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a Chemical Analytical Methods and Results Eight groundwater samples were analyzed using EPA Methods 503018015, 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) The analytical results of the groundwater samples for this sampling event are attached and listed below in Table 1 (and Figures 2, 3 and 4) and historic data is presented to attached spreadsheet Table 2) - _ Table 1 Current Quarter Groundwater Chemical Data(December 23,2002) Sample TPHG Ben TO] Ethvl a] MTBE TBA D1PE ETBE TAME UO ugA u I u I u u l ugfl u UO u MW-I ND ND ND ND ND ND ND ND ND ND MW-2 1400 ND ND 23 88 ND ND ND ND ND MW-3 290000* 280 740 3200 16000 ND ND ND ND ND MW-4 ND ND ND ND ND ND ND ND ND ND MW-5 ND ND ND 16 44 ND ND ND ND ND MW-6 No data No data No data No data No data No data I No data I No data No data No data MW-7 ND ND 077 ND ND ND ND ND ND ND MW-8 ND ND ND 36 12 ND ND ND ND ND MW-9 190000# 940 310 $100 17000 ND ND ND ND ND Blank ND ND ND ND ND ND ND ND ND ND ND-None detected LIM-micrograms per liter Ben-Benzene Tot-Toluene X%I-Xvlene Fuel Ox -Fuel Oxvaenates by Method 82.60 from Dec 1997 forward Ethvl-Ethvibenzene 1 2 Dtchloroethane and Ethklene Di bromide ND in all wells these analvses discontinued to 2000 * 0 12 inches o1 degraded product present on water inwell at time of sampling #-0 03 inches of degraded product present on water in well at time of sampling No data—Not sampled due to car parked over well on Dec 23,2002 Discussion Groundwater flow direction is northerly at a flow gradient that is consistent with historically observed trends (see Figure 1) Groundwater levels have declined slightly In wells since the last quarter TPHG levels increased in wells MW-3 and MW-9, and declined in Well MW-2 Benzene concentrations declined in Well MW-3 and only increased slightly in MW-9 Floating product was present in MW-3 (apparent 0 12 feet) and in MW-9 (apparent 0 03 feet) MTBE and fuel oxygenates were not detected in any well Contaminant TPHG concentrations increased in MW-3 and MW-9 and declined slightly in MW-2 Wells MW-3 and MW-9 have historically shown elevated concentrations on the site and observed fluctuations have been interpreted as local contaminant desorption from sediment near the casing Separate phase product was observea in MW-3 and MW-9 dunng this sampling and the increase In TPHG is attributed to the presence of this degraded product in the wells and sample collection However the presence of product did not cause a large rise in BTEX volatile content (and Benzene decreased in Well MW-3) which in our opinion indicates a dissolved plume of degraded fuel depleted in dissolved volatile constituents (see Figures 2, 3 and 4) I Page 2