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u N • All drilling equipment and sampling tools were cleaned prior to arriving, and before leaving the site The probe was advanced collecting continuous cores of soil in borehole B-1 and interval sampling in the remaining boreholes The sampler was retrieved and dissembled, and the soil filled acetate liner was sealed with Teflon paper or foil and plastic endcaps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest on crushed ice Soil sample intervals retained for chemical analysis were cut from the liners at depths of suspected contaminant presence The boreholes were logged using the Unified Soil Classification System under the supervision of a registered geologist Additional llthologic information was collected to describe the subsurface geology Soil samples were field screened for petroleum soil vapor using a photoionization vapor meter calibrated to the manufacturers specifications interval samples were collected at five-foot intervals, at intervals of obvious contamination and at stratigraphic features of interest Upon completion of the borehole drilling and collection of water samples, all boreholes were backfilled with grout, placed from the bottom to top of the borehole and a PHS EHD representative witnessed the process Groundwater Sam lm Each exploratory boring was sampled The ground water samples collected from the boreholes was used for a reconnaissance of the site groundwater contamination A brief summary of these procedures follows Each borehole was advanced into the aquifer and temporarily cased for sampling Depth to groundwater measurements were made to the nearest one-one hundredth of • one foot, and also checked for the presence of separate phase product The water entering the borehole was sampled using a clean bailer, and carefully poured into the appropriate laboratory prepared container with minimum cavitation Each water sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest for transport to the laboratory Subsurface Conditwons Four bonngs were advanced on the site The borings revealed silty clay to depths of about nine to 15 feet Boring B-4 was drilled through the former tank pit and revealed silty gravel backfill , to a depth of nine feet and underlain by sandy clay to a depth of 14 feet The clay strata are underlain by sandy silt, clayey sand and sand to depths of about 16 to 20 feet, and appear to grade ' laterally with each other A clay stratum underlies the sandy strata The clayey stratum appears laterally continuous in the general area of the site investigation (see Figure 1) Groundwater occurs at depths of 13 to 14 feet and initially stabilized in uncased boreholes at depths of 8 7 to 11 9 feet Groundwater appears to be unconfined to slightly confined however boreholes were not open long enough to allow for 24 hours of stabilization for additional groundwater measurements • Page 2 of 6