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2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS r� On August 28, 2008, to comply with quarterly groundwater monitoring requirements, Ramage Environmental monitored and sampled the three wells for the final time. �. 2.1 Groundwater Monitoring To calculate the groundwater gradient and flow direction, Ramage Environmental measured w depth-to-groundwater in all three wells using a water level indicator. The depth-to-groundwater beneath the site ranged from 9.12 feet bgs in MW-3 to 9.56 feet bgs in MW-1. The groundwater 0.6 elevation beneath the site ranged from a high of 39.82 feet above mean sea level (msl) in MW-1 to a low of 39.65 feet above msl in MW-3. The resulting groundwater surface appears as a regular plane dipping toward the north-northwest at a gradient of approximately 0.0026 foot/foot. La A groundwater surface contour map is included as Figure 3, and the groundwater monitoring data are summarized in Table 2. LA Between June 30, and August 28, 2008, the groundwater elevation in the three monitoring wells dropped an average of 0.44 feet, the gradient increased from 0.0022 to 0.0026 foot/foot, and the groundwater flow direction remained toward the north. These groundwater surface characteristics are consistent with historical and seasonal trends. 2.2 Groundwater Sampling and Analysis Following groundwater level measurements, Ramage Environmental purged and sampled all three monitoring wells. The wells were purged using a pump and dedicated disposable tubing, LO 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 B. Following well purging and recharge, Ramage Environmental sampled groundwater from the to wells using dedicated disposable bailers and laboratory-supplied containers. The groundwater samples were transported in an iced cooler with chain-of-custody documentation to Exceichem Environmental Labs (Exceichem), a state of California certified hazardous waste testing 4 laboratory (Certification #2119). Excelchem analyzed each of the groundwater samples for TPH-as-diesel by EPA Method 8015M, TPH-as-gasoline, and BTEX by EPA Method �.+ 8021 B/801 5M, and for methyl tertiary butyl ether (MTBE), di-isopropyl ether (DIPS), 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 82606. ,� 7