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Access Portal Collapse Repair and Equipment and Stope Rock Removal Work Plan March 2, 2012 <br />May Day No. 1 <br />The collapsed material near the top of the respective portals will be removed to recover the <br />buried crushers and a mucker while stabilizing the Access Portal. Most of the estimated 2,300 <br />cubic yards of material can be removed from the area between the two portals utilizing an <br />excavator and a small front end loader, or using manual labor. The removed material will be <br />hauled to the May Day No. 2 bench (Figure 3) for temporary storage until Phase 2 when the <br />material will be used for stabilization of the highwall. The stored material will be surrounded <br />with erosion control devices such as silt fence, straw bales or straw wattles, and as appropriate <br />stabilized with straw mulch and tackifier. Straw materials will be certified weed -free. Crushers <br />will be removed from the collapsed mill area. No additional work will be conducted at the Mill <br />Portal other than removing the debris and soil within the mill building and removal of the <br />crushers and mucker. <br />Accessible trees, roots and loose vegetation in the collapsed material, and any generated <br />construction- related debris (wood, paper, etc.), will be removed and disposed in an approved off <br />site landfill. Wildcat will also scale rock, debris and vegetation from the highwall. <br />When the Access Portal has been cleared, a Colorado registered professional engineer will make <br />geotechnical and rock mechanics portal repair recommendations, including but not limited to <br />head scarp clearance, buttressing, rock bolting, and shotcrete stabilization coupled with steel set <br />portal installation and stabilization of the Access Portal. Any impaired steel sets will be removed <br />and stored in the Idaho warehouse. A steel protective shield or shields will be specified and <br />fabricated for the steel sets to provide protection of workers. <br />Interim portal rock stabilization methods will be installed as necessary to provide stability of the <br />rock mass for safe access. Based upon preliminary observations, these methods will include <br />installation of split -set rock bolts on spacing of 3 to 6 feet as necessary to stabilize the rock. <br />Galvanized steel straps may extend across rock joints between the rock bolts as necessary. <br />Chain -link or 4x4 wire mesh may be placed over rock surfaces, followed by at least 4 to 6 inches <br />of shotcrete. Conceptual sections of adit stabilization measures are presented on Figure 4. <br />Structural support systems are being designed by an engineer, but an example of what the design <br />may be is as follows: assuming a 10 -feet wide span and using a structural steel with a yield <br />strength of 36,000 pounds per square inch (psi), a W4x13 beam could support a uniform load of <br />8,600 pounds. If the spacing on the steel sets is 4 feet, and the assumed density of overlying fill <br />is 140 pounds per cubic foot (pcf), this would provide support for up to 15 feet of cover over the <br />adit. Final specifications for the steel sets will be dependent upon actual field conditions <br />encountered, and the height of fill over the adit prior to encountering sound rock cover. A <br />locking steel gate will be placed at the portal opening to control access to the adit. <br />Rehabilitation of the adit will be performed as necessary to access the stope area, including <br />mucking and rock stabilization measures. Wildcat will obtain representative samples of material <br />located at the stope area and conduct a geotechnical Z +F phase scan of the stope and portions of <br />EnviroGroup Limited <br />DEN 97, 749, 013v3 2 -29 -12 <br />5 <br />