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FIELD PROCEDURES Three soil borings will be drilled to an anticipated depth of 85 feet below surface grade using a truck-mounted drill rig equipped with hollow-stem augers. All drilling equipment will be steam cleaned between borings to reduce the potential of cross-contamination; rinse water generated during steam cleaning will be pumped into labeled 55-gallon drums and stored on site. All soil cuttings generated during drilling will be placed on and covered with plastic. Soil samples will be obtained at maximum intervals of five feet and/or at significant stratigraphic changes beginning at 5 feet below grade and continuing to the total depth of the borings. Soil samples will be obtained with a modified California sampler containing clean two-inch diameter, six-inch long brass tubes. All sample tubes will be sealed with Teflon® sheets, plastic caps, duct tape, and preserved on ice. Soils encountered during drilling will be logged in the field by a qualified geologist or engineer using the Unified Soils Classification System. Each sample will also be field screened using a photo ionization detector(PID) and observations of our field geologist or engineer to assist in selecting soil samples for laboratory analysis, if warranted. A diagram showing construction details of the proposed ground water monitoring wells is shown on Plate 4. The wells will be developed using a vented surge block. Subsequent to surging, the wells would be purged until stabilized pH, temperature, and conductivity readings are attained and/or the water is relatively free of sediment. Prior to purging and sampling, the water level in each well will be measured with an electronic water level indicator and checked for free product with a new, clean, disposable polyethylene bailer. If free product is not observed, the wells will be purged of a minimum of three well volumes of water from each well. Ground water generated from well development and purging activities will be pumped into 55-gallon drums to be stored on site. One water sample will be collected from each well using either a new polyethylene disposable bailers or submersible pump. Samples will be decanted into appropriate sampling containers provided by the analytical laboratory . The samples will immediately be placed in an ice chest containing ice. Water samples along with a travel blank will be transported under chain-of- custody documentation to a California-certified laboratory for analysis as described above. The sampling equipment will be cleaned with a solution of trisodium phosphate between each well to minimize the potential for cross-contamination. INK WALLACE•KUHL Re y&,d pa1wr &ASSOCIATES INC.