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i ( Appendix A) . Each well was equipped with a threaded plug at the bottom and a slip cap at the top. The annular space around the screen was partially filled with natural sand pack. . (except in well EA4 ) and with #3 Monterey sand up to about 3 feet above the screen. The sand pack was sealed with 3 feet of bentonite pel- lets and a cement grout to the surface, using a tremie pipe and Dump. The wellhead was secured with a frame locker and a steel CN7-type monitoring well cover, which is watertight and protects the well from unauthorized entry. Each well also had a well tag with the well depth, screened interval, and well number. After completion, each well was gauged and surveyed, and its location was determined in relation to the property boundaries. 2 . 1 .2 Soil and Ground-Water Sam lin Soil Sampling f ~ During drilling. soil samples were collected at 5-foot intervals from each borehole, using a 2.5-inch split-spoon sampler lined with three 6-inch-long brass liners. After collection the lowest liner was immediately covered with aluminum foil, capped, taped, labeled, and placed in a cooler on ice. The remaining part of each sample was used for soil classification, and for detection of hydrocarbons using a Foxboro volatile organic analyzer (VOA) . The sampler was thoroughly cleaned with trisodium phosphate solu- tion and rinsed with clean tapwater and distilled water between samplings to prevent cross-contamination. Samples collected just above the ground-water table and those that contained hydrocar- bons, on the basis of VOA or olfactory indication, were shipped under chain of custody to the laboratory of Anametrix, Inc. , for analysis. Gauging and Ground-Water Sam lin On 17 February 1988, all previous and new monitoring wells were gauged to the top of the PITC casing. The new wells were purged c23/72g2 5