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!1 .1 . Quik Stop Market No 121 CCI Project No 12118-2 Page 2 noted in well RW-1 Each well was purged of stagnant water prior to the collection of a sample It should be noted that the water table was found to be at much higher levels than the levels reported during the October 2001 sample round Many of the thirteen wells were found to have 5 to7 feet of water Monitoring well MW-8 was found to have approximately 4 feet of measurable water 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 data Table 1 Laboratory Analysis The groundwater samples were submitted to STL ChromaLab (ChromaLab), 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 fuel oxygenates including methyl tertiary butyl ether (MTBE), using EPA Prep Method 5030B and EPA Test Method 8260B Summary of Laboratory Results Six of the ten shallow groundwater monitoring wells (A-aquifer) were sampled and found to be impacted with petroleum hydrocarbons or MTBE Monitoring well MW-1, located on the northwest side of the site (Figure 2), near the intersection of Union Road and West Louise Avenue and monitoring well MW-2, also located on the north side of the site, were both reported to be free of detectable TPHg/BTEX compounds Monitoring well MW-2 was reported to have 17 micrograms per liter (ug/L) MTBE Monitoring well MW-3, located on the southeast side of the property, was reported to contain detectable TPHg, at 35,000 ug/L and no detectable BTEX compounds Monitoring well MW-3 was reported to contain MTBE at a concentration of 80,000 ug/L Recovery well RW-1, located near the east side of the fuel tanks, was also reported to have detectable TPHg, at 58,000 ug/L and no detectable BTEX compounds RW-1 was also reported to have 93,000 ug/L MTBE Monitoring well MW-4, screened from 33 to 43 feet in the A- aquifer, was reported to contain 3,300 ug/L TPHg and 9,300 ug/L MTBE Monitoring well MW- 5, located on the southwest side of the site, was reported to contain 81 ug/L TPHg and 5 2 ug/L MTBE Monitoring wells MW-1, MW-7, MW-11 and MW-12 were all reported to be free of • detectable petroleum hydrocarbons this quarter Monitoring well MW-8 was reported to have 1 ug/L MTBE