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s4 . 15 June 2004 AGE-NC Project No 96-0254 Page 2 of 4 dedicated,disposable bailers The water sample from each well was transferred into three chilled 40- ml volatile organic analysis(VOA)vials containing 0 5 ml 18%hydrochloric acid(HCl)as a sample preservative and into one 1-liter amber bottle without a sample preservative After collection, the samples were labeled and placed in a chilled container for transportation under chain-of-custody to a California Department of Health Services(DHS)-certified analytical laboratory The ground water samples were analyzed for • Total petroleum hydrocarbons quantified as gasoline and as diesel (TPH-g and TPH-d) in accordance with EPA Method 8015 Modified • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 8021 • Fuel additives, including, di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), MTBE,tertiary-amyl methyl ether(TAME),tertiary-butyl alcohol(TBA), 1,2-dibromoethane (EDB) and 1,2-dicholoroethane(1,2-DCA) in accordance with EPA Method 8260B . 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determmed for each quarter from field data collected onl l December 2003 and 03 March 2004 The contaminant impact to ground water was assessed from the laboratory analytical data obtained from each sampling event 3 1 GROUND WATER ELEVATION AND GRADIENT The depth to ground water at the time of the Fourth Quarter 2003 monitoring event ranged between 7 15 feet and 7 98 feet below the tops of the well casings(btoc) At the time of the First Quarter 2004 monitoring event, depth to ground water ranged between 6 83 feet and 7 72 feet btoc The elevation of ground water in each well was calculated by subtracting the depth to ground water from the surveyed well casing elevations(Table 1) Ground water elevations could not be calculated for wells MW-IA,MW-IB,MW-4 and MW-7,which are replacement wells installed in June 2003 that have not been surveyed yet Utilizing the depth to water measurements from wells MW-2A, MW-3, MW-5 and MW-6,the calculated ground water elevations at the site ranged between 28 99 feet above mean sea level (MSL) in well MW-2A and 30 05 feet above MSL in well MW-6 during the Fourth Quarter 2003,and ranged between 29 33 feet above MSL in MW-2A and 30 37 feet above MSL in MW-6 in the First Quarter 2004 i Advanced GeoEnvironmental Inc