Laserfiche WebLink
containment. The dithiophosphate will get carried with the floated material into the leach circuit <br />where it will be destroyed by the addition of lime and dilute sodium cyanide solution. <br />Frother — The frother is a long chain alcohol which will be used to form stable air bubbles for <br />floating of the gold material in the flotation circuit. The frother will be shipped as a liquid in <br />totes. Approximately four shipments will occur per year with 20 totes per shipment. The totes <br />will be stored inside the mill building to prevent freezing. Since storage will be inside the mill <br />building, the concrete flooring and curbing will provide secondary containment. The frother is <br />recycled with the water from the flotation circuit, eventually breaking down into non toxic forms. <br />Sodium Cyanide — A dilute sodium cyanide solution will be introduced into the mill process at <br />the cyanidation leach tanks. Sodium cyanide will be delivered to the site by truck in U.S. <br />Department of Transportation ( "USDOT ") approved containers. The sodium cyanide will be <br />delivered as solid briquettes. The shipping containers will be unloaded on a concrete apron west <br />of the tanks. The concrete apron is curbed and graded to drain to a sump in the event of a spill or <br />leak during unloading. A basic water solution will be pumped through the container to dissolve <br />the briquettes. The dissolved solution will be stored in tanks located on the cyanidation leach <br />tank concrete foundation. <br />The cyanidation tanks will be located on the west side of the mill building within a concrete <br />foundation with curbing. The top of these tanks will be open and bird mitigation measures such <br />as netting or bird balls will be implemented, if necessary. Past experience with dilute sodium <br />cyanide solution leach tanks has shown that birds do not tend to use these as a water source due <br />to the small open area of each tank, the noise associated with the agitation, and the level of <br />activity of the milling operations. Leaks or spills from the cyanidation leach tanks will be <br />contained within the curbed concrete foundation for the tanks. <br />6.5 Water Balance and Recycling <br />The High Grade Mill facilities will recycle water to the extent possible, adding makeup water as <br />necessary to maintain the appropriate slurry densities within each mill circuit. There will be two <br />separate mill water circuits: one for mill water which does not contain sodium cyanide and one <br />for the mill water containing dilute sodium cyanide solutions. These two circuits will be operated <br />as separate closed circuits as far as water addition and recycling is concerned to limit the areas <br />where sodium cyanide is present in the milling process. <br />The flow rate for the grinding and flotation portions of the High Grade Mill facilities will be <br />approximately 2,720 gpm (850 tons of slurry per hour). The flow rate for the leaching and CIP <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />6 -12 <br />