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an infiltration pond. During the monitoring period, the GTF treated 7,240,022 gallons of groundwater at an average flow rate of 68 gallons per minute, or 98,619 gallons per day. During the monitoring period,the GTF removed approximately 0.987 pounds of VOCs. On October 26, 2010, it is calculated that the GTF was taken offline for repairs to the air stripper tower(replacement of packing media) and replacement of a calcified discharge pipe from the air stripper to the infiltration basin. Repairs to the GTF were completed, and with the exception of extraction well EW-3R, the system was brought back online on December 10, 2010. Extraction well EW-3R is currently offline due to pump failure. 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the fourth quarter 2010 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-13 and AMW-14, however, with the exception of the barium concentration measured in well AMW-14, no CLs were exceeded for constituents that exhibited statistically significant increasing trends. It should be noted,however, that the barium concentration measured in the sample collected from well AMW-14 is within the historical range of values observed at this well, and is well below the state primary drinking water standard. In the CAP wells, trend analyses are performed instead of comparison to CLs. During the current monitoring period, statistically significant increasing trends were noted for one or more VOC constituents in CAP wells AMW-1, AMW-10, AMW-19, and AMW-1 9BR, while one or more decreasing VOC trends were noted in CAP wells AMW-1, AMW-4, AMW-10, and AMW-I 1. The increasing cis-1,2- DCE trends in wells AMW-I and AMW-10, suggest that active reductive dechlorination is occurring in the vicinity of these wells. During the fourth quarter 2010 monitoring period the leachate results are generally similar to those observed historically. During the fourth quarter 2010 monitoring period, 12 dissolved metal constituents were detected with seven measured above the PQL; three VOCs were detected above the PQL; and two trace level SVOCs were detected. No pesticides or herbicides were detected in the leachate sample collected during the fourth quarter 2010 monitoring period. Review of the November 2010 leachate sample data indicates no new COCl were detected. 4.0 ANNUAL SUMMARY 4.1 GENERAL During the 2010 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 tabular summary of the 2010 annual monitoring data is provided in Appendix D. Time-series plots and piper diagrams depicting groundwater and surface water constituent concentrations,prepared by Herst, are presented in Appendix D. In addition, well hydrographs illustrating historical groundwater elevations, well screen elevations, and pump intake elevations are also included in Appendix D. D:\2010_0013\FA_4QI0.doc 14 Geologic Associates