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Water Quality Monitoring Report Forward Landfill ® Surface water monitoring stations ASW-1 (upstream) and ASW-2 (downstream) were sampled on January 17, 2017 for the first quarter 2017 monitoring period. Table 3-8 summarizes the current analytical results of surface water samples collected at the Austin Unit. As shown on Table 3-8, similar concentrations were measured in both up and downstream samples and no VOCs were detected in either sample. Furthermore, no CLs were exceeded at downstream point ASW-2. 3.1.11 Corrective Action Monitoring The Groundwater Treatment Facility (GTF) at the Austin Unit has been operational since 1994 to mitigate impacts from landfill releases. Impacted groundwater is extracted from four wells (EW-1, EW-2, EW-311, and EW-4) that pump groundwater through an air stripper treatment system to remove VOCs. Treated groundwater is discharged to an infiltration pond (constructed in 2003) north of the Austin Road Unit of the Forward Landfill. During the monitoring period, the GTF treated 22.5 million gallons of groundwater and removed approximately 0.46 pounds of VOCs. Details regarding corrective action remediation system operations and performance evaluation for the first quarter 2017 are presented in Appendix C. 3.2 Summary Groundwater quality conditions beneath the Austin Unit during the first quarter 2017 monitoring period indicates that CL exceedances and/or non-statistical indication of release were identified at DMP wells AMW-6 and AMW-12 during the first quarter 2017 monitoring period. The PCE concentration measured at DMP well AMW-12 (6.3 ug/L) exceeded the state and federal MCL (5.0 ug/L) and also exhibited an increasing trend. In a letter dated April 21, 2017, the RWQCB was notified of the CL exceedances in well AMW-12. For the CAP/evaluation wells, 16 of 28 wells reported one or more VOCs exceeding a PQL, with CAP well AMW-22S having the highest total concentration of VOCs (113.98 µg/L). Surface water samples collected from the upstream and downstream surface water monitoring stations during the first quarter 2017 monitoring period were generally consistent with each other; no VOCs were detected and no CLs were exceeded. For vadose zone monitoring stations soil-pore liquid sample was collected from lysimeter FU-05 and a quantifiable concentrations of four VOCs measured in lysimeter FU-05. Under the existing CAP, the GTF pumped 22.5 million gallons of groundwater removing an estimated 0.46 pounds of VOCs. Project No.5017.1030 I Water Quality Monitoring Report 13 April 2017