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ii Ps A Coneog a-Rovers & ssiates . STANDARD FIELD PROCEDURES FOR HAND-AUGER SOIL BORINGS This document describes Conestoga-Rovers & Associates standard field methods for drilling and sampling soil borings using a hand-auger. These procedures are designed to comply with Federal, State and local regulatory guidelines. Specific field procedures are summarized below. 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 Professional Geologist (PG) 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 grain size category, • Color, • Approximate water or product saturation percentage, • Observed odor and/or discoloration, • Other significant observations(i.e. cementation,presence of marker horizons,mineralogy),and • Estimated permeability. Soil Boring and Sampling Hand-auger borings are typically drilled using a hand-held bucket auger to remove soil to the desired sampling depth. Samples are collected using lined split-barrel or equivalent samplers driven into undisturbed sediments beyond the bottom of the augered hole. The vertical location of each soil sample is determined using a tape measure. All sample depths use the ground surface immediately adjacent to the boring as a datum: The horizontal location of each boring is measured in the field from an onsite permanent reference using a measuring wheel or tape measure. Augering and sampling equipment is steam-cleaned 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.. 1 of 2 i i