Laserfiche WebLink
3 <br />Mr. Todd Del Frate <br />Corral Hollow Fourth Quarter and Annual 2024 Report <br /> <br /> <br />below the PQL. These VOCs have been detected at this monitoring well regularly since the well <br />was installed although most detections were below the PQLs. A “significantly decreasing” trend <br />was reported for cis-1,2-dichloroethene, while “significantly increasing” trends were reported for <br />dichlorofluoromethane and PCE. The PQL for PCE is generally 0.5 μg/L and all reported <br />concentrations for PCE have been trace concentrations below 0.5 μg/L. <br />Deep Aquifer <br /> <br />MW-6 – Concentrations of the general water quality parameters were within the established <br />concentration limits, with the exception of turbidity. “Significantly increasing” trends were <br />reported for EC, turbidity, calcium, magnesium, total alkalinity, bicarbonate alkalinity, chloride, <br />sulfate, and TDS. VOCs were not detected. <br />MW-7 – Concentrations of the general water quality parameters were within the established <br />concentration limits with the exception of sulfate. A “significantly increasing” trend was reported <br />for sulfate. No VOCs were reported. <br />MW-12 – Concentrations of the general water quality parameters were within the established <br />concentration limits with the exception of pH. “Significantly decreasing” trends were reported for <br />turbidity and potassium. <br />One (1) VOC, trichlorofluoromethane, was reported at the PQL. Trichlorofluoromethane has <br />only been detected above the PQL during the Second and Third Quarter 2023 sampling events. <br />The verification sample results from Third Quarter 2023 initiated preparation of an Amended <br />Report of Waste Discharge and Evaluation Monitoring Program Report, which was submitted on <br />November 6, 2023. During the special EMP sampling events conducted in September 2023, <br />Fourth Quarter 2023, and First Quarter 2024, trichlorofluoromethane was detected at trace <br />concentrations at well MW-12. An Engineering Feasibility Study is being prepared to assess <br />alternative LFG treatment methodologies to better address the LFG VOC source at the landfill. <br />“Significantly increasing” trends were reported for trichlorofluoromethane and total VOCs. <br />Although the Sanitas program indicates an increasing trend, the concentration was at the PQL <br />during Fourth Quarter 2024 and concentrations were at trace levels below the PQL for the <br />previous four sampling events. Historical data indicates that the highest concentration of <br />trichlorofluoromethane reported at this monitoring well was during Third Quarter 2023 <br />verification sampling event at a concentration of 0.59 µg/L (slightly above the PQL). Future <br />monitoring results will be assessed to determine data trends. As previously noted, VOCs <br />reported below the PQL may not be accurate or even be present at the value reported.