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' 28 July 2003 <br /> • AGE-NC Project No 95-0184 <br />' Page 4 of 5 <br />' • Ground water elevations at the site averaged approximately 2176 feet below MSL All <br /> ground water wells except VW-3,VW-4 and VW-5B were"drowned",with water levels as <br /> high as 20 feet above the screened intervals of the drowned wells <br />' • The ground water was inferred to flow generally northeast across much of the site at a <br /> gradient of approximately 0 004 to 0 007 feet/feet This ground water flow direction is <br />' consistent with the last twenty-one monitonng events (Table 4) <br /> • Detectable concentrations of TPH-g were found in all of the ground water wells sampled <br />' One or more BTE&X compounds were found in all ground water samples collected These <br /> samples contained one or more analytes at concentrations above California's Maximum <br /> Contaminant Levels (MCLS) <br />' • No free product was measured during this sampling event,however,most of the well screens <br /> are drowned and are not likely to produce direct evidence of free product <br />' • MTBE was detected in samples from wells MW-4, VW-2B, VW-3 and VW-4 at <br /> concentrations ranging from 81 µg/1 to 850 µg/1 1,2-DCA and EDB were detected multiple <br /> wells,at concentrations ranging from 8 2µg/1 to 350µg11 The concentrations of MTBE, 1,2- <br /> DCA and EDB in.the ground water samples exceed the MCLS for drinking water <br /> • Naththalene, 1,2,4-tnmethylbenzene, 1,3,5-tnmethylbenzene and n-propylbenzene were <br /> detected in ground water samples at concentrations above the DHS-recommended drinking <br /> water Action Levels <br /> • The vertical and lateral extent of impacted soil and ground water has not yet been defined <br /> I <br />' 5:0. RECOMMENDATIONS <br /> Based upon data collected from the site, AGE recommends <br /> • Continued quarterly ground water monitoring The third quarter 2003 monitoring event <br /> should be performed in September 2003 <br /> • AGE is currently preparing a work plan to further delineate the vertical and lateral extent of <br /> impacted ground water on- and off-site as requested in a meeting with the EHD on <br /> 12 June 2003 <br /> I <br /> Advanced GeoEnviranmental,Inc <br />