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needed), and makes regular adjustments to the landfill gas extraction system to optimize efficiency of the landfill gas extraction system. The results of the 5 -year COC sampling conducted during the second quarter 2008 monitoring period indicates that excluding the metals, the following COCs were detected in groundwater and surface water samples at the Forward Landfill Unit: 2,4,5-T was detected above the PQL in the sample collected from well MW -2A; trace level concentrations of bis(2-ethylhexyl)phthalate were measured in the samples collected from wells MW -IA, MW -16, MW -17, MW -21, and MW -24; sulfide was detected above the PQL in the sample collected from well -24; cyanide was detected above the PQL in the sample collected from surface water station FSW-1; and a trace level concentration of cyanide was detected in the sample collected from surface water station FSW-2. Confirmation samples will be collected in August 2008 for each COC measured above a PQL including 2,4,5-T at well MW -2A, sulfide in well MW -24, and cyanide at surface water station FSW-1. In addition, MCL exceedces for the metals manganese and nickel were identified in several groundwater monitoring wells. However, considering the distribution of these detections and the relative immobility of metals in the neutral pH environments that exists at the Forward Unit, the metals results do not appear to reflect a landfill release to groundwater. 3.0 AUSTIN UNIT C 3.1.1 Sampling and Laboratory Analyses During the second quarter 2008, depth -to -water measurements were recorded in the groundwater monitoring wells on May 5, 2008 and the Austin Unit's DMP and CAP groundwater monitoring wells were sampled by ATC between May 5 and 8, 2008. Both surface water stations were sampled on May 6, 2008. A single sample set was collected from each sample point with sufficient liquid and submitted to BC for analysis of the parameters stipulated in RWQCB Order No. 85- 2003-0049. In addition, groundwater samples were analyzed for the full suite of COCs. Table 2-1 presents the monitoring schedule and summarizes the analytical methods utilized during the current monitoring period. Water quality samples were also analyzed in the field for dissolved oxygen, turbidity, temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells, surface water monitoring points, and leachate were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets, raw laboratory data, certificates of analyses, and chain -of -custody records related to the sampling program are included in Appendix C. The results of both field and laboratory analyses are summarized in Tables 3-1 through 3-6. D:\2008_0010\FA 2Q08.doc 9 Geologic Associates