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DER <br /> A-2.3 <br /> u9nvrovk.rtromx�wonz <br /> A-2.3 Collection of Soil Samples <br /> Soil samples are collected approximately every 5 feet for field screening, lithologic <br /> logging, and potential chemical analysis. Samples are collected by advancing the <br /> boring to a point immediately above the desired sampling depth and then driving <br /> (vertical borings) or pushing (slant borings) a Modified California Sampler, lined with <br /> three brass tubes, into the undisturbed soil. The sampler is then removed from the <br /> ' bottom of the boring. The ends of the bottom (third) tube are covered with Teflon and <br /> sealed with tight-fitting plastic caps. <br /> 1 After the samples are collected they are individually labeled. The label includes <br /> Kleinfelder's name, job number, the date and time the sample was collected, the <br /> employee number of the individual who performed the sampling, and a unique five-digit <br /> sample identification number. A custody seal is also placed on the sample in such a <br /> ' way that any attempt to tamper with the sample is easily visible. An example of a <br /> sample label and custody seal are attached at the end of this appendix. <br /> A-2.4 Qualitative Field Screening <br /> An organic vapor detector, such as a Photovac TIP, using a photoionization detector <br /> (PID) or a Foxboro flame ionization detector (FID), is used to provide a qualitative <br /> screening of each soil sample collected from the borings. The organic vapor detector <br /> measures ionizable compounds in the air in parts per million by volume (ppmv). Field <br /> calibration is performed using a calibrated span gas. Ambient air is used to set the <br /> instrument zero. A calibration form is attached. The soil contained in the cone of the <br /> sampler or in a brass tube is exposed and screened with the organic vapor detector. <br /> The vapor reading is noted as the field screening result. <br /> For the protection of the drilling crew, the organic vapor detector is also used to <br /> ' measure the volatile concentrations in the breathing zone prior to and during the drilling <br /> of the samples. Total ionizable hydrocarbon readings in excess of one ppmv may <br /> necessitate respiratory protection for the affected crew members. This requirement is <br /> 1 included in the complete field health and safety plan developed for the project prior to <br /> the start of field work. <br /> 101486.4/STO11 R242 Page A-2 October 31, 2011 <br /> Copyright 2011 Kleinfelder <br />