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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.
T. Sampat Sridhar, Ahmad G. Solomah
Nuclear Technology | Volume 85 | Number 1 | April 1989 | Pages 89-97
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT89-A34230
Articles are hosted by Taylor and Francis Online.
A process has been developed to immobilize the uranium-rich high-level radioactive waste generated from the reprocessing of CANDU spent fuel using the amine process. The calcination technology developed in the Process Development Section at the Whiteshell Nuclear Research Establishment has been used to demonstrate this process. Simulated liquid waste and SYN-ROC additives were denitrated thermochemically in a continuous operation using the Whiteshell Roto-Spray Calciner. Technically dense (≥95% theoretical density) samples of SYNROC-FA crystalline ceramic waste form containing ∼50 wt% simulated amine process waste were prepared by pressureless sintering at 1250°C under reducing atmosphere (N2-5 vol% H2) conditions. X-ray diffraction and grain microanalyses using an electron probe microanalyzer and an energy dispersive X-ray analyzer revealed the existence of a pyrochlore-structured phase CaU(Ti3+, Ti4+)2O7, perovskite (Ca,U)(Ti3+,Ti4+)O3, barium-hollandite Ba1.14(Al3+, Ti3+)2.27Ti5.71O16, and uraninite (U,Ca,Ti)O2. Leach tests (modified MCC-1) carried out in a simulated Canadian shield groundwater at 90°C for 120 days revealed that barium was the only ion released into the leachants, with an initial leach rate of 2x 10-1 g · m-2. day-1 measured after a 3-day period. The leach rate dropped to 6 x 10-3 g.m-2.day-1 after 120 days of leaching. The concentrations of uranium and other simulated fission products in the leachants were below the detection limits of inductively coupled plasma spectrometry and atomic absorption techniques. The leach rates of uranium and titanium were estimated to be <6 x 10-5 and 3 x 10-5 g·m-2.day-1, respectively.
