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CLEARWATER <br /> G R O U P, I N C <br /> Evv-vomental Se,vrces <br /> 3.0 RESULTS <br /> 3.1 Subsurface Lithology <br /> Subsurface lithologies encountered during drilling consisted of well graded sand, silty and <br /> clayey sand and silty clay Correlation of beds between the installed wells was inconsistent <br /> Mostly silty clay was encountered in both SB-1 and SB-3 with some clayey sand A well <br /> graded sand was observed from approximately 21 feet bgs to near the terminus of each boring <br /> in SB-2, -4, and -6 SB-5 exhibited alternating beds of sands and clays The water table was <br /> encountered at approximately 16 feet bgs Depth to groundwater, measured in the installed <br /> monitoring wells, indicate a rise of approximately four feet in static water elevation , which is <br /> consistent with confined conditions Detailed soil sample descriptions are presented in <br /> Appendix B <br /> 3.2 Soil Sample Analytical Results <br /> . A total of 18 soil samples collected from borings SB-1 through SB-6 were analyzed <br /> Concentrations of TPHg were detected in borings SB-1, -2, -5, and -6 The highest <br /> concentration of TPHg (570 mg/kg) was detected below the groundwater table in SB-2 at a <br /> depth of approximately 25 feet bgs Low concentrations of TPHd were detected in borings <br /> SB-5 and SB-6 The highest concentration of TPHd (11 mg/kg) was detected below the <br /> groundwater table in SB-5 at a depth of approximately 25 feet bgs Low concentrations of <br /> benzene were detected in borings SB-1, -2 , and SB-5 The highest concentration of benzene <br /> (4 mg/kg) was detected below the groundwater table in SB-2 at a depth of approximately 25 <br /> feet bgs No analytes were detected in any of the soil samples from SB-3 and SB-4 <br /> Three soil samples were analyzed for TPHo, total lead, and volatile organics TPHo <br /> concentrations were not detected above method reporting limits in any of the soil samples <br /> Low concentrations of lead were detected in boring SB-1 at approximately 10 feet bgs (5 <br /> mg/kg) and 25 feet bgs (5 mg/kg) These concentrations are less than 10 times the soluble <br /> threshold limit concentration (STLC) for lead and is, therefore, not considered hazardous <br /> Low concentrations of naphthalene were detected in SB-1 (17 mg/kg) and SB-5 (26 mg/kg) <br /> Other volatile organics were detected including 1, 2, 4-trimethybenzene (4 8, 55, and 93 <br /> mg/kg), n-propylbenzene (9 mg/kg) and n-butylbenzene (0 5 mg/kg), all of which are <br /> associated with petroleum products <br /> 4 <br />