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r f � Second Quarter 2004 Monitoring Report Quik Stop Market No 121 Page 2 Groundwater Sampling As previously mentioned, CCI sampled all thirteen wells for the quarterly sample round 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 It should be noted the water table in the A-aquifer has risen approximately 2 feet from the levels reported during the January 2004 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), and for fuel oxygenates, including methyl tertiary butyl ether (MTBE), using EPA Test Method 9260B Summary of Laboratory Results For the first time since the site has been monitored, all thirteen wells were reported to be free of TPHg and BTEX compounds Only two of the ten(A-aquifer) shallow groundwater monitoring wells were found to be impacted with MTBE Perimeter monitoring wells MW-1, MW-2, MW- 4, MW-5, MW-7, MW-8, MW-11 and MW-12 were all reported to be free of detectable TPHg/BTEX and fuel oxygenates this quarter(Figure 2) Well RW-1, located in the center of the property, was reported to be free of detectable TPHg and BTEX compounds MTBE was detected at a concentration of 12 ug/L Monitoring well MW-3 was reported to be free of detectable TPHg and BTEX and was reported to contain 0 90 ug/L MTBE No other fuel oxygenates were detected in any of the other monitoring wells Two of the three deep wells, MW-9 and MW-10, screened from 65 to 75 feet within the B-