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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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.
Rob P. Rechard
Nuclear Technology | Volume 190 | Number 2 | May 2015 | Pages 127-160
Technical Paper | Reactor Safety | doi.org/10.13182/NT14-41
Articles are hosted by Taylor and Francis Online.
This paper, Part II of two companion papers, demonstrates the concepts for evaluating the criticality scenario class after closure of a geologic repository for spent nuclear fuel (SNF) and high-level radioactive waste. As an example, the low-probability rationale used to exclude consideration of criticality in the performance assessment of the potential Yucca Mountain (YM) repository in southern Nevada is summarized. The Yucca Mountain Project (YMP) presented a quantitative rationale that the probability of criticality inside breached waste containers was <10−4 over 104 yr to show that criticality was not necessary to consider. The dominant probability occurred when neutron absorber material was inadvertently left out for a package disposing of SNF from experimental reactors owned by the U.S. Department of Energy. In addition, this paper develops a quantitative estimate of the low probability of criticality outside the package in either the engineered or geologic barrier to complement the qualitative rationale developed by YMP. Because consequence may also be used as the basis of screening, consequences of criticality at the potential YM repository are roughly estimated, based on results from the literature. The consequences are then combined with the low-probability estimates as a complementary cumulative distribution function to place the corresponding estimated consequences in context and, thereby, provide further perspective on excluding the criticality scenario class.
