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a A S S O C I A T E S I N C After the CPT borings were advanced, Geoprobe soil borings CPT 1 a and CPT2a were advanced immediately adjacent to each CPT boring Soil boring CPTla was advanced to approximately ' 109 feet bgs and CPT2a was advanced to approximately 114 feet Groundwater samples were taken from both boreholes using a Hydropunch groundwater sample was collected from each boring into the appropriate sample containers, labeled and stored in a cooler with ice The CPT borings and the Geoprobe borings were then grouted to the surface with cement slurry 2_2 Soil Matrix Sample Analysis ' Selected soil samples collected from the hollow stem auger bonngs were kept for laboratory analysis Sample tubes were capped at each end using Teflon tape and plastic end caps, and ' labeled, and stored in a cooler with ice Selected soil samples from the borings were delivered under chain-of-custody protocol to State-certified Excelchem located in Roseville, CA (FLAP Cert No 2119) for chemical analysis ' Soil matrix samples from borings MW4 through MW8 collected at depths of approximately 40 feet bgs and 50 feet bgs were analyzed for hexvalent chromium by EPA Method 7196 and subsequently by EPA Method 7199 Additionally soil samples were analyzed for total organic carbon by EPA Method 9060, total alkalinity by EPA Method 232013, and pH by EPA Method 9045C These analytes were selected to provide additional information in anticipation of potential future remediation Copies of the analytical reports and chain of custody documentation are included in Appendix D 2_3 Well Development L Groundwater monitoring wells MW4 through MW8 were developed on September 25 and 26, 2002 and October 1, 2002 The wells were purged using surge and bail techniques 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 ' All on-site wells were surveyed on October 22, 2002 by ATC and tied into the elevations of the existing wells Survey data is included in Table 2 224 Fourth Ouarter Groundwater Sampling and Analysis Fluid levels were taken on October 1, 2002, utilizing an electronic water probe capable of ' measuring with an accuracy of I/100 of a foot Monitoring data is presented in Table 2 Fourth quarter groundwater sampling was conducted on September 25 and 26 and October 1, ' 2002 One groundwater sample each was collected from wells MW1 through MW8 and the facility well The samples were collected after purging a minimum of three well volumes and stabilization of electric conductivity, pH, and temperature Field purge logs are presented in ' Appendix C Subsequent to purging, groundwater was sampled and transferred to appropriate sample containers, using a clean, disposable bailer with a bottom emptying device to reduce ' w lwordpro1625831reports\Welt_install_rpt doc 4