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,* CAMBRIA lateral extent of impacted soil is limited to the northern fuel dispenser area Low levels of gasoline constituents detected in deeper soil samples from this boring are likely due to impacted groundwater found at depth The highest levels of gasoline constituents detected in groundwater samples during this investigation were from the 72 fbg sample from boring SB-8 These findings correlate well with the data from boring SB-4 (December 1999 investigation) It appears that petroleum hydrocarbons in groundwater in the vicinity of the suspected source area have migrated northwest to the location of boring SB-8 Groundwater samples collected from boring SB-7, located west of the northern fuel dispenser contained only low concentrations of TPHg and no BTEX These data suggest there has been little impact to groundwater west of the suspected source area Groundwater samples collected from boring SB-9, located south of the northern fuel dispenser, also contained low levels of TPHg and no BTEX These data suggest there has been only minor groundwater impact south of the suspected source area Groundwater samples collected from SB-10 contained TPHg at each depth interval, but BTEX only at the 82 fbg sample These data suggest impacted groundwater, • located at approximately 82 fbg, has migrated southeast -of the suspected source area Groundwater samples from SB-11 did not contain TPHg or BTEX with the exception of 63 ppb of TPHg at 82 fbg These data suggest the lateral extent of impacted groundwater is delineated to the east of the suspected source area Groundwater samples collected during this investigation did not contain MTBE with the exception of one low level detection(2 8 ppb) in SB-11 at 95 fbg These data are consistent with previous findings at this site, which indicate there is little MTBE in soil and groundwater beneath this site The absence of MTBE in the soil and groundwater suggests that the release at this site is old and likely occurred prior to the introduction of MTBE into gasoline Low levels of fuel oxygenates (other than MTBE) were detected in groundwater samples collected from the soil borings during this investigation The presence of these fuel oxygenates appears anomalous due to the absence of MTBE in groundwater at this site and the fact that the fuel oxygenates were not detected in soil samples Typically MTBE is the predominant fuel oxygenate in Shell gasoline, and other oxygenates may be present at lower percentages as impurities The fuel oxygenates detected at this site should normally be accompanied by higher levels of MTBE in the groundwater MTBE was not detected in any of the groundwater samples collected during this investigation except for one sample, which contained 2 8 ppb Soil samples collected during this investigation and from previous investigations have not contained MTBE or any of the other fuel oxygenates If fuel oxygenates are present in deep groundwater beneath the 0797 6