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exceeding DHS MCLS Groundwater samples collected from monitoring <br /> well MW-4 contained 3 8 ppb benzene and 43 ppb MTBE Groundwater <br /> samples collected from monitoring well MW-3 contained 12 ppb MTBE <br /> and 44 ppb TBA Groundwater samples collected from downgradient <br /> monitoring wells MW-13 and MW-14 contained 490 ppb and 38 ppb <br /> MTBE, respectively The groundwater sample collected from monitoring <br /> well MW-13 also contained 100 ppb TBA Groundwater samples collected <br /> 1 from shallow monitoring wells MW-1, MW-2 and MW-15 did not contain <br /> concentrations of any compound above DHS MCLS for drinking water <br /> None of the wells screened below 19-feet bgs contained any compound at <br /> concentrations exceeding DHS MCLS However, various compounds were <br /> detected in groundwater samples collected from all of these wells at <br /> concentrations below DHS MCLs including MTBE, TBA, PCE and 1 ,2- <br /> dichloropropane In addition, ethanol was detected in groundwater <br /> samples collected from three of these deeper wells The highest ethanol <br /> concentration was 58,000 ppb in the groundwater sample collected from <br /> monitoring well MW-12 <br /> Groundwater to the shallow zone (less than 19-feet bgs) appeared to flow <br /> primarily to the northwest beneath the site at a gradient of approximately <br /> 0 012-feet/foot Groundwater in the 55-feet bgs to 70-feet bgs zone <br /> flowed to the east at a gradient of 0002-feet/foot <br />' 2-12 Jilly. - August and September ,.24,0,() _Domestic Well Sampling <br /> Between July and September 2000, ASE collected groundwater samples <br /> from 38 domestic and 2 irrigation wells in the site vicinity Ten domestic <br /> wells and one irrigation well north of the site have detectable MTBE <br /> concentrations as high as 82 ppb In addition, two additional wells have <br /> concentrations of 1,2-dichloroethane (1,2-DCA) but do not have <br /> concentrations of MTBE <br /> 3August 2000 Feasibility Tests, and Interim Remediation System <br /> Worknl an <br /> In August 2000, ASE installed one extraction and one air sparge well at the <br /> site ASE also conducted a step drawdown pumping test, a constant rate <br /> pumping test, an air sparging test and a dual-phase extraction test at the <br /> site Results of these feasibility tests can be found in ASE's workplan titled <br /> "Workplan for the Installation of an Interim Remediation System" dated <br /> September 5, 2000 <br /> Franks One Stop Report — November 2000 <br /> 1 -6- <br />