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Water Quality Monitoring Report Forward Landfill Leachate samples were collected on a quarterly basis and analyzed in the field for pH, specific conductance, temperature, and turbidity. In addition to quarterly monitoring, leachate is sampled annually during the fourth quarter monitoring period for the parameters listed in Table 2-1. The results of quarterly field monitoring measurements and analytical results for the fourth quarter 2014 are presented in Table 3-7. As shown on Table 3-7, six VOCs were detected in the Austin Unit leachate sample. 3.1.10 Surface Water Monitoring Site run-on and run-off control facilities are designed to effectively channel surface water to site stormwater/sedimentation ponds. According to the Operations Manager, there were no discharges to surface water (waters of the United States) during the reporting period. Surface water monitoring stations ASW -1 (upstream) and ASW -2 (downstream) were sampled on December 17, 2014 for the fourth quarter 2014 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, no VOCs were detected in either sample, and with the exception of potassium, no CLs were exceeded. However, the potassium concentration is greater in the upstream sample suggesting that the elevated potassium is a background condition. Of note, CL update was not performed since station ASW -2 was only sampled once since the CLs were last updated. 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, Herst and Associates (2014) calculated that the GTF treated 23.9 million gallons of groundwater and removed approximately 1.19 pounds of VOCs. Details regarding corrective action remediation system operations and performance evaluation for the fourth quarter 2014 are presented in Appendix C. 3.2 Summary Groundwater quality conditions beneath the Austin Unit during the fourth quarter 2014 monitoring period were generally similar to historical results. During the current monitoring period, although it is recognized that well AMW-6 should have been identified as a CAP well, a non -statistical indication of release was identified at well AMW-6 as a result of the detection of three VOCs (two quantifiable concentrations and one estimated -trace concentration). No other VOCs were detected in DMP wells. For inorganic monitoring parameters no CLs were exceeded. For the CAP/Evaluation wells, 17 wells reported one or more VOCs exceeding a PQL, with CAP well AMW-1 having the greatest number of VOCs (11), including nine measured above a PQL. Surface water M:\ 2014.0012\FA_4Q14.docx 13 1/28/2015, Rev. 0