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monitoring station were sampled by Del-Tech Environmental Support Services(Del- Tech) on November 27, and December 4, 2012. The lysimeters were checked for soil- pore liquid on November 28, 2012, and Del-Tech reported that all lysimeters were dry. Of note,there was no access port to inspect pan lysimeters WMW-DOIN, WMW-DOIS, and WMW-D02. Samples were collected by Del-Tech from each sample point containing sufficient liquid and submitted to BC Laboratories (BC) of Bakersfield, California, a state certified laboratory under contract to Forward. During the fourth quarter 2012 monitoring period, samples were analyzed for the routine monitoring parameters 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 oxidation-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, lysieter, 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 fourth quarter 2012 water quality monitoring event included analyses of two trip blanks, four laboratory method blanks, and one duplicate sample. The trip blanks were 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 no VOCs were detected in trip or method blanks during the monitoring period. Inorganic constituents including chloride, hexavalent chromium, arsenic, magnesium, iron,manganese, and tin were measured at trace concentrations in method blanks analyzed with groundwater and leachate samples. These constituents were measured at very low concentrations that generally did not affect the interpretation of primary sample results. However, since hexavalent chromium is only detected intermittently in groundwater samples, it was flagged as a laboratory contaminant on Table 2-2 when the primary sample results were measured at an estimated, trace concentration. A duplicate sample was collected from well MW-22 and labeled FMW- Duplicate. With the exception of arsenic and nitrate (as N), which had relative percent differences (RPD) of 23 percent and 14 percent(respectively), the duplicate sample analyses yielded good correlation with a RPD of seven percent or less. The larger RPD between the primary and duplicate sample may be associated with the detection of arsenic in the method blank that was analyzed with these samples. 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 fourth quarter 2012 monitoring period are generally acceptable and the water quality C:\2012-0025\FA4Q12.doc 4 Geo-Logic /Associates