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n 3i Chemical Analytical Methods and Results Nine groundwater samples were analyzed using EPA Methods 5030/8015 602 and 8260 for Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and fuel oxygenates including Methyl-tert-butyl-ether (MTBE), Tert-Butyl Alcohol (TBA), DI-Isopropyl Ether (DIPE), Ethyl tert-butyl ether (ETBE), Tert-Amyl Methyl Ether TAME), 1,2-Dichloroethane (1,2-DCA) and Ethylene Dibromide (EDB) The analytical results of the groundwater samples for this sampling event are attached and listed below in Table 1 (historic data is presented in attached spreadsheet Table 2), Table 1 Current Quarter Groundwater Chemical Data (Nov. 16, 2001) Sample TPFK3 Ben Tof Eth I Xyl MTBE TBA DIPE ETRE TAME u /l u /l u /l ug/l] u /I u /l u /l U'9/1 ug/1 u /l MW-1 ND NO NO NO ND NO NO ND ND ND MW-2 8600 84 1 9 17 14 NO NO NO NO NO MW-3 67000 1110 1600 3600 19000 NO NO ND NO ND MW-4 ND NO NO ND NO NO NO NO ND NO MW-5 ND NO ND NO ND NO NO NO NO NO MW-6 660 ND NO NO NO NO NO ND NO NO MW-7 NO NO ND NO ND ND NO NO ND NO MW-8 NO NO NO NO NO NO NO ND NO ND MW-9 54000 1300 480 4100 15000 ND NO ND ND ND Blank NO NO NO NO Na NO NO NO NO ND NO - None detected ug/l - micrograms per liter Ben - Benzene Tol - Toluene Xyl - Xylene Fuel Ox - Fuel Oxygenates by Method 8260 from Dec, 1997 forward Ethyl - Ethylbenzene 1,2 Dtchloroethane and Ethylene Dibromide NO in ail wells, these analyses discontinued in 2000 Discussion Groundwater flow direction is northerly at a low flow gradient which is consistent with historically observed trends (see f=igures 1, 2 and 3) Groundwater levels have declined slightly since the last quarter Contaminants were observed in the Wells MW-2, MW-3, MW- 6 and MW-9, similar to the previous quarter Contaminant concentrations increased slightly in Wells MW-3 and MW-9 These two monitoring wells have historically shown elevated concentrations on the site and observed fluctuations have been interpreted as local desorption from sediment near the casing Recent subsurface investigations and sampling with flowing sand conditions near these wells may have caused local contaminant desorption, Increasing observed concentrations for this quarter The contract sampler noted 0 092 feet of separate phase product (SPP) in MW-3 and 0 065 feet SPP in MW-9 The sampler bailed a total of 265 milliliters of SPP from the wells These are the fourth observations of SPP on the site In five years, Wright has not located any on-site SPP sources which could account for this observation In our opinion, the dissolved plume • remains centered at MW-3 and MW-9, and has historically remained in this area, no net dissolved plume movement is noted which is consistent with historic observations Page 2