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JUJ/i-K LUI-2 <br /> Wdward-Clyde Consultants <br /> water surface. Furthermore, a sample of the water (GW-1) was taken and <br /> found total petroleum hydrocarbons (TPH) and benzene, toluene and xylene <br /> (BTX) concentrations to be below the detection level of 1.0 and 0.05 mg/1 , <br /> respectively. A copy of the lab results is appended to this report. The <br /> contamination noted during tank removal was, therefore, thought to be the <br /> result of an occasional overfill . <br /> Remedial Actions <br /> The assumption that only minor contamination was present and the potential <br /> urgency of the situation resulted in a decision to forego additional <br /> investigation and excavate the contaminated material . The excavated <br /> material was to be aerated onsite. The regional air board was contacted <br /> but no permit was required to aerate material below 50 mg/kg TPH. The <br /> initial excavation was performed on October 13, 1986 where approximately 40 <br /> cubic yards of material were removed. Only about 5 to 10 yards were <br /> thought to contain significant hydrocarbon levels as the contamination <br /> appeared to be limited to a 1-to-2-foot thick zone that was just below the <br /> water table (5.5 to 6 ft below grade). The majority of the material <br /> removed was clean overburden. The excavation extended below the vertical <br /> extent of contamination (7 to 8 ft) and well beyond the lateral extent to <br /> the north, east and northwest. Some odor was still present along the <br /> southern end of the excavation and was more apparent in the southwest <br /> corner. The loading dock driveway and gasoline dispensing pump prevented <br /> further excavation in those areas. It was decided to remove the pump and <br /> continue excavation at a later date. <br /> Three soil samples were taken from the excavation for laboratory <br /> analysis. E-1 was taken at a depth of 6.4 ft along the southern wall near <br /> the southeast corner. E-2 was taken from the bottom of the excavation <br /> (8 ft) near the center, while E-3 was taken from a depth of 7 ft near the <br /> northwest corner. Sampling locations are shown in Figure 1. The samples <br /> were analyzed for TPH (gasoline) and BTX. A copy of the lab report is <br />