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1 ARCADIS GERAGHTY&MILLER supply wells, and two sites as industrial water supply wells The nearest downgradient ' well (classified use is municipal)was reported to be located approximately 1,580 feet from the subject site Well search data were included in GSI's Well Installation Report (No 482721-2, October 21, 1997) As reported in the same document (Well Installation Report (No 482721-2, GSI, October 21, 1997), GSI installed off-site groundwater monitoring well U-9 in an attempt ' to delineate the downgradient edge of the dissolved plume Petroleum hydrocarbons were not detected in the three soil samples from the well boring that were submitted for ' analysis The groundwater sample from the well initially contained TPHg (990 ppb), benzene (130 ppb), and methyl tertiary butyl ether (MTBE) (12 ppb) Drilling and well ' installation data are presented in GSI's Well Installation Report (No 482721-2), dated October 21, 1997 Groundwater monitoring data collected November 10, 1998 indicate that momtonng well U-9 is nondetect for TPHg, BTEX, and MTBE Quarterly monitoring and sampling of the groundwater monitoring wells began in ' August 1994 At the time wells U-1 through U-3 were installed in August 1994, groundwater was measured at approximately 48 feet bgs Groundwater in well U-9 is ' currently measured at approximately 25 to 26 feet bgs (February 5, 1999), a rise of approximately 22 feet Groundwater flow direction during this period has been to the east-northeast The SJCPHS indicates that depth to water has been as deep as 70 feet bgs Dissolved concentrations of TPHg or benzene have been detected in wells U-1 through U- ' 4 and U-7 through U-9 The groundwater monitoring analytic data collected November 10, 1998, indicate that wells U-1 and U-3 contain dissolved concentrations of TPHg and ' benzene, but wells U-5 through U-9, which encompass upgradient, side gradient, and downgradient locations, were nondetect for TPHg and benzene ' 8