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L Now The soil in the remaining tubes will be examined in the field for observable signs of petroleum hydrocarbons, screened for hydrocarbon vapors using a photo ionization detector, and examined for soil classification. Soil will be classified in general accordance with the Unified Soil Classification System. The soil classification and description, including blow counts, grain size, size grading, subordinate constituents, color, density, moisture content, and organic vapor readings, will be recorded on a field boring/well log. F Soil cuttings generated during the work activities will be placed in 55-gallon drums for later . disposal. Soil samples collected for chemical analyses will be delivered to a California state certified analytical laboratory. Soil samples will be analyzed for total petroleum hydrocarbons as gasoline W (TPH-G) using EPA Method 8015M; and for benzene, toluene, ethylbenzene, total xylenes (BTEX), methyl tertiary butyl ether (MTBE), diisopropyl ether (DIPE), tertiary-butyl alcohol (TBA), ethyl tertiary-butyl ether (ETBE), and tertiary-amyl methyl ether (TAME) using EPA Method 8260B. Grab Groundwater Sampling At the desired sampling depth, grab groundwater samples will be collected from the bottom of each Geoprobe boring using a temporary PVC well casing and a sample bailer. A screened PVC well casing will be placed within the open Geoprobe borehole after the drive rods have been removed. After sufficient water has entered the well casing, a small-diameter, PVC bailer with a bottom check-valve will be lowered into the well casing using a nylon cord. Once the bailer has been retrieved, the water from the bailer will be gently decanted into 40-ml, glass sample vials. The groundwater samples will be stored on ice prior to delivery to an independent, state-certified laboratory for analysis of TPH-G using EPA Method 8015M, and BTEX, MTBE, DIPE, TBA, ETBE, and TAME using EPA Method 8020B. Decontamination Procedures To avoid crass-contamination, the sampler and other reusable equipment will be broken down after each sample and cleaned, along with sample tubes, using an approved non-phosphate detergent. The sampler and sample tubes will be double-rinsed in distilled water, and allowed to air dry. Geoprobe rods and other drilling equipment will be steam-cleaned or replaced with �- clean equipment between boreholes. Monitoring Well Installation and Development Procedures Well Installation L At the completion of drilling and sampling, Monitoring Wells MW-1 through MW-5 will be completed as groundwater monitoring wells. The well will be constructed of clean, 2-inch- t,,, diameter, Schedule 40, threaded PVC. Screened casing with factory-milled 0.02-inch slots will be installed from approximately 15 to 35 feet below ground surface (bgs) in the center of the t.