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M1994-117, TR-05, T.Waldron January 27, 2009 2 of 3 <br />3) Per MLRB Rules, 1.1.12: "An ...Operator who intends to mill ores from other <br />mining operations must submit adequate information to demonstrate that waste <br />(material or stream) from such ores will be processed or disposed of in a manner <br />to protect human health, property and the environment". Material (ores) <br />processed from the Cross Mine will generally be analogous to the currently <br />processed Cash & Who Do Mine ores. This is demonstrated in the following <br />table (Table 7.1 - Ore Comparison). Tailings from these materials post- <br />processing are compared below (Table 7.2 - SPLP & TCLP Comparison). <br />4) As the DRMS is aware, MRV emplaces mill tailings in either the permitted, <br />double lined pond adjacent to the Gold Hill Mill, or in the Cash & Who Do Mines <br />and associated areas pursuant to EPA UIC-Class V Permit (By Rule), File <br />#C050000-08061. With the exception of barium (Ba) and lead (Pb), the TCLP <br />data reflect close similarity in tails composition. With Ba at only twice the <br />content of the Cash Mine ores and still considerably below the MCL of 100 mg/1 <br />(EPA HW Code D005), Pb is the only regulated inorganic substance above the <br />MCL (EPA HW Code D008). Calais Resources, Inc. (Calais), operator of the <br />Cross Mine has provided data for tails from processing using one specific reagent <br />set, but has indicated that the reagents in use at the Gold Hill Mill (Cytec AF 68 <br />and/or Pine Oil, Sodium Isopropyl Xanthate, Soda Ash) will significantly lower <br />the Pb contained in the process tails. MRV concurs with this assertion, noting <br />that MRV utilizes a less selective bulk sulphide flotation than that used to create <br />the tails analyzed by RDI (2008), which will significantly increase the Pb <br />reporting to concentrate rather than tails. In addition, MRV posits that the acidic <br />(low pH) conditions necessary to leach the lead from the tailings material do not <br />exist, as both the process water and paste pH from the proposed milling will be <br />basic. Noting the SPLP data, Pb content of the tailings from the Cross ores will <br />be significantly below the MCL (0.01-0.0124 mg/L). MRV and Calais agree that <br />laboratory analysis will be performed on the tails material generated, further <br />documenting this. The DRMS should note the availability of carbonates and the <br />basic nature of the Cross Mine ore as presented in the attached data as support for <br />this assertion. <br />MRV includes by reference, "Cash Mine Non-Designated Mining Operation <br />Certification, Permit M-1983-141", Date: December 10, 2006 previously <br />submitted to the DRMS under TR-05 to the M1983-141 Reclamation permit. <br />5) Current permit capacity at the site is 70,000 tons per annum. MRV proposes to <br />begin adding the Cross Mine material to the processing at the Gold Hill Mill at <br />the rate of 50 tons per day, with the goal of processing a combined total of 200 <br />tons per day (in accordance with the existing permit limit of 70,000 tons per <br />annum) achieved upon successful testing of the additional material. <br />M1994-117 TR07 1-30-09.docx