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.. .: <br />-z- <br />8. The operator will monitor the groundwater monitoring wells in Wilson Gulch in addition to <br />the ones in Arequa Gulch on a monthly basis and provide the complete suite analysis on <br />a quarterly basis. The analysis will include cyanide (WAD) and free cyanide. <br />9. If free or WAD cyanide is detected in the effluent from the Arequa Gulch underdrain, or in <br />any of the monitoring wells surrounding the heap leach, the Office will conclude that heap <br />leach containment has been lost. If free or WAD cyanide-contaminated effluent enters the <br />leak detection system trenches and sumps at a rate exceeding one (1) gpd per acre, the <br />Office will conclude that heap leach containment has been lost. The operator shall notify <br />the Office within 24 hours in the event of any of these occurrences. Further, the operator <br />shall immediately cease application of leaching solution to the heap leach and initiate <br />detoxification within one week. Detoxification shall continue until an acceptable remedy <br />has been approved by the OMLR and implemented by the permittee. All fluid volumes <br />collected from the leak detection sumps shall be inventoried by sump weekly and reported <br />to the OMLR in writing once a month. <br />All contaminated fluids (those fluids containing free or WAD Cyanide greater than baseline <br />concentrations or exceeding applicable water quality standards, whichever is less) from the <br />Arequa Gulch underdrain shall be collected, stored (not to exceed 60 days), detoxified and <br />released. Under no circumstance shall any of this contaminated effluent be introduced into <br />the heap leach. The permittee shall develop a plan for the collection, storage, detoxification <br />and disposal of all fluids collected from the Arequa Gulch underdrain. No leaching solution <br />shall be applied to the heap leach facility until this plan has been approved by the Office. <br />10. Contaminated fluids from the leak detection system trenches and sumps shall be disposed <br />of as follows. Up to ten gallons per minute of effluent collected from the leak detection <br />system may be introduced into the heap leach solution circuit. Contaminated fluids <br />collected from the leak detection system in excess of ten gallons per minute shall be <br />collected, stored (not to exceed 60 days), detoxified and released, in accordance with the <br />plan for contaminated fluids from the Arequa Gulch underdrain. All fluids introduced from <br />the leak detection system into the heap leach solution circuit shall be inventoried using <br />appropriate metering and recording procedures. The fluid volume introduced into the heap <br />leach shall be reported to the Office in writing once a month. The permittee shall develop <br />a plan to adjust the heap leach fluid inventory (water balance) so as to maintain the <br />saturated level below the 80 percent level. No contaminated fluid collected from the leak <br />detection system over and above the calculated rate of 1.0 gpd per acre shall be introduced <br />into the heap leach until this plan has been approved by the Office. <br />t 1. In the event that any fluid is encountered in the leak detection system, the frequency of <br />monitoring in wells surrounding the heap leach shall be increased, at a frequency <br />acceptable to the Office. The permittee shall inform the Office within 24 hours following <br />the detection of fluid in the leak detection system. The permittee shall submit a plan for <br />increased monitoring to the Office within one week from the time the fluid is first detected. <br />12. The applicant will complete additional shear strength testing of the leach pad interfaces in <br />accordance with the recommendations of the Office and the third party reviewer. Subject <br />to the results of the additional testing, the applicant will submit design modifications and <br />