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CJeologtcalTechnus Inc Page 7 Soil Investigation Report Bank of Stockton Project No 443 2 June 19, 1996 In boring B5, the was no petroleum odor to a depth of 7 feet, where a the base of backfill material was encountered The native material below 7 feet had a very strong odor During the drilling of the borings Bl, B2, and B4, there was a strong odor of what seemed to be gasoline beginning at as little as 2 to 3 feet below the surface This odor extended to the bottoms of all of the borings except B3 which is at the site of the former 2,000 gallon AST No gasoline odor or other evidence of petroleum hydrocarbons was detected in B3 Total Petroleum Hydrocarbon as gasoline (TPH-G) of up to 7,780 ppm was found in I sample B4-10', and 5530 ppm was found in sample B5-10' A total of 5,730 ppm of diesel range petroleum (TEPH-D) was found in sample B1-10' which lies at the suspected position of the former pump island BTEX compounds were also found in all the samples except sample B3-10' No MTBE was found in the two samples in which it tested for, and only a low level of total lead (12ppm) was encountered Lead is a naturally occurring element found in most soils, and it can naturally exceed 20 ppb It is not known if the level actually detected represents any elevation over background levels A summary table of analytical results is attached as Appendix B and copies of the laboratory analytical reports are attached as Appendix C ' 4.4 Hydrocarbon Distribution in the Groundwater ' As was stated above, the nearby domestic water well was sampled in November of 1995 and again on December 7, 1995 and it was found to contain detectable levels of gasoline range petroleum hydrocarbons The initial sample collected after about 3 to 5 minutes of pumping was found to contain 624 ppb of gasoline range hydrocarbons and 206 ppb of benzene The follow-up sample was found to contain no detectable TPH but it did not contain 6 ppb of benzene It is not known if petroleum hydrocarbons occur directly beneath the site of the oil supply building and soil borings 4.5 Water Well- Downhole Television Survey ' Based on the results of the television survey, it was found the that groundwater surface occurs at about 35 feet below grade The water from 35 feet to 45 feet was so dark and murky that no useful images were obtained in tlus interval Below 45 feet, the water cleared sufficiently to obtain images although considerable sawdust or small wood chips were found to be suspended in the water The camera was