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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
August W. Cronenberg, E. L. Tolman
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 273-282
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27654
Articles are hosted by Taylor and Francis Online.
Inspection of the Three Mile Island Unit 2 (TMI-2) reactor vessel has yielded a wealth of information on core melt debris thermal interactions with vessel internal structures. The observed damage state of such structures is summarized and an analysis is presented to further the understanding of governing physical processes. Specifically, thermal damage is assessed for the baffle plates surrounding the core periphery, the core former plates, the bottom head instrument penetrations, and the lower head. Analysis indicates that differences in damage characteristics to such structures are due largely to differences in contact time with molten corium, the heat capacity of the various structures, and exposure to coolant. Vessel and debris examinations corroborate the present understanding of melt debris/structural interactions during the melt relocation phase of the TMI-2 accident.