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/l 6� Chemical Analytical Methods and Results Nine groundwater samples were analyzed using EPA Methods 5030/8015, 602 and 8260 f or 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 (April 24, 2001) Sample TPI-IG Ben Tol Eth i X I MTBE TBA RIPE ETEE TAME u /I u /l u /I u /l u /l u /I u /I u /l u /i u /l MW-1 NO NO NO NO NO NO NO NO NO NO MW-2 1800 1 8 1 3 60 29 NO NO NO NO NO MW-3 66000 1200 1400 3800 19000 NO NO NO NO NO MW-4 NO NO NO ND ND NO NO NO NO NO MW-5 NO NO NO NO NO NO NO NO NO NO MW-6 950 NO NO NO NO NO NO NO NO NO MW-7 ND NO NO NO ND NO NO NO ND NO MW-8 NO NO NO NO NO NO NO NO NO NO MW-9 78000 1200 540 4100 16000 NO NO NO NO NO Blank NO ND NO ND NO NO NO NO NO NO NO - None detected ug/l - micrograms per liter Ben - Benzene To] - Toluene Xyl - Xyfene Fuel Ox - Fuel Oxygenates by Method 8260 from Dec, 1997 forward Ethyl - Ethylbenzene 1,2 Dichloroethane and Ethylene Dibromide NO in all wells, these analyses stopped in 2000 Discussion Groundwater flow direction is northerly at a low flow gradient which is consistent with historically observed trends (see Figures 1, 2 and 3) Groundwater levels have risen about 0 3 feet since the last quarter Contaminants were observed in the Wells MW-2, MW-3, M W- 6 and MW-9, similar to the previous quarter Contaminants were not observed in Well M W- 1, which previously had very low levels of TPHG Contaminant concentrations increased 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 04 feet of separate phase product (SPP) in MW-3 and 0 03 feet SPP in MW-9 The contract sampler noted stains in the Well MW-9 casing with blebs of free product in well water in the previous quarter These are the second observations of SPP on the Page 2