The U.S. EPA has recently promulgated the use of a leaching procedure (TCLP) to be used as a criterion for disposal of hazardous wastes under the Land Disposal Restrictions Rule. The TCLP has also been included in the proposed rule for Identification and Listing of Hazardous Wastes.

Summarized are results of eight different studies designed to evaluate the TCLP method. Study results indicate that the TCLP procedure can be applied consistently by a diverse group of laboratories.