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5. Waste Rock Embankment <br />~l <br />The existing bench at the Whirlwind portal was made from waste rock excavated from the driving <br />of the decline and the two short developmental drifts at the base of the decline, The slope of this <br />bench was reclaimed previously but will be re-disturbed since the bench will be expanded using <br />waste rock produced from underground mining operations. See Map C-lA for the configuration of <br />the current bench. See Map C-2 for the plan view of the expanded waste rock embanlanent. <br />The waste rock pile will be expanded to the east and gadually raised in height. Map C-3 shows the <br />cross sections of the existing and the expanded waste rock embanlQnent. The waste rock will be <br />hauled to the pile by low-profile trucks or "buggies" and dumped neaz the edge of the pile. A dozer <br />will then level and push the material over the edge of the pile. The pile will have two levels; the <br />lower level at the portal and an upper level to the east that will gradually increase in height and <br />move further to the east as more waste is placed. Travel over the pile by the loaded rubber-tired <br />buggies will compact the material creating aloes-permeable surface. The waste rock pile will have a <br />capacity of 900,000 tons, which will contain most of the waste rock generated during the projected <br />ten-year mine life. The remaining waste rock will be disposed of underground in mined out azeas. <br />The azea east of the existing waste rock pile wnsists of pinyon and sagebrush crisscrossed by <br />historic drill roads and pads (see Map C-lA). Prior to expansion of the waste rock embankment to <br />the east, the vegetation will be stripped and approximately 12 to 18 inches of topsoil will be <br />removed and stockpiled in Stockpile #1 shown on Map C-2 on the north side of County Road 5/10. <br />Another small stockpile azea exists on the expanded bench (Stockpile #3). Downed trees will be <br />placed in a sepazate pile that will be made available for firewood collection The azea around the <br />Whirlwind and Packrat portals has been checked for springs and seeps. None exist within the azea <br />of the waste rock embankment expansion. <br />The waste material will be generated from above and below the ore-bearing material by blasting <br />(i.e., split-shooting). The material will be primarily sandstone that loses a lazge portion of its <br />cementation upon exposure to air and water. The blasted rock ranges in size from fine-grained sand <br />particles to a maximum of 2 feet in diameter. As the waste rock is brought outside in the buggies, it <br />.) <br />Whirlwind Mine June 07 D-10 <br />