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unable to reach the required reporting limit of 0 . 005 mg/kg for ,• benzene. It is likely that benzene is present at , a concentration somewhere between the reporting limit of 13 mg/kg and 0 . 005 mg/kg. The laboratory results confirm the field observation that contamination was limited to the south end of dispenser island #2 . Based on this evidence, Upgradient has prepared this work plan to overexcavate the contaminated soil in the area around sample JL-P- 3 . The soil will be loaded into dump trucks and transported to REMCO in Richmond, California for disposal . 2 .0 EXCAVATION PROCEDURES Excavation will be performed by Bob 'Evans Trucking under the supervision of Upgradient Environmental . An excavator will be used to enlarge and deepen the piping trench until no further evidence of contamination is observed. Upgradient will use a portable photo- ionization detector (Microtip model HL-2000) to screen the excavated soil and direct the equipment operator. when no further evidence of contamination is detected, the excavator will be used to expose fresh soil on the walls and floor of the excavation, and Upgradient will use a slide hammer to collect soil samples from the excavator bucket. The sample liner will be removed from the sampler, covered with teflon sheets , capped, sealed, and placed on ace for transmittal to Excelchem Labs . The samples will be analyzed • for TPH-g and BTEX. One sample will be collected for every 20 lineal feet of excavation. The dimensions of 'the excavation cannot be reliably estimated at this time, but it is anticipated that the trench will be deepened to at least 10 feet. The excavation will remain open pending results from the laboratory. If no contamination is detected in the samples, the new tanks and dispensers will be installed and the excavation will be backfilled and graded in accordance with regulatory requirements . We anticipate using soil previously excavated from the new and old tank cavities . Five samples were collected on November 8 from the tank stockpile . Excelchem composited these to one and analyzed it on 24-hour turnaround for TPH-g and BTEX. ,No hydrocarbons were detected ( see attached laboratory report) . Upgradient will report the results of this investigation when all field and laboratory work is completed. The report will be prepared in accordance with the Tri-Regional. Board Recommendations for Investigation of Underground Tank Sites and signed by a California registered geologist .