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CLEARWATER G R O U P, I N C 1 the basisf o water levels and survey measurements obtained on December 14, ' 1995 The groundwater flow direction on the MBP site appears to be toward the ' southeast, at a gradient of approximately 0 003 foot/foot (0 30%). On the basis of water levels measured by Geocon, the groundwater flow direction on the east side of the FDIC site is south to southwesterly, with a groundwater gradient of 12-14% in the vicinity of the former pump islands 4.2 Analytical Results of Groundwater Samples The results of groundwater analyses are included in Table 1, and Figure 4 presents the results of TPHg, benzene, and MTBE analyses TPHg, BTEX, and ' MTBE were detected in concentrations exceeding method detection limits in water samples collected from both MBP monitoring wells BMW-1 and BMW-2. TPHd was also detected in both samples, although laboratory ' qualifiers indicate that the chromatograph patterns did not match the pattern of the diesel fuel standard In general, the highest concentrations of analytes were detected in the groundwater sample from BMW-1 Maximum concentrations of TPHg, benzene, and TPHd in the BMW-1 sample were 1,400 ppb, 68 ppb, and 340 ppb, ' respectively MTBE concentrations were 91 ppb and 200 ppb in samples from BMW-1 and BMW-2, respectively No analytes were detected in the trip blank or in the equipment blank A comparison of groundwater analytical data from the FDIC monitoring ' wells indicates that the highest concentrations of TPHg and BTEX on the FDIC ` site were in the groundwater sample from MW-2, located immediately downgradient of the former pump islands The MW-2 sample contained 790 ' ppb TPHg, 88 ppb benzene, and 9 ppb MTBE The maximum MTBE concentration was detected in the sample collected from monitoring well MW-1, located near the western site boundary 1 1 C-115 4Qtr 95 2/96 ¢