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Additionally, all process water and leachate is reclaimed/recycled by the means of a pontoon mounted pump or <br />sump pump from the impoundment to the Mobile Mill Site Water Holding Pond. <br />Due to the remote nature of the disposal site location, visual nuisance impact to the public is minimal if not non- <br />existent. The site cannot be seen from any public roadways. The waste has no adverse odor. Because the waste <br />stream is water carried, there is very limited noise pollution as heavy equipment is only needed during maintenance <br />procedures and for placement of cover materials and re-vegetation. <br />6.3.3(1)(1) <br />Please refer to 633(1)(i), 6.33(l) j), and Exhibit D for a detailed explanation of how this operation will minimize <br />disturbance to the hydrologic balance, prevent off-site damage, and provide a stable configuration of the reclaimed <br />area. <br />6.3.3(l)(m) <br />There will be mineral processing conducted on-site within the area designated Mobile Mill Site. <br />Mine waste rock dumps and/or ore are subjected to processing by gravity & flotation separation to remove the <br />pyrites (FeS2)/chalcopyrites (CuFeS2)(sulfide minerals), gold, silver, lead, zinc, copper, and other trace heavy metals <br />that associate with the sulfides (the acid producing materials). Lime and/or soda ash is added to adjust pH to 7.5-9 <br />to precipitate metal salts as insoluble hydroxides and/or carbonates and for corrosion control (reference A Water <br />Handbook for Metal Mining Operations, by Thomas R. Wildeman for a detailed explanation of the chemistry <br />relative to this process). <br />Waste produced is inorganic, consisting of silica & alumino silicate minerals, which are inert and meet SPLP <br />standards for RCRA metals as shown in the attached lab results for waste stream characterization. The waste rock <br />has been finely ground and resembles sand and clay. The toxic sulfides have been removed during the milling <br />• process. The sand portion is composed of vein type material such as quartz gangue and quartz monzonite porphyries <br />with some of the surrounding wall rock composed of metamorphic gneisses. The clays are formed from altered wall <br />rock and feldspars. This waste is water carried via pipeline to a settling impoundment. There is zero water <br />discharge and the water is nearly 100% recycled back to the mill as process water. <br />Processing can be described as follows: <br />1. Dump truck and/or loader arrive at the Mobile Mill Site and unload into Crusher Feed Pile next to the <br />crushing plant. <br />a. This pile is a short-term stock pile that will have stormwater management measures in place to <br />control the potential of any acid run-off. <br />2. A loader will begin feeding the Crusher Feed Bin that feeds a jaw crusher. This jaw crusher will reduce <br />any larger rock to +/- 1.0". <br />3. Once through the jaw crusher, the material is feed to a roll crusher which further reduces the material to +/- <br />1/8". This two-stage crushing operation is a dry operation and the crushed material is collected in a <br />weather-tite Crushed Rock Bin, containing approximately 80 tons. <br />4. The crushed material is then feed to a ball mill. <br />a. Here we begin to add water and lime to control the pH. Water is added at a rate to achieve +/- <br />601/o - 701/o solids by weight "ore". Ball mill solution volume is approx. 15 cu. ft. <br />b. The rotating action of this cylindrical mill with a charge of round steel balls produces a grinding <br />process. <br />c. The raw dump material is capable of showing a pH of 3.5, highly acidic. <br />d. We add several pounds of lime to each ton of material to bring the pH to 7.5-9. It is practically <br />chemically impossible to have heavy metals in solution when the pH is basic. Adding the lime <br />precipitates the heavy metal contaminants. <br />e. An electronic pH monitor and controller is used to maintain a consistent rate. <br />5. The finely ground (+/- 60-100 mesh) slurry is then delivered to a concentrating ("shaker") table. Here is <br />where the specific gravity separation of the heavy metals and any trace precious metals takes place. There <br />are four zones on the table where a product is delivered: <br />. a. Slimes zone - discharge is collected and sent to the flotation circuits for further treatment. <br />b. Sand zone - discharge is devoid of any mineralization, cleaned sands sent to tailings. <br />8