[en] The Oak Ridge National Laboratory (ORNL) and the Savannah River Technology Center (SRTC) are involved in a demonstration project funded by the DOE's EM-50 organization. ORNL will remove radioactive cesium from approximately 25,000 gallons of supernate from the Melton Valley Storage Tanks using an ion-exchange sorbent. This loaded sorbent will then be transported to SRTC where it will be vitrified within SRTC's shielded cells facility. ORNL and SRTC are in the process of implementing a Nevada Test Site (NTS) Waste Certification Program to ensure the vitrified product meets the requirements of NVO-325. Upon DOE/NV approval, the vitrified waste is anticipated to be sent to the NTS for disposal in the June-July 1997 time frame. The Nevada Test Site Defense Waste Acceptance Criteria, Certification, and Transfer Requirements, NVO-325, Revision 1, June 1992, stipulates that the final waste forms to be shipped to the NTS comply with RCRA regulations, with compliance supported by the Toxicity Characteristic Leaching Procedure (TCLP). However, for vitrified waste forms, the TCLP is not the most appropriate leach test. SRTC developed a more appropriate leaching test for glass waste forms, the Product Consistency Test (PCT), which was recently been approved as an ASTM procedure (Attachment 1). The PCT is used to determine whether glass produced in the Defense Waste Processing Facility at the Savannah River Site meets the Waste Acceptance Product Specifications for High Level Waste (HLW). The EPA has implicitly accepted the PCT as part of the HLW Best Demonstrated Available Technology (BDAT). The PCT creates leaching conditions which are more aggressive than those for the TCLP to provide information about glass durability under accelerated (worst case) leaching conditions. In addition, the PCT is a better indicator of glass durability because it is a glass-dominated rather than a solution-dominated durability test. (Abstract Truncated)