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concentrations(between the method detection limit [MDL] and the PQL) in the sample collected from wells W-10; PCE and TCE were measured above the PQL, and 1,1- DCA, cis-l,2-dichloroethene(cis-1,2-DCE), DCDFM, and TCFM were detected at trace concentrations in the sample collected from well MW-14; DCDFM and TCFM were measured at trace concentrations in the sample collected from well MW-15; and carbon disulfide was measured at a trace concentration in the sample collected from well W- 19. On behalf of Forward Inc., GLA prepared a letter report dated February 14, 2001 (RQCB 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 WU-B. The particular VOCs detected in samples during the current monitoring period appear to support this conclusion. 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, 18 new historical intrawell maximum values were measured during the first quarter 2010 monitoring event. It should be noted, however, that toluene and acetone concentrations are suspected field/laboratory contaminant since similar concentrations were measured in QA/QC blank samples during the monitoring event. New Historical Intrawell Maximum Values Well Analyte New Value Previous Value MW-2A Toluene* 0.19j /L ND MW-10 DCDFM 0.97 g/L 0.83 g/L TCFM 0.78 g/L 0.68 /L MW-14 cis-1,2-DCE 0.39' g/L 0.28j g/L DCDFM 0.33j g/L 0.25j g/L TCE 0.85 g/L 0.55 g/L TCFM 0.24' g/L 0.15j L MW-15 DCDFM 0.24j g/L 0.23' g/L MW-17 Acetone* 5.3j g/L ND MW-19 Carbon Disulfide 0.38j g/L ND MW-22 Calcium 100 mg/L 98 mg/L Chloride 42 mg/L 37 mg/L Magnesium 50 mg/L 48 mg/L Oil and Grease 2.5 mg/L ND Sodium 53 mg/L 52 mg/L Strontium 1.1 mg/L 1.0 mg/L Sulfate 110 mg/L 96 mg/L Total Dissolved Solids 770 mg/L 680 mg/L Notes: j—Trace value(between the MDL and PQL). *-Suspected field/laboratory contaminant. D:\2010_0013TA_1 Q10.doc 6 Geologic Associates