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t t11 r First Quarter 2003 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 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 a slight product odor was noted in well RW-1 In addition, ozone was noted upon opening wells MW-1 and MW-3 Each well was purged of stagnant water prior to the collection of a sample It should be noted that the water table has risen approximately 2 to 4 feet from the levels reported during the October 2002 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 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 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 Four of the ten shallow groundwater monitoring wells (A-aquifer) were sampled and found to be impacted with petroleum hydrocarbons or MTBE Parameter monitoring wells MW-1, MW-2, MW-7, MW-8, MW-II and MW-12 were all reported to be free of detectable TPHg/BTEX and fuel oxygenates this quarter ( Figures 2 and 3) Well MW-3, located on the southeast side 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, MTBE at a concentration of 2,600 ug/L and tert butyl alcohol(TBA) at 2,500 ug/L Recovery well RW-1, located near the east side of the fuel tanks, was reported to have detectable • TPHg, at 13,000 ug/L, and no detectable BTEX compounds above the detection limit RW-1 was also reported to have 21,000 ug/L MTBE and 5,500 ug/L TBA Monitoring well