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Water Quality Monitoring Report Forward Landfill ® samples) at the Forward Unit are most likely due to landfill gas from unlined unit WMU- B. Forward has continued to minimize gas related impacts to groundwater by preventing ponding of water through regular site maintenance. Furthermore, in accordance with CCR Title 27, Section 20937, Forward continues to install additional landfill gas extraction wells, as needed. Concentration Limit Thresholds In accordance with RWQCB Order No. R5-2014-0006, the routine inorganic monitoring data obtained from the Forward Unit during the first quarter 2015 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 2-4, the following CLs were exceeded during the first quarter 2015 monitoring period. MW-2A—chloride MW-18—bicarbonate, nitrate-N In a letter dated April 1, 2015, the RWQCB was notified of these CL exceedances and retesting is scheduled for April 2015. The results of the verification sampling will be reported under separate cover. 2.1.5 Vadose Zone Monitoring The current vadose-zone monitoring network at the Forward Unit consists of 10 lysimeters (seven suction lysimeters and three pan lysimeters). These lysimeter locations are shown on Figure 2-1. As shown on Table 2-5A, samples were collected from LY-BG-1 and pan lysimeter WMU D-01N, all other lysimeters were reported dry or produced an insufficient volume to sample. As summarized on Table 2-513, eight VOCs were detected (five above a PQL) in the soil-pore liquid sample collected from pan lysimeters WMU D-01N during the monitoring period. For pan lysimeter WMU-D01N, approximately 2350 gallons of liquid were pumped from the pan and discharged to surface impoundment WMU F (North). 2.1.6 Leachate/Surface Impoundment Monitoring Leachate sumps and surface impoundments are inspected weekly by Forward Landfill personnel. If leachate is detected in a sump, it is pumped into the surface impoundment WMU F (North) for evaporation. During the first quarter 2015, leachate was observed at holding areas WMU D-89, WMU D-93/94, WMU D-01 N/S, and WMU D- 02 and a total of 28,600 gallons of leachate was removed from the lined areas at an average rate of 314 gallons per day. For surface impoundment WMU-F (North), freeboard ranged from approximately 2.58 to 9.58 feet during the first quarter 2015 M:\2015.0014\FA 1Q15.docx 7 4/27/2015,Rev.0