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quarter 2008 monitoring period. Review of the November 2008 leachate sample data indicates no potential new COCs, and therefore, no retesting is required. 4.0 ANNUAL SUMMARY 4.1 GENERAL During the 2008 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 2008 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 1,351,902 tons of solid waste during the 2008 monitoring year. Figure 1-3 shows the approximate location of waste placement during 2008 monitoring year. The following types of waste were received: Non-hazardous solid waste— 1,321,004 tons Asbestos—2,736 tons Sewage and wastewater treatment sludge—28,162 tons 4.2 LANDFILL GAS MONITORING The CEHD regularly inspects the Forward Landfill for methane concentrations in perimeter soil-pore gas probes. During the 2008 monitoring year,methane concentrations in all perimeter soil-pore gas probes have remained below 5 percent, suggesting that the landfill gas extraction system is effectively reducing methane concentrations along the perimeter of the site. Furthermore, in accordance with CCR 27, Section 20937(a) (1),methane monitors are installed in all buildings at the site to protect public health and safety and the environment. During the 2008 monitoring year,no methane was detected in any of the facilities buildings. 4.3 COMPLIANCE RECORD During the 2008 monitoring year, CLs were consistently exceeded in Forward Unit wells MW-lA, MW-2A, MW-3, MW-10, MW-13, MW-14, MW-15, MW16, MW-17, MW-18, MW-19, and MW-21. The inorganic CL exceedances have been measured and verified in retest samples collected from the monitoring wells at the Forward Unit, followed by NRD. In each case the NRD has concluded that the CL exceedances are likely the result of naturally occurring conditions and therefore not indicative of a release D:\200"010\FA_4Q03.doc 14 Geologic Associates