REMOVAL_1991 - Laserfiche WebLink

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APPENDIX C SAMPLE COLLECTION, TRANSPORT, AND LABORATORY ANALYSES A. Sample Collection 1. Field Notebook The field investigator should keep a field notebook (preferably bound with pages numbered) to record sample collection proce- dures, dates, laboratory identification, sample collection location, and the name of the sampler. This is important for later recall or legal challenge. 2. Soil Samples a. Hydrocarbons: Soil samples collected from a backhoe, the 1 ground or a soil coring device, should be collected in a thin-walled stainless steel or brass cylinder at least three inches long by one inch in diameter that has been prepared by' the laboratory doing the analysis or the project consultant (cylinders can be made to fit inside the preferred split-barrel core sampler) . About one inch of soil should be removed from the immediate surface area where the sample is to be taken and the cylinder then pounded into the soil with a wooden mallet. No headspace should be present in the cylinder once the sample is collected. When the sample is collected, each end of the cylinder should be covered with aluminum foil and then capped with a polyethylene lid, taped, and labeled. The sample should then be immediately placed in an ice chest containing dry ice and kept frozen for delivery to the laboratory. Care should be taken throughout to avoid contamination of both the inside and outside of the cylinder and its contents (1) . Samples should be kept frozen at the laboratory until they are analyzed. Holding time should not exceed 14 days from the time of collection. Frozen soil cores should be removed from the cylinders by spot heating the cylinder and immedi- ately extruding the sample (or a portion of it) . A portion of the frozen sample should be removed and prepared for analysis according to approved EPA methods. In situations where the above procedure is inappropriate, i.e. semi-solid samples, glass vials (properly prepared by contract laboratory or consultant) with Teflon seal and screw cap should be used, and maintained at 40C until analysis. -60-