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Water Quality Monitoring Report <br />Forward Landfill <br />as needed. Forward is also in the process of bringing several inactive LFG extraction wells <br />online in the vicinity of well MW -17. <br />Concentration Limit Thresholds <br />In accordance with RWQCB Order No. R5.-2014-0006, the routine inorganic monitoring <br />data obtained from the Forward Unit during the fourth quarter 2015 monitoring period <br />were compared to intrawell concentration limits (CLs) established for each well. Details <br />on the statistical analysis for the established CLs are presented in Appendix G of the <br />fourth quarter 2014 Water Quality Monitoring Report for the Forward Landfill (GLA, <br />2014) and will be updated during the fourth quarter 2016. As summarized in Table 2-4, <br />the following CLs were exceeded during the fourth quarter 2015 monitoring period. <br />• MW -10 — Nitrate as nitrogen <br />• MW -18 — Bicarbonate <br />• MW -24 —Chloride <br />In a letter dated January 25, 2016, the RWQCB was notified of these CL exceeclances and <br />retesting is scheduled for February 2016. The results of the verification sampling will be <br />reported under separate cover. <br />Tracking Mode <br />Constituent concentrations reported above a CL and confirmed in retest samples within <br />the previous three years of monitoring were placed in "Tracking Mode" and are <br />evaluated for temporal trends using Mann -Kendall trend analyses. The results of the <br />trend analyses indicate that increasing trends were calculated for chloroform at well <br />MW -17 (Table 2-5). Of note, chloroform concentrations are well below the established <br />state and federal maximum contaminant levels (MCLs) and the increasing trend is <br />believed to be associated with landfill gas. Mann -Kendall trend analyses calculations are <br />presented in Appendix G. As discussed previously Forward is in the process of <br />increasing LFG extraction in the vicinity of this well. <br />2.1.5 Vaclose Zone Monitoring <br />The current vaclose-zone monitoring network at the Forward Unit consists of 10 <br />lysimeters (seven suction lysimeters and three pan lysimeters). These lysimeter <br />locations are shown on Figure 2-1. As shown on Table 2-6, pan lysimeters were <br />reported dry and there was an insufficient volume of soil -pore liquid (4 mL) for <br />collection of samples from suction lysimeters. <br />M:\ 2015.0014\FA_4Q15.docx 8 <br />1/29/2016, Rev. 0 <br />