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1.0 Surface Water Monitoring Surface water samples were collected by Bryan A. Stirrat & Associates during the third quarter 2006 monitoring event from Littlejohns Creek at the upstream 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 carbons [VOCs]) when surface water is present. The field and laboratory results provided by BC Laboratories, Inc. for the third quarter 2006 surface water monitoring event are summarized on Table 2.1. The historical surface water data are presented in Appendix A. The data are graphed on time series concentration plots, included in Appendix B. The concentration limits were calculated by Herst& Associates, Inc. using data collected through the third quarter 2006 monitoring event. Information on the development of the concentration limits can be found in the Fourth Quarter/Annual 1999 Monitoring Report, Austin Road Landfill prepared by C112M Hill in January 2000 and is also available in Appendix C of this report. The statistical analysis calculations for surface water monitoring points are included in Appendix B. During the third quarter 2006 monitoring event, only field pH exceeded its concentration limit at downstream surface water monitoring point ASW-2. The third quarter 2006 field pH value observed at ASW-2(9.5)is higher than values previously observed at that monitoring point. Table 2.1 presents the VOC detections at surface water monitoring points during the third quarter 2006 monitoring event. Bromoform was detected at surface water monitoring point ASW-2 at a concentration of 1.2 ug/L. Dibromochloromethane was detected at surface water monitoring point ASW-2 at a concentration of 0.55 ug/L, and at surface water monitoring point ASW-1 at a concentration (0.33 ug/L) below the laboratory practical quantitation limit (PQL). Neither bromoform nor dibromochloromethane exhibits an increasing trend according to Sen's Slope analysis. The broinoform and dibromochloromethane detections at ASW-1 and ASW-2 during the third quarter 2006 are the first detections of these constituent at surface water monitoring points. Historical data from the surface water monitoring points were evaluated for temporal trend using Sen's Slope trend analysis. Graphs of the Sen's Slope analyses for surface water monitoring points are included in Appendix B. Only field pH at ASW-2 exhibited a statistically significant upward trend for the third quarter 2006 monitoring event. The third quarter 2006 field pH value observed at ASW-2 (9.5) is higher than values previously observed at that monitoring point. Sen's Slope analysis identified decreasing trends in nitrate at ASW-2, field specific conductance at ASW-1, total dissolved solids at ASW-1 and ASW-2, and total organic carbon at ASW-1 and ASW-2. Site personnel report 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. 1