are referred to by elevation for reference in this report. The <br />benches represent no increased depth of mining in the South Quarry from last year and <br />include expanded mining areas to the west (east facing). <br />The type of rock encountered in the highwalls is consistent with rock types described in <br />previous geotechnical addenda and primarily consists of fine to medium grained granitic <br />gneiss or biotite gneiss. Occasional pegmatitic intrusions, biotite schist zones and shear <br />- 3 - <br />Morrison Quarry Annual Report 2011 <br />P \235I4\ 133 - 23514 -1 2002 \ Deliverables \Dehv -0l- Annual Report \Annual_Report_2011_Geotech.doc <br />January 2012 <br />