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2.0 FORWARD 2.1 WATER QUALITYNIT 2.1.1 Sampling and Laboratory Analyses During the fourth quarter 2010, depth-to-water measurements were recorded in the groundwater monitoring wells and all of the groundwater monitoring wells were sampled by Del-Tech Environmental Support Services (Del-Tech)between December 15 and 21, 2010. Surface water stations FSW-1 and FSW-2 were sample on December 27, 2010. The lysimeters were checked for soil-pore liquid on December 27, 2010, and Del-Tech reported that all lysimeters were dry. However, lysimeters LY-EIB, LY-E2B, D-93B, WMU-D0l, WMW-D02, WMU-D02 (pan), and FU-03 could not be located or have been buried, while lysimeters LY-EIA and LY-E2A were reported to be plugged. Samples were collected by Del-Tech Geotechnical Support Services (Del-Tech) from each sample point containing sufficient liquid and submitted to Test America Laboratories (Test America) of Buffalo,New York, a California certified laboratory under contract to Forward. During the fourth quarter 2010 monitoring period, samples were analyzed for the routine monitoring parameters stipulated in RWQCB Order No. R5-2003-0049. Table 2-1 summarizes site monitoring parameters, analytical methods, and monitoring frequency. Of note, due to a laboratory error,hexavalent chromium was not analyzed in the samples collected from wells MW-13, MW-16, MW-21, MW-22, MW-23R,MW-24, and DW-9690. Water quality samples were also analyzed in the field for oxygen reduction potential (ORP), 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 A/ C Results The quality assurance/quality control (QA/QC)program completed for the fourth quarter 2010 water quality monitoring event included analyses of two field blanks, two trip blanks, four laboratory method blanks, and one duplicate sample. The field and equipment 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 acetone was measured at trace concentrations in the field blank collected on December 15, 2010. Review of the primary samples indicates that acetone was detected at higher concentrations in the primary samples collected from wells MW-2A and MW-17. Given the fact that acetone is a common laboratory contaminant and has rarely been detected in groundwater monitoring wells at the Forward Unit, these concentrations were flagged as DA2010_0013XFA_4Q10.doe 4 GeoLogic Associates