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well MW-9A is well below risk-based concentrations and has been attributed to landfill gas (LFG). Given the distance well MW-6A is from the landfill (approximately 0.25 miles), the chloroform concentrations recently measured in well MW-6A are not believed to be the result of a release from the landfill, particularly since chloroform has almost never been detected in groundwater monitoring wells at the landfill. Concentration Limits For DMP monitoring wells at the French Camp Landfill,concentration limits (CLs) provided in WDR R5-2007-0046 are used for the water quality protection standards (WQPS). All CLs are provided in Table 2 for comparison with current monitoring data. The following table presents constituents that were found to exceed a CL and also provides results of the non-statistical VOC Special analysis: CONSTITUENTConcentration DMP Monitoring Wells Limit MW-6A* MW-7A"I MW-SA I MW-9A I MW-911 I MW-10A ENERAL CHEMISTRY(mg/1) H 6.9-10.21 6.84 hloride 249 490 hloroform VOC Special 6.8 richlorofluoromethane VOC Special NOTES: (*)—Background Well. A shaded cell indicates that the current value was measured below the CL. Only constituents that exceeded a CL are provided in the table above. All CLs are provided in Table 2. Trend Analysis In order to evaluate changes in water quality in DMP wells at the French Camp Landfill, laboratory-analyzed constituents and pH values that exceeded CLs and VOCs measured above PQLs were evaluated using Sen's Slope trend analyses to determine if statistically significant increasing or decreasing trends were evident. No statistically significant trends were identified for constituents that exceeded CLs. Trend analyses are presented in Appendix D. 4.5 LEACHATE MONITORING The laboratory results for leachate monitoring well MW-2 are summarized in Table 3. As shown on Table 3, no VOCs were detected in leachate monitoring well MW-2 during the monitoring period. 4.6 SURFACE WATER MONITORING Field and laboratory results for surface water monitoring stations (SW-1, SW-2, and SW-3) for the current monitoring period are summarized in Table 4. Stations SW-1 and SW-2 are located upstream of the landfill within the Walker and French Camp Sloughs (respectively)and are used as background sampling points. Station SW-3 is located downstream of the landfill at the confluence of the two sloughs. A comparison of upstream(SW-1 and SW-2) to downstream(SW-3) surface water samples indicates 0:2013-002MC1sA13.dm 4 Geo-Logic Associates