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i .1 II S subsurface utilities An access entry agreement had not been reached with the private property Mowner for that work at the time of the drilling, consequently additional borings were not advanced on the Delta Disposal property All drilling equipment and sampling tools were cleaned prior to arriving, and before leaving the site 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 lithologic information was collected to describe the subsurface geology Soil samples were field screened for petroleum soil vapor using a photoiomzation vapor meter calibrated to the manufacturers specifications Soil samples were collected at minimum five-foot intervals, at intervals of apparent obvious contamination and/or 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 borehole sealing process as well as portions of the drilling and sampling work Groundwater Samples Each exploratory boring was sampled The ground water samples collected from the boreholes were 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 in some boreholes were made to the nearest one- one hundredth of one foot to the surface grade, and also checked for the presence of separate phase product The water entering the borehole was sampled using a clean disposable bailer or downhole sampling tube, and carefully poured into the appropriate laboratory prepared container with m,mmum 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 Conditions Three borings were advanced in the public right of way in front of the referenced site Borings B-1 and B-2 were advanced through the asphalt patches assumed to correspond with the former tank pit locations The borings revealed sandy clay and sandy silt to depths of nine to 14 feet below surface grade A sequence of interbedded sand, sandy clay and clayey sand under the clay and silt strata to depths of 19 to 24 feet. These strata compose the uppermost aquifer strata Clayey salad and silty clay underlie the aquifer strata These clayey strata appear laterally discontinuous in the general area of the site investigation (see Figure 1) Groundwater occurs at depths of 15 5 to 16 feet and appeared to be unconfined however boreholes were not open long efi,o4gh to allow for 24 hours of stabilization for additional groundwater measurements • Page 2 of 6 t