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' oealogWAI Tedhnks lnc Page 8 Site Charactenzation Report ' Project No 724 2 May 9, 2006 Nate The cross sections were developed using data gathered by different individuals ' utilizing different methodologies Therefore, they need to be looked at as one of several possible interpretations of actual site conditions ) ' 3.2 Contaminant Distribution The next two sections summarize the results of the laboratory analyses for the soil and ' groundwater samples obtained during this field mobilization Figures 5 & 7 illustrate the soil contaminant distribution superimposed on cross sections A - A' and B — B' The two figures also include the January 17, 2006 groundwater data and February 2006 CPT data ' superimposed next to the borings and well screens Tables 1, 2, 3 & 5 in Appendix A contains the site's historical soil, groundwater and CPT ' boring analytical data 3.2.1 Soil ' No field evidence of soil contamination was noted in the boreholes GTI's work plan called for a minimum of the capillary fringe samples to be obtained from each CPT location for laboratory analysis A single soil sample (two from CPT-2) were obtained in each CPT borehole from at or dust below the capillary fringe (groundwater 32 5 feet bgs) None of the soil samples from boreholes CPT-1, CPT-2 and CPT-3 contained contaminant concentrations ' above the laboratory reporting limits 3.2.2 Groundwater One or two groundwater samples were obtained from each borehole to complete vertical definition of the plume as conditions permitted CPT-1 The water sample obtained at 38' bgs contained 0 66 ug/l MTBE The water ' sample obtained at 77' bgs contained 65 ug/l MTBE • CPT-2 The water sample obtained at 40' bgs did not contain contaminant concentrations above the laboratory reporting limits The water sample obtained at ' 70' bgs contained 120 ug/l TPH-G • CPT-3 The water sample obtained at 73' bgs contained 120 ug/l TPH-G, 6 6 ug/l benzene, 0 57 ug/l toluene, 2 8 ug/l ethyl benzene and 19 ug/I xylene ' It is noted that the laboratory reported that the TPH-G detected in CPT-2 and CPT-3 was not P ' consistent with the gasoline chromatogram None of the groundwater samples contained ETBE, DIPE, TBA or TAME above the laboratory reporting limits ' The lateral distribution of TPH-G in the shallow aquifer is presented in Figure 8 The adjacent Shell Station data points from the January 17, 2006 sampling event were obtained from the Geotracker database