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3 Ms. Margaret Lagorio April 15, 2003 Page 2 of 3 were collected using a 1.75-inch diameter core sampler lined with clear acetate sleeves. Soil was screened for the presence of volatile organic constituents (VOCs) using a photoionization detector (PID). Soil beneath the site consisted primarily of lean clay (CL) to silty clay (CL/MH), with some silty sand (SM, approximately 14-16 feet bgs) and elastic silt (MH, approximately 34- 36 feet bgs). Groundwater was initially encountered at a depth of approximately 34 feet bgs, but subsequently rose to approximately 32 feet bgs. No cuttings requiring disposal were produced. Barings were backfilled to the ground surface with neat cement grout. A soil boring log is included in Attachment 1. No petroleum hydrocarbon odors were noted during drilling. Soil samples collected at depths of approximately 15, 20, and 30 feet bgs were immediately capped and preserved in an iced cooler at a temperature of approximately 4° Centigrade for laboratory analysis. A discrete groundwater sample was also collected from the boring through temporary, 3/4-inch diameter PVC casing and screen. The groundwater sample was collected using a length of polytetrafloroethylene (PTFE) tubing equipped with a stainless steel bottom check valve. The tubing was inserted into the temporary casing and pushed down to the approximate center of the screened interval. The groundwater sample was brought to the surface by gripping the top of the tubing and rapidly moving the tubing up and down creating a positive displacement effect, thereby forcing the water sample to the surface. Approximately 1 liter of water was purged from the temporary casing prior to collecting the groundwater sample into 40-m1 glass vials, which were preserved with dilute hydrochloric acid. The sample containers were immediately placed into the cooler. LABORATORY ANALYSIS The soil and groundwater samples were submitted under chain of custody procedures to Argon Laboratories (ELAP #2359). The samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) by EPA method 8015M, for benzene, toluene, ethylbenzene, xylenes (BTEX) using EPA method 8021B, and for oxygenated gasoline additives and lead scavengers using EPA method 8260B. No gasoline constituents were detected above the method detection limits in the groundwater sample or any soil sample. Analytical results are summarized in Table 1. A copy of the laboratory report is included in Attachment 2. SUMMARY AND CONCLUSIONS Soil beneath the site is generally fine-grained (CL, CL/MII, SM, MH) from the ground surface to the water table. Groundwater was initially encountered at a depth of approximately 34 feet bgs, but rose to approximately 32 feet bgs immediately prior to collecting a groundwater sample. No gasoline constituents were detected in any soil or groundwater sample collected from boring SB 1. Based upon the results of soil and groundwater samples collected from boring SB 1, it does not appear that the low levels of gasoline previously detected in soil beneath the UST has impacted native soil or groundwater beneath the site. It is likely that previously detected contamination in the UST excavation resulted from minor overspillage during removal of the UST and associated piping. G\GROUNDZE\TheRecord\su etter.doc