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' 12 January 2005 iAGE-NC Project No 97-0326 ' Page 3of11 ' bentonite pellets) was placed between each filter pack interval to minimize the potential for cross contamination into the screened section of the well Each bentonite seal was formed by pouring coated bentonite pellets through the hollow stem augers,into the annulus and allowing them to settle ' (hydrate) on the filter pack The remaining annular space above the uppermost screen interval and bentonite seal was filled to approximately 1-foot bsg with portland cement grout Water-tight,traffic- rated well boxes were then installed over the wells utilizing a neat cement As-built well diagrams ' are depicted on the boring logs in Appendix B 2 14 Laboratory Analyses of Soil Samples Selected soil samples were analyzed for ' Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 8015M, ' Benzene,toluene,ethylbenzene and total xylenes(BTEX)and the fuel additives di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), methyl tertiary-butyl ether (MTBE), tertiary-amyl methyl ether(TAME), tertiary butanol (TBA), 1,2-dichloroethane(1,2-DCA) ' • and 1,2-dibromoethane (EDB) in accordance with EPA Method 8260B 2 1 5 Monitoring Well Development On 05 April 2004,monitoring wells MW-7 through MW-9 were developed utilizing an inertiapump Ground water was purged from each monitoring well until ground water was visually sediment free Approximately 20 gallons of water were removed from single-level well MW-7, and between ' 1 25 and 12 5 gallons were removed from multi-level wells MW-8 and MW-9 Ground water temperature,pH and conductivity were measured at regular intervals during purging using an Oakton water analyzer Field sheets and data are included in Appendix C Purged water was stored on-site in properly labeled, 55-gallon DOT-approved drums ' 2 1 6 Well Head Survey ' On 06 April 2004, a California state-licensed survey engineer from Baumbach & Piazza, Inc surveyed the elevation at the top of the well casing of monitoring wells MW-7 through MW-9 to the nearest 0 01-foot relative to City of Stockton Bench Mark#29, surveyed at 12 06 feet above mean sea level (MSL) The results of the monitoring well survey are contained in Table 1 The surveying report (Baumbach & Piazza, Inc ) is presented in Appendix D ' Advanced GeoEnvironmental,Inc