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Water Quality Monitoring Report Forward Landfill is Inc., GLA prepared a letter report dated February 14, 2001 (RWQCB Case No. 2209), to assess the source and potential impacts of low-level VOCs in groundwater adjacent to the Forward Landfill. The letter report concluded that the sporadic detection of low- level VOCs in groundwater (and lysimeter 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. 115-2014-0006, the routine inorganic monitoring data obtained from the Forward Unit during the second quarter 2014 monitoring period were compared to intrawell concentration limits (CLs) established for each well. Since the new WDR requires annual updates to the CLs and CL have not been updated since 2011, inorganic CLs for the Forward Unit wells were recalculated and are presented in Table 2-4. Details on the CL update are presented in Appendix D of the Second 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 second quarter 2014 monitoring period. • pH at wells MW -3 and MW -23R • Nitrate at well MW -14 • TDS at well MW -17 Trend analyses were performed for wells and constituents that exceeded respective CLs. However, no statistically significant increasing temporal trends were identified for any of the inorganic constituents that exceeded a CL. Trend analyses are included in Appendix D. The inorganic CL exceedance for wells MW -3 and MW -14 are believed to be related to the groundwater gradient reversal in the northeast corner of the landfill. The CL exceedance for well MW -23R is attributed to background conditions. Accordingly, these CL exceedances are not believed to be related to a release from the landfill and in the absence of VOCs at these wells, no further action is recommended at this time. 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). The lysimeter locations are shown on Figure 2-1. As shown on Table 2-5A, samples were collected from LY -BG - 1, LY -E2, LY -W2, and LY -E1, and all other lysimeters were reported dry. Only VOC analysis could be performed due to insufficient soil -pore liquid available for sampling. As summarized on Table 2-513, no VOCs were detected in the soil -pore liquid samples collected during the 2014 monitoring period. Of note, there was no access port to M:\ 2014.0012\FA_2Q14.docx 7 7/29/2014, Rev. 0