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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Richard R. Hobbins, Malcolm L. Russell, Charles S. Olsen, Richard K. McCardell
Nuclear Technology | Volume 87 | Number 4 | December 1989 | Pages 1005-1012
Late Paper | TMI-2: Decontamination and Waste Management / Nuclear Safety | doi.org/10.13182/NT89-A27692
Articles are hosted by Taylor and Francis Online.
The behavior of melts in severe accident sequences affects the nature (composition and fission product inventory) of the debris released from the vessel upon lower head failure in unmitigated accidents and the coolability of debris at various stages in managed accidents. Core melting progressed further in the Three Mile Island Unit 2 (TMI-2) accident than in any of the severe core damage experiments that have been conducted since the accident, and, therefore, TMI-2 represents a valuable source of information that extends into later phases of core melt progression, including melt relocation into the lower plenum. Examination and evaluation of melts within the TMI-2 reactor vessel indicate that melts can form uncoolable geometries in the core but they can also break through the surrounding crust, massively relocate into the lower plenum, and fragment upon interaction with water resident in the lower plenum to form a rubble bed of coolable geometry. The chemistry of melts, particularly the oxygen potential, affects fission product chemical form and, therefore, retention in the melt. The chemistry also determines interactions of the melts with reactor pressure vessel components.