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.0 Surface Water Monitoring • During the third quarter 2012 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 (p, 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 third quarter 2012 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. The concentration limits presented on Table 2.1 were calculated by Herst &Associates, Inc. from data collected through the third quarter 2012 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. As presented on Table 2.1, there were no constituents that exceeded their respective concentration limits at downstream monitoring point ASW -2 during the third quarter 2012 monitoring event. There were no VOCs detected above laboratory reporting limits (RLs) at the surface water monitoring points. 0 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. For constituents whose historical data consist primarily of non -detects (carbonate alkalinity and oil and grease), trend evaluation was performed on data from the earliest detection through the present. Wells with no historical detections for a constituent were not evaluated for trends. There were no constituents that exhibited a significant increasing statistical trend. Mann -Kendall / Sen's Slope analysis identified decreasing trends in the following constituents: COD at ASW -1, nitrate at ASW -1 and ASW -2, field specific conductance at ASW -1 and ASW -2, sulfate at ASW - 1 and ASW -2, TDS at ASW -1 and ASW -2, and TOC at ASW -1. 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 corner 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. During the third quarter 2012 monitoring event, groundwater detection monitoring and corrective action monitoring were performed at the Austin Road Landfill by Del -Tech. Monitoring well AMW-2, which is upgradient from the landfill, is the designated background well. Monitoring wells AMW-6, AMW-7, AMW-12, AMW-13, and AMW-14 are currently designated as