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(VATC A S S O C I A T E S I N C and a sample was collected from each well using a disposable bailer Groundwater well purge and sample logs are contained in Attachment I The groundwater samples collected from the wells were submitted to State certified Argon Laboratories (FLAP Cert No 2359) for chemical analysis of TPHg, total petroleum hydrocarbons as diesel (TPHd), and total petroleum hydrocarbons as kerosene (TPHk) utilizing EPA method 8015 modified, BTEX utilizing EPA method 8020, and oxygenate fuel additives including methyl tert butyl ether(MTBE) utilizing EPA method 8260 ANALYTICAL RESULTS The groundwater samples collected from wells MWI and MW2 contained detectable concentrations of TPHg at 110 micrograms per liter, gg/L and 190 pg/L, respectively Ethylbenzene was detected at 0 9 ug/L in the water sample collected from well MW2 MTBE was detected in wells MWI and MW2, at concentrations of 5 4 gg/L and 21 gg/L, respectively T-butanol was detected in well MW2 at a concentration of 28 ug/L No other fuel additives were detected above laboratory method reporting limits including di-isopropyl ether, ethyl t-butyl ether, t-amyl methyl ether, 1,2-dichloroethane, and 1,2-dibromoethane Groundwater matrix samples from wells MW3, MW4, MW5, MW6, and MW7 did not contain concentrations of TPHg, TPHd, TPHk, BTEX compounds, or fuel oxygenates above the laboratory reporting limits Analytical results for groundwater matrix samples are contained in Table 2 Laboratory data sheets and chain-of-custody documentation are contained in Attachment 2 CONCLUSIONS Concentrations of petroleum hydrocarbons in wells MWI and MW2 were within the historical range as established by previous sampling events but have generally decreased over time Concentrations of petroleum hydrocarbons remained below laboratory reporting limit at wells MW3, MW4, MW5, MW6, and MW7 TPHd and TPHk have not been detected in any of the wells for the last four quarters in wells MWI through MW4 and since wells MW5 through MW7 were installed The lateral extent of the petroleum hydrocarbon plume in groundwater appears to be receding RECOMMENDATIONS Based on the results of the first quarter 2003 monitoring event and the general trend of decreasing concentrations of petroleum hydrocarbons in wells MWI and MW2 since December 1999, we recommend one more quarter of sampling and if the trend remains the same we will recommend that the site be granted "No Further Action" (NFA) status w lwordpro16257711QR-2003 doc 3