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eo o is Associates Geologists, Hydrogeologists and Engineers July 29, 2008 JN:2008-0010 Mr. Ross Atkinson Central Valley Regional Water Quality Control Board 11020 Sun Center Drive, Suite 200 Rancho Cordova, CA 95670-6114 SECOND QUARTER 2008 WATER QUALITY MONITORING REPORT FORWARD LANDFILL SAN JOAQUIN COUNTY, CALIFORNIA On behalf of Forward Incorporated (Forward), Geologic Associates (GLA) is pleased to submit the subject water quality monitoring report for the Forward Landfill in compliance with reporting requirements of the Regional Water Quality Control Board- Central Valley Region (RWQCB) Waste Discharge Requirements (WDRs) Order Number R5-2003-0049,which combined operations at the former Austin Road and Forward Landfills under a single permit, and referred to as the Forward Landfill. The Forward Landfill is regulated by two monitoring programs including the RWQCB WDR Order No. R5-2003-0049; and the Department of Toxic Substances Control (DTSC) Post Closure Permit No. CAD 990794133. A separate annual report is submitted to the DTSC in March each year addressing the Post Closure Permit Requirements and focuses on Waste Management Unit(WMU)A. However, all analytical data are provided in each report and the requirements of each program are being satisfied. This report presents quarterly sampling results for the reporting period dating from April I to June 30, 2008 (second quarter 2008) and also includes an analyses of the constituents of concern (COCs)that were identified in Order No. R5-2003-0049. For the Forward Unit, environmental monitoring for the second quarter 2008 yielded results similar to previous quarters. Seven new historical intrawell maximum values were measured in samples collected from groundwater monitoring wells. Estimated trace-level volatile organic compounds (VOCs)were measured in wells MW-14 and MW-21. Concentration limits (CLs)were exceeded for one or more monitoring parameters in samples from 12 wells. In accordance with the revised post- closure maintenance plan(RPCMP), seven wells with exceedances of CLs that are potential impact constituents will be resampled in August 2008 (during the third quarter 2008 sampling event),and a second independent sample will be collected in September 2008. The results of the two retests will be submitted to DTSC and RWQCB under separate cover. Historically, similar exceedances of inorganic CLs have been measured and verified in samples collected from detection monitoring program (DMP)monitoring wells at the Forward Unit, followed by no release demonstrations,which have concluded that the inorganic CL exceedances are likely the result of naturally occurring conditions and therefore not indicative of a release from the Forward Landfill. During the second quarter 2008 monitoring period, methane concentrations did not exceed the regulatory limit of five percent in perimeter soil-pore gas probes at the Forward Unit. Forward continues to install additional landfill gas extraction wells (as needed), and makes regular adjustments to the landfill gas extraction system to optimize efficiency of the landfill gas extraction system. 16885 W. Bernardo Dr., Suite 305, San Diego, CA 92127 Phone: (858) 451-1136 Fax: (858) 451-1087