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a O � Tank 2 had holes in it and soil contamination was evident at the time of removal Groundwater occurred roughly 8 to 10 feet below the surface Approximately 190 cubic�'� yards of contaminated soil was excavated, and 3,225 gallons of groundwater with a thin layer of floating product was pumped from the excavation Analytical testing showed that total Petroleum Hydrocarbons as Gasoline (TPHG) was detected in soil and groundwater samples, and total Petroleum Hydrocarbons as Diesel was not detected in any sample Wright recommended and City initiated interim remediation since roadway curb and sidewalk was being realigned directly over where tanks were removed and gross obvious contamination would be unaccessable once roadway realignment was completed Following the soil excavation, the roadway, curbs and sidewalk were realigned due to construction of a right hand turn lane from eastbound Grantline Road to southbound Holly During the removal of T-1 through T-5, the former property owner informed Wright that the City acquired the property for realignment of Grantline Road and tanks T-1 through T-5 were not known to have been present Also the property owner reported two additional tanks had been removed at an earlier date from his property at the east side of the building (What is now Tracy Auto Stereo) Field Methods Exploratory Borings Six exploratory borings were drilled at the site (Figures 1, 2 and 3) The borings were positioned to ascertain distribution of the contaminants in soil and groundwater under the site given the constraints of the site, numerous underground utilities including a large Chevron Oil pipeline and relocated curbs and roadways Drilling permits were secured from the PHS-EHD, and all utilities were cleared prior to doing the fieldwork The borings were used to define the uppermost aquifer strata, and borings were advanced to the contact and into the underlying lower confining strata (where boreholes were terminated) in soil excavation area Flowing conditions were encountered in some boreholes causing some soil samples to be lost Drilling continued until the driller called sampler rod refusal to advance A PHS-EHD representative observed portions of the work The boreholes were drilled with truck mounted hollowstem auger and/or direct push drilling equipment All drilling equipment and sampling tools were cleaned prior to arriving, and before leaving the site The augers were advanced to the desired sampling depth interval, and a drive split spoon sampler were driven ahead of the drill bit The sampler was then retrieved and dissembled, and the soil filled brass or acetate liners, if retained for chemical analysis, were sealed with Teflon®paper and plastic endcaps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest on crushed ice Page 2