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Decommissioning & Environmental Sciences
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.
Lorenzo P. Pagani, George E. Apostolakis, Pavel Hejzlar
Nuclear Technology | Volume 149 | Number 2 | February 2005 | Pages 129-140
Technical Paper | Reactor Safety | doi.org/10.13182/NT149-129
Articles are hosted by Taylor and Francis Online.
Passive safety systems are commonly considered to be more reliable than active systems. The lack of mechanical moving parts or other active components drastically reduces the probabilities of hardware failure. For passive systems, it is necessary to introduce the concept of functional failure, i.e., the possibility that the loads will exceed the capacity in a reliability physics framework. In this paper we analyze the passive cooling of a gas-cooled fast reactor, and we use an importance-sampling Monte Carlo technique to propagate the epistemic uncertainties and to calculate the probabilities of functional failures. The results show that functional failures are an important contributor to the overall failure probability of the system and, therefore, should be included in probabilistic risk assessments. A comparison with an alternative active design is considered also. The results show that the active system can have, for this particular application, better reliability than the passive one.