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As described earlier in 6.3.3(1)(h), water for the operations is obtained from the municipal water supply of the City <br />40 of Idaho Springs via a "Water Fill Station Usage Permit". There is the potential for rainwater to become co-mingled <br />with process water in the lined Tailings Impoundment and Water Storage Pond. Because no Industrial Discharge <br />Permit is in place, there are no provisions to treat this co-mingled water for release. To compensate for this, Venture <br />Resources will purchase a Temporary Substitution Water Plan contract from the Clear Creek County Water Bank. <br />A copy of this contract is provided as an appendix to this Exhibit C. <br />6.3.3(1)(k) <br />There will be NO designated chemicals used in this proposed operation. See a list of MSDS data at the end of this <br />exhibit for information on the chemicals to be used. <br />There will be, however, small scale handling of potentially acid forming material in the form of mine waste rock and <br />ore. There are carefully designed and managed measures in place to limit exposure and contamination. <br />To start, the Crushing Plant Feed pile is designed to contain any potential acidic runoff and/or seepage. A maximum <br />of 200 tons of material can be contained in this area for any period of time. The surface of this area is to be concrete <br />paved and sheltered with a roof to prevent any acidic run-off and potential seepage. Additionally, the surface slopes <br />i/4" - V towards the rear where a 10" wide x 48" high concrete wall provides a berm to contain any residual <br />moisture or sedimentation. The opened face of this structure shall be protected with a heavy canvas curtain that can <br />be closed during a rain/snow event. The surrounding grade will be sloped to ensure run-off will not enter the <br />structure. Construction and grading details can be found in Exhibit E, drawing E15 <br />The Crushing Plant operations are established to completely consume (on a daily basis) any material contained in <br />the Crusher Feed Bin to limit exposure. All of the crushed rock is stored in a Crushed Rock Bin. This bin can hold <br />80 tons of material. A removable roof covers the bin to keep the weather out and prevent any acidic runoff. <br />The gravity and flotation concentrate products that are collected and stored in Intermediate Bulk Shipping <br />• Containers which are palletized polyethylene containers surrounded by a steel skeleton framework for protection <br />from impact and crushing. These containers measure approximately 42" cubic. At any time there may be upto 30 of <br />these such containers stored on site, staged prior to transportation offsite. It shall be noted these containers meet <br />stringent DOT standards for transporting this specific material. <br />Within the proposed Tailings Impoundment there pre-exists approximately 8,000 tons of abandoned mine waste <br />rock. This operation will be removing this material and processing it to remove trace precious metal content as well <br />as heavy metal contamination. To mitigate any acidic runoff, best management practices within. the proposed <br />Tailings Impoundment will be conducted as follows (see more detailed SWMP in the appendix of this Exhibit C and <br />Exhibit E): <br />• Construct sedimentation basin. <br />• Construct riprap lined diversion ditches and connect natural diversion channels to sedimentation basin. <br />• Construct leachate collection barrier. <br />• Rip-rap and/or vegetate tailings dam face using appropriate controls, i.e. biodegradable netting and/or <br />hydro-mulch using specified NRCS seed mix (see Exhibit D). <br />Once processed, the cleaned tailings will be re-impounded in the Tailings Impoundment in a mostly inert state and <br />subjected to further reclamation as described in Exhibit D. Reference the attached waste stream characterization <br />demonstrating that the processed tailings are in a significantly better state than. existing conditions. <br />As a part of normal mill operations, mill process water will be continuously monitored. A pH monitor and data <br />recorder will be installed at the tailings pump location within the mill. Should the pH reach a state outside of the <br />7.5-9 range that is necessary to precipitate the heavy metals, alarm notification will be activated for the operations <br />personnel. The submittal notes on this Serfilco Model 432 monitor/recorder can be found attached in this Exhibit C. <br />If the pH falls outside of the 7.5-9 range, the operators are instructed to shut down the operation that delivers waste <br />to the impoundment. Once the source of the problem is corrected upstream in the process, waste can then be <br />• continued to be discharged to the impoundment. It is practically impossible for heavy metals to be in solution under <br />Page 8 of 35