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[en] The current management system in the United States for commercial spent nuclear fuel does not emphasize integration among storage, transportation, and disposal. The large containers in use for dry-storage remain at high temperatures for decades and, thereby, delay removal from decommissioned reactors. The large containers also have no easy path to disposal unless (1) disposal is delayed (up to 150 years for some geologic media); (2) the contents are repackaged into smaller, cooler packages; or (3) the high temperatures are used as de facto site-selection criteria for a repository. Implementing consolidated interim storage could address many issues that exist because of this lack of integration. A consolidated interim storage facility that includes appropriate capabilities acts as a universal coupler that allows existing disparate parts to integrate as a system. Previous agencies and commissions have noted this theme before as a way to provide flexibility in the waste management system. This rationale is elaborated upon here. (author)
[en] The quality of systems constructed from components that have been produced at enterprises in different locations is considered. A particular sequence of processes is required in order to improve the performance of enterprises involved in the design and production of such systems. That sequence is identified. The basic principles that ensure the quality of such systems are formulated: in particular, compatibility of the components is essential. The constraints associated with the system’s emergent properties must be taken into account.
[en] The latest version of the University of Toronto Glacial Systems Model (UofTGSM) was employed in the development of data sets describing the evolution of surface boundary conditions above a potential spent fuel repository over the course of a 122.5 kyr cycle of glaciation. The new data sets build increased confidence upon the previous UofTGSM generated data sets that Peltier (2006) supplied for this purpose. The components of the UofTGSM have been updated to a framework reflecting the current state-of-the-art, and a new strategy has been adopted to preserve consistency with observations independently of detailed assumptions about ice-sheet dynamics. A mass-balance adjustment is employed to nudge the ice-thickness solution towards the observationally well-validated ICE-6GC reconstruction, and dynamical variability can be analyzed in the context of ensembles with different exponential relaxation time-scales. This approach is used to diagnose ice thickness, permafrost thickness, basal temperature, meltwater production, lake depth, and other two dimensional, time-varying fields from a reference solution along with corresponding local error estimates. Beyond reflecting significant numerical advances that enabled the new UofTGSM to better represent basal processes, ice-shelves, temperate ice-water mixtures and other physics, the new results benefit from the many new measurements that constrained ICE-6GC (and therefore, indirectly, the nudged paleoclimate simulations). Nudging offers a more practical approach to leading-order data assimilation and error estimation than Bayesian calibration, which was employed in Peltier (2006), and which will continue to be of use in more detailed explorations of observationally constrained model parameter spaces. Rather than consisting of discrete time-series at the sites of hypothetical spent-fuel repositories, the new dataset also includes time-varying two-dimensional geographic distributions covering all of Canada. (author)
[en] This Quality Assurance Plan (QAP) provides the overall Quality Assurance (QA) program requirements, technical planning, and general quality practices to be applied to the U.S. Department of Energy (DOE) Environmental Management (EM) Nevada Program Soils Activity. The QAP requirements are consistent with the Quality Systems for Environmental Data and Technology Programs–Requirements with Guidance for Use (ANSI/ASQ, 2004); the Intergovernmental Data Quality Task Force Uniform Federal Policy for Quality Assurance Project Plans (IDQTF, 2005); and 10 Code of Federal Regulations (CFR) 830.120, Quality Assurance (CFR, 2017a), which apply to specific activities performed under the Soils Activity. The EM Nevada Program owns and is responsible for maintaining this QAP. Individual participants are responsible for implementing the requirements of this QAP in accordance with their own approved programs, processes, plans, and procedures. If a participant’s requirement document differs from this QAP, the stricter requirement will take precedence.
[en] This document is realized in the framework of the axis 3 of the law of 1991 on the radioactive wastes management. It presents a long time subsurface storage installation of medium activity long life wastes. The long time of the installation would reach 300 years at the maximum. The feasibility is demonstrated and the design choices are presented and justified. The specific points of the long time storage installation, which are different from a classical industrial storage installation, are also discussed. (A.L.B.)
