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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 QA/QC Results The QA/QC program completed for the second quarter 2011 water quality monitoring event at the Austin Unit included analyses of two field blanks, one trip blank, and four laboratory method blanks. The trip and field 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 a trace concentration of chloroform was detected in one of the method blank, hexavalent chromium was detected above the PQL in another method blank, and methylene chloride was detected above the PQL in one field blank during the monitoring period. Review of the analytical data indicates that a similar concentration of hexavalent chromium was detected in the primary sample collected from well AMW-5R and similar concentrations of chloroform were detected in the primary samples collected from domestic wells 7898-A and 8106-A. These results were flagged as a suspected laboratory contaminants. During the second quarter 2011 monitoring event, a duplicate sample was collected from well AMW-I and labeled DUP. As shown on Table 3-2, for quantifiable concentrations greater than the PQL,the duplicate sample analyses yielded good correlation (within 4%) with the primary sample. Review of laboratory analysis dates with the required holding times indicates all of the samples were submitted and analyzed within the required holding times during the second quarter 2011. Based on the QA/QC results, it is concluded that the laboratory data generated for the second quarter 2011 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 and historical 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-northeast with an average hydraulic gradient of 0.002 ft/ft. D:\2011_00501FA 2QII.doex 8 Geologic Associates