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<br />Along with the other revisions to MDI's conversion application that will be submitted, <br />MDI will submit an addition to Phase I which will include a specific plan for detoxifying <br />the material in the leach pad. This as you may recall was discussed at the mine site <br />during MDI's last inspection on 11!1/95. Briefly, our plan involves removing the material <br />from the pad and placing it on high ground, replacing the liner, then screening the <br />material that was placed on high ground through the flotation mill. All tails from this <br />portion of the process will he given a peroxide wash to neutralize the cyanide. Subject <br />to the Divisions approval, MDI will take a representative sample periodically from this <br />portion of the process and have it tested for cyanide to prove the effectiveness of this <br />method. <br />2. Please provide a detailed schematic diagram of the milling facilities with <br />volumes and proposed maximum rates of processing through the system, <br />concentrations of the contents of each container in the process, where in the <br />process that each chemical is added and at what concentration, and the mode of <br />transport from each phase to the next. The location of the chemical storage area <br />should also be indicated with a description of how the chemicals will be kept dry. <br />Attached with this letter you will find Appendix 1 which is a schematic diagram for the <br />flotation process. The volumes and proposed maximum rates of processing are written <br />on the schematic. The flotation circuit proposed has a maximum rated capacity of 50 <br />tons/day. MDI's days, however, will be 12 hours long, so we will only be able to put 25 <br />tons/day through the mill. Furthermore, MDI will spend half the week breaking ore, and <br />the other half processing the broken ore. This leaves us with an approximate maximum <br />rate of processing of 12.5 tons/day. Only three chemicals will be required for the <br />flotation circuit; they are potassium amyl xanthate, sodium hydroxide, and pine oil. The <br />exact location in the process where these chemicals are added will be labeled on the <br />schematic also. We have designated a chemical storage area adjacent to the process <br />on the concrete pad. This area will be kept dry by placing a roof across the walls. <br />3. Please confirm whether or not the proposed production rate will allow <br />processing of the existing ore, on site and above ground, within 180 days. If the <br />ore stockpile cannot be processed and thereby removed from the site within 180 <br />days, please provide analysis documentation that proves this material is not <br />potentially acid and/or toxic producing. Be aware that if the stockpiled ore <br />proves to be potentially toxic or acid forming, and is not or will not be processed <br />within 180 days, the Neglected site will be designated as a DMO. <br />What MDI is considering existing ore is actually waste rock from previous milling <br />operations. It has been present on the surtace for more than 10 years and MDI has <br />reason to believe that it is not acid and/or toxic producing. In support of this MDI has <br />taken a representative sample from this pile and had an accelerated <br />weathering/leaching test performed. These results are included as Appendix 2. Since <br />much of the first seasons operation will be dedicated to mobilizing the equipment, and <br />