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t ' Mr Michaellnfurna Page 2 • Samples were collected after the physical parameters had stabilized and water levels had recovered to at least 99% of pre-purge levels Purge water was contained in appropriately labeled DOT-approved 55-gallon drams 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) for the analysis of BTEX using EPA method 8020, TPHg and TPHd using modified EPA method 8015, and gasoline oxygenate additives using EPA method 8260 Groundwater Analytical Results 1,2-DCA and EDB continue to be at non-detectable levels in wells MWl through MW3, and no detectable concentrations of TPHg, TPHd, BTEX, or gasoline oxygenate additives were present in wells MW 1 and MW2 In well MW3, benzene and toluene were not detected No gasoline oxygenate additives were detected except for MTBE, which was detected at a concentration of 1,400 parts per billion (ppb) TPHg was detected at a concentration of 1,300 ppb, and TPHd was detected at a concentration of 2,500 ppb Analytical results are summarized in Table 2 Attachment B contains laboratory reports and chain of custody documentation Graphs of TPHg, TPHd and MTBE concentrations in MW3 over time are included in Attachment C Summary • Groundwater levels at the site fell since the previous round of sampling During this event groundwater flowed in a east-southeasterly direction Flow direction at the site has historically been inconsistent • 1,2-DCA and EDB have not been detected in wells MW1 through MW3 since sampling began TPHg, TPHd, BTEX and gasoline oxygenate additives continue to be at non- detectable levels in wells MW 1 and MW2, and benzene was not detected in well MW3 for the second consecutive event • Although TPHd and TPHg in well MW3 increased during this quarter, their concentrations are generally decreasing MTBE concentrations in this well are consistent with historical analytical results Conclusions Groundwater flow direction remains variable at the site 1,2-DCA and EDB have not been detected in samples from wells MW through MW3 since sampling began, and do not appear to be present at the site 1n addition, TPHg, BTEX and TPHd have not been detected in wells MW1 and MW2 since sampling began Based on cumulative data the contamination plume appears to be localized in the vicimty of well MW3 Woolsey rht\gnw\2gm2002 doc