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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.
Simcha Stroes-Gascoyne, Lawrence H. Johnson, Dennis M. Sellinger
Nuclear Technology | Volume 77 | Number 3 | June 1987 | Pages 320-330
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT87-A33972
Articles are hosted by Taylor and Francis Online.
Safety assessment of the used fuel disposal concept requires a study of the integrity of used fuel in contact with groundwater. In this context, the initial release of 137Cs and I29I from used Canada deuterium uranium fuel segments, exposed to water at 25°C, has been studied as a function of fuel irradiation history. Percentages of inventories released after 5 days of leaching are compared to stable xenon fuel-sheath gap inventories. Cesium-137/xenon and 129I/xenon release ratios average ∼0.2 for low linear power rating (LLPR) fuel. For high linear power rating fuel, ratios are considerably larger and may approach 1. For LLPR fuel, the ratios become larger when the leaching time is increased. It is proposed that these differences are related to the microstructure of used fuel. The results indicate that the source term for the instantaneous release of isotopes of cesium and iodine should include all of the fuel-sheath gap inventory. Power history data and calculated gas release data can be used to accurately estimate the contribution of the fuel-sheath gap inventory to the source term for radionuclide release.
