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Water Quality Monitoring Report <br /> Forward Landfill <br /> well below state and/or federal maximum contaminant levels (MCLs), and were placed <br /> in "tracking mode" and are being evaluated quarterly for temporal trends. <br /> On behalf of Forward Inc., GLA performed an assessment of the source and potential <br /> impacts of low-level VOCs in groundwater adjacent to the Forward Landfill (GLA, 2001). <br /> It was concluded that the sporadic detection of low-level VOCs in groundwater (and <br /> lysimeter samples) at the Forward Unit are most likely due to landfill gas from unlined <br /> unit WMU-B. Forward has continued to minimize gas related impacts to groundwater <br /> by preventing ponding of water through regular site maintenance. Furthermore, in <br /> accordance with CCR Title 27, Section 20937, Forward continues to install additional <br /> landfill gas extraction wells, as needed. <br /> Concentration Limit Thresholds <br /> In accordance with RWQCB Order No. 115-2014-0006, the routine inorganic monitoring <br /> data obtained from the Forward Unit during the third 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). As summarized in Table 2-4, the following CLs were exceeded during the third <br /> quarter 2015 monitoring period. <br /> • <br /> MW-10—calcium <br /> • MW-18—bicarbonate, calcium, magnesium <br /> • MW-19—bicarbonate, calcium, strontium <br /> In a letter dated October 14, 2015, the RWQCB was notified of these CL exceedances <br /> and retesting is scheduled for October 2015. The results of the verification sampling will <br /> be 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 and bicarbonate at well MW-18 (Table 2-5). Of note, both increasing trends are <br /> for constituents believed to be associated with landfill gas and chloroform is well below <br /> the established state and federal maximum contaminant levels (MCLS). Mann-Kendall <br /> trend analyses calculations are presented in Appendix G. <br /> is <br /> M:\2015.0014\FA 3Q15.docx 7 <br />