[fr]Ce rapport thematique s'inscrit dans le cadre de l'axe 3 de la loi du 30 decembre 1991 destine a apporter des elements de reponse sur les procedes de conditionnement et d'entreposage de longue duree des dechets radioactifs a vie longue. Il presente une installation d'entreposage de longue duree de dechets MA-VL (Moyenne Activite a Vie Longue) concept en subsurface. La notion de longue duree est appreciee par rapport a la duree habituelle d'exploitation d'une INB, c'est a dire de l'ordre de 50 ans. La longue duree est comprise comme seculaire : la duree de vie de l'installation retenue pour la conception pourra atteindre 300 ans au maximum. La faisabilite d'entrepots concus specifiquement pour la longue duree est demontree. Les choix qui ont conduit a la conception de l'entrepot sont presentes et justifies dans ce rapport. Les points particuliers a l'installation d'entreposage de longue duree qui la distingue d'une installation d'entreposage industrielle classique sont resumes ci apres. (auteurs)
[en] In this paper, a review of radioactive wastes treatment using thermal plasma technology is presented as a treatment method for radioactive waste management. Virtually all waste streams can be treated by the thermal plasma technologies, resulting in a conditioned product, free from organics and liquids, definitely meeting the acceptance criteria for safe storage and disposal. The application of the thermal plasma system in the nuclear area is still one of the current research topics due to the theoretical and practical complexity of the treatment. This paper discusses the performance of the thermal plasma systems, addressing the advantages and limitations of the method. (author)
[en] In 2019 the LHCb RICH detector will be upgraded to increase the read out rate from 1 MHz to 40 MHz. As a consequence, the current Hybrid Photon Detectors will have to be replaced. Multi-anode Photomultiplier Tubes (MaPMTs) from Hamamatsu with 64-channels will be used: the 1-in. R13742 and the 2-in. R13743 MaPMTs (custom modifications of the MaPMTs R11625 and R12699). Quality assurance testing of these MaPMTs using custom-developed readout electronics has started. We present the design and realisation of the test facilities to ensure consistency in testing and validation. A total of 3100 units of the R13742 and 450 units of the R13743 will be tested requiring high efficiency and reliability from the test stations. We report on the test programme and protocols, characterising the units and assuring compliance with specifications. First results of testing and detector characterisation will be presented, based on the pre-series production, comprising 54 units of R13742 and 20 units of R13743.
[en] Reliable methods for estimating the cost of a radioactive waste disposal programme are crucial to ensure that the necessary funding for completing the disposal programme is available. Estimating the cost for disposal is however a challenging and complex task. Disposal programmes themselves are complex and long-term undertakings and conditions can be expected to change significantly over the time-span during which a disposal programme is developed and implemented. This publication provides Member States with guidance on how to develop cost estimates for a disposal programme and on how to establish funding mechanisms. It will help readers in becoming informed clients by familiarizing themselves with the approaches and complexities in cost estimates and funding mechanisms for disposal. The publication is applicable to all waste categories and both near surface and geological disposal. It contains relevant examples and case studies from national programmes. The cost figures are intended to give an indication of the possible cost of certain parts or aspects of the disposal programme rather than to compare different disposal programmes’ costs.
[en] Dismantling, clean-up, decontamination and radioactive waste managing are the components of a mature and growing nuclear decommissioning market in France. It is known that these activities do not require as much staff as a nuclear facility in operation but some related projects like the recycling of very low level radioactive wastes or the implementation of smart grids can create jobs locally. A feature of the nuclear industry is that it is spread all across the country and the response in terms of jobs to the definitive closure of a facility should be found locally so that the local economic tissue is preserved. For instance in the region where the Fessenheim nuclear power plant is about to shutdown definitely, an industrial tissue is being developed. Another example is the CIGEO facility that is being built with the aim of disposing high level radioactive waste in deep geological layers. A nearby industrial activity zone has been created where local enterprises have moved in in order to favor synergy and industrial development. (A.C.)
[en] The project was to improve the standards of radiation protection at Andreeva Bay, a former Navy base. The project involves establishing the Radiological Management System for the site. This will include the provision of appropriate radiological protection equipment to ensure that the Radiological Management System can be implemented. A number of other related sub-tasks are included to help provide a fully integrated system at the site.