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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.
David A. Petti, James P. Adams, James L. Anderson, Richard R. Hobbins
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 243-263
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27652
Articles are hosted by Taylor and Francis Online.
An analysis of fission product release during the Three Mile Island Unit 2 (TMI-2) accident has been performed to provide an understanding of fission product behavior that is consistent with both the best-estimate accident scenario and fission product results from the sample acquisition and examination efforts. “Firstprinciples” fission product release models are used to describe release from intact, disrupted, and molten fuel during the various phases of the TMI-2 accident. Extensive gaseous and volatile fission product release is calculated to have occurred, with local regions of the core experiencing up to 100% release. Diffusion is calculated to have dominated release during the initial core heatup, while bubble coalescence and rise dominated release from the large consolidated region of molten material. The calculations are generally consistent with fission product retention data from upper and lower plenum debris bed samples. An exception to this is the small retention of cesium in the lower plenum samples, suggesting that cesium may have been in a low-volatile chemical form. The small release fractions measured for the less volatile fission product oxides (SrO, Eu2O3, and Ce2O3) are calculated to have resulted from the low partial pressures of these species in the melt coupled with the low surface-to-volume ratio of the consolidated melt region. Metallic species (ruthenium and antimony) are thought to be associated with metallic core structural material debris.
