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1.0 Surface Water Monitoring
<br /> Surface water samples at the Austin Road Landfill were collected by ATC Associates, Inc. during
<br /> the third quarter 2008 monitoring event from Littlejohns Creek at the upstream monitoring point
<br /> (ASW-1) and downstream monitoring point(ASW-2). Surface water samples are scheduled to be
<br /> analyzed quarterly for field parameters(pH, specific conductance,temperature, and turbidity) and
<br /> monitoring parameters (bicarbonate, calcium, carbonate, chemical oxygen demand [COD],
<br /> chloride, magnesium, nitrate, oil and grease, potassium, sodium, sulfate, total dissolved solids
<br /> [TDS],total organic carbon [TOC],and volatile organic compounds [VOCs])when surface water
<br /> is present.
<br /> The field results provided by ATC Associates, Inc. and laboratory results provided by BC
<br /> Laboratories, Inc. for the third quarter 2008 surface water monitoring event are summarized on
<br /> Table 2.1. The historical surface water data are presented in Appendix A. The data are graphed
<br /> on time series concentration plots, included in Appendix B. The concentration limits were
<br /> calculated by Herst & Associates, Inc. using data collected through the third quarter 2008
<br /> monitoring event. Information on the development of the concentration limits can be found in the
<br /> Fourth Quarter/Annual 1999 Monitoring Report, Austin Road Landfill, prepared by CH2M Hill
<br /> in January 2000. A copy of the statistical analysis methodology is included in Appendix C. The
<br /> statistical analysis calculations for surface water monitoring points are included in Appendix B.
<br /> During the third quarter 2008 monitoring event, bicarbonate alkalinity, calcium, chloride,
<br /> magnesium, potassium, sodium, sulfate, and total dissolved solids exceeded their concentration
<br /> limits at downstream monitoring point SW-2.
<br /> One VOC was detected at a surface water monitoring point during the third quarter 2008
<br /> monitoring event. Toluene was detected at upstream monitoring point ASW-1 at a concentration
<br /> of 0.77 ug/L. There were no VOCs detected at downstream monitoring point ASW-2. The
<br /> toluene detection at ASW-1 is the first detection of this constituent at this monitoring point.
<br /> Historical data from the surface water monitoring points were evaluated for temporal trend using
<br /> Sen's Slope trend analysis. Graphs of the Sen's Slope analyses for surface water monitoring
<br /> points are included in Appendix B. There were no constituents that exhibited a statistically
<br /> significant upward trend. Sen's Slope analysis identified decreasing trends in chemical oxygen
<br /> demand at ASW-1, nitrate at ASW-2, field specific conductance at ASW-1, TDS at ASW-1 and
<br /> ASW-2, and TOC at ASW-1.
<br /> Site personnel reported that soil cover has been placed over the waste material to prevent ponding
<br /> of stormwater and to protect surface water. In addition, down drains and a perimeter ditch direct
<br /> stormwater to a basin in the southwest corner of the site. Inspection and maintenance procedures
<br /> for these stormwater control structures are provided in the site's Stormwater Pollution Prevention
<br /> Plan,prepared by CII2M Hill and revised June 1997.
<br /> 2.0 Groundwater Monitoring
<br /> Groundwater samples were collected by ATC Associates, Inc. during the third quarter 2008
<br /> monitoring event from the detection monitoring and corrective action wells at the site.
<br /> Monitoring well AMW-2, which is upgradient from the landfill, is the designated background
<br /> well. Monitoring wells AMW-6, AMW-7, AMW-12, AMW-13, and AMW-14 are currently
<br /> designated as detection monitoring wells. Monitoring wells AMW-1, AMW-3, AMW-4, AMW-
<br /> 5R,AMW-10,AMW-11, AMW-18, and AMW-19 are designated as corrective action monitoring
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