REV. #: 0.0 TANK SAMPLING 1.0 SCOPE AND APPLICATION

The purpose of this standard operating procedure (SOP) is to provide technical guidance for the implementation of sampling protocols for tanks and other confined spaces from outside the vessel. These are standard (i.e., typically applicable) operating procedures which may be varied or changed as required, dependent on site conditions, equipment limitations or limitations imposed by the procedure or other procedure limitations. In all instances, the ultimate procedures employed should be documented and associated with the final report. Mention of trade names or commercial products does not constitute U.S. EPA endorsement or recommendation for use. 2.0 METHOD SUMMARY The safe collection of a representative sample should be the criteria for selecting sample locations. A representative sample can be collected using techniques or equipment that are designed for obtaining liquids or sludges from various depths. The structure and characteristics of storage tanks present problems with collection of samples from more than one location; therefore, the selection of sampling devices is an important consideration. Depending on the type of vessel and characteristics of the material to be sampled, one can choose a bacon bomb sampler, sludge judge, subsurface grab sampler, glass thief, bailer or Composite Liquid Waste Sampler (COLIWASA) to collect the sample. A sludge judge, bacon bomb or COLIWASA can be used to determine if the tank contents are stratified. Various other custom-made samplers may be used depending on the specific application. All sample locations should be surveyed for air quality prior to sampling. At no time should sampling continue with an LEL reading greater than 25%