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Comment 4: Please demonstrate how TR-81 addresses enhancements to the capacity of <br /> the secondary containment as required by the Corrective Actions of Violation MV-2016- <br /> 03. The Technical Revision contains information regarding the liner under the High <br /> Grade Mill (HGM), which serves as tertiary containment. Beginning in December of <br /> 2015, the Division observed seeps near the southwest corner of the HGMplatform, <br /> originating at the edge of this tertiary containment. On May 23, 2016, CC&V clarified <br /> that the capacity of this liner had been consumed and overtopped as a result of the HGM <br /> fire suppression lines. Evidence that the apparent 16.8 million gallon capacity of this <br /> liner had been consumed, reinforces the requirements of the Board Order of Violation <br /> MV-2016-035. <br /> Response 4: CC&V will continue to rely on the tertiary liner containment as capacity <br /> for potential upset conditions. It is supported by pumps which maintain very low water <br /> levels of the sump area,thus maintaining adequate capacity. CC&V would like to <br /> clarify that while the capacity was "consumed"once,the capacity has since been <br /> reestablished and maintained through pumping to control meteoric precipitation <br /> infiltration <br /> Comment 5: TR-81 states the secondary containment will hold 75%of one vat leach tank. <br /> Please provide as-constructed diagrams of the vat leach facility to verify this volume. <br /> Response 5: CC&V has enclosed engineered drawings and calculations in support of <br /> a planned improvement which would increase secondary containment to 110% of <br /> the volume of one leach tank. CC&V also plans to elevate electrical and pumps in <br /> line with the secondary containment enhancement.Please see the enclosure <br /> documents: <br /> 1) Structural Calculations for the Leach Tank Secondary Containment; and <br /> 2) Secondary Containment Drawings. <br /> Comment 6:Please provide the volume of the precipitation captured by the tank battery <br /> and secondary containment during a 100 year/24 hour storm. <br /> Response 6: A 100-year/24 hour storm event is considered 3.5 inches of <br /> precipitation. <br /> During the assumed storm event, the volume of precipitation captured by one leach <br /> tank will be 192 cubic feet(ft) or 1,436 gallons,for six leach tanks the volume will <br /> be 1,152 W or 8,618 gallons. <br /> The secondary containment will capture 3,337 W or 24,962 gallons. <br /> In total,the primary and secondary containment will capture 33,578 gallons during <br /> a 100-year/24 hour storm event. <br /> Comment 7: Please provide the maximum flow rates of the process slurry entering the leach <br /> circuit. <br /> Response 7: Assuming throughput increase to the full nameplate tonnage,the <br /> maximum flow rates of the process slurry is 150 gallons per minute(gpm). <br />