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However, given the fact that increasing trends for turbidity were calculated for uply'adient surface water stations SW-1 and SW-2, the increasing trend in turbidity at surface water station SW-3 is considered reflective of regional conditions and/or are non-facility related. 6.4 SOIL-PORE GAS During the first quarter 2007 sampling was performed using Tedlar bags, which resulted in low level concentrations of methane in all of the samples collected. After discussing the first quarter 2007 soil-pore gas results with the laboratory, soil-pore gas samples were subsequently collected using summa canisters beginning in the second quarter 2007. With the exception of the first quarter 2007, soil-pore gas conditions at the French Camp Landfill have remained relatively consistent. No methane was detected in soil-pore gas monitoring probes during the second, third, and fourth quarters of 2007, while VOC constituents and concentrations have varied from quarter to quarter. 6.5 COMPLIANCE RECORD On May 4 2007 WDR Order No. - y RS-2007 0043 was formally adopted replacing Order No. R5-2004-0159. Historically, low-level VOCs have been sporadically detected in downgradient groundwater monitoring wells at the French Camp Landfill. In a letter dated January 16, 2007, the RWQCB was notified of the non-statistical indication of a release at well MW-9A, which was suspected to be related to the recent placement of a final cover system on the landfill and landfill gas (LFG) generation. In a meeting with the RWQCB on March 9, 2007, the RWQCB agreed to quarterly monitoring of existing groundwater monitoring wells and soil-pore gas probes through May 2008 to evaluate the significance of LFG at the site. During the 2007 monitoring year the French Camp Landfill did not accept waste and the landfill has been formally closed. No NOVs were issued by the LEA or CIWMB during the 2007 monitoring year and the site is currently in compliance. 7.0 SUMMARY Groundwater quality conditions beneath the French Camp Landfill during the fourth quarter 2007 monitoring period are generally similar to those observed in previous monitoring periods. During the fourth quarter 2007 monitoring period, inorganic CLs were exceeded in DMP wells MW-8A, MW-9A, MW-913, and MW-10A. In addition, organic constituent results indicate trace concentrations of TCFM and 1,2-DCA were measured in the samples collected from well MW-9A and MW-913, respectively, which are likely related to landfill gas generation following placement of the final cover system on the landfill. D:0003_021%FC_4Q07.doc 7 Geologic Associates