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LH LEEDSHILL HERKENHOFF, INC laboratory, samples were cooled to 4° Celsius at the site and maintained at that temperature until they were received at the laboratory. Prior to transport, the samples were logged onto a chain-of-custody form identifying the project number, sample type, container type, sample identification, sampler and date ' The samples were picked up by Superior Analytical , Inc. , where a laboratory representative signed the chain-of-custody form. The samples were then placed in a refrigerator until they were extracted and analyzed prior to their expiration date. 3,5 GEOLOGIC CROSS-SECTIONS Geologic cross-sections were prepared based on lithologic information obtained from the drilling of TBS, TB6, TB7, TBB, TB9, MW4 and MWS. The Unified Soil Classification System was used to classify the soils. In both the soil boring and monitoring well installations, discrete soil samples were taken every 5 feet using the modified split-spoon sampler. An additional sample was collected at 2'/2 feet. The drill cuttings were continuously observed to verify the discrete sample classifications made at five-foot intervals. A continuous sampling technique, described in Section 3.1, was used on TB6. Soils in this area generally consist of low plasticity silts, clays, and fine sands with some clayey silts and silty clays. In section A-A', Figure 5, an organic fill material exists at a depth of two to five feet below the backfilled silt and gravel zones. However, this organic fill does not extend much beyond TB6 in a south westerly direction. At the northern end of the site, low plasticity clays exist from 5 to 10 feet below ground surface overlaying a 2-foot thick fine sand layer. Soils then grade into low plasticity clayey silts and silts of medium brown color Frith intermittent clay and sand lenses down to 50 feet. From 50 to 60 feet, the soils consist of intermittent sand and silt layers, with a very hard, well compacted clay layer at 60 feet. Figure 6 presents a nest to east geologic cross-section along the northern boundary of the site. Soils in the southern section of the property consist of low plasticity clays, silty clays, and clayey silts to a depth of 15 feet. These soils grade into a red-brown silt that exists from a depth of 20 feet down to 40 feet. The silt is uniform with depth, containing some clay particles, and increasing in moisture content with depth. At a depth of 40 feet, the soil becomes a poorly graded fine brown sand. Grain size and clay content of this fine sand layer varies to a depth of 65 feet. Groundwater was encountered in MW4 and MW5 at 53 feet. 306 SAMPLE ANALYSIS Soil samples were collected from each of the seven borings and analyzed for BTX&E and TPH as gasoline (except for TB5 which also had two samples analyzed for TPH as diesel ) . After the first round of analyses, a number of confirmation analyses were performed to verify the results Soil grab samples were collected from the soil stockpile on November 9, 1989 and from BCA drums on December 7 and