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access issues offsite EMP wells AMW-22S, A -22,AMW-24SR,AMW-24R, AMW-25, AMW-26R, and AMW-28 were not sampled during the monitoring event. Samples were collected from each sample point with sufficient liquid and submitted to BC for analysis of the routine monitoring 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 ORP,turbidity,temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells, surface water monitoring locations, 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. QA/QC Results The QA/QC program completed for the fourth quarter 2013 water quality monitoring event at the Austin Unit included analyses of one trip blank, laboratory method blanks, and one duplicate sample. The field and trip 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 trip blank sample. In addition, inorganic constituents including chloride,hexavalent chromium,potassium, magnesium, sodium, and sulfate were measured at trace concentrations in method blanks. These constituents were generally measured at very low concentrations that did not affect the interpretation of primary sample results. However, due to similar concentrations, hexavalent chromium results were flagged(with an asterisk)as suspected laboratory contaminants in numerous samples. A duplicate sample was collected from monitoring well AMW-14. Duplicate groundwater results are presented along with the primary data in Table 3-2. The duplicate sample analyses yielded good correlation with quantifiable constituents having a relative percent difference (RPD) of five percent or less. Review of laboratory analysis dates and required holding times indicates that all samples were submitted and analyzed within the required holding times during the fourth quarter 2013. 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. 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. In addition,each accessible EMP well was also sounded for depth to water. 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. C:12013.0021WA_4Q13.d" 8 Geo-Logic Associates