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• Quik Stop Market No 121 CCI Project No 12118-2 Page 2 I was 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 at approximately the same level as that reported during the January 2002 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 6-inches of water, however, the amount was in sufficient to collect samples therefore, no sample was collected from this well 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 STL San Francisco (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 8021 B 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 Five of the nine 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, 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 , however, MW-1 was reported to contain 2 7 micrograms per liter (ug/L) MTBE (Figure 2 and Figure 3) Monitoring well MW-3, located on the southeast side of the property, was reported to contain detectable TPHg, at 100,000 ug/L, MTBE at a concentration of 130,000 ug/L and no detectable BTEX compounds above the detection limit Recovery well RW-1, located near the east side of the fuel tanks, was also reported to have detectable TPHg, at 120,000 ug/L and no detectable BTEX compounds above the detection limit RW-1 was also reported to have 150,000 ug/L MTBE Monitoring well MW-4, screened from 33 to 43 feet in the A-aquifer, was reported to contain 640 ug/L TPHg, 760 ug/L MTBE, and no detectable BTEX compounds Monitoring well MW-5, located on the southwest side of the site, was reported to be free of detectable TPHg and BTEX compounds but contained 14 ug/L MTBE