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f b s• Second Quarter 2005 Monitoring Report Quik Stop Market No 121 Page 2 gasoline (TPHg), benzene, toluene, ethylbenzene and total xylenes(BTEX) and fuel oxygenates Groundwater samples were collected from the site wells in accordance with COI's Groundwater Sampling Protocol (Appendix A) The groundwater purged from each well and equipment rinse water were placed in a 55-gallon drum and left at the site A summary of the groundwater purge data is presented in Table 1 Groundwater Sampling As previously mentioned, CCI sampled 12 of the 13 wells for the quarterly sample round Monitoring well MW-12 was measured for water level data only this quarter Prior to sampling, CCI measured the depth-to-groundwater using an electronic sounding tape and field-checked the wells for the presence of free-floating product by collecting a sample in a clear acrylic bailer Free-floating product was not observed Each well was purged of stagnant water prior to the collection of a sample Dissolved oxygen measurements were also taken this quarter Normal field measurements, including pH, conductivity, and water temperature, were periodically recorded during the purging process A sample was collected when these parameters stabilized to within 10% of each other After the groundwater was purged from each well, the groundwater samples were (a) collected with a clean disposable bailer, (b)transferred to appropriate laboratory-supplied bottles, (c) labeled, (d) logged on a chain-of-custody form, and (e) placed in a chilled ice chest for transportation to a state-certified laboratory Monitoring well purge data are summarized in Table 1 Laboratory Analysis The groundwater samples were submitted to Severn Trent Laboratories, Inc (STL), a state- certified laboratory located in Pleasanton, California, for chemical analysis The laboratory employed methods approved by the California Regional Water Quality Control Board (CRWQCB) and the EPA The groundwater samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) and benzene, toluene, ethylbenzene and total xylenes (BTEX), using EPA Test Method 8015M/8021 and for fuel oxygenates, including methyl tertiary butyl ether (MTBE), using EPA Test Method 8260B Summary of Laboratory Results The laboratory reported all ten A-aquifer wells sampled this quarter to be free of TPHg and BTEX compounds None of the ten A-aquifer groundwater monitoring wells were found to be impacted with MTBE Monitoring wells MW-1, MW-2, MW-3, MW-4, MW-5, MW-7, MW-8, MW-11 and RW-1 were all reported to be free of detectable TPHg/BTEX and fuel oxygenates •