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<br />Venture Resources, Inc. <br />P(_) Box 1974 003) 619-6323 <br />Idalto Springs, CC) 80452 Fax: (1303) 484-6369 <br />vetutttreresottrces(a•atta iet <br />November 2, 2010 <br />CO Division of Reclamation, Mining & Safety <br />1313 Sherman St., Room 215 <br />/Denver, CO 80203 <br />Attn: Jared Ebert <br />RE: M-2009-076 Application <br />Subject: ResponDRMS November 0 email regarding Tailings Impoundment Stability <br />Dear Mr. Ebert: <br />RECEIVED <br />-?,- 60V 0 4 2010 <br />r) Divis un u; M'6u«allatmn, <br />Wing and OW*j <br />Venture Resources is in receipt of your email dated November I' detailing the DRMS response following your site <br />visit (inspection) and in answer to the proposed engineering solutions we offered to increase our tailings <br />impoundment's stability. <br />Quite frankly, we are extremely disappointed by the DRMS response, since we proposed significant stability <br />enhancement in order to satisfy the DRMS concerns related to tailings stability. It appears that the targets have been <br />moved once again for us. Random requirements and arbitrary conditions are again being asked of us that are not <br />found in the statutes or Hard Rock Rules. <br />In your email you stated: <br />"Geotechnical stability tests will need to be done for the tailings embankment under un-saturated <br />conditions and the factors of safety must meet/exceed the Divisions requirements of 1.1 for seismic <br />conditions and 1.5 for static conditions." [emphasis added] <br />We have been preparing a revised design/technical revision and have proposed an engineering solution based on the <br />September 8'h DRMS Second Adequacy Review. In that Review, we were directed to provide for a saturated slimes <br />factor of safety target of 1.5 for static and 1.1 for seismic conditions. The Synteen Technical Fabrics engineering <br />analysis that we provided during your site visit demonstrates the proposed design using Synteen Technical Fabrics <br />exceed the required 1.5 for static conditions and 1.1-for- seismic loading for all incremental phases, except for one lift <br />in Bench #3. <br />Please clarify the DRMS position for targets of factor of safety: saturated or un-saturated conditions? It appears the <br />factors of safety are of DRMS' own choosing since there is no mention of specific values of factors of safety in the <br />Hardrock Rules. For future reference, we would appreciate knowing how these factors were chosen. If they are <br />based on DRMS policy, please provide Venture Resources a copy of such policy. If they are based on an engineering <br />reference, please provide the reference cite. <br />Requiring this design to be evaluated at 100% saturated water levels at total buildout does not conform to real or <br />practical considerations. Our professional knowledge and experience (Venture Resources' staff has two Certified <br />Professional Engineers and a Certified Professional Geologist) tells us that the tailings will dewater, dry and <br />consolidate and that the impoundment stability only increases over the long term. Carefully adhering to the <br />operating and embankment construction parameters set forth in Exhibit C of our last technical revision ensures <br />proper impoundment stability behavior. These parameters prescribe a method of tailings impoundment, dewatering <br />practices and embankment geometry relationships. The design was developed based on the preeminent works on this <br />Pagel of 3