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' Chemical Analytical Methods and Results Nine groundwater samples were analyzed using EPA Methods 503018015, 602 and 8260 for Total Petroleum �J Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTE X) and fuel oxygenatesinciuding Methyl-tert-buty1-ether (MTBE), Tert-Butyl Alcohol (TBA), Di-Isopropyl Ether (RIPE), 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 in attached spreadsheet Table 2). Table 1. Current Quarter Groundwater Chemical Data(April 8,2003) Sample TPHG Ben Tol Eth 1 X 1 MTBE TBA D1PE ETBE TAME u u u u um u I u u u u MW-1 ND ND ND ND ND ND ND ND ND ND MW-2 2200 4.0 ND M 42 IS ND ND ND ND ND W-3 19000* 130 1,90 740 2900 ND ND ND MW-4 ND ND ND ND ND ND ND ND ND ND ND ND MW-5 ND ND ND 1.6 4.4 ND ND ND MW-6 350 ND ND ND ND ND ND ND ND ND ND ND MW-7 ND ND 0.77 ND ND ND MW-8 NDND ND ND ND ND 3.6 l2 ND ND ND MW-9 47000# 500 100 2100 6100 ND ND Blank NDND ND ND ND ND NI) ND ND ND ND-None detected u ND - -micrograms per liter. Ben-Benzene To]-Toluene Xyl-Xylene Fuel Ox.-Fuel Oxygenates by Method 8260 from Dec., 1997 forward. Ethyl-Ethylbenzene 1,2 Dichloroethane and Ethylene Dibromide ND in all wells;these analyses discontinued in 2000. *-0.08 feet of degraded product present on water in well at time of sampling;sampler removed 80 milliliters. #-0.05 feet of degraded product present on water in well at time of sampling;sampler removed 30 milliliters. F Discussion 1 1 P Groundwater pow direction is northerly at a pow gradient that is consistent with historically observed trends (see Figure 11. Groundwater levels have declined slightly in wells since the last quarter. TPHG levels decreased in wells MW-3 and MW-9. Benzene concentrations declined in Well MW-3 and only increased slightly in MW-9. Floating product was present in MW-3 (apparent 0.08 feet) and in MW-9 (apparent 0.05 feet) and a total of about 120 milliliters was removed. MTBE and fuel oxygenates were not detected in any well a , i a Contaminant TPHG concentrations decreased in MW-3 and MW-9 compared to the first quarter. This decrease appears to follow a decline in groundwater levels suggesting a residual source in the wells vicinity. Wells MW-3 fl i and MW-9 have historically shown elevated concentrations on the site and observed fluctuations have been $ s interpreted as local contaminant desorption from sediment near the casing. Separate phase product was observed in MW-3 and MW-9 during 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 i volatile content which in our opinion indicates a dissolved plume of degraded fuel depleted in dissolved volatile constituents (see Figures 2, 3 and 4). The interpreted location of the plume continues to remain staric with no net movement. 1 Page 2 �'