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All soil samples collected were taken under chain of custody to American Environmental Network Laboratory (AEN) The samples were analyzed for TPH-E using EPA Method 3550/Modi6ed 8015, and BTEX compounds using EPA Method 8020 ' After completion of soil sampling, the borings were abandoned (with the exception of Boring MW-5, which was completed as Monitor Well MW-5) in accordance with San Joaquin County Department of Public Works guidelines The boreholes were grouted through tremie pipe to the ground surface under supervision of San Joaquin County Environmental Public Health Services, Environmental Health Division personnel. Waste soils produced by the drilling and sampling activities were placed in 55-gallon drums, which were labeled, and are presently stored on site 3.1.1 Vertical Boring (VB01) The vertical boring (VB01) was drilled near the northwest corner of the Tank #4 excavation area (Figure 2) The boring was drilled to a total depth of 41 feet bgs and was sampled approximately every 5 feet The boring log for VB01 is shown in Appendix B. The HNU-PID field screening results, and analytical results for each soil sampling ' interval of Boring VB01 are summarized in Table 1. Hard copies of the analytical data are presented in Appendix C No benzene was detected in the soil samples from this boring ' Toluene was detected in all but the 5-foot deep sample and ranged from 6 to 24 µg/kg, with the greatest concentrations detected in the 15- and 20-foot samples. Diesel-range ' hydrocarbons were detected in the 5- through 20-foot samples ranging from 2 to 15 mg/kg, with the greatest concentrations detected in the 10- and 15-foot samples Motor oil-range, ' hydrocarbons were detected in the 5- through 20-foot samples ranging from 10 to 72 mg/kg, with the greatest concentration detected in the 10-foot sample 1 3.1.2 Slant Boring (SBOI) ' The slant or angle boring (SB01) was drilled near the mid northern portion of the Tank #4 excavation area (Figure 2) The boring was drilled at an approximate 30 degree angle to the vertical axis or a 60 degree angle to the horizon The total auger depth of the boring was 41 feet bgs, which is equivalent 35 5 feet deep. The boring was sampled every ct4,� +, crpi 5