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laboratory under contract to Forward. During the first quarter 2013 monitoring period, samples were analyzed for the routine monitoring parameters and also included analyses of the five-year COCs stipulated in RWQCB Order No. R5-2003-0049. Table 2-1 summarizes site monitoring parameters, analytical methods, and monitoring frequency. Water quality samples were also analyzed in the field for oxygen reduction potential (ORP),turbidity,temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells and leachate monitoring points were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets, laboratory data, certificates of analyses, and chain-of-custody records for the sampling program are included in Appendix C. The laboratory analyses and field results for groundwater monitoring wells, surface water stations, lysimeter and leachate sampling stations are summarized in Tables 2-2 through 2-7. QA/QC Results The quality assurance/quality control (QA/QC)program completed for the first quarter 2013 water quality monitoring event included analyses of one field blank,three laboratory method blanks, and one duplicate sample. The field blank was analyzed for volatile organic compounds (VOCs) by EPA Method 8260 and method blanks were analyzed for all of the analytes included in the monitoring program. The results of the QA/QC program indicate that two VOCs (toluene and t-butyl alcohol)were detected above the practical quantitation limit(PQL) in field blanks during the monitoring period. Inorganic constituents including chloride, sodium, total organic carbon(TOC), selenium, thallium, and tin were measured at trace concentrations in method blanks analyzed with groundwater and surface water samples. These constituents were measured at very low concentrations that generally did not affect the interpretation of primary sample results. However, similar concentrations of selenium were measured in samples collected from wells MW-13 and MW-23R and were flagged as a suspected laboratory contaminant on Table 2-2. A duplicate sample was collected from well MW-14 and with the exception of hexavalent chromium and selenium, which had relative percent differences (RPD) of 39 percent and 13 percent, respectively,the duplicate sample analyses yielded good correlation with a RPD of less than nine percent. Review of the sampling dates and laboratory analytical certificates indicates that all of the laboratory analyses were completed within required holding times. Based on the results of the laboratory QA/QC analyses, it is concluded that the laboratory data generated for the first quarter 2013 monitoring period are generally acceptable and the water quality samples collected from the Forward 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 to an accuracy of 0.01 foot, and the static water level was recorded on a Well Data Sheet(Appendix C). 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 Forward Unit is summarized in Table 2-3. C:\2013-0021\FA_1Q13.doc 4 Geo-Logic Associates