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1 by the analytic laboratory Samples are labeled, placed in protective foam sleeves, stored on crushed ice at or below 4° C, and transported under cham-of-custody to the laboratory After the CPT probes are removed, the borings are filled to the ground surface with cement grout poured or pumped through a tremie pipe Objectives Soil samples are collected to characterize subsurface lithology, assess whether the soils exhibit obvious hydrocarbon or other compound vapor odor or staining,estimate ground water depth and quality and to submit samples for chemical analysis Soil Classification/Logging All soil samples are classified according to the Unified Soil Classification System by a trained geologist or engineer working under the supervision of a California Registered Geologist(RG) or a Certified Engineering Geologist(CEG) The following soil properties are noted for each soil sample • Principal and secondary grain size category (i e , sand, silt, clay or gravel) • Approximate percentage of each gram size category, • Color, • Approximate water or separate-phase hydrocarbon saturation percentage, • Observed odor and/or discoloration, • Other significant observations(i e , cementation, presence of marker horizons, mineralogy), and • Estimated permeability Soil Sampling Soil samples are collected from bonngs driven using hydraulic push technologies A minimum of one and one half ft of the soil column is collected for every five ft of drilled depth Additional soil samples can be collected near the water table and at lithologic changes Samples are collected using samplers lined with polyethylene or brass tubes driven into undisturbed sediments at the bottom of the borehole The ground surface immediately adjacent to the boring is used as a datum to measure sample depth The horizontal location of each boring is measured in the field relative to a permanent on-site reference using a measuring wheel or tape measure Drilling and sampling equipment is steam-cleaned or washed prior to drilling and between borings to prevent cross-contamination Sampling equipment is washed between samples with trisodium phosphate or an equivalent EPA-approved detergent Sample Storage, Handling and Transport Sampling tubes chosen for analysis are trimmed of excess soil and capped with Teflon tape and plastic end caps Soil samples are labeled and stored at or below 4°C on either crushed or dry ice, depending upon local regulations Samples are transported under chain-of-custody to a State-certified analytic laboratory Field Screening