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3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the fourth quarter 2009 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-6, AMW-7, AMW-12, AMW-13, and AMW-14, and with the exception of the barium concentration measured in well AMW-14, none of the CL exceedances exhibited statistically significant increasing trends. Of note, the barium concentration measured in well AMW-14 (0.25 mg/L)is similar to the historical results measured in this well and is well below the California primary drinking water standard (1 mg/L). In the CAP wells, trend analyses are performed instead of comparison to CLs. During the current monitoring period, one or more statistically significant increasing trends were noted for VOC constituents in CAP wells AMW-1, AMW-10, AMW-19, and AMW-I 9BR, while one or more decreasing VOC trends were noted in CAP wells AMW- 1,AMW-4, AMW-I0, and AMW-Il. The increasing cis-1,2-DCE trends in wells AMW-I AMW-10, and AMW-I 9BR suggest that natural degradation of VOCs is occurring in the vicinity of these wells through reductive dechlorinization. During the fourth quarter 2009 monitoring period the leachate results are generally similar to those observed historically. During the fourth quarter 2009 monitoring period, seven dissolved metal constituents were detected with five measured above the PQL, and seven VOCs were detected with three measured above the PQL. No SVOCs,pesticides, or herbicides were detected in the leachate sample collected during the fourth quarter 2009 monitoring period. Review of the November 2009 leachate sample data indicates no new COCs were detected, and therefore, no retesting is required. 4.0 ANNUAL SUMMARY 4.1 GENERAL During the 2009 monitoring year, groundwater elevations and groundwater and surface water sampling was performed at the Forward Landfill on a quarterly basis. The groundwater and surface water samples are analyzed for the monitoring parameters summarized in Table 2-1, and a summary of the 2009 annual monitoring data is provided in Appendix C. Time-series plots and piper diagrams depicting groundwater and surface water constituent concentrations, prepared by Herst, are presented in Appendix D, and an electronic copy of the historical data is included in Appendix C. In addition, well hydrographs illustrating historical groundwater elevations, well screen elevations, and pump intake elevations are also included in Appendix D. According to the Forward Landfill Operations Manager, Forward Landfill received a total of 1,161,707 tons of solid waste during the 2009 monitoring year. Figure 1-3 shows the approximate location of waste placement during 2009 monitoring year. The following types of waste were received: D:0009_0017\FA_4Q09.doc 13 Geologic Associates