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• 5. Waste Rock Embankment <br />The existing bench at the Whirlwind portal was made from waste rock excavated from the driving of <br />the decline and the two short developmental drifts at the base of the decline. The slope of this bench <br />was reclaimed previously but will be re-disturbed since the bench will be expanded using waste rock <br />produced from underground mining operations. See Map C-lA for the configuration of the current <br />bench. See Map C-2 for the plan view of the expanded waste rock embankment. <br />The waste rock pile will be expanded to the east and gradually raised in height. Map C-3 shows the <br />cross sections of the existing and the expanded waste rock embankment. The waste rock will be hauled <br />to the pile by low-profile trucks or "buggies" and dumped near the edge of the pile. A dozer will then <br />level and push the material over the edge of the pile. The pile will have two levels; the lower level at <br />the portal and an upper level to the east that will gradually increase in height and move further to the <br />east as more waste is placed. Travel over the pile by the loaded rubber-tired buggies will compact the <br />material creating aloes-permeable surface. The waste rock pile will have a capacity of 900,000 tons, <br />• which will contain most of the waste rock generated during the projected ten-year mine life. The <br />remaining waste rock will be disposed of underground in mined out areas. <br />The area east of the existing waste rock pile consists of pinyon and sagebrush crisscrossed by historic <br />drill roads and pads (see Map C-lA). Prior to expansion of the waste rock embankment to the east, the <br />vegetation will be stripped and approximately 12 to 18 inches of topsoil will be removed and <br />stockpiled in Stockpile #1 shown on Map C-2 on the north side of County Road 5/10. Another small <br />stockpile area exists on the expanded bench (Temporary Topsoil Stockpile). Downed trees and all <br />other woody material will be placed in separate piles that will be placed on top of the topsoil during <br />reclamation, either as mulch or in whole pieces. The area around the Whirlwind and Packrat portals <br />has been checked for springs and seeps. None exist within the area of the waste rock embankment <br />expansion. <br />The waste material will be generated from above and below the ore-bearing material by blasting (i.e., <br />split-shooting). The material will be primarily sandstone that loses a large portion of its cementation <br />• upon exposure to air and water. The blasted rock ranges in size from fine-grained sand particles to a <br />Whirlwind Mine 07 (rev. April 08) D-11 <br />