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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Daniel W. Hudson, Mohammad Modarres
Nuclear Technology | Volume 197 | Number 3 | March 2017 | Pages 227-247
Technical Paper | doi.org/10.1080/00295450.2016.1273714
Articles are hosted by Taylor and Francis Online.
In 1986 the U.S. Nuclear Regulatory Commission (USNRC) implemented a safety goal policy in response to the 1979 Three Mile Island accident. This policy addresses the question, “How safe is safe enough?” by specifying quantitative health objectives (QHOs) for comparison with average individual early fatality and latent cancer fatality risk results computed from nuclear power plant (NPP) probabilistic risk assessments (PRAs). Comparisons of PRA results to the QHOs or other subsidiary numerical objectives are used to determine whether proposed regulatory actions should be rejected based on potential safety benefit relative to the level of residual risk to the public, before performing detailed cost-benefit analyses to determine whether they could be justified on their net value basis. Lessons learned from recent operational experience— including the 2011 Fukushima accident—indicate that concurrent accidents involving multiple units at a shared site can occur with non-negligible frequency. Yet, risk contributions from such scenarios are excluded by policy from safety goal evaluations for the nearly 60% of the U.S. NPP sites that include multiple units. The objectives of this paper are to (1) present an approach for estimating multiple unit risk metrics for comparison with the safety goal QHOs using accident scenarios from the State-of-the-Art Reactor Consequence Analyses (SOARCA) Project; and (2) using this approach, evaluate the effects of including risk contributions from concurrent multiunit accidents in safety goal evaluations. The approach is demonstrated using a two-unit case study involving two representative NPP sites that are each comprised of two co-located operating reactor units. This paper (1) summarizes results and insights obtained from the two-unit case study; (2) describes additional considerations for applying methods to sites comprised of two or more units, including other major radiological sources; and (3) identifies potential areas for further research.