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pit should not cause toppling failure in the overall pit wall. On a bench scale, some toppling <br /> failure may occur especially during and immediately following planned blasting. Large catch <br /> benches were included in the previously submitted plan and will have sufficient capacity to catch <br /> small bench scale failures. <br /> The two secondary fracture orientations are sub-perpendicular to the direction of mining and will <br /> cause potential small wedge failures on a bench wide scale resulting in minimally invasive clean <br /> up issues during each cycle of blasting and mining. The primary fracture orientation trending <br /> east-west provides cause for concern with respect to mining and careful care should be taken to <br /> avoid daylighting fractures oriented along this trend. Care in mining can be accomplished by <br /> maintaining an overall slope angle lower than that of the fracture dip. This is maintained by <br /> mining at a 1 H:1 V slope resulting in a site wide scale—45' slope and a bench wide scale of <br /> 1 H:1 V with 30 foot high and 30 foot wide benches. <br /> The greatest consideration in mining the surface is the northeast-southwest trending fault and <br /> shear zone (Figure 6). Multiple faults and many fractures are found within this zone with average <br /> orientation measurements of 081/86 south and 226/90 NW. The trend of the entire shear zone is <br /> roughly northeast-southwest while individual faults within the overall —20 feet of highly altered <br /> and weathered granite,the product of fluid flow and fault movement. An indeterminate amount <br /> of vertical movement has occurred on the fault during as early as 35 million years ago and as late <br /> as 70 million years ago during the Sevier and Laramide Orogenies, the creation of the present <br /> day Rocky Mountains. As the area is no longer tectonically active, movement along the fault and <br /> shear zone is not anticipated or expected. <br /> Mining through the fault zone should be conducted carefully as blasted rock may experience <br /> more movement due to an increased fracture density. However, careful blasting techniques such <br /> as cushion blasting may be utilized. Blasted fault zone rocks will behave in the same way that <br /> blasted rock throughout the rest of the site will behave with respect to post blast behavior and <br /> slump. Only small wedge failures may occur near the fault zone but the bench design provides <br /> 30-foot-wide benches that reach 30 feet in height resulting in an overall 1 H:1 V mining slope that <br /> is more than adequate to catch any small failures produced by fault rock movements produced by <br /> blasting. Simply regrading and smoothly of blasted fault rock will need to be considered. <br /> Rose Red Quarry Geotechnical Report 10 1,r,,rw cl and lsrnridlre r,,, <br />