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I 25 March 2002 AGE-NC Project No 97-0326 IPage 7of9 HU5 One ground water sample; was collected from HU5 (CPT-5), TPH-g (1,500 µg/1) and BTEX compounds (12 µg/1 benzene, 74 µg11 toluene, 52 µg/l ethylbenzene and 240 µg/1 xylenes) were detected In addition, 'MTBE was detected at a concentration of 12 µg/1 1 HU6 Ground water samples were collected within HU6 from CPT-4 and CPT-5, TPH-g and BTEX compounds were detected in both samples The highest concentrations of TPH-g(89 µgll), `oluene (15 µg/1), ethylbenzene (2 5 4g/1) and xylenes (9 3 µg/1)were detected in the sample from CPT-5, the highest benzene concentration(8 1 µg/1)was encountered in the sample from CPT-4 In addition. MTBE (1 3 4g11) was detected from the sample from CPT-4 I No other petroleum hydrocarbon constituents or fuel oxygenated compounds were detected in ground water or soil samples by the laboratory analyses The laboratory reports (MAI Lab I D 82829 through 82832 and 83352 through 83354)and chain-of custody forms are presented in Appendix B Analytical results of the CPT grab ground water samples from the 02 and 07 November 2001 survey, as well as the CPT soil and grab ground water samples from the 14 and 15 February 2001 survey, are summarized In Tables 1 and 2 4.0. SUMMARY AND CONCLUSIONS The implications of the combined February 2001 and November 2001 CPT Investigations results are as follows The more permeable llthology encountered during the CPT Investigation consists of laterally discontinuous lenses of fine to coarse sand at depths between 19 and 24 feet bsg and at approximately 34 feet bsg in the western portion of the site and continuous sand layers at depths of between78 and 85 feet bsg, 108 to 120 feet bsg and below 136 feet bsg Lithologles with variable permeability include stiff fine-grained sediment and cemented sands Silts, silty fine sand and sandy silt tend to have moderate permeability, whereas clay, silty clay and clayey silt tend to be the lease Ipermeable I AGE Interprets the CPT data to Identify a vadose zone and six hydrogeologic uruts(HUs) at the site The second, fourth and sixth HUs, which contained sandy intervals, are Inferred to be high Advanced GeoEnvironmentai Inc I