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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
James L. Conca, Michael J. Apted, Wei Zhou, Randolph C. Arthur, John H. Kessler
Nuclear Technology | Volume 124 | Number 1 | October 1998 | Pages 88-100
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT98-A2911
Articles are hosted by Taylor and Francis Online.
A flow barrier system (FBS) that includes a Richards barrier acts in an unsaturated hydrogeologic system to prevent the advective flow of water down through the barrier. Thus, an FBS placed above any solid waste material buried in the unsaturated zone could greatly aid in isolating the waste by keeping the waste away from flowing water. The FBS, consisting of a layer of highly conductive, fine-grained material overlying a sloped gravel layer, is proposed to isolate high-level radioactive waste (HLW) at a candidate disposal facility located in the unsaturated zone at Yucca Mountain in Nevada. A series of laboratory experiments were conducted to (a) assure that the FBS of a specific design can divert the anticipated maximum advective flow (under ideal conditions as well as for the case of a disturbed interface between the two layers caused by, for example, improper initial emplacement or faulting due to seismic activity), (b) investigate water imbibition into the gravel, and (c) measure the diffusion coefficient of the tuff gravel under partially saturated conditions. The main results show that (a) the FBS used in the study can divert point- source flow rates as high as 2.6 × 105 l/yr; (b) this FBS will continue performing with offsets of the interface as great as 50 cm or more; (c) after 12 months of testing, moisture penetrates the gravel only several grain diameters; and (d) the gravel effective diffusion coefficient is <10-11 cm2/s under such low partial saturations. These results indicate that a properly designed FBS can be successful at isolating the HLW under the anticipated range of environmental conditions that exist both now and in the future at Yucca Mountain.
