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GeoLogic Associates <br /> Geologists, Hydrogeologists and Engineers <br /> July 29, 2008 <br /> JN: 2008-0012 <br /> Mr. Ross Atkinson <br /> Central Valley Regional Water Quality Control Board <br /> 11020 Sun Center Drive, 4200 <br /> Rancho Cordova, CA 95670-6114 <br /> SUBJECT: JANUARY—JUNE 2008 FIRST SEMIANNUAL <br /> WATER QUALITY MONITORING REPORT <br /> FRENCH CAMP LANDFILL <br /> SAN JOAQUIN COUNTY,CALIFORNIA <br /> On behalf of Forward, Inc. (Forward), GeoLogic Associates is pleased to submit the January <br /> through June 2008 semiannual monitoring report for the French Camp Landfill, in compliance <br /> with the California Regional Water Quality Control Board - Central Valley Region(RWQCB) <br /> Waste Discharge Requirement(WDR) Order Number R5-2007-0046. <br /> This report summarizes standard observations and presents the results of surface-water, <br /> groundwater, and soil-pore gas monitoring from January 1 through June 30, 2008 (monitoring <br /> period). A summary of analytical results and time-series concentration plots for field and <br /> monitoring parameters are also included in this report. A description of field procedures and <br /> sampling protocols followed by personnel conducting field monitoring activities is included in <br /> Appendix B of the report. <br /> Groundwater quality conditions beneath the French Camp Landfill during the monitoring period <br /> are generally similar to those observed in previous monitoring periods. Inorganic CLs were <br /> exceeded for calcium, chloride, and potassium in DMP well MW-9B. However, none of these <br /> constituents exhibited a statistically significant increasing trend during the monitoring period. <br /> Organic constituent results indicate no VOCs were detected in groundwater monitoring wells or <br /> the leachate well during the monitoring period. As indicated previously in our letter dated March <br /> 12, 2007, it is not uncommon to find slight increases (microgram per liter)in the concentrations <br /> of VOCs shortly after final cover construction is complete that over time stabilize or decline as <br /> the final cover matures and a geochemical equilibrium is reached. <br /> The results of water quality analyses completed for surface-water monitoring stations are <br /> generally consistent with previous results. Carbon disulfide was detected at a concentration of <br /> 4.1 µg/L in the sample collected from station SW-3. Pursuant to 27CCR,the RWQCB was <br /> notified in writing of the non-statistical indication of a release from station SW-3. No VOCs <br /> were detected in either of the retest samples collected on July 17, 2008, indicating that the <br /> detection of carbon disulfide in the primary sample was a false positive result. Trend analyses <br /> indicate that turbidity at surface water stations S -1, SW-2, and SW-3 depict statistically <br /> ® significant increasing trends. Since turbidity exhibits a statistically significant increasing trend at <br /> 16885 W. Bernardo Dr., Suite 305, San Diego, CA 92127 Phone: (858) 451-1136 Fax: (858) 451-1087 <br />