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t18 January 2004 . AGE-NC Project No 95-0141 tPage 2 of 5 t Temperature,pH and conductivity of purged ground water were measured at regular purge intervals using an Oakton water analyzer The field data and field sheets are included in Appendix B Purged water was temporarily stored on-site in 5 5-gallon DOT-approved H-17 storage drums pending proper disposal' ' ' 2 12 Ground Water Sample Collection and Analysis Prior to the collection of ground water samples, the depth to ground water was re-measured in each ' well to ensure that a minimum of 80% of the initial water volume had recharged A water sample was'then collected from each well using a new, dedicated, disposable plastic bailer Immediately . upon retrieval, the sample was transferred into three properly labeled 40-m1 EPA-approved volatile ' organic analysis(VOA)vials containing 0 5 ml 18%hydrochloric acid as a sample preservative The samples were Iogged on a chain-of-custody form,stored in a chilled container and transported under cham-of custody to Cal Tech Environmental Laboratories (CTEL), a California Department of ' Health Services (DHS)-certified laboratory, The ground water samples were analyzed for • Total petroleum hydocarbons quantified as gasoline (TPH-g) in accordance with EPA • Method 8015 Modified, ' Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tentary-butyl ether (MTBE) in accordance with EPA Method 8021, and ' • Di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), MTBE, tertiary-amyl methyl ether(TAME),tertiary-butyl alcohol(TBA), 1,2-dibromoethane(EDB), 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B ' 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determined from field data collected and ' the contaminant impact to ground water was assessed from the laboratory analytical data collected on 24 September 2003 1 3 1 GROUND WATER ELEVATION AND GRADIENT ' At the time of the September 2003 monitoring event,depths to ground water ranged from'21 11 feet to 22 16 feet below the tops of the well casings (btoc) Ground water elevations at the site ranged from 13 76 feet below mean sea level (MSL) in well MW-l0A to 14 54 feet below MSL in well MW-11B (Table 1) The tops of the well, screens in MW-3 and MW-5 were drowned by approximately 7 to 8 feet ' Advanced GeoEnvironmental,[Fie