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v 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 (ETRE), 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(August 2,2002) Sample TPHG Ben TO[ Ethyl Xyl MTBE TBA DtPE ETBE TAME ugn u u UFA u tio ugfl UE2 u ug/1- MW-1 ND ND ND ND ND ND ND ND ND ND MW-2 3400 ND ND 1 82 54 ND ND ND ND ND MW-3 50000 570 990 2300 11000 ND ND ND ND ND MW4 ND ND ND ND ND ND ND ND ND ND MW-5 ND ND ND ND ND ND ND ND ND ND MW-6 670 ND 24 ND ND ND ND ND ND ND MW-7 ND ND 077 ND ND ND ND ND ND ND MW-8 ND ND ND ND ND ND ND ND ND ND MW-9 71000 1200 360 470-0 16000 ND ND ND ND ND Blank ND ND ND ND ND ND ND ND ND ND . ND-None detected ugll-micrograms per liter Ben-Benzene Tol-Toluene Xyl-Xylene Fuel Ox -Fuel Oxygenates by Method 8260 from Dec, 1997 forward Ethyl-Ethylbenzene 1,2 Dichloroethane and Ethylene Dibromide ND in ail wells,these analyses discontinued in 2000 Discussion Groundwater flow direction is northerly at a flow gradient that is consistent with historically observed trends (see Figures 1, 2 and 3) Groundwater levels have risen slightly in wells MW-3, MW-7 and MW-8 since the last quarter This rise appears to be caused by a small groundwater mound near MW-7 apparently caused by canal flow Contaminants were observed in the Wells MW-2, MW-3, MW-6 and MW-9, similar to the previous quarter Floating Product was present in MW-3 (apparent 0 30 feet) and in MW-9 (apparent 0 25 feet) Approximately one liter was bailed off each well prior to groundwater sampling Contaminant concentrations increased slightly in MW-9 and declined slightly in MW-3 These two monitoring wells 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 observed in MW-3 and MW-9 during this sampling However, the presence of product did not significantly cause a large rise in volatile content (when compared to historic data), which in our opinion, indicates a degraded fiiel product depleted in dissolved volatile constituents Conclusions and Recommendations Groundwater flow direction was northerly under a low calculated gradient In our opinion,the mapped contaminant dissolved plume continues to occur near the center of the site, sunilar to historic observations Page 2