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Samples were collected at five foot intervals from the ground surface to total depth of the wells through use of a California modified split spoon sampler equipped with laboratory-cleaned brass sleeves. Samples were collected by advancing the boring to a point immediately above the sampling depth, then driving the sampler into the native soil through the hollow center of the auger. The sampler was then driven 18 inches or to refusal with a standard 140 pound hammer dropped 30 inches. Refusal was defined, in this case, as greater than 50 blows for six inches. The number of blows required to drive the sampler each successive six inches was counted and recorded to give an indication of soil consistency. Boring Logs for boring B-4 are presented in Plates P-3 and Plate P-4. Soil samples collected for possible chemical analyses were immediately sealed with aluminum foil, plastic caps, and air- tight tape. They were then labeled and placed in iced storage for transport to the analytical laboratory. Drill cuttings were placed in four appropriately lined D.O.T. 17H 55-gallon capacity drums, which were sealed and left on site. These drums remain the responsibility of Beacon Oil Company. Applied GeoSystems can, with the authorization of Beacon Oil Company, arrange for the transport and disposal of the soil. MW-4 was constructed with two-inch inner diameter schedule 40 threaded PVC casing. No chemical cements or solvents were used in well construction. The screened portion of the well consists of thirty feet of 0 . 020-inch machine-slotted PVC screen. The base of the well was capped with a threaded PVC plug. The well screen extends from total depth of the well to ten feet above the upper zone of saturation, allowing for seasonal fluctuation of ground water. The annular space was packed with sorted sand to approximately four feet above the perforations. A one foot thick bentonite plug was placed above the sand to prevent cement from entering the sand pack. The remaining annulus was backfilled with neat cement to grade. Details of construction of the well are graphically illustrated on the Boring Logs. A CNI utility box was placed over the well head and cemented into place flush with the surrounding station pad. The utility box has a water tight seal to protect against surface water infiltration and require a specially designed spanner wrench to open. This design reduces the possibility of well vandalism or accidental disturbance. AA01100' GeoSystems