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• Fourth Quarter 2003 Monitoring Report Quik Stop Market No 121 Page 2 Groundwater Sampling As previously mentioned, CCI sampled nine of the thirteen wells for the quarterly sample round Prior to groundwater 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 However, ozone was noted upon opening well MW-4 Each well was purged of stagnant water prior to the collection of a sample It should be noted that the water table has dropped approximately 15 feet from the levels reported during the July 2003 sample round Normal field measurements, including pH, conductivity, water temperature and dissolved oxygen, 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 8015M and 8021B Test Methods and for fuel oxygenates, including methyl tertiary butyl ether(MTBE), using EPA Prep Method 5030B and EPA Test Method 8260B Summary of Laboratory Results Only one of the six shallow groundwater monitoring wells (A-aquifer) was sampled and found to be impacted with petroleum hydrocarbons or MTBE Perimeter monitoring wells MW-2, MW-4, MW-11 and MW-12 were all reported to be free of detectable TPHg/BTEX and fuel oxygenates this quarter( Figures 2) Monitoring wells MW-1, MW-3, MW-7 and MW-8 were all found to be dry this quarter Well RW-1, located in the center of the property, was reported to contain detectable TPHg, at 1,400 micrograms per liter(ug/L), no detectable BTEX compounds above the detection limit, and MTBE at a concentration of 1,700 ug/L Monitoring well MW-4, screened from 33 to 43 feet in the A-aquifer, was reported to be free of detectable TPHg/BTEX and MTBE compounds