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1.0 Surface Water Monitoring During the first quarter 2010 monitoring event, surface water monitoring was performed at the Austin Road Landfill by Del-Tech Geotechnical Support Services, Inc. (Del-Tech). Littlejohns Creek was sampled at upstream (background) monitoring point ASW-1 and downstream monitoring point ASW-2. Surface water samples are scheduled to be analyzed quarterly for field parameters (pH, specific conductance, temperature, and turbidity) and monitoring parameters (bicarbonate, calcium, carbonate, chemical oxygen demand [COD], chloride, magnesium, nitrate, oil and grease, potassium, sodium, sulfate, total dissolved solids [TDS], total organic carbon [TOC], and volatile organic compounds [VOCs])when surface water is present. The field results provided by Del-Tech and 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. Times series concentration plots of historical surface water data are presented in 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 was calculated by Herst & Associates, Inc. using 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, Austin Road Landfill, prepared by CH2M Hill in January 2000. A copy of the statistical analysis methodology is presented in Appendix C. During the first quarter 2010 monitoring event, there were no constituents that exceeded their concentration limits at downstream monitoring point ASW-2. One VOC was detected at a surface water point during the first quarter 2010 monitoring event. Toluene was detected at downstream monitoring point ASW-2 at a concentration of 0.21 ug/L, which is above the laboratory method detection limit but below the reporting limit. Toluene has previously exhibited an unconfirmed detection at ASW-2 at concentration of 0.15 in November 2004. Toluene also exhibited an unconfirmed detection at upstream monitoring point ASW-1 at a concentration of 0.77 ug/L in August 2008. Historical data from the surface water monitoring points were evaluated for temporal trends using Mann-Kendall / Sen's Slope trend analysis. Graphs and summary table of the Mann-Kendall / Sen's Slope analyses for surface water monitoring points are presented in Appendix B. There were no constituents that exhibited a statistically significant upward trend. Mann-Kendall/Sen's Slope analysis identified decreasing trends in chemical oxygen demand at ASW-1, nitrate at ASW-1 and ASW-2, field specific conductance at ASW-1 and ASW-2, sulfate at ASW-2, TDS at ASW-1 and ASW-2, and TOC at ASW-1 and ASW-2. Site personnel reported that soil cover has been placed over the waste material to prevent ponding of stormwater and to protect surface water. In addition, down drains and a perimeter ditch direct stormwater to a basin in the southwest comer of the site. Inspection and maintenance procedures for these stormwater control structures are provided in the site's Stormwater Pollution Prevention Plan,prepared by CH2M Hill and revised June 1997. 2.0 Groundwater Monitoring During the first quarter 2010 monitoring event, groundwater detection monitoring and corrective action monitoring were performed at the Austin Road Landfill by Del-Tech. Monitoring well 1