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Quik Stop Market No 121 CCI Project No 12118-3 Page 2 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, ethyl benzene and total xylenes (BTEX), using EPA Test Method 8015 and 8020 and MTBE using EPA Test Method 8260 Summary of Laboratory Results Groundwater samples collected from the site indicated all three wells (MW-1, MW-2 and MW-3) to have detectable TPHg contamination The laboratory reported monitoring well MW-1 to contain TPHg at 3,100 micrograms per liter(ug/1), MW-2 was reported to contain 70 ug/l TPHg and MW-3 was reported to contain 16,000 ug/l TPHg None of the wells were reported to have detectable concentrations of BTEX compounds The laboratory also reported the three monitoring wells to have detectable MTBE The highest concentrations of MTBE were reported in MW-3 at 43,000 ug/l Monitoring wells MW-I and MW- 2 were reported to have MTBE at concentrations of 5,700 ug/1 and 55 ug/l,respectively The results of the groundwater analysis are summarized in Table 2 The analytical reports from Entech and chain-of-custody documents are attached in Appendix B Discussion Groundwater measurements taken in the three onsite monitoring wells on April 6, 2000 indicated the depth-to-groundwater ranged from approximately 14 77 to 15 51 feet below the top of the well casings The water table has risen approximately 1 foot since the February confirmation sample round Groundwater contours in the vicinity of the three monitoring wells indicate the groundwater flow direction to be toward the south-southeast, at a relatively flat gradient of approximately 0 0005 feet per foot (Figure 2) The groundwater flow direction determined during this sample round is approximately the same flow direction reported in CCI's confirmation sampling conducted in February 2000 During sampling of the wells, a slight petroleum odor was noted in well MW-3 No unusual odors were noted in the other two wells Groundwater samples collected during this quarterly sample round indicate all three wells to contain detectable concentrations of TPHg and MTBE compounds In response to elevated levels of MTBE reported in well MW-3 last January and February, CCI pumped groundwater from well MW-3 using a vacuum truck The purpose was to remove as much of the MTBE concentrations in and around the well as possible . On March 30, 2000, CCI contracted Industrial Waste Utilization (IWU) of San Jose, California to pump water from the well Prior to pumping, CCI collected a water sample(MW-3A) from MW-3