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Monitoring Well Installation Report Quik Stop No 121 Page 6 nearest 0 01 feet and corrected to mean sea level The data from the surveyor is included Appendix C Laboratory Analysis Soil and groundwater samples collected from the well installations were submitted to North State Environmental (North State), a state-certified laboratory located in South San Francisco, California, for chemical analysis North State employed methods approved by the California Regional Water Quality Control Board (CRWQCB) and the EPA All 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 The soil and water samples were also analyzed for oxygenates following EPA 8260 Test Method A copy of the laboratory reports and chain-of-custody reports are attached in Appendix D Soil and Groundwater Chemical Analysis CCI submitted 9 soil and 3 water samples to North State for analysis All 9 soil samples were reported by the laboratory to be below the laboratory detection limits for TPHg/BTEX However, all 9 soil samples were reported to have detectable concentrations of the fuel oxygenate methyl-tert- butyl ether(MTBE) MTBE concentrations were reported to range from a low of 10 micrograms per kilogram (ug/kg) in soil sample MW-1-10 to a lugh of 88 ug/kg in sample MW-1-20 Table 1 presents a summary of the soil analysis results Groundwater samples collected from the three on-site monitoring wells revealed low levels of petroleum hydrocarbon contamination in all three wells Monitoring well MW-1 and MW-2 were reported to have detectable TPHg contamination, at 140 micrograms per liter (ug/1) and 82 ug/l, respectively No other TPHg/BTEX compounds were detected in these two wells Monitoring well MW-3 was reported to have low levels of toluene (1 ug/1), ethylbenzene (1 ug/1) and total xylenens (4 ug/1) No TPHg or benzene compounds were reported in this water sample All three water sample were reported to be free of detectable levels of MTBE Table 2 presents a summary of the water sample analytical results Copies of the laboratory reports and chain of custody documents are attached in Appendix D Discussion CCI installed three groundwater monitoring wells in the vicinity of the fuel tank complex at Quik Stop Market No 121 to monitor groundwater conditions and establish a groundwater flow direction at the subject site Soil samples collected during the investigation were found to be composed of silty sand extending from near the surface to depths of approximately 6 to 9 feet In general, the soil