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decontaminated, %-inch stainless steel or %-inch-diameter disposable polyethylene bailers. Groundwater was transferred from the bailer by inserting a bottom -emptying device into the base of the bailer and slowly discharging the sample into laboratory - provided 40 -milliliter glass containers (VOAs) with hydrochloric acid preservative. Samples and a travel blank were transferred to the laboratory courier under strict chain - of -custody protocols, and were analyzed for volatile organic compounds (VOCs) according to EPA Method 8260B by BC Laboratories, Inc. (BC) of Bakersfield, California. Samples from the temporary wells yielded the following results: Note: A trace concentration is one measured between the laboratory's Method Detection Limit (MDL) and Practical Quantitation Limit (PQL). No VOCs were detected in the travel blank or laboratory method blank. To verify these finding, the County directed GLA to collect a second set of samples. Groundwater elevations were measured, and groundwater samples were collected from each of the three temporary wells on November 2, 2011. The results of the second tests were similar to the first, as follows: Well ID VOC Concentrations From Samples Taken October 13 and 19, 2011 L) Dichlorodifluoromethane Tetrachloroethene Trichlorofluoromethane Well ID (DCDFM) (PCE) (TCFM) Total VOC VOC Concentrations from samples taken November 2, 2011(µg/L) DCDFM PCE TCFM Total VOC MW -9 2.1 0.32 (trace) 0.61 3.03 MW -10 0.21 (trace) 0.66 0.22 (trace) 1.09 MW -11 1 2.8 1.6 1 0.16 (trace) 4.56 Note: A trace concentration is one measured between the laboratory's Method Detection Limit (MDL) and Practical Quantitation Limit (PQL). No VOCs were detected in the travel blank or laboratory method blank. To verify these finding, the County directed GLA to collect a second set of samples. Groundwater elevations were measured, and groundwater samples were collected from each of the three temporary wells on November 2, 2011. The results of the second tests were similar to the first, as follows: Well ID Groundwater Elevation (ft) VOC Concentrations from samples taken November 2, 2011(µg/L) DCDFM PCE TCFM Total VOC MW -9 230.77 2.6 0.66 1.5 4.76 MW -10 220.06 0.52 0.88 0.40 (trace) 1.8 MW -11 216.57 2.9 1.3 0.15 (trace) 4.35 No VOCs were detected in the travel blank or laboratory method blank. These results verify the preliminary sample results and suggest a northeasterly migration of VOCs from the CHSL. Laboratory data and chain -of -custody documentation for the preliminary and verification sample sets are provided in Appendix 2. EMP Report— Phase IGeo-Loic Page ■ 8 Corral Hollow Sanitary landfill ASS O C 1 ATE SS February 1, 2012