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Geotechnical Stability Exhibit <br />Exhibit 6.5 <br />Wildcat Mining Corporation <br />May Day Idaho Mine Complex — 112d Permit Application <br />Revised August 2011 <br />Geotechnical Stability Exhibit 6.5 <br />calculation. A hypothetical slip surface that extends into the roadway (and thus would be <br />impacted by a surcharge load) would also extend into rock. <br />To evaluate the impact of a surcharge load, Wildcat reviewed the stability analysis performed by <br />Sakura Engineering, dated November 8, 2008. Its analysis of the road cut yields a factor of <br />safety of 1.54 (Sheet 4), well above the minimum desirable factor of safety of 1.3 for roadways. <br />Considering the impact on stability of a 25 ton equipment load, Mr. Rauber assumed a static 25 <br />ton surcharge acting uniformly over the outboard 10 feet the road and for 10 feet along the <br />alignment. Mr. Rauber conservatively increased the driving force by 25 tons while not <br />increasing the resisting force. This drops the factor of safety from 1.54 to about 1.46, still well <br />above a factor of safety of 1.3 considered adequate for the roadway. Considering the load is not <br />static and not acting uniformly over the area described, provided the roadway surface is prepared <br />as described in the construction activities work plan, and wheel loads are at least 2 feet away <br />from the outboard slope, this factor of safety is considered to be conservative. The above <br />statements will be confirmed upon the conclusion of the access road geotechnical investigation. <br />(See Boring Locations, Figure 6.5 -3) <br />In addition, recommendations resulting from a geotechnical evaluation of access road stability <br />performed in May, 2010 have been incorporated by reference into the road construction work <br />plan including the recommendations offered by Mr. Allen Sorenson in his memoranda dated <br />October 28, 2009, and May 17, June 4 and June 7, 2010. The road construction work plan <br />includes the following design and construction activities: <br />• Construct the road using the design and BMPs (Attachment D- 1); <br />• Installation of construction and permanent erosion and sedimentation BMP controls <br />including: <br />o Wattles, silt fences (where feasible); <br />o Debris /catch basins; <br />o Culverts ; <br />o Rock berms; and <br />o Ditches. <br />• Installing grade stakes; <br />• Clearing cut slopes and store trees and scrubs in designated staging areas and ultimately <br />chip for reclamation, use for fire wood or remove and dispose in a landfill; <br />• Removing existing road fill through a series of benches (fill on existing slopes beyond the <br />roadway fill will be removed as part of the construction of the access road). In the <br />roadway footprint between the underlying stiff natural soils or rock and roadway <br />subgrade. It includes "out slope fill ", but only in the zone between the underlying natural <br />soil /rock and the roadway subgrade; <br />• Placing road fill and material from cut slopes in designated staging areas or in areas to <br />achieve base of operation or final road grade; <br />• Monitoring, documenting and testing road grade and cut and fill activities; <br />• Analyze road construction materials per ASTM standards and criteria; <br />• Grade road to drain to the inboard road cut per specifications; <br />Page 5of <br />