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90343TEXT CON-3 • . Soil samples were collected for laboratory determination of total petroleum hydrocarbons and to provide information on subsurface stratigraphic conditions. Three sets of samples were taken at three foot intervals beginning at a depth of 3 feet below grade (3 to 4.5 ft; 6 to 7.5 ft; and 9 to 10.5 ft) . The samplers were collected using a 2.5 inch diameter by 18 inch long modified California sampler containing three brass tubes 2.5 inches in diameter and six inches long. The sampler was driven ahead of the augers to the desired depth by dropping a 140 lb. hammer approximately 30 inches. The average number of blows (blow count) required to advance the sampler over a 12 inch increment of the sample interval were recorded on the boring log. The sampling equipment was cleaned with a low phosphate detergent and deionized water rinse between each sample drive. After each drive the sampler was removed from the boring and disassembled. In general the bottom tube from each drive was retained for analysis. The tubes were sealed with aluminum foil , a PVC end cap, electrical tape and stored on ice in a cooler until shipment to the laboratory. In a few samples, only partial recovery was achieved in the bottom tube in which case the middle tube was retained for analysis. The samples were numbered according to boring, sample location and tube number. For example the third (bottom) tube from the first sample drive (3.0 to 4.5 ft) in Boring 2 would be labeled B2-1-3. Of the 12 samples collected, eight were selected for laboratory analysis. Sample selection was based primarily on the potential for contamination. All three samples from Boring 2 were selected due to its location within the spill area. The samples from the lower two drives in Borings 1 and 3 were selected to assess potential hydrocarbon migration both through the soil and along the water table. Because the distance from the source was expected to preclude lateral migration through the soil , only the sample just above the water table in Boring 4 was retained for analysis. Standard chain-of-custody procedures were used to track the collection and shipment of samples.