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1.0 Surface Water Monitoring During the first quarter 2010 monitoring event, surface water sampling was performed at the French Camp Landfill by Del-Tech Geotechnical Support Services, Inc. (Del-Tech). Surface water samples were collected form monitoring points SW-1, SW-2, and SW-3. Upstream surface water monitoring points SW-1 in Walker Slough and SW-2 in French Camp Slough are sampled to provide background monitoring data. Surface water monitoring point SW-3 is downstream at the confluence of the sloughs. The Waste Discharge Requirements (WDRs)stipulate quarterly analysis for field parameters(pH, specific conductance, temperature, and turbidity) and monitoring parameters (bicarbonate, calcium, carbonate, chloride, magnesium, nitrate, potassium, sodium, sulfate, total dissolved solids [TDS], and volatile organic compounds [VOCs]). The field results provided by Del-Tech and the laboratory results provided by BC Laboratories, Inc. (BC Labs) for the first quarter 2010 surface water monitoring event are summarized on Table 2.1. The historical surface water data are presented in Appendix A. Time series concentration plots are presented Appendix B. For VOCs, only those compounds that exhibited detections at surface water monitoring points during the first quarter 2010 monitoring event were plotted. The concentration limits were calculated from data collected through the first quarter 2010 monitoring event. The statistical analysis calculations for surface water monitoring points are presented in Appendix B. Information on the development of the concentration limits can be found in the Fourth Quarter/Annual 1999 Monitoring Report, French Camp Landfill prepared by CH2M HILL in January 2000. A copy of the statistical analysis methodology is presented in Appendix C. There were no constituents that exceeded concentration limits at SW-3 during the first quarter 2010 monitoring event. One VOC was detected at a surface water point during the first quarter 2010 monitoring event. Toluene was detected at SW-1 (0.25 ug/L), SW-2 (0.23 ug/L), and SW-3 (0.21 ug/L). All of these concentrations are below the laboratory reporting limit (RL) of 0.50 ug/L. Toluene has previously been detected at both upstream and downstream surface water monitoring points at concentrations up to 0.25 ug/L,but has not been confirmed during a subsequent monitoring event. Historical data from the surface water sampling points were evaluated for temporal trend using Mann-Kendall / Sen's Slope trend analysis. Graphs and summary tables of the Mann-Kendall / Sen's Slope analyses are presented in Appendix B. Only turbidity at SW-1, SW-2, and SW-3 exhibited an increasing trend according to the Sen's Slope analysis. As noted above, SW-1 and SW-2 are background surface water monitoring points, and trends in the surface water quality at these points are not indicative of an impact from the facility. Given that turbidity exhibits a statistically significant increasing trend at background surface water monitoring points SW-1 and SW-2, the increasing trend in turbidity at SW-3 should be considered reflective of regional impacts and/or non-facility impacts. Chloride at SW-2, nitrate at SW-1, sulfate at SW-1, and total dissolved solids at SW-1 exhibited decreasing trends according to the Mann-Kendall/ Sen's Slope analysis. Soil cover has been placed over the waste material to prevent ponding of stormwater and to protect surface water. In addition, a perimeter ditch directs stormwater to a basin in the southeast corner of the site. A smaller ditch collects stormwater from the grinding area in the northeast corner of the site. Inspection and maintenance procedures for these stormwater control structures are provided in the site's Stormwater Pollution Prevention Plan. The facility reported that these