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t,,(Vv:ATC A S S O C I A T E S I N C PL 2_4 Monitorinp,Well Develonrnent Groundwater monitoring wells MW5 through MW7 were developed on December 12, 2001 Each well was purged until the extracted water was relatively sediment free Development logs are included in Appendix C Purgewater was temporarily stored on site in 55-gallon drums ' 2.5G roundwater Sam lin and Ana! sis ' Fluid levels were taken on December 12, 2001, utilizing an electronic water probe capable of measuring with an accuracy of 11100 of a foot, and groundwater samples were collected from ' monitoring wells MW 1 through MW7 In addition, a CPT boring was advanced on December 13, 2001, and a groundwater sample collected from the resulting boring CPT1 Groundwater samples were placed on ice and delivered under chain-of-custody documentation to ' Argon for chemical analysis Groundwater samples were analyzed by Argon for TPHg, TPHd, and TPHk by EPA method 8015 modified, BTEX by EPA method 8020, and MTBE, TAME, ETBE, DIPE, and TBA by EPA method 8260 In addition, the CPT 1 groundwater sample was analyzed for TPHmo by EPA method 8015 modified The analytical results for groundwater samples are summarized in Table 2 Laboratory data sheets and chain-of-custody documentation are included in Appendix D All on-site wells were surveyed on March 18, 2002 by State-licensed land surveyor, Condor Ear#h Technologies (#7698) The wells were surveyed to NAD83 horizontal datum and NAVD88 vertical datum The equipment used to survey the wells to the horizontal datum was a Leica GPS 500 centimeter-level GPS system in RTK mode The equipment used to survey the wells to the vertical datum was a Topcon Auto-Level optical level Survey data are presented in Table 4 3.4 SUBSURFACE CONDITIONS 3.1 Geology Soil from the hollow stem auger borings VEW I through VEW3 generally consisted of inorganic clays from the surface to approximately 6 5 to 10 feet bgs Soil consisted of silty sand and poorly graded sand from depths between 6 6 to 10 feet bgs and 315 to 35 feet bgs Soil consisted of 1 inorganic clay and silt, and silty clay from depths between 31 5 to 35 feet bgs and 46 5 feet bgs, - - the maximum depth explored in borings VEW 1 through VEW3 Soil from the hollow stem auger boring MW5 generally consisted of a gravel-sand-silt mixture from the surface to depths between 6 5 feet to 10 feet bgs Soil generally consisted of silty fine sands from depths between 6 5 feet to 10 feet bgs and 11 5 feet to 15 feet bgs Soil generally consisted of poorly graded fine sands from depths between 11 5 feet to 15 feet bgs and 21 5 to 25 feet bgs Soil generally consisted of inorganic silts from depths between 21 5 feet to 25 feet bgs w 162117\,,pM -yrs aoc 4