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ameO <br /> groundwater. Proposed sampling locations are shown on Figures 3 through 6; an overview of <br /> proposed sampling locations is shown on Figure 7. <br /> 4.0 FIELD AND ANALYTICAL METHODS <br /> Prior to drilling, Underground Service Alert (USA)will be notified, the soil boring locations will <br /> be cleared by a private underground utility locator, and appropriate permits will be obtained <br /> from the San Joaquin County Public Health Services, Environmental Health Division. Access <br /> to drill in the City of Tracy streets will be obtained from the City of Tracy (via encroachment <br /> permits) and access to drill on the Rail Yard property will be obtained from UPRR. AMEC will <br /> prepare a site-specific health and safety plan that will include job loss analyses for all major <br /> work processes to be conducted during field activities. <br /> Soil and groundwater sampling methods, analytical methods, quality assurance/quality control <br /> procedures, and borehole destruction and surveying procedures are described below. <br /> 4.1 SOIL AND GROUNDWATER SAMPLING METHODS <br /> To meet the project objective, AMEC proposes to advance 10 borings for the collection of soil <br /> and groundwater samples. Each boring will be hand augered to a depth of 8 feet bgs to clear <br /> for utilities, then advanced using a hydraulically driven core barrel and drive sampler to the <br /> total depth of the boring. A continuous core of the soil will be collected and examined from <br /> each soil boring location, and the lithology will be logged by an AMEC field geologist or <br /> scientist under the supervision of a California Professional Geologist. Soil lithology will be <br /> logged using the visual-manual procedures of American Society for Testing and Materials <br /> (ASTM) Standard D 2488 for guidance, which is based on the Unified Soil Classification <br /> System, as described in ASTM D 2488-06. In addition, organic vapor meter(OVM) readings <br /> will be taken and recorded at various depths. Borings will be advanced to a depth of <br /> approximately 25 feet bgs based on the previously observed depth to groundwater(11 to <br /> 21 feet bgs) and the depth of affected soil (generally observed between 15 to 20 feet bgs in <br /> previous borings on the Tracy Rail Yard site). If impacted soil is encountered, borings will be <br /> advanced to 25 feet bgs or until no evidence of petroleum hydrocarbons is observed in the soil <br /> core, whichever is deeper. <br /> AMEC will collect two soil samples from each boring within the upper 10 feet to obtain data for <br /> possible use in a health risk assessment(HRA). AMEC will also collect soil samples from <br /> depths corresponding to the depth where affected soil was encountered at the Tracy Rail Yard <br /> (approximately 15 to 20 feet bgs). If affected soil is observed in a soil boring, samples of <br /> affected soil will be targeted. Two soil samples also will be collected below visibly-affected soil, <br /> with the deeper sample put on hold pending analysis of the shallower sample collected below <br /> AMEC Geomatrix, Inc. <br /> X:\16000s\161140\4000 REG ULATORY\South WP 063011\1 txt,cvrs,Itrs\Text.docx 5 <br />