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3.0 AUSTIN UNIT 3.1 WATER QUALITY MONITORING 3.1.1 Sampling and Laboratory Analyses During the third quarter 2009, depth-to-water measurements were recorded in the groundwater monitoring wells on August 10, 2009 and the Austin Unit's DMP and CAP groundwater monitoring wells were sampled by ATC between August 10 and 12, 2009. Only surface water station ASW-1 had sufficient water for sampling and was sampled on August 10, 2009. 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 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. Field and laboratory analyses are summarized in Tables 3-1 through 3-6. 3.1.2 A/ C Results The QA/QC program completed for the third quarter 2009 water quality monitoring event at the Austin Unit included analyses of three field blanks,three trip blanks, three laboratory method blanks, and one duplicate sample. The trip, field, and laboratory method blanks were analyzed for VOCs by EPA Method 8260 and method blanks were analyzed for all required analyses. The results of the QA/QC program indicate that no VOCs were detected in the QA/QC blanks during the monitoring period. During the third quarter 2009 monitoring event, a duplicate sample was collected from CAP well AMW-1 and labeled AMW-DUP. Duplicate groundwater results are presented along with the primary data in Table 3-2. With the exception of arsenic and nitrate as nitrogen, comparison of the values in the primary sample with the duplicate results indicates that there was good agreement(within 10%). Of note, concentrations less than the PQL were not included in the comparison since these are estimated values. Review of laboratory analysis dates with required holding times indicates that all samples were submitted and analyzed within the required holding times during the third quarter 2009. Based on the results of the laboratory blank and duplicate analyses, it is concluded that generally acceptable QA/QC procedures were exercised and the water quality samples collected from the Austin Unit appear to be representative of water quality at the site. D:\2009-0017\FA-3QO9.doc 8 Geologic Associates