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2.0 GROUNDWATER MONITORING, SAMPLING AND ANALYSIS <br /> On May 19, 2000, Ramage Environmental monitored and sampled groundwater at the site <br /> 21 Groundwater Monitoring <br /> Depth-to-groundwater measurements were taken in three groundwater monitoring wells (MW-3, <br /> MW-6 and MW-7) to evaluate groundwater flow and gradient characteristics Depth-to- <br /> groundwater measurements were not taken from MW-1 and the two deep soil vapor extraction <br /> wells (VW-1 and VW-2), because their wellhead elevations were moved during the installation of <br /> the soil vapor extraction and air sparging system During this quarter, groundwater <br /> measurements were also not taken from MW-4 and MW-5 because their wellheads were <br /> blocked by the remediation system monitoring equipment In addition, MW-2 could not be <br /> located under construction debris, and was not monitored <br /> In the three wells monitored, the depth-to-groundwater beneath the site ranged from 34 52 feet <br /> below ground surface (bgs) in MW-3 to 37 45 feet bgs in MW-7 MW-7 is completed above- <br /> grade and protected with a monument casing The groundwater elevation beneath the site <br /> ranged from a high of 19 12 feet below mean sea level (MSL) in MW-3 to a low of 19 21 feet <br /> below MSL in MW-7 Groundwater levels have risen an average of 2 77 feet, since groundwater <br /> levels were last measured on February 17, 2000 In the past year, groundwater levels have <br /> risen an average of 0 13 feet Since May 1992, the groundwater levels have risen approximately <br /> 32 5 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 0017 foot/foot in a northeasterly <br /> direction This is consistent with the prevailing historical groundwater gradient and flow <br /> direction <br /> 22 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 />