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and soil was excavated from the tank pit and dispensers areas during tank removal and was <br /> subsequently returned to the tank pit as fill. <br /> Field Methods <br /> Exl2loratory Borings <br /> Six exploratory borings were drilled at the locations shown on Figure 1. Drilling permits were <br /> secured from PHS EHD, and a utility clearance was performed prior to doing the fieldwork. The <br /> boreholes were drilled with GeoProbe truck mounted drilling equipment. Boring locations were <br /> adjusted in the field due the proximity of numerous subsurface utilities. <br /> All drilling equipment and sampling tools were cleaned prior to arriving, between boreholes and <br /> before leaving the site. The sampler was retrieved and dissembled, and the soil filled acetate liner <br /> retained for analysis was sealed with Teflon paper or foil and plastic endcaps, labeled, logged <br /> onto chain-of-custody forms and place in a chilled ice chest on crushed ice. Soil sample intervals <br /> retained for chemical analysis were cut from the liners at depths of suspected contaminant <br /> presence or interest. <br /> The boreholes were logged using the Unified Soil Classification System under the supervision of <br /> a registered geologist. Additional lithologic information was collected to describe the subsurface <br /> geology. Soil samples were field screened for petroleum soil vapor using a photoionization vapor <br /> meter calibrated to the manufacturers specifications. Interval samples were collected at <br /> minimum five-foot intervals, at intervals of suspected contamination and at stratigraphic features <br /> of interest. Upon completion of the borehole drilling and collection of water samples, all <br /> boreholes were backfilled with grout, placed from the bottom to top of the borehole and a PHS <br /> EHD representative witnessed the sealing process and portions of the drilling and sampling. <br /> Groundwater Sampling <br /> Each exploratory boring was sampled. The ground water samples collected from the boreholes <br /> were used for a reconnaissance of the site groundwater contamination. A brief summary of these <br /> procedures follows: Each borehole was advanced into the aquifer and temporarily cased for <br /> sampling. Depth to groundwater measurements were made to the nearest one-one hundredth of <br /> one foot, and also checked for the presence of separate phase product. The water entering the <br /> borehole was sampled using a clean disposable bailer or downhole sampling tube, and carefully <br /> poured into the appropriate Iaboratory prepared container with minimum cavitation. Each water <br /> sample was labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest for <br /> transport to the laboratory. <br /> Subsurface Conditions <br /> Six borings were advanced on the site. Boring B-3 was continuously cored adjacent to the <br /> former tank pit. The borings revealed sandy clay and sandy silt to depths of nine to 14 feet below <br /> surface °rade. A sequence of interbedded sand. sandy clay and clayey sand under the clay_ and <br /> Page 2 of 8 <br /> i <br />