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Mr Michael Infurna Page 2 Prior to sampling, monitoring wells MW 1 through MW3 were purged of a minimum of three well casing volumes During the purging process the physical parameters of temperature, pH and electrical conductivity were measured A slight sheen was noted during the purging of well MW3 Samples were collected after the physical parameters had stabilized and water levels had recovered at least 97% Purge water was contained in appropriately labeled DOT-approved 55-gallon drums The drums are currently being stored onsite Purge logs are included in Attachment A Groundwater samples were delivered under chain of custody protocol to Argon Laboratories (FLAP #2359) Analysis consisted of BTEX using EPA method 8020, TPHg and TPHd using modified EPA method 8015, and gasoline oxygenate additives, 1,2 DCA and EDB using EPA method 8260 GROUNDWATER ANALYTICAL RESULTS EDB and 1,2 DCA were not detected in any site wells No detectable concentrations of TPHg, TPHd, BTEX, or gasoline oxygenate additives were present in the samples collected from wells MW1 and MW2 In well MW3, benzene and total xylenes were detected just above the detection limits at concentrations of 0 9 parts per billion (ppb) and 0 8 ppb, respectively The remaining BTEX constituents, toluene and ethylbenzene, were at non-detectable levels TPHg was detected at a concentration of 1,300 ppb MTBE and TPHd were reported at concentrations of 1,200 ppb and 2,100 ppb, respectively Analytical results are summarized in Table 2 Attachment B contains laboratory reports and chain of custody documentation SUMMARY • Groundwater levels at the site fell since the last round of sampling • After reversing to a southeasterly direction last quarter groundwater flow direction continues to be towards the southeast • TPHg, TPHd, BTEX, gasoline oxygenates, 1,2 DCA and EDB have been at non-detectable levels in wells MWI and MW2 since sampling began at the site • In well MW3, concentrations of TPHd, TPHg, and MTBE continue to decrease compared to previous sampling events Benzene and xylenes were detected in well MW3 for the first time since November, 2000 CONCLUSIONS No target analytes have been detected in either well NMI or MW2 since sampling began Contaminant concentrations at the site appear to have a relationship to groundwater level fluctuation but demonstrate the characteristics of a stable plume w0013ey chtlgmr13gm2001 doc