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next monitoring event be utilized to confirm this increase at both the upstream and downstream monitoring locations. 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 comer of the site. A smaller ditch collects stormwater from the grinding area in the northeast comer 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 control structures effectively directed stormwater from the waste material during the first quarter 2011. 2.0 Groundwater Monitoring Program During the first quarter 2011 monitoring event, groundwater monitoring was performed at the French Camp Landfill by Del-Tech. Groundwater samples were collected from two background monitoring wells (MW-6A and MW-7A)and four detection monitoring wells(MW-8A,MW-9A, MW-913, and MW-10A) during the fast quarter 2011 monitoring event. The analytical results from samples collected at these wells are used to determine potential landfill-related impacts. The WDRs stipulate semi-annual sampling of the background monitoring wells and detection monitoring wells for field parameters (pH, specific conductance, temperature, and turbidity) and monitoring parameters(bicarbonate, calcium,carbonate, chloride,magnesium, nitrate,potassium, sodium, sulfate,TDS,and VOCs). The field results provided by Del-Tech and the laboratory results provided by TestAmerica for the first quarter 2011 groundwater monitoring event are summarized on Table 2.2. The historical groundwater data for the background and detection monitoring wells are presented in Appendix D. Times series concentration plots of historical groundwater data for the monitoring wells are presented in Appendix E. The concentration limits presented on Table 2.2 were calculated from background data collected through the third quarter 2010 monitoring event. The statistical analysis calculations for groundwater monitoring wells are presented in Appendix E. A copy of the statistical analysis methodology is presented in Appendix C. As presented on Table 2.2, the following constituents exceeded their respective concentration limits during the first quarter 2011: calcium at MW-913; chloride at MW-913; potassium at MW- 913; and field temperature at MW-10A. There were no VOCs detected at a groundwater monitoring wells during the first quarter 2011 monitoring event. Historical data from the groundwater monitoring wells were analyzed for temporal trends using Mann-Kendall / Sen's Slope trend analysis. Graphs and summary tables of the Mann-Kendall / Sen's Slope analyses for groundwater monitoring wells are presented in Appendix E. Chloride at MW-10A, potassium at MW-9B, and sulfate at MW-913 exhibited significant increasing statistical trends. Of these constituents, only potassium at MW-913 exceeded its concentration limit. Mann-Kendall / Sen's Slope analysis identified significant decreasing statistical trends in the following constituents: bicarbonate alkalinity at MW-8A, calcium at MW- 6A, chloride at MW-7A, magnesium at MW-6A and MW-8A, nitrate at MW-8A and MW-10A, field pH at MW-6A and MW-9B, field specific conductance at MW-7A, TDS at MW-7A and MW-8A, and field turbidity at MW-7A, MW-9A, and MW-10A. Given that field pH exhibits a significant decreasing statistical trend at upgradient well MW-6A, the decreasing trend for field pH at downgradient well MW-913 is likely due to ongoing changes in the natural groundwater geochemistry at the site.