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Musco Family Olive Comp - 2 - 4 May 2012 <br /> The LCRS test consisted of injecting a predetermined amount of water at about two gallons per <br /> minute into air vents in the primary liner and recording the amount of water that collected in <br /> each sump. The air vents were between the lateral drain pipes in the LCRS, which allowed <br /> Musco to assess the performance of each portion of the LCRS. Musco used low EC <br /> (approximately 280 pS/cm) water for the test. <br /> Musco injected approximately 50,000 gallons through various air vents into the Pond A LCRS, <br /> but no water was observed in either sump. Musco then examined the Pond A LCRS by using <br /> video equipment to explore the header pipe from both the north and south sumps. According to <br /> the Report, areas of ponded water were observed in the header pipe. These areas were <br /> interpreted as locations where settlement had occurred, which prevented water from reaching <br /> the sumps. Lateral piping could not be explored. In the Report, Musco recommended an <br /> additional attempt to video the lateral drain pipes and possibly retest the LCRS in 2012, but did <br /> not provide an explanation of the failure of the LCRS to convey water to the sump. <br /> Musco injected approximately 28,000 gallons of water into the Pond B LCRS. Musco recovered <br /> approximately 11,000 gallons in the Pond B sumps. This amounts to approximately 40 percent <br /> recovery of injected water in Pond B. The header pipe from the north sump in Pond B was also <br /> examined by video. Areas of ponded water were also observed in the header pipe. This <br /> observation indicates that the LCRS header pipe in Pond B has also settled and does not <br /> properly convey wastewater to the sumps,thus allowing hydraulic head to build up over the <br /> secondary clay liner. <br /> EC values of test water recovered in Pond.B sumps averaged 3,800 pS/cm.The Report did not <br /> address the reason for the elevated EC measurement of the recovered water. Staff is <br /> concerned that the increase in EC value comes from wastewater contaminants in the LCRS or <br /> secondary liner that mixed with the test water as it flowed to the sumps. <br /> Violation of WDRs Order R5-2005-0024 <br /> Discharge Specification B.13 states in part: LCRSs shall be designed, constructed, and <br /> maintained to collect twice the anticipated daily volume of leachate generated by each surface <br /> impoundment and to prevent hydraulic head on the underlying liner at any time. The test of <br /> Pond A indicated that the LCRS is not capable of conveying leachate to the sumps and <br /> preventing hydraulic head on the secondary liner. The test of Pond B showed that the LCRS <br /> has some capacity to convey leachate, but allows hydraulic head to occur on the secondary <br /> liner. Therefore, both impoundments are in violation of Discharge Specification B.13. <br /> Lysimeter Results <br /> Musco also performed maintenance and sampling of the unsaturated zone monitoring system <br /> during 2011. This system is made up of approximately 40 suction lysimeters set at depths of five <br /> and ten feet below the secondary clay liners of the Class II Surface Impoundments. Musco has <br /> recently been proactive in taking steps to keep this detection system operational, and <br /> maintenance of the lysimeters is on-going. Maintenance of the lysimeters appears to be making <br /> the monitoring system more effective at detecting liquid in the unsaturated zone. <br />