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are sampled for the monitoring parameters summarized in Table 1. Time-series plots depicting groundwater and surface water constituent concentrations and a tabular summary of the historical monitoring are presented in Appendix D and an electronic format is included in Appendix C. Piper diagrams of the quarterly data obtained in 2006 are included Appendix D, and hydrographs of the detection monitoring wells, illustrating historic groundwater elevations,well screen elevations, and pump intake elevations are also included in Appendix D. Discussions of the historical trends in constituent concentrations are presented in Section 5. 6.2 GROUNDWATER Groundwater elevations have remained relatively static over the past year, reflecting seasonal precipitation patterns. Groundwater generally flows east across the site at a gradient ranging from 0.003 to 0.005 ft/ft. Groundwater quality conditions beneath the French Camp Landfill during the 2006 monitoring year are generally similar to those observed in the previous monitoring year. Generally, calculated CLs for the general chemistry parameters were consistently exceeded in wells MW-9A, MW-9B, andMW-l0A and sporadically in wells MW-6A and MW-8A. Furthermore, statistically significant increasing trends were consistently noted for sulfate in well MW-9B and chloride in well MW-10A, while decreasing trends were consistently noted for sulfate in well -7A, and nitrate as nitrogen in wells ® MW-8A and MW-10A. Excluding confirmed laboratory contaminants, low-level concentrations of 1,2-DCA were measured in well -9B during the first, second, and fourth quarter 2006 monitoring periods, and concentrations of TCFM were detected above the PQL in well MW-9A during the third and fourth quarter 2006 monitoring periods. In leachate monitoring well MW-IA, VOCs have been consistently measured above the PQL and up to 11 VOCs have been detected during the first quarter 2006 monitoring period. However, no statistically significant increasing trends for VOCs have been noted in EMP well MW-1 A during the 2006 monitoring year. For leachate monitoring well MW-2, only one trace level VOC(chloroform) was detected in samples from this well during the second quarter 2006 monitoring period. 6.3 SURFACE WATER Water quality conditions for surface water at the French Camp Landfill during the 2006 monitoring year are generally similar to those observed in the previous monitoring years. During the first quarter 2006 monitoring period CLs were exceeded for barium at surface water stations SW-1 and SW-2; during the third quarter 2006 pH values were exceeded at surface water stations SW-1, SW-2, and SW-3; and CLs were exceeded for nitrate as nitrogen in samples from stations SW-1 and -2, and for magnesium in the sample from station SW-3 during the fourth quarter 2006 monitoring period. During the 2006 monitoring year, only turbidity concentrations in all three surface water stations have ® exhibited an increasing trend. However, given the fact that increasing trends for turbidity D:0003_021\FC_f06.doc 6 Geologic Associates