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3.0 AUSTIN UNIT 3.1 WATER QUALITY MONITORING 3.1.1 Sampling and Laboratory Analyses During the first quarter 2008, depth-to-water measurements were recorded in the groundwater monitoring wells on February 4, 2008 and the Austin Unit's DMP and CAP groundwater monitoring wells were sampled by ATC between February 4 and 19, 2008. Both surface water stations were sampled on February 4, 2008. A single sample set was collected from each sample point with sufficient liquid and submitted to BC for analysis of the parameters stipulated in RWQCB Order No. R5- 2003-0049. Table 2-1 presents the monitoring schedule and summarizes the analytical methods utilized during the current monitoring period. 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, surface water monitoring points, and leachate were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets, raw laboratory data, certificates of analyses, and chain-of-custody records related to the sampling program are included in Appendix C. The results of both field and laboratory analyses are summarized in Tables 3-1 through 3-6. 3.1.2 QA/QC Results The QA/QC program completed for the first quarter 2008 water quality monitoring event at the Austin Unit included analyses of four field blanks, five trip blanks, five laboratory method blanks, and one duplicate sample. The trip, field, and laboratory method blanks were analyzed for VOCs by EPA Method 8260 and are included with the laboratory data in Appendix C. The results of the QA/QC program indicate that trace levels of ethanol were detected in a field blank and trip blank, and chloroform was measured above the PQL in a field blank during the first quarter 2008 monitoring event. Review of the primary sample results indicates that similar concentrations of ethanol were detected in several of the primary sample collected, and as a result,were flagged as suspected field/laboratory contaminants. A duplicate sample was collected from well W-6 and labeled AMW-DUP. Duplicate groundwater results are presented along with the primary data in Table 3-1. Comparison of the values in the primary sample with the duplicate indicates that there was good agreement(within 5%). Review of laboratory analysis dates with required holding times indicates that all samples were submitted and analyzed within the required holding times during the first quarter 2008. Based on the results of the laboratory blank and duplicate analyses, it is concluded that the laboratory data generated for the first quarter 2008 monitoring period are generally acceptable. D:\2007-0WTA-1Q08.doc 8 Geologic Associates