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• Grp 2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS On March 25, 2004, to comply with quarterly groundwater monitoring requirements, Ramage Environmental monitored and sampled two of the three wells Monitoring well MW-3 was not accessible, due to the presence of a parked car over the well 2.1 Groundwater Monitoring Depth-to-groundwater was measured in the two accessible wells to within 0 01-foot using a water level indicator The depth to the groundwater table ranged from 47 23 feet bgs in MW-2 to 47 50 feet bgs in MW-1 The corresponding groundwater surface elevations ranged from a high of 26 14 feet below mean sea level (msl) at MW-2 to a low of 26 24 feet below msl at MW-1 Since only two monitoring wells were accessible, a groundwater surface could not be derived, and groundwater flow and gradient characteristics could not be calculated The groundwater elevations and historical direction of groundwater flow are shown on Figure 3, and the groundwater monitoring data are summarized in Table 5 2.2 Groundwater Sampling and Analysis Following groundwater level measurements, the wells were purged and sampled The wells were purged with a pump and dedicated disposable tubing until at least three well casing volumes had been removed and/or after groundwater temperature, pH and electrical conductivity values had stabilized Groundwater was sampled from the wells using disposable polyethylene bailers and laboratory-supplied containers Each sample container was transported in an iced cooler with chain-of-custody documentation to Excelchem Environmental Labs (Excelchem), a state of California certified hazardous waste testing laboratory (#2119) Excelchem analyzed each sample for TPH-as-het fuel, TPH-as-gasoline and benzene, toluene, ethylbenzene, xylenes (BTEX) by EPA Method 8020/8015M, and for methyl tertiary butyl ether (MTBE), di-isopropyl ether (DIPE), ' ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), and tertiary butanol (TBA) by EPA Method 82608 The sample information field sheets are included in Appendix A The groundwater samples collected from both monitoring wells contained detectable concentrations of petroleum hydrocarbons Oxygenate compounds including MTBE were not detected in either well The groundwater sample analytical results are summarized in Table 4, the concentrations of petroleum hydrocarbons in groundwater are posted on Figure 4, and the laboratory reports are included in Appendix B 5