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Mr Michael Infurna Page 2 No 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 98% of pre-purge levels 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 using EPA method 8260 GROUNDWATER ANALYTICAL RESULTS No detectable concentrations of TPHg, TPHd, BTEX, or gasoline oxygenate additives were present in the samples collected from wells MW 1 and MW2 In well MW3, benzene was detected at a concentration of 0 7 parts per billion (ppb) TPHg was detected at a concentration of 650 ppb, a 50% decrease since the last monitoring event TPHd and MTBE were reported at concentrations of 1,200 ppb and 1,300 ppb, respectively No other oxygenate additives were detected in the water sample from well MW3 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 previous round of sampling Groundwater flow switched to a east-northeasterly direction during this quarter Flow direction at the site has historically been inconsistent • TPHg, TPHd, BTEX and gasoline oxygenate additives continue to be at non-detectable levels in wells MW1 and MW2 • Concentrations of TPHd and TPHg in well MW3 continue to decrease compared to previous sampling events TPHg decreased 50% since the last event, and has formed a decreasing trend Benzene was detected, however, the concentration continues to be less than the established maximum contaminant levels (MCL) for drinking water TPHd appears to be forming a decreasing trend while MTBE levels are consistent with historical analytical results CONCLUSIONS No target analytes have been detected in either well MW1 or MW2 since sampling began Analytical results in well MW3 from previous quarterly events showed a general reduction in contaminant concentrations as the water level at the site rose, and an increase in concentrations as the water level fell During this event, however, water levels at the site fell and concentrations of TPHd and TPHg, decreased A general trend of decreasing contaminant concentrations over the last year is apparent in well MW3 Woolsey chtlgmr14gm2001 doc