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A S S O C I A T E S I N C calculated to be 0.001 or approximately 6.7 ft/mile. A summary of groundwater monitoring data is presented in Table 1. SAMPLING ACTIVITIES On October 14, 2002, ATC personnel collected groundwater samples from monitoring wells MWI, MW2, and MW3. The locations of the monitoring wells are shown on Figure 2. Prior to collection of groundwater samples, the depth to water, pH, electrical conductivity, and temperature were measured in the monitoring wells and recorded. A minimum volume of three well casings was purged from each well prior to sampling. The wells were allowed to recover and samples were collected from each well using disposable bailers. The groundwater matrix samples collected from each well were submitted to State-certified Argon Laboratories (FLAP Cert. No. 2359) for chemical analysis of TPHg utilizing EPA method 8015 modified, and BTEX and oxygenate fuel additives including MTBE utilizing EPA method 8260. Groundwater well purge and sample logs are contained in Attachment 1. ANALYTICAL RESULTS The groundwater analytical results measured at monitoring wells MWI, MW2, and MW3 showed detectable concentrations of TPHg, BTEX, MTBE, TBA, and 1,2-DCA. The measured concentration of TPHg at MWI was 500 pg/L. Ethyl benzene was detected at 3.6 pg/L, and xylenes were detected at 3.2 µg/L. MTBE was detected at 4.8 pg/L and 1,2-DCA at 12 µg/L. The measured concentration of TPHg at MW2 was 1,900 pg/L. Benzene was detected at 5.9 µg/L, toluene was detected at 4.0 µg/L, ethyl benzene was detected at 19 µg/L, and xylenes were detected at 19 p.g/L. MTBE was detected at 83 µg/L, TBA at 41 pg/L, and 1,2-DCA at 41 pg/L. The measured concentration of TPHg at MW3 was 770 µg/L. Toluene was detected at 1.8 µg/L, ethyl benzene was detected at 5.3 pg/L, and xylenes were detected at 8.8 µg/L. MTBE was detected at 120 µg/L, TBA at 25 µg/L, and 1,2-DCA at 47 µg/L. The Maximum Contaminant Level (MCL) for benzene, 1 µg/L, was exceeded at monitoring well MW2 which had detected concentrations of 5.9 µg/L. The MCL for MTBE, 13 pg/L, was exceeded at MW2 and MW3, which had detected concentrations of 83 µg L and 120 ug/L, respectively. CONCLUSIONS Groundwater flow direction and gradient is consistent with previous sampling events. Water table elevations have decreased since the July 2002 monitoring event. Groundwater analytical results show a general decrease in concentrations, though most remained within historical parameters as set by previous groundwater analytical results. w:lwordpro1224931Reportsl4QR-02.doc 3