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C A M B R I A i groundwater monitoring wells Boring and well specifications are described in Table 1 and locations are shown on Figure 2 Boring Depths The HSA well borings were drilled to 72 fbg and the CPT boring was advanced to 90 06 fbg Groundwater Depths• During drilling activities, a pore pressure dissipation test in CPT-1 indicated groundwater at 71 fbg, and groundwater was observed at approximately 69 fbg in well borings MW-2 through MW4 Blaine Tech Services, Inc (Blaine) of San Jose, California measured groundwater in wells MW-1 through MW-4 at depths ranging from 6180 to 65 26 fbg on November 16, 2001 Blaine's well gauging data is included in Appendix D Soil Types Soil types encountered during HSA drilling consisted predominantly of clayey silt (ML), sandy silt (ML), sand (SP), and silty sand (SM) at varying depths and thicknesses to the total • explored depth of 72 fbg Soil types from the HSA borings are recorded on the boring logs (Appendix C) Soil types encountered during the CPT boring include clay, silty clay, silt, clayey silt, cemented sand, and gravelly sand Another soil type encountered was "stiff fine-grained" which is a CPT category that does not translate directly into the Unified Soil Classification System In general, soils beneath the site are primarily fine-grained (silts and clays) with some coarse-grained zones (sands and silty sands) occurring at a depth of approximately 17 fbg Gregg's CPT log is presented in Appendix B Soil Chemical Analyses Selected soil samples from the borings were analyzed for TPHg, BTEX, and MTBE by EPA Method 8260B Groundwater Chemical Analyses Groundwater samples collected from boring CPT-1 and wells MW-I through MW-4 were analyzed for TPHg, BTEX, fuel oxygenates (MTBE, TBA, ETBE, DIPE, and TAME), 1,2-dibromoethane (EDB), and 1,2-dichloroethane (1,2-DCA) by 1359 4