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�C-- L D t ASS O C I ATE S I N C . reduce volatilization. Sample containers were then labeled with sample identification, placed on ice, and shipped under chain-of-custody to Sequoia Analytical. ' The groundwater samples from wells MWI, MW2, and MW3 were analyzed by Sequoia for TPHg, TPHd, TPHss, BTEX, and oxygenate fuel additives. Groundwater analytical results are summarized in Table 3, and laboratory data sheets are presented in Appendix F. 4.0 SUBSURFACE CONDITIONS ' Soils ingr oundwater monitoring wells MWI and MW2 from the surface to approximately 6.5 to 10 feet bgs consist of clayey sand. Soils from between 6.5 to 10 feet bgs and 11.5 to 15 feet bgs ' consist of lean clay. Soils from between 11.5 to 15 feet bgs and 21.5 to 25 feet bgs consist of elastic silt and varying amounts of poorly graded sand. Soils from between 21.5 to 25 feet bgs and 31.5 to 35 feet bgs consist of silt with sand and lean clay with sand. Soils from between 31.5 ' to 35 feet bgs and 36.5 to 40 feet bgs consist of elastic silt. Soils from 36.5 to 40 feet bgs and 43 feet bgs, the maximum depth explored in groundwater wells MMI and MW2, primarily consisted of lean to fat clay. Groundwater was encountered at approximately 26.5 feet bgs during drilling ' activities. Soils in boring SB2 from the surface to 40 feet bgs were not identified by lithology because this boring was advanced in approximately the same location as soil boring SB 1 and the soil lithology from the surface to 40 feet bgs was identified in boring SBI. Soils in boring SB2 from between ' 40 feet bgs and 41.5 to 45 feet bgs consist of lean clay. Soils from between 41.5 to 45 feet bgs and 51 to 55 feet bgs consist of sandy elastic silt. Soils from between 51 to 55 feet bgs and 67 feet bgs consist of fat and lean clay. Soils from between 67 feet bgs to 69.5 feet bgs consist of ' silty sand, clayey sand, and poorly graded sand. From 69.5 to 70 feet bgs, the maximum depth explored lean clay with sand was encountered. ' 5.0 ANALYTICAL RESULTS 5.1 Soil Analytical Results -Drilling Activities tSoil samples collected from borings MWI, MW2, and SB2 contained no detectable concentrations of BTEX or TPHss. TPHg and TPHd were detected at very low concentrations in tthe sample from boring MWI collected at 25.5 feet bgs. No detectable concentrations of TPHg and TPHd were detected in the remaining soil samples collected from borings MWI, MW2, or SB2. Analytical results of soil samples are summarized in Table 1. Laboratory data sheets and ' chain-of-custody documentation is presented in Appendix D. ' S�2 Groundwater Analytical Results Groundwater samples collected from wells MWI and MM2 contained no detectable concentrations of TPHg, TPHd, TPHss, BTEX, or oxygenate, fuel additives. Groundwater samples from wells MWI and MW2 contained 1,2-DCA at concentrations of 1.2 ppb and 2.0 ppb, W:17295 \s„rui.doc 5 1