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2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS On June 22, 2006, Ramage Environmental monitored and sampled the three wells 2.1 Groundwater Monitoring Depth-to-groundwater was measured in all three wells using a water level indicator The depth- to-groundwater beneath the site ranged from 7 98 feet bgs in MW-3 to 8 41 feet bgs in MW-1 The groundwater elevation beneath the site ranged from a high of 40 97 feet above mean sea level (msl) in MW-1 to a low of 40 79 feet above msl in MW-3 The resulting groundwater surface appears as a regular plane dipping to the north-northwest at a gradient of approximately 0 003 foot/foot A groundwater surface contour map is included as Figure 3, and the groundwater monitoring data are summarized in Table 1 22 Groundwater Sampling and Analysis Fallowing groundwater level measurements, all three wells were purged and sampled The wells were purged using a pump and dedicated disposable tubing, until at least three well casing volumes were extracted and/or after groundwater temperature, pH and electrical conductivity values had stabilized The sampling information field sheets are included in Appendix A Following well purging and recharge, groundwater was sampled from the wells using dedicated disposable bailers and laboratory-supplied containers The groundwater samples were transported in an iced cooler with chain-of-custody documentation to Excelchem Environmental Labs (Excelchem), a state of California certified hazardous waste testing laboratory (Certification #2119) Excelchem analyzed each of the groundwater samples for TPH-as-diesel by EPA Method 8015M, and for TPH-as-gasoline, BTEX, methyl tertiary butyl ether (MTBE), di-isopropyl ether (DIPE), tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), tertiary butanol (TBA), 1,2-dichloroethane (1,2-DCA), and 1,2-dibromoethane (EDB) by EPA Method 8260B The groundwater samples from all three of the monitoring wells did not contain reportable concentrations of petroleum hydrocarbon compounds The groundwater analytical results are summarized in Table 2, and posted on Figure 4 The laboratory reports are included in Appendix B 5