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Geological Technics lnc.� Page 3 Tank CIosure Report ' MCGranahan(Gawne Road) Project No.251.0 December 9,1994 characterization to evaluate the geology and the distribution of petroleum chemicals at this site. • The excavation was Iogged so that the geology could be correlated to ' hydrocarbon levels in the sampled soil. Supportive documents for the tank closure work are enclosed in Appendix A. 4.0 Soil Test Results and Discussion ' The following is a discussion of the soil samples and field observations. • The soil sample from the stockpile registered non-detect gasoline and had only a trace of BTEX constituents (Xylene Q 4.0 gg/Kg). • There were, however, high levels of both gasoline and BTEX type hydrocarbons within the tank pit at 10 feet and 17.5 feet. (Laboratory data sheets are attached in Appendix B). Sample I.D. Benzene Toluene E. Benzene Xylene Gasoline mg/Kg mg/Kg mg/Kg mg/Kg mg/Kg SS Q 10' 51.0 52.4 28.4 157.0 2310 SS Q 17.5' 0.96 11.6 1.3 77.2 820 Stockpile ND<0.003 ND<0.003 ND<0.003 0.004 ND<1.0 tDetection limits: ' Three main units observed(See field log; Appendix C) within the tank pit include: 1) Sandy-clay, red to reddish gray brown, some fine sands from 0-6.0 ft. 2) Silty-sand, yellow-brown, medium grained, fairly well sorted from 7-14 ft. 3) Heavy clay hardpan, grayish from 14 ft on. 5.0 Conclusions and Recommendations Given the data gathered during the tank closure work presented above, Geological Technics Inc. concludes that an unknown amount of gasoline was ' released from this tank. The soil test data from 10 and 17.5 ft in the tank pit suggest that the petroleum content of the soil is not attenuating rapidly enough to justify going directly into a remedial excavation program.