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A S 4Y_Z S O C I A T E S I N C 226 Groundwater„Sampling and Analysis ' On December 14 and 15, 2000, groundwater samples were collected from wells MW1 through MW8 and the on-site domestic well (DW) The samples were collected after purging a minimum of three well volumes and stabilization of electric conductivity, pH, and temperature Purge logs are presented in Appendix D Subsequent to purging, groundwater was sampled and transferred to appropriate sample containers, using clean, disposable bailers with bottom emptying devices to reduce volatilization Sample containers were then labeled with sample identification, placed on ice, and shipped under chain-of-custody to Argon Laboratories ' The groundwater samples from wells MW1 through MW8 and DW were analyzed by Argon Laboratories for TPHg by EPA Method 8015, BTEX by EPA Method 8020, and MTBE, TAME, ETBE, TBA, and DIPE by EPA Method 8260 Groundwater analytical results are summarized in Table 2, and laboratory data sheets are presented in Appendix E 3.0 SUBSURFACE CONDITIONS 3A Geology to Gregg Drilling & Testing Inc logged soil in the CPT soil boring at intervals of less than one foot and soil types varied substantially Soil from the surface to first encountered groundwater, approximately 35 feet bgs, generally of consisted of varying types of silts with layers of silty sands and clay Soil from approximately 35 feet to 65 feet bgs consisted of stiff fine grained material with interbedded layers of silt Soil generally consisted of varying types of silts with layers of sand and silty sands from depths between 65 feet bgs and 85 feet bgs Soil generally consisted of varying types of sands with silty sand from depths between 85 feet bgs and 117 feet bgs Soil generally consisted of varying types of silt from depths between 117 feet bgs and 140 Stiff fine grained material was encountered from 140 to 144 feet bgs, the maximum depth explored The Gregg Drilling & Testing Inc boring log and supporting documentation are contained in Appendix A Soil in borings MW4, MW5, MW6, and MW7 generally consisted of silt, elastic silt, and sandy silt from the surface to depths between 36 to 40 feet bgs, although layers of poorly graded sand and silty sand were found in borings MW4 and MW7 and poorly graded sand was encountered in boring MW6 at approximately 28 feet bgs Soil generally consisted of silty sand from depths between 36 to 40 feet bgs and 41 5 to 45 feet bgs Soil in borings MW4 and MW5 generally consisted of poorly graded sand and silty sand from depths between 41 5 to 45 feet bgs and 81 to 815 feet bgs, although layers of lean clay and sandy silt were found in boring MW5 Soil in boring MW6 consisted of silt and elastic silt from depths between 41 5 to 45 feet bgs and 56 5 to ' 60 feet bgs Soil in boring MW6 consisted of lean clay from depths between 56 5 to 60 feet bgs and 71 5 to 75 feet bgs Soil in boring MW6 consisted of silt from depths between 71 5 to 75 1 10 feet bgs and 80 5 feet bgs The lithology in boring MW7 was similar to MW6 except the clay w 1163931reportslsumn doc 4