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�,. The completed borings were backfilled to the ground surface with neat cement grout. No soil cuttings were generated. All down-hole drilling and sampling equipment was decontaminated by washing with a laboratory grade detergent and rinsing with water. Rinseate collected from decontamination procedures was disposed of via evaporation on the asphalt surface within the confines of the investigation area. Soil and groundwater samples were submitted under chain of custody procedures to Argon Laboratories for analysis. 4.0 RESULTS OF MVESTIGATION 4.1 Subsurface Conditions The uppermost 16 feet of the soil column in each of the borings consisted of silts and clays. In boring SB3 these fine-grained materials were underlain by clayey sand from a depth of approximately 18 feet to total depth of 31 feet. In boring SB4/SB4A clays and silts extended to a depth of approximately 28 feet where poorly graded sand was encountered and persisted to total depth of 51 feet. No petroleum odors or discoloration were noted in the samples collected from borings SBI through SB3 and SB5 through SBS. FID readings from these samples ranged from non-detectable levels to 1 part per million(ppm). Petroleum hydrocarbon odors characterized as slight were observed in samples collected from boring SB4/SB4A from the surface to a depth of approximately 40 feet. Within this interval, odors �.r were characterized as moderate between approximately 15 and 20 feet. SB4/SB4A had elevated readings on the FID,which ranged from a maximum of 500 ppm at 14-16 feet bgs to a minimum of 30 ppm at 40 feet, Below 40 feet FID readings were zero. 4.2 Laboratory Analysis Selected soil samples were analyzed for total petroleum hydrocarbons as gasoline(TPHg) and total petroleum hydrocarbons as diesel (TPHd) using EPA method 8015 modified. Benzene, toluene, ethylbenzene and xylenes (BTEX), methyl-cert-butyl ether (MTBE) and gasoline oxygenate additives were analyzed using EPA methods 8020 and 8260, respectively. Groundwater was analyzed for TPHg, TPHd, BTEX, MTBE and gasoline oxygenate additives by the methods listed above. 4.3 Sail Analytical Results The only soil sample with detectable contamination was collected from boring SB4 at a depth of approximately 15 feet bgs. This sample contained concentrations of TPHg and TPHd at 1.3 and 1,100 ppm, respectively. However, non-detectable levels were indicated for BTEX and gasoline oxygenate additives. In addition, it should be noted that the TPHg chromatogram did not snatch the typical gasoline pattern. Analytical results of soil samples are summarized in Table 1. Laboratory reports and chain of custody documentation are included in Attachment B woolrrydwtcAmporbUwnmmy-d= 4