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flight hollow stem augers. Prior to drilling each well boring, the augers were cleaned and decontaminated by the use of steam. The borings were drilled to depths ranging between 8 and 18 feet below the ground surface, and soil samples were collected at 4-foot intervals within the unsaturated zone. Soil samples were collected ' during drilling utilizing a modified California split-spoon sampler equipped with precleaned brass sampling tubes. The sampler was cleaned prior to each use in an Alconox-O solution and rinsed with ' deionized water. Soil samples were retained in brass tubes by covering the ends of the tubes with Teflon® film and plastic caps During drilling, soil samples were labelled with a unique sample number, the project name and location, the date and time, and the sampler's initials. Sample identification numbers reference the boring number and the sample depth from the ground surface Samples were then placed in Zip-Lock® type plastic bags, sealed, and placed in an iced cooler. Information noted on the label was recorded on a chain-of-custody form After completion of drilling, the samples ' were delivered under chain-of-custody to Anametrix, Inc., a C aliforma-certified laboratory Soil samples and drill cuttings were visually inspected and classified according to the Unified Soil Classification System (USCS) by a qualified ERM-West geologist. Boring logs were constructed to record vertical variations in lithology, moisture content, color, and texture of the soil. Appendix P contains the drilling logs for the Phase II investigation. All soil removed from the boreholes and all rinsate generated was stored in sealed 55-gallon drums pending the results of laboratory analyses. Each drum was clearly labelled to indicate its contents and boring number. The drums were stored on pallets on the loading dock MoW' A well completion form for MW-5A is also provided in Appendix P MW-5A was onstructed using and screen 4-inch- diameter diameter Schedule 40 PVC flush-threadcasing ' well was constructed with 4-inch casing and screen so that, if necessary, it could be used as an extraction well for ground water remediation. The well screen has a slot size of 0 02 inches with a screened interval length of 10 feet. The bottom of the screen is closed with a Schedule 40 PVC flush-threaded plug. The top of the well is capped with a I lockable,lementnallble plastic casiing materials were cleaned lug and covered and slip cap. Prior to p decontaminated by the use of steam. ' The annular space between the borehole wall and well screen was backfilled with clean ne Star he job site equivalent) 2/16 mesh s and The sand was supplied in sealed paper sacks. The sand 5-10