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C A M B R I A <br /> Soil Types Soil types encountered while drilling the borings consisted <br /> primarily of alternating beds of clay (CL), silty clay (CL), clayey <br /> silt (ML), stiff-fine grained,' and silty sand/sand (SM) mixtures <br /> Generally continuous beds of interbedded sand(SP) and gravelly <br /> sand (SP) occurred at approximate depth intervals of 40 to 45 <br /> fbg (except in CPT-7) and 68 to 75 fbg A deep sandy layer was <br /> also observed in borings CPT-3 (98 to 100 fbg), CPT4 (85 to <br /> 89 fbg), CPT-5 (92 to 96 fbg), and CPT-7 (93 to 97 fbg), <br /> although the depths vaned Sediments encountered between the <br /> coarse-grained zones vaned from boring to boring without a <br /> consistent stratigraphic order but consisted dominantly of beds <br /> of silt (ML) and clay (CL) Electronic boring logs are included <br /> in Gregg's CPT report included as Appendix C <br /> Chemical Analyses: Soil and groundwater samples were analyzed for TPHd by EPA <br /> Method 8015 (Modified), and groundwater samples were <br /> additionally analyzed for TPHg, BTEX, and 1,2-DCA by EPA <br /> • Method 8260B <br /> HYDROCARBON DISTRIBUTION IN SOIL <br /> TPHd was detected in soil samples collected from.borings CPT-3, CPT-4, and CPT-7 at five fbg <br /> at concentrations of 12, 11 and 3 9 ppm,respectively However, the hydrocarbon pattern did not <br /> match the diesel standard and was unidentifiable TPHd was not detected in the soil samples <br /> collected from borings CPT-5 or CPT-6 <br /> I <br /> I <br /> Soil chemical analytical data are summarized in Table 2 and presented on Figure 2 Laboratory <br /> analytical data are presented in Appendix D <br /> HYDROCARBON DISTRIBUTION IN GROUNDWATER <br /> TPHd was detected in groundwater samples from all the borings at concentrations ranging from <br /> 53 to 680 ppb The laboratory noted that none of the hydrocarbons reported as TPHd matched <br /> the laboratory's diesel standard Upon further review, the laboratory determined that the <br /> hydrocarbons were aged gasoline TPHg was also detected in groundwater samples from all the <br /> borings at concentrations ranging from 79 to 2,000 ppb The laboratory noted that some of the <br /> ' A CPT electronic log classification that does not translate to the unified soil classification system <br /> 0943 5 <br />