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ethylhexyl)phthalate was measured at a trace concentration in the sample collected from well MW-24. In addition,TCFM was measured above the PQL in the sample collected from well MW-10. As discussed in Section 2.1.2, acetone, bromoform and bis(2- ethylhexyl)phthalate are suspected field/laboratory contaminants, since similar concentrations were also measured in QA/QC blanks during the current monitoring period. On behalf of Forward 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 limiting interim fill areas that promote ponding of water. Furthermore, in accordance with CCR Title 27, Section 20937, Forward continues to install additional landfill gas extraction wells, as needed. New Historical Intrawell Maximum Values As shown in the table below, eight new historical intrawell maximum values were measured during the third quarter 2008 monitoring event. New Historical Intrawell Maximum Values Wen Analyte New Value Previous Value MW-10 Acetone* 9.3j gg/L 6.6j gg/L TCFM 0.68 gg/L 0.34j gg/L MW-15 TCFM 0.25j µg/L 0.23j gg/L MW-16 I Total Dissolved Solids 1100 mg/L 1070 mg/L MW-17 Arsenic 0.0098 mg/L 0.0066 m /L MW-18 Arsenic 0.0079 mg/L 0.0047 mg/L MW-19 Arsenic 0.0150 mg/L 0.0062 mg/L MW-15 Bicarbonate 610 m L 510 mg/L Notes: j—Trace Value between the(MDL and PQL). *—Confirmed Laboratory Contaminant. Concentration Limit Thresholds Data obtained during the third quarter 2008 monitoring period were compared to concentration limits (CLs)as specified in the RPCMP for the Forward Landfill. CLs were calculated by Herst& Associates and are included in Appendix D. Table 24 summarizes CLs that were exceeded in samples collected from groundwater monitoring wells during the third quarter 2008. As summarized in this table, CLs were exceeded for wells MW-IA, MW-2A, MW-3A, MW-10, MW-13,MW-14, MW-15, MW-16, MW-17,MW-18, MW-19, MW-21, and MW-23R. In accordance with the RPCMP, wells with CL exceedances (other than arsenic,bicarbonate, hexavalent chromium, nitrate as nitrogen, and sulfate, which the RPCMP do not consider impact constituents) n:\zoos 0010\Fn_Qoaa« 6 Geologic Associates