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MW-3, the sand layer was encountered between approximately 38 feet and 48 feet bgs In boring MW-4, it was present from about 41-48 feet bgs A relatively fock(greater than 30 feet) layer of silt and sandy silt is present from approximately 1 60 feet bgs to at least 90 feet bgs in the vicinity of MW-2, MW-3, and MW-4 A similar, but sandier unit is present in the vicinity of MW-1 and boring B-2 from about 45 feet to 80 feet bgs In Bonng B-2, this silt unit graded into silty sand at 75 feet bgs In MW-1, the silt graded into ' silty sand at about 85 feet bgs Field evidence (OVM and olfactory) of petroleum hydrocarbon-impacted soil was noted in MW-1, MW-2, and B-2 in soil samples from the sand layer between about 35 feet and 45 feet bgs, then again from about 60 feet bgs to groundwater Soil samples from near groundwater in MW-4 also registered low OVM readings Analytical results for soil samples showed detectable concentrations of petroleum hydrocarbons in samples from borings B-2 and MW-2 Analytical results for the soil samples are summarized in Table 1 4.2 Groundwater Groundwater was encountered at 79-88 feet bgs and stabilized at approximately 70 feet bgs within about three hours after drilling The groundwater elevation in monitoring well MW-1 was about 2-2 5 feet lower than groundwater elevations in MW-2,MW-3, and MW-4 Groundwater elevation data for the Site indicates that groundwater flow in the vicinity of the monitoring wells is to the east-southeast with a steepening gradient Groundwater elevation data is presented in Table 3 A Potentiometnc Surface Map for February 1999 is presented as Figure 3 Laboratory analyses showed consistently detectable concentrations of petroleum hydrocarbons in groundwater samples from monitoring wells MW-1, MW-2, and MW-4 Petroleum hydrocarbons were also detected in the Hydropunch® groundwater sample obtained from Boring B-2 Benzene was detected in the uutial groundwater sample from monitoring well MW-3, but none of the analytes were detected in the second groundwater sample obtained from that well 4.3 Domestic Well A Department of Water Resources Water Well Drillers Report indicates the following construction details for the domestic well at the Site Date of Construction 8121/81 Total Depth 215 feet Screened Interval 195-215 feet Gravel Pack 50-215 Feet Petroleum hydrocarbons were not detected in water samples obtained from the domestic well on 3/7/97, 1/8/99, and 2/5/99 Interim Report-07400178-May 1999 5