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. Soil from the second ring is used for field analysis of possible hydrocarbon contamination. The sample is placed in a ziplock bag, sealed, and allowed to volatilize for olfactory inspection and scanning by use of a portable organic vapor meter (OVM). A head-space measurement is taken by breaking the seal just enough to insert the probe. The highest reading is recorded; however, if the reading stabilizes at a significantly different level, this is also noted. These readings are used to qualitatively determine the presence or absence of soil contamination. The OVM has a detection range of 0.1 ppm to 1,000 ppm for hydrocarbon vapors, when calibrated with a hexane standard. Soils in the remaining rings are examined to complete the field descriptions. This data includes a written soil description, classification using the Unified Soil Classification System code, and observations of any notable odors, staining or contamination. Also noted are unusual drilling conditions for future reference. All data are recorded on the boring logs. The minimize cross contamination, the augers are steam-cleaned prior to drilling each boring The split-spoon sampler is cleaned using a three step process commonly referred to as a "three- bucket wash". This consists of first a trisodium-phosphate wash, followed by a tap water rinse, and finally, a deionized water rinse. This process is performed between each sample run. All cuttings and excess sample material recovered during the drilling operations are placed in 55-gallon DOT hazardous waste drums pending laboratory analysis results The drums are sealed, labeled, and left on site for proper disposal. SOIL SAMPLING 1. Undisturbed (intact) soil samples are recovered from all borings utilizing brass tubes in a split-spoon sampling tool, or continuous core sampler. 2. Soil samples are taken at a minimum interval of 5 feet or at significant changes in lithology beginning at the ground surface. 3. Borings are drilled and sampled by techniques that do not introduce liquids into the boring and that allow accurate detection of saturated zones, perched groundwater, and the water table. 4. All materials encountered during drilling are described in detail.