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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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.
Thomas A. Buscheck, John J. Nitao
Nuclear Technology | Volume 104 | Number 3 | December 1993 | Pages 418-448
Technical Paper | Special Issue on Waste Management / Radioactive Waste Management | doi.org/10.13182/NT93-A34901
Articles are hosted by Taylor and Francis Online.
To safely and permanently store high-level nuclear waste, the potential Yucca Mountain repository site must mitigate the release and transport of radionuclides for tens of thousands of years. In the failure scenario of greatest concern, water would contact a waste package, accelerate its failure rate, and eventually transport radionuclides to the water table. Analyses have demonstrated that (a) the ambient hydrological system will be dominated by repository-heat-driven hydrothermal flow for tens of thousands of years and (b) the only significant source of liquid water is from nonequilibrium fracture flow, driven either by meteoric sources or by the condensation of repository-heat-driven flow of water vapor. For sub-boiling conditions, the infiltration of meteoric water and condensate drainage are controlled by the highly heterogeneous distribution of hydrological properties, while for above-boiling conditions, they are largely determined thermodynamically. In a concept called the “extended-dry repository,” the heat of radioactive decay generates a region of above-boiling temperatures around the repository, thereby extending the time before liquid water can contact a waste package. It is also found that the magnitude of repository-heat-driven, buoyant, liquid-phase convection in the saturated zone is more dependent on the total mass of emplaced spent nuclear fuel (SNF) than on the details of SNF emplacement, such as the areal power density (expressed in kilowatts per acre) or SNF age.