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2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS <br /> On February 17, 2000, Ramage Environmental monitored and sampled groundwater at the site. <br /> 2.1 Groundwater Monitoring <br /> Depth-to-groundwater measurements were taken in four groundwater monitoring wells to <br /> evaluate groundwater flow and gradient characteristics. Depth-to-groundwater measurements <br /> were not taken from MW-1 and the two deep soil vapor extraction wells (VW-1 and VW-2), <br /> because their wellhead elevations were moved during the installation of the soil vapor extraction <br /> and air sparging system. During this quarter, groundwater measurements were also not taken <br /> from MW-4 and MW-5 because their wellheads were blocked by the remediation system <br /> monitoring equipment. <br /> The depth-to-groundwater beneath the site ranged from 36.98 feet below ground surface (bgs) <br /> in MW-2 to 40.24 feet bgs in MW-7. MW-7 is completed above-grade and protected with a <br /> monument casing. The groundwater elevation beneath the site ranged from a high of 21.88 feet <br /> below mean sea level (MSL) in MW-2 to a low of 22.00 feet below MSL in <br /> MW-7. Groundwater levels have risen an average of 1.43 feet, since groundwater levels were <br /> last measured on November 12, 1999. In the past year, groundwater levels have dropped an <br /> average of 0.85 feet. Since May 1992, the groundwater levels have risen an average of 27.32 <br /> feet. The current and historical groundwater monitoring data are summarized in Table 1. <br /> The groundwater flow direction and gradient are illustrated on the groundwater surface map <br /> (Figure 3). The groundwater gradient was calculated at 0.001 foot/foot in a northeasterly <br /> direction. This is consistent with the historical prevailing groundwater gradient and flow <br /> direction. <br /> 2.2 Groundwater Sampling and Analysis <br /> Groundwater from MW-6, MW-7, Irrigation Well #2, and the two deep soil vapor extraction wells <br /> (VW-1 and VW-2) was sampled to evaluate the concentration of gasoline hydrocarbons at the <br /> groundwater table. The groundwater monitoring wells (MW-1, MW-2, MW-3, MW-4 and MW-5) <br /> were not sampled, because of groundwater levels significantly above the screened interval of <br /> these wells. <br /> �., 4 <br />