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2008, and sufficient soil-pore liquid was present to collect samples from lysimeters E-2, W-2, LY-A, and LY-BGI. Of note, lysimeter D-01 has been buried and lysimeters E-1, LY-E 1 A, LY-E I B, LY-E2A, LY-E213, FU-03, and WMU D-02 appear to be damaged since they no longer hold a vacuum. A single sample set was collected from each point containing sufficient liquid and submitted to BC Laboratories, Inc. (BC) of Bakersfield, California, a state certified laboratory under contract to Forward. During the fourth quarter 2008 monitoring period, samples were analyzed for the routine monitoring parameters stipulated in RWQCB Order No. R5-2003-0049. In addition, upgradient well MW-24 was sampled for the full list of constituents of concern (COCs). Table 2-1 summarizes site monitoring parameters, analytical methods, and monitoring frequency. Water quality samples were also analyzed in the field for dissolved oxygen, turbidity, temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells and leachate monitoring points were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets, laboratory data, certificates of analyses, and chain-of-custody records for the sampling program are included in Appendix C. The laboratory analyses and field results for groundwater monitoring wells, surface water stations, lysimeter and leachate sampling stations are summarized in Tables 2-2 through 2-7. 2.1.2 QA/QC Results The quality assurance/quality control (QA/QC)program completed for the fourth quarter 2008 water quality monitoring event included analyses of four trip blanks, five laboratory method blanks, one, field blank, and one duplicate sample. The trip, field, and laboratory method blanks were analyzed for volatile organic compounds (VOCs)by EPA Method 8260 and method blanks were analyzed for all of the analytes included in the monitoring program. The results of the QA/QC program indicate that bis(2-ethylhexyl)phthalate, chloroform, and arsenic were detected in one or more of the QA/QC blanks during the monitoring period. Review of the primary sample results indicates that a similar concentration of bis(2-ethylhexyl)phthalate was detected in the primary sample collected from well MW-24 during the monitoring period and was flagged as a suspected laboratory contaminant. Although arsenic was measured in a QA/QC method blank,the concentrations measured in the primary samples were similar to historical results. Therefore, arsenic was not flagged. During the fourth quarter 2008 monitoring event, a duplicate sample was collected from well M -17 and labeled DUP. As shown on Table 2-2, the duplicate sample analyses yielded good correlation(within 10%) with the primary sample results. Review of fourth quarter 2008 sampling dates and laboratory analytical certificates indicates that the laboratory analyses were completed within required holding times. Based on the results of the laboratory QA/QC analyses, it is concluded that the laboratory data generated for the fourth quarter 2008 monitoring period are generally acceptable and the water quality samples collected from the Forward Unit appear to be representative of water quality at the site. DA2008_0010\FA_4Q08.doc 4 Geologic Associates