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14� <br /> Groundwater Contour Map and Flow Gradient <br /> A groundwater contour map to a known datum was prepared for the data listed in Table 1 above <br /> (see Figure 1) The groundwater flow direction was to the northerly under a calculated gradient <br /> of 0 0027 The flow direction is consistent with historic observed trends, and remains <br /> relatively flat Overall groundwater levels appear to have risen about 0 5 foot from the <br /> previous quarter <br /> Chemical Analytical Methods and Results <br /> Nine groundwater samples were analyzed using EPA Methods 503018015, 602 and 8260 f o r <br /> Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene <br /> (BTEX) and fuel oxygenates including Methyl-tent-butyl-ether (MTBE), Tert-Butyl Alcohol <br /> (TBA), Di-Isopropyl Ether (DIPE), Ethyl tert-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 (January 17, 2001) <br /> iSample TPHG Ben Tot Ethyl Xyl MTBE TBA DIPE ELBE TAME <br /> u /l u /I u /l ug/1 u /l u /I ug/1 u /l u /l u /l <br /> MW-1 ND NO NO NO NO NO NO ND NO NO <br /> MW-2 1400 62 58 54 66 NO NO ND NO NO <br /> MW-3 11000 100 93 390 1900 NO NO NO NO NO <br /> MW-4 NO NO NO NO NO NO NO ND NO NO <br /> MW-5 ND NO NO NO NO NO NO ND NO NO <br /> MW-6 600 NO NO NO NO NO NO NO NO NO <br /> MW-7 NO NO NO NO NO NO NO NO ND NO <br /> MW-8 NO ND NO NO NO NO NO ND NO NO <br /> MW-9 19000 550 150 1400 4700 NO NO ND NO NO <br /> Blank NO NO NO NO NO NO NO ND I NO NO <br /> NO - 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 NO in all wells <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 risen about <br /> • 0 5 feet since the last quarter This water rise is attributed to natural aquifer recharge <br /> Page 2 <br />