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Section No: 6 Page: 6 of 16 Revision No: 2.0 Date: January 15, 1994 Sampling Procedures 6.3.2 Semivolatile Organics (This includes Pesticides and Herbicides) Containers used to collect samples for the determination of semivolatile organic compounds should be soap and water washed followed by methanol (or isopropanol) rinsing. The sample containers should be of glass or Teflon and have screw-top covers with Teflon liners. In situations where Teflon is not available, samples may react with the aluminum foil, causing eventual contamination of the sample. Plastic containers or lids may NOT be used for the storage of samples due to the possibility of sample contaminat ion from the phthalate esters and other hydrocarbons within the plastic. Sample containers should be filled with care so as to prevent any portion of the collected sample coming in contact with the field persons gloves, thus causing contamination. Samples should not be collected or stored in the presence of exhaust fumes. If the sample comes in contact with the an automatic sampler run gent water through the sampler and use as a field blank. 6.3.3 Trace Metals In the determination of trace metals, containers can introduce either positive or negative _ errors in the measurement of trace metals by (a) contributing contaminants through leaching or surface desorption, and (b) depleting concentrations through adsorption. Thus the collection and treatment of the sample prior to analysis require particular attention. 6.4 Underground Storage Tank Samples 6.4.2 Soil Samples 6.4.2.1 Hydrocarbons Soil samples collected from a backhoe, the 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 in to the soil with a mallet or hammer. No headspace should be present in the cylinder once the sample is collected. When thesample is collected, each end of the cylinder should be covered with teflon tape and then capped with a polyethylene lid, taped and labeled. The sample ■ should be inunediately placed in an ice chest and kept cool at 4 C for delivery to the l laboratory. Care should be taken throughout, to avoid contamination of both the inside d outside of the cylinder and its contents. Samples should be kept cool at 4 C at the laboratory until they are analyzed. Holding times should not exceed 14 days from the time of collection. A portion of the 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 v' (properly prepared by contract laboratory consultant) with Teflon seal and screw cap should be used and maintained at 4 C until analysis. 6.4.2.2 Organic Lead T ethyl/t ethyl -lead are volatile; therefore, soil samples should be collected in cylinders and frozen as described for volatile hydrocarbons above.