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Mr Michael Infurna Page 2 Prior to sampling, monitoring wells MW 1 through MW3 were purged of a n uvmum of three well casing volumes During the purging process the physical parameters of temperature,pH and electrical conductivity were measured As well MW3 was bung purged a slight sheen developed Samples were collected after the physical parameters stabilized and water level recovered 100% Purge water was contained M appropriately labeled DOT-approved 55-gallon drums, and is currently bung 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 IDB using EPA method 8260 GROUNDWATER ANALYTICAL RESULTS No detectable levels of TPHg, TPHd, BTEX, or gasoline oxygenate additives were present in the samples collected from wells MWl and MW2 1,2 DCA and EDB were not detected in any site wells In the sample collected from MW3, MTBE was detected at a level of 1,200 parts per billion (ppb), and benzene was detected at 10 ppb TPHg and TPHd were reported at concentrations of 2,900 ppb and 20,000 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 have decreased since the last round of sampling • Since the previous monitoring event groundwater flow reversed from a southeasterly direction to a northwesterly direction • Wells MW 1 and MW2 continue to show non-detectable levels of target analytes • In well MW3, the concentrations of TPHg, BTEX, and MTBE decreased by approximately 50% since the previous sampling while the levels of TPHd increased an order of magnitude CONCLUSIONS No target analytes have been detected in either well MWI or MW2 since sampling began Contaminant concentrations at the site appear to have a direct relationship with groundwater level fluctuation. Analytical results from previous quarterly events showed a reduction in contaminant concentrations In well MW3 as the water level at the site rose, and an increase in concentrations as the water level fell During thus event, water levels at the site decreased,and the concentration of TPHd in well MW3 increased Woolsey chtlgmrWgm2000 doe