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14.5 Designated Chemical(s) Evaluation <br />The designated chemicals include sodium cyanide and dilute sodium cyanide solutions, sodium <br />hydroxide, hydrochloric acid, potassium amyl xanthate, dithiophosphate, and frother. Table 14 -2 <br />above shows the expected quantities in storage and in solution for the designated chemicals, <br />expected concentrations for the dilute sodium cyanide solutions used in processing for ore <br />beneficiation, and the fate of the designated chemicals. <br />Material Safety Data Sheets for designated chemicals are included in Appendix 10, Volume VI <br />of this document. <br />14.6 Designated Chemical(s) and Material(s) Handling <br />The use, disposal, and detoxification of designated chemicals for ore beneficiation are described <br />in Sections 6.0, 7.0, 8.0, and 12.0 of the Project Description. CC &V has documented the <br />containment of all currently used designated chemicals in theSPCC, which is included as <br />Appendix 14, Volume VII. If approved, additional designated chemicals for MLE2 will be <br />included in an updated SPCC Plan. All areas where designated chemicals are used or stored <br />have a minimum of primary storage and secondary containment to prevent materials from <br />entering stream channels, escaping into areas subject to storm water runoff, or migrating offsite. <br />The concrete containment for the ADRs are graded to drain to the VLFs. Below each concrete <br />containment is a synthetic liner, which is also placed to drain to the respective VLFs. MLE2 <br />proposes to tie in the lining system from the High Grade Mill facilities platform into the SGVLF <br />lining system upon completion of SGVLF construction. Additionally, the concrete foundation of <br />the High Grade Mill facilities will serve as containment. These engineered features are <br />buttressed by good housekeeping protocols, preventative maintenance, best management <br />practices to prevent spills, safe handling and material transfer practices, and regular visual <br />inspections of containment structures. <br />Final closure of the VLFs will include double rinsing of the ore with recirculated solution from <br />the VLFs, and assuming additional sodium cyanide destruction is needed after these two rinsing <br />cycles, it is proposed this will be followed by hydrogen peroxide- assisted rinsing cycle to <br />complete removal of sodium cyanide, per the discussions in Section 12.0. Final closure will <br />occur over an approximate five- to six -year period for each VLF. As a result of recirculation and <br />rinsing, associated process equipment will be rinsed and rendered suitable for demolition and <br />salvage. The MLRB has approved a standard of an average concentration of CNWAD less than <br />0.2 mg /L in the rinsate or in results from meteoric water mobility testing of the neutralized ore <br />material. Once data supporting this standard has been collected, CC &V will provide this <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />14 -10 <br />