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• 3. Releases durin>; unloading cyanide <br />Potential releases during cyanide unloading are possible but are minimized through design of the <br />:off loading facility including a curbed concrete containment pad provided for truck parking, <br />containment for the off load piping and tankage, and synthetic liner underlying these facilities <br />and immediately adjacent areas. Additionally, the synthetic liner is tied into the VLF for <br />containment purposes. Facility design also includes appropriate interlocks for valves and piping. <br />Specific off loading procedures are written and followed. Should a release occur it would 1) be' <br />within secondary containment or 2) if it exceeded containment;. the surrounding area is relatively <br />flat, and there are additional pond structures downgradient of the off loading facility that would <br />function as unlined containment structures to minimize or eliminate a release to streams or <br />offsite, but not preventing release to soils. <br />4. Releases during mixin of cyanide ' <br />Potential releases during mixing of cyanide are possible but minimized through implementation; <br />of procedures and by facility design. Mixing of cyanide occurs during the off loading process as <br />alkaline- solution is circulated through the dry product in the delivery truck and the resulting <br />solution is pumped to storage tanks within secondary containment. Written procedures. are in <br />place and followed for cyanide off loading and mixing. Controls are in place to assure that the <br />mixing solution is of appropriate alkaline pH (pH of 10.0 or greater). Mixing occurs on and <br />within the containment areas described under the "Releases during unloading cyanide" section <br />above. <br />• 5. Releases due to fires and/or explosions in the process plant '; <br />Risk of fire in the ADR facility is minimal but could possibly occur due to maintenance activities <br />.such as welding or electrical fires. The ADR is equipped with fire suppression systems in the <br />Motor Control Center areas and portable fire extinguishers are placed throughout the facility in <br />appropriate locations. Such fire suppression systems are routinely inspected, thus assuring proper <br />function should a fire occur. If a fire were to occur, it is unlikely that it would be catastrophic, i <br />resulting in the release of cyanide solution, but would likely be confined to a particular section of <br />the facility. The ADR -has a concrete floor, metal exterior sides, and contains primarily steel <br />piping and vessels. The presence of combustible materials is minimized. In addition to on site <br />fire suppression capabilities, including large water trucks, a fire response agreement is in place <br />with Cripple Creek to provide additional resources if needed. Moreover, the ADR facility is tied <br />to the VLF thus any flow from the fire suppression system would be to containment. <br />6. Ruptures or leaks in Wipes, valves, and/or tanks containin;? cvanide solution <br />Rupture or leaks in pipes, valves, and/or tanks containing cyanide solution is possible but would; <br />likely be contained by facility design. The ADR is designed for solution containment through <br />floor gradients, curbing, passive overflow outlets to the VLF, and by the underlying liner <br />attached to the foundation perimeter. Further, containment liner and routing of released solution <br />to the VLF for external tankage spillage is in place on the VLF side of the ADR and has been <br />tested at significant flows. Handling of overflows within the ADR is largely handled passively <br />through gravity drainage to the VLF, except for pumping of the lined area beneath the concrete <br />floor. <br />• Cyanide Emergency Response Plan September 25, 2006 <br />EMS: AGANA/CCV Doc.# E-012 <br />S:\4010-00055 CC & V l 12(d) Permit Application\ERP, SPCC, FMP\Cyanide Emergency Response Plan.doc Revision 03 <br />-4- <br />