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Mr Michael Infurna 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 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 (ELAP #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 Monitoring Well Surveying As required by AB 2886, all monitoring wells were surveyed by a Registered Surveyor to a horizontal accuracy of less than one meter and a vertical accuracy of 0 01 feet In January 2002, Morrow Surveying surveyed the latitude and longitude of the site wells relative to the North American Datum (NAD83), and surveyed the wellhead elevations relative to City of Stockton Benchmark No 186/Cal-Trans Benchmark No RM 90 A site map showing monitoring well locations, latitude and longitude coordinates and wellhead elevations is included in Attachment B Groundwater Analytical Results . 1,2 DCA and EDB continue to be at non-detectable levels in wells MWI through MW3, and no detectable concentrations of TPHg, TPHd, BTEX, or gasoline oxygenate additives were present in wells MW l and MW2 In well MW3, benzene was not detected, and no gasoline oxygenate additives were detected except for MTBE, which was detected at a concentration of 1,300 parts per billion (ppb) TPHg was detected at a concentration of 500 ppb, and TPHd was detected at a concentration of 460 ppb Analytical results are summarized in Table 2 Attachment C contains laboratory reports and chain of custody documentation Summary Groundwater levels at the site rose since the previous round of sampling During this quarter groundwater flow remained in an east-northeasterly direction, however, flow direction at the site has historically been inconsistent 1,2 DCA and EDB have not been detected in wells MW I through MW3 since sampling began TPHg, TPHd, BTEX and gasoline oxygenate additives continue to be at non- detectable levels in wells MW1 and MW2, and benzene was not detected in well MW3 TPHd and TPHg in well MW3 appear to have formed decreasing trends while MTBE concentrations are consistent with historical analytical results Benzene levels at the site continue to be less than the established maximum contaminant levels (MCL) for drinking water Woolsey chtlgmrllgrn2002 doc