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Additional Investigation to Define the Extent of Groundwater Contamination <br /> Quik Stop Market No 121 <br /> Page 6 <br /> The data from the pumping well (RW-1) were analyzed by the Neuman solution for unconfined <br /> aquifer with partial penetration of the well The average value of K for the pumping and recovery <br /> test is 0 0033 centimeter per second (cm/s) or 0 0064 feet per minute (ft/min) <br /> Laboratory Analysis <br /> CCT submitted a total of 16 soil samples and 4 water samples to Entec Analytical, Inc of Santa <br /> Clara, California, a state-certified laboratory, for analysis All samples were analyzed for total <br /> petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene and xylenes (BTEX), <br /> using EPA Test Methods 8015 and 8020, and fuel oxygenates using EPA Test Method 8260 <br /> Results of the soil and groundwater sample analysis are summarized in Tables 2 and 3 The <br /> laboratory reports and chain-of-custody forms are attached in Appendix D <br /> Discussion <br /> Soil Conditions <br /> A review of the soil sample analyses collected from monitoring wells MW-9, MW_10 and MW-I 1 <br /> indicated 15 of the 16 soil samples were reported to be free of detectable petroleum hydrocarbons <br /> Soil sample MW-I 1-30, Iocated on the northeast side of the site, was reported by the laboratory to <br /> contain 12 micrograms per kilogram (ug/kg) methyl tertiary butyl ether (MTBE) No other soil <br /> samples were reported to contain detectable TPHg/BTEX or fuel oxygenate compounds Results <br /> of the soil sample analysis are summarized in Table 3 <br /> Groundwater Conditions <br /> CCI collected a total of four groundwater samples from the three onsite deep wells (MW-6, MW-9 <br /> and MW-10) and from shallow well MW-11 The laboratory reported all four wells to be free of <br /> detectable TPHg and BTEX compounds The laboratory also reported three of the four wells to be <br /> free of detectable fuel oxygenate compounds Monitoring well MW-6 was reported to contain 32 <br /> micrograms per liter (ug/1) MTBE No other compounds were reported in this sample Results of <br /> the groundwater analysis are summarized in Table 2 <br /> Conclusions and Rccommendations <br /> CCI has completed the installation of two additional deep wells and one additional onsite shallow <br /> well, groundwater in the vicinity of the two new deep wells (MW-9 and MW-10) and the new <br /> shallow well MW-11 are free of detectable petroleum hydrocarbons <br /> A review of the site hydrogeology data indicates monitoring wells MW-6, MW-9 and MW-10 are <br />