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s Lo in of Bonnas Soil cuttings and samples are logged using the Unified Soil Classification System Samples not selected for chemical analysis and the soil sampler shoe are extruded in the field for examination. The texture, color, moisture, plasticity, and consistency of soil, the blow counts, and subjective evidence of hydrocarbons, such as soil staining, obvious product odor, and photoionization detector (or similar instrument) readings are noted in the field on the Logs of Borings. Sampling of Drill Cutting Soil samples are collected from the stockpiled dell cuttings by driving a hand-operated percussion sampler fitted with a clean brass sleeve into the stockpiled soil. The sleeve is removed from the sampler and promptly sealed with aluminum foil, plastic caps, and duct tape. The sample is then labeled and placed in iced storage. Chain of Custody Records are initiated by the geologist and accompany the samples to the analytical laboratory. Disposal of the drill cuttings at an appropriate disposal facility is the responsibility of the client. Monitoring-Well Constriction Monitonng wells are constructed in the bonngs with thread jointed, 2-inch inner-diameter, Schedule 40 PVC casing. No chemical cements, glues, or solvents are used in well construction. The screened portion of each well consists of factory-perforated casing with • 0 020-inch-wide slots. The well screen extends from the total depth of the well to approximately 5 feet above the groundwater- surface:. -his screened interva: allows sampling at the air-water interface during seasonal and other fluctuations of the groundwater level. --be annular space Ln the well is packed with sand compatible with well slot size to approximately I to 2 feet above the slotted interval. A 3-foot thick bentonite plug is added above the sand pack to prevent the cement from entering the well pack. The remaining annulus is backfilled to grade with a bentonite cement slurry. Wells are protected with a traffic-rated, cast-aluminum utility box equipped with a PVC skirt. The box has a watertight seal to protect against surface-water infiltration and must be opened with a special wrench.. The design of this box discourages vandalism and reduces the possibility of accidental disturbance of the well. Well Development We wait a minimum of 24 hours after well installation before developing the groundwater monitoring wells to allow the grout to seal Before developing the monitoring wells, a water sample is collected for subjective analysis from near the water surface in the well with a dedicated disposable bailer. The wells are developed with a surge block and pump. Well development continues until the discharge water is clear of silt and sand Clay-size sediments derived from the screened portion of the formation cannot be entirely eliminated by well iR-081694 FLD