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i" psi <br /> Chemical Analytical Methods and Results <br /> Nine groundwater samples were analyzed using EPA Methods 5030/8015, 602 and 8260 for <br /> Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene <br /> (BTEX) and fuel oxygenates including Methyl-tert-butyl-ether (MTBE), Tert-Butyl Alcohol <br /> (TBA), Di-Isopropyl Ether (DIPS), Ethyl tent-butyl ether (ETBE), Tert-Amyl Methyl Ether <br /> TAME), 1,2-Dichloroethane (1,2-DCA) and Ethylene Dibromide (EDB) The analytical results <br /> of the groundwater samples for this sampling event are attached and listed below in Table <br /> 1(historic data is presented in attached spreadsheet Table 2), <br /> Table 1 Current Quarter Groundwater Chemical Data (July 30, 2001) <br /> .Sample TPHG Ben Tol Ethyl Xyl TND <br /> TBA DIPE ETBE TAME <br /> ug/1 u 11 u /l ug/1 U/1 ug/1 u9/1 U /1 u /l <br /> MW-1 ND ND ND ND ND ND ND ND ND <br /> MW-2 1900 16 46 43 18 ND ND ND ND ND <br /> MW-3 28000 230 280 1200 5400 ND ND ND ND ND <br /> MW-4 ND ND ND ND ND ND ND ND ND ND <br /> MW-5 ND ND ND ND ND ND ND ND ND ND <br /> MW-6 300 ND ND ND ND ND ND ND ND ND <br /> MW-7 ND ND ND ND ND ND ND ND ND ND <br /> MW-8 ND ND ND ND ND ND ND ND ND ND <br /> �• MW-9 46000 850 330 3100 12000 ND ND ND ND ND <br /> Blank ND ND ND ND ND ND ND ND ND ND <br /> ND - None detected ug/I - micrograms per liter Ben - Benzene Tot - Toluene Xyl - Xylene <br /> Fuel Ox - Fuel Oxygenates by Method 8260 from Dec, 1997 forward Ethyl - Ethylbenzene <br /> 1,2 Dichloroethane and Ethylene Dibromide ND in all wells, these analyses discontinued in 2000 <br /> Discussion <br /> Groundwater flow direction is northerly at a low flow gradient which is consistent with <br /> historically observed trends (see Figures 1, 2 and 3) Groundwater levels have declined <br /> slightly since the last quarter Contaminants were observed in the Wells MW-2, MW-3, MW- <br /> 6 <br /> W- <br /> 6 and MW-9, similar to the previous quarter Contaminants were not observed in Well MW-1 <br /> Contaminant concentrations decreased very slightly in Wells MW-3 and MW-9 These two <br /> monitoring wells have historically shown elevated concentrations on the site and observed <br /> fluctuations have been interpreted as local desorption from sediment near the casing Recent <br /> subsurface Investigations and sampling with flowing sand conditions near these wells may have <br /> caused local contaminant desorption, increasing observed concentrations for this quarter <br /> The contract sampler noted 0 14 feet of separate phase product (SPP) in MW-3 and 0 3 feet <br /> SPP In MW-9 These are the third observations of SPP on the site in five years, Wright has not <br /> located any on-site SPP sources which could account for this observation In our opinion, this <br /> SSP may have been released during the latest drilling phase where flowing conditions may have <br /> allowed release of absorbed product It should be noted that while this SPP was observed for the <br /> Page 2 <br />