2011-10-20_REVISION - M1981185 (10)

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Mr. Wallace H. Erickson Supplemental Response to Fifth and Sixth Adequacy October 20, 2011 Page 8 structures. In addition, a third copy of a damage compensation agreement for the May Day Idaho Mine Complex was sent on May 23, 2011 to all individuals who are within 200 feet of the permit boundary. As to these individuals, Wildcat submits the following engineering evaluation demonstrating that man made structures owned by these individuals within 200 feet of the permit boundary shall not be damaged by activities occurring at the mining operation. Wildcat has previously conducted field surveys of affected lands within 200 feet and has determined there will be no impacts the adjacent structures. See Exhibit 6.5, at 9 -10. Structures include fences, domestic wells, and well head protection sheds. Engineering assessment included simulating potential slope failure impacts to manmade structures, and the possibility of well production losses due to compaction/siltation from the adjacent access road. For instance, Wildcat calculated in its Geotechnical Stability Exhibit, which was certified by Mr. Erich Rauber, P.E., that: "The private owner property boundary is approximately 80 feet from the New Access Road cut slope and if the road cut failed (which is highly unlikely) where a final 3:1 slope was created, the land slide head cut would be approximately 40 to 45 feet from the private landowner's property boundary. Recent geotechnical assessments described in Attachment 6.5.3 and Attachment D -1 suggest that the current and final cut slopes are stable." See Exhibit 6.5, at 10. With regard to landowners with wells, including but the Linden, Fagerlin and O'Donnell wells, the access road is offset is at least 25 feet from the adjacent landowners well head where water is produced from the La Plata River shallow alluvium. The depths of the wells adjacent to the access road range from 8 to 15 feet deep. The alluvium consists of large cobbles, sands and silts. The road bed will be constructed such that drainage and possible siltation will be diverted away from the adjacent wells. The road bed will consist of cobbles and coarse gravels (highly permeable) which has the capability of conveying water through the subgrade road base (in the event of flooding) thus allowing water to recharge to the alluvium and to the adjacent wells. Using case studies similar to the Wildcat Mining Corporation, the La Plata River hydrogeologic characteristics related to porosity, permeability, water levels, well yields, or aquifer flow rates were not be affected by road construction or operation. Wildcat has also conducted engineering evaluations of potential impacts to off site man made structures from blasting activities. See Exhibit 6.5, at 10 -11. Mr. Terry Morris, P.E., calculated the amount of explosives which could be detonated with no expected off site structural damage using the industry standard scaled distance approach. Id. & Attachment 6.5.4. Mr. Morris determined that 1,100 pounds of explosive could be detonated with no expected structural damage, and that the 100 pounds proposed by Wildcat underground at the May Day No. 2 would also cause no structural damage. Id. The affected access adjacent to the road area will be immediately revegetated and stabilized after construction while the installed drainage structures will be constructed to direct any potential sediment from the road surface. The road will be primarily used by DEN 97,637,083v1 10 -20 -11 GREENBERG TRAURIG, LLP ® ATTORNEYS AT LAW ® WWW.GTLAW.COM