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15 March 2002 AGE-NC Project No 97-0249 Page 7 of 10 ' No other petroleum hydrocarbon constituents were detected by the laboratory analyses The laboratory reports (McCampbell Analytical Inc Lab ID's 84503-20, 84528-32 and 84745-51) and chain-of-custody forms are presented in Appendix B Analytical results of the ground water samples are summarized in Table 1, analytical results of CPT "grab" ground water samples collected in November 2001 are depicted in cross sectional views D-D', E-E' and F-F' (Figures 6, 7 and 8, respectively) 3.0 SUMMARY AND CONCLUSIONS ' The implications of the November 2001 CPT investigation results are as follows ' • Geologic cross sections D-D', E-E' and F-F' were generated from CPT data collected at borings P-10, P-11,P-12,P-13,P-16, P-17 and P-18 and depict general lithology beneath the site (Figures 3, 4 and 5, respectively) • Permeable to semi-permeable, gravelly sand, silty sand and fine to medium sand zones were generally encountered at depths between 35 and 55 feet bsg, 60 and 85 feet bsg, 90 and 105 feet bsg, 110 and 125 feet bsg and 135 to 145 feet bsg G Less permeable, stiff fine grained silt and clay zones were generally encountered at depths between 55 and 60 feet bsg, 85 and 90 feet bsg, 105 and 110 feet bsg and 125 feet to 135 feet bsg • It is not known how effectively the intervening fine grained intervals hydrologically separate the Informal hydrologic units, although laboratory analyzes of petroleum hydrocarbon-impact has migrated through or around them Geologic cross sections D-D', E-E' and F-F'depict the Informal hydrogeologic units and petroleum hydrocarbon concentrations beneath the site (Figures 3, 4, 5, 6, 7 and 8) AGE Interprets the CPT data to Identify six potential hydrologic units Informally named Hydrologic Unit No 1 located between 10 and 35 feet bsg, Hydrologic Unit No 2 located between 35 and 60 feet bsg, Hydrologic Unit No 3 located between 60 and 90 feet bsg, Hydrologic Unit No 4 located between 90 and 110 feet bsg,Hydrologic Unit No 5 located between 110 and 135 feet bsg and Hydrologic Unit No 6 located at depths greater than 135 feet bsg (Figures 3, 4 and 5) I • Hydrologic Unit No 1 at the site Is characterized by intense concentrations of fuel components, contaminants were detected in 10 of 11 water samples from HU-1 TPH-g has been detected in water samples at concentrations as high as 120,000 µg/1, TPH-d at concentrations as high as 490,000µg/l, benzene concentrations as high as 17,000µg/1 and 1,2-DCA at a concentration of 6 7 ,ug/l The core of the dissolved petroleum-hydrocarbon plume appears to be located between the Three B's Truck Plaza building and the former UST Advanced CeoEnvironmental,Inc I