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Water Quality Monitoring Report Forward Landfill Non-Statistical Data Analysis During the first quarter 2017 monitoring period, the CNSDAM was performed for VOCs detected in the DMP wells. As shown in Table 3-1, non-statistical indications of a release were identified at well AMW-6 as a result of a quantifiable concentration of tetrachloroethene (PCE) and trace-level concentrations of DCDFM and trichloroethene (TCE); and at well AMW-12 for a quantifiable concentration of PCE. Of note, the PCE concentration measured at well AMW-12 (6.3 ug/L) also exceeded the state and federal maximum contaminant levels (MCLS; 5.0 ug/L). In a letter dated April 17, 2017, the RWQCB was notified of the CL exceedances in well AMW- 12. Quantifiable VOCs were placed in "Tracking ode" and are being evaluated quarterly for temporal trends (see below). Concentration Limit Thresholds In accordance with RWQCB Order No. 115-2014-0006, the routine inorganic monitoring data obtained from the Austin Unit DMP wells during the first quarter 2017 monitoring period were compared to intrawell concentration limits (CLs) established for each well. Details on the statistical analysis for the established CLs are presented in Appendix G of the fourth quarter 2014 Water Quality Monitoring Report for the Forward Landfill (GLA, 2014). As summarized in Table 3-3, the following inorganic CLs were exceeded during the first quarter 2017 monitoring period. AMW-6—bicarbonate, calcium, magnesium, potassium, sodium, strontium Tracking Mode Constituent concentrations reported above a CL within the previous three years of monitoring were placed in "Tracking Mode" and are evaluated for temporal trends using Mann-Kendall trend analyses. The results of the trend analyses indicate that an increasing trend was calculated for PCE at well AMW-12 (Table 2-5). Mann-Kendall trend analyses calculations are presented in Appendix F. 3.1.5 Corrective Action/Evaluation Program Field and laboratory results for CAP and EMP wells for the first quarter 2017 monitoring period are summarized in Table 3-2. Excluding suspected laboratory contaminants, 16 of 28 CAP/EMP wells reported one or more VOCs exceeding a Practical Quantitation Limit (PQL), with CAP well AMW-22S having the highest total concentration of VOCs (113.98 µg/L). An annual report discussing the CAP and EMP monitoring results for the Austin Unit was prepared by Geo-Logic Associates (GLA, 2016). 3.1.6 Cannery Waste Land Application Monitoring Field and laboratory results for CWLAM wells for the first quarter 2017 monitoring period are ® summarized in Table 3-4 and were compared to Water Quality Protection Standards (WQPS) Project No.5017.1030 I Water Quality Monitoring Report 11 April 2017