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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 fourth quarter 2008 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 chloroform was detected above the PQL in two field blanks during the monitoring period. Review of the primary sample results indicates that a similar concentration was detected in the primary sample collected from well AMW-1 during the monitoring period and was flagged as a suspected field/laboratory contaminant. During the fourth quarter 2008 monitoring event, a duplicate sample was collected from well AMW-10 and labeled DUP. Duplicate groundwater results are presented along with the primary data in Table 3-2. With the exception of arsenic, 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 fourth quarter 2008. Based on the results of the laboratory blank and duplicate 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 Austin Unit appear to be representative of water quality at the site. 3.1.3 Groundwater Elevations and Contours Prior to purging and sampling, each well was sounded for water depth using a weighted electronic sounder, and the static water level was recorded on a well data sheet (Appendix Q. The groundwater elevations were calculated for each well by subtracting the depth-to-water measurement from the top-of-casing reference elevation. The current groundwater elevation data for the Austin Unit are summarized in Table 3-4. The groundwater elevation data obtained during this quarterly monitoring period were used to generate the groundwater elevation contour map shown on Figure 3-1,which indicates that groundwater beneath the Austin Unit generally flows to the north at an average hydraulic gradient of approximately 0.002 ft/ft. D:UO08_0010\FA_4QO8.doc 9 Geologic Associates