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4- <br />Venture Resources, Inc. <br />PO Box 1974 (303) 619-6323 <br />Iclaho Springs, CO 8o452 Fax: (303) 484-6369 <br />ventureresources(matt.uet <br />October 1, 2010 <br />CO Division of Reclamation, Mining & Safety <br />l?lVl:,?n Q, ?? <br />1313 Sherman St., Room 215??IF?^tItQf1, <br />Denver, CO 80203'??'' z ri' <br />Attn: Jared Ebert <br />RE: M-2009-076 Application, Second Adequacy Review Response #2 <br />Subject: Acceptable Impoundment Outslope Angle C-*"!' <br />Dear Mr. Ebert: <br />As we discussed in yesterday's meeting, we would like to learn from the DRMS what impoundment outslope angle <br />will be acceptable (considering stability and revegetation issues) for approval regarding this project. This should be <br />based on the method of hydraulic placement, geotechnical and the proposed impoundment location information <br />which we have thus far submitted. Please also recall that we all reached a level of understanding, supported by third <br />party laboratory liner interface friction testing in our latest submittal, that the foundation grade angle is not a <br />limiting factor (see Sept. 8`h Second Adequacy Review page #I item #3 for DRMS acknowledgement of the same). <br />It is our desire to apply this acceptable outslope angle to all five proposed benches, but we would consider accepting <br />approval through completion of proposed Bench #2 (to match the incremental reclamation plan so far submitted). <br />This is in response to a tentative DRMS rejection of our proposed impoundment outslope angle of 1.5H:1V. The <br />DRMS has suggested varying factors of safety for varying conditions, thus we have found it difficult to prepare an <br />acceptable design. We understand that the DRMS uses a software tool (Clover Associates Galena) for "verification <br />purposes" and relies upon it when considering impoundment stability. We are not familiar with this tool and find it <br />difficult to defend our design against the data Galena produces. <br />Having this acceptable outslope angle information will allow us to make the necessary business decisions on <br />whether or not to proceed to completion with this permit application. Changing this angle will impact the volume of <br />tailings which can be impounded in this proposed location. Venture Resources wishes to thank the DRMS for <br />looking into this. <br />Sincerely, <br />Venture Resources, Inc. <br />Ryan J. McHale, PE <br />Vice President <br />k VE <br />0"r 0 5 2010 <br /> <br />Page 1 of 1