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9 <br /> custody. <br /> The split-spoon samplers were washed with Tri-Sodium Phosphate (TSP) between each soil <br /> sample collection, and all drilling and sampling equipment, including the HydroPunch, was <br /> steam-cleaned between boreholes to prevent cross-contamination. The HydroPunch also <br /> contains an inlet screen cartridge (to reduce the influx of sediment into the device) that is <br /> disposed of with each use. The soil samples in the remaining brass sleeves at each depth <br /> interval were used to screen for volatile organics with a organic vapor meter (OVM). The <br /> boreholes and drill cuttings piles were also monitored with the OVM during drilling. All <br /> samples were collected, and sampling observations and soil descriptions recorded on field <br /> log sheets, by LSCE's Certified Engineering Geologist. Following collection of a ground- <br /> water sample, each borehole was backfilled with a cement-bentonite grout All drill cuttings <br /> were contained in visqueen, which in turn were secured by labeled 55-gallon drums <br /> containing the decontamination water. <br /> All the soil samples were analyzed for selected total metals (copper, lead, mercury and <br /> zinc). The soil samples below a depth of 1-1/2 feet were analyzed for total petroleum <br /> r oil and diesel, and benzene, toluene, ethylbenzene and <br /> hydrocarbons (TPH) az motor 1, <br /> yd <br /> xylenes (BTEX) by EPA modified Method 8015. The soil sample containing the highest <br /> concentrations of the above selected metals was also analyzed for soil pH and soluble metal <br /> concentrations (citric acid WET for each metal, plus deionized water analysis for lead). The <br /> ground-water samples were analyzed for TPH-motor oil and diesel and BTEX by EPA <br /> modified Method 8015. Both soil and ground-water samples were also scanned for TPH- <br /> gasoline (during the TPH analyses) and naphthalenes (during the BTEX analyses). <br /> Results <br /> The soil lithologies encountered during drilling of the four borings were consistent across <br /> the parcel, t}pically with seven to eight feet of clayey silty sand overlying silty clays. Ground <br /> water was generally encountered in the silty clay at depths of 23 to 25 feet However, tre <br /> analytical results from the samples collected indicated that the extent of contamination in <br />