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Baden, Switzerland

Goto J.,NUMO | Kawamura H.,Obayashi Corporation | Chapman N.,MCM Consulting
Proceedings of the International Conference on Radioactive Waste Management and Environmental Remediation, ICEM | Year: 2013

This paper describes the development of a probabilistic methodology for the evaluation of tectonic hazards to geological repositories in Japan. The approach is a development of NUMO's ITM methodology, which produced probabilistic hazard maps for volcanism and rock deformation for periods up to about 100,000 years in a set of Case Studies that covered a large area of the country. To address potential regulatory requirements, the TOPAZ project has extended the ITM methodology to look into the period between 100,000 and 1 million years, where significant uncertainties begin to emerge about the tectonic framework within which quantitative forecasting can be made. Part of this methodology extension has been to adopt expert elicitation techniques to capture differing expert views as a means of addressing such uncertainties. This paper briefly outlines progress in this development work to date. Copyright © 2013 by ASME. Source

Chapman N.,MCM Consulting | Berryman K.,Institute of Geological & Nuclear Sciences | Villamor P.,Institute of Geological & Nuclear Sciences | Epstein W.,Lloyds Register | And 2 more authors.
Eos | Year: 2014

The destruction of the Fukushima Daiichi Nuclear Power Plant (NPP) following the March 2011 Tohoku earthquake and tsunami brought into sharp focus the susceptibility of NPPs to natural hazards. This is not a new issue - seismic hazard has affected the development of plants in the United States, and volcanic hazard was among the reasons for not commissioning the Bataan NPP in the Philippines [Connor et al., 2009]. © 2014. American Geophysical Union. All Rights Reserved. Source

Alexander W.R.,Bedrock Geosciences | Reijonen H.M.,Saanio Riekkola Oy | McKinley I.G.,MCM Consulting
Swiss Journal of Geosciences | Year: 2015

The geological disposal of radioactive wastes is generally accepted to be the most practicable approach to handling the waste inventory built up from over 70 years accumulation of power production, research–medical–industrial and military wastes. Here, a brief overview of the approach to geological disposal is presented along with some information on repository design and the assessment of repository post-closure safety. One of the significant challenges for repository safety assessment is how to extrapolate the likely long-term (i.e. ten thousand to a million years) behaviour of the repository from the necessarily short term data from analytical laboratories and underground rock laboratories currently available. One approach, common to all fields of the geosciences, but also in such diverse fields as philosophy, biology, linguistics, law etc., is to utilise the analogue argumentation methodology. For the specific case of radioactive waste management, the term ‘natural analogue’ has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment. This approach is discussed here with a brief overview of how the study of natural (and, in particular, geological) systems can provide supporting information on the likely long-term evolution of a deep geological waste repository. The overall approach is discussed and some relevant examples are presented, including the use of uranium ore bodies to assess waste form stability, the investigation of native metals to define the longevity of waste containers and how natural clays can provide information on the stability of waste tunnel backfill material. © 2015, Swiss Geological Society. Source

Kowe R.,Radioactive Waste Management | Delay J.,Agence National pour la Gestion des Dechets Radioactifs | Hammarstrom M.,Svensk Karnbranslehantering AB | Beattie T.,MCM Consulting | Palmu M.,Posiva Oy
Mineralogical Magazine | Year: 2015

The Implementing Geological Disposal of Radioactive Waste Technology Platform (IGD-TP) was launched in November 2009 to facilitate international cooperation in common areas of research, development and demonstration (RD&D) with a view to advancing the implementation of geological disposal facilities for spent fuel, high-level and other long-lived waste in Europe. The IGD-TP's Vision is that "by 2025, the first geological disposal facilities for spent fuel, high-level waste and other long-lived radioactive waste will be operating safely in Europe". Aside from most European waste management organisations, the IGD-TP currently has 124 members covering most of the RD&D actors in the field of implementing geological disposal of radioactive waste in Europe.. Five years after its inception, the IGD-TP has been shown to play a leading role in coordinating joint actions for RD&D in radioactive waste geological disposal programmes. The work of the platform takes into account differences between the timing and challenges for the respective waste management programmes. Following implementation of Posiva's geological disposal facility in Finland it is expected that within the next 5 years the construction of the Swedish and French geological disposal facilities will commence. Within IGD-TP, the SecIGD2 project whose remit is "Coordination and Support Action under the 7th Framework programme" aims at supporting, at the European level, the networking and structuring of RD&D programmes and competences in countries with less advanced geological disposal programmes, including those in the new European Union Member States. Furthermore, the SecIGD2 supports the development and coordination of the necessary competences to meet the Vision 2025 as a part of the platform's Competence Maintenance, Education and Training (CMET) working group. © 2016 by Walter de Gruyter Berlin/Boston. Source

Felipe-Sotelo M.,Loughborough University | Edgar M.,Loughborough University | Beattie T.,MCM Consulting | Warwick P.,Enviras Ltd. | And 2 more authors.
Journal of Hazardous Materials | Year: 2015

The influence of anthropogenic organic complexants (citrate, EDTA and DTPA from 0.005 to 0.1M) on the solubility of nickel(II), thorium(IV) and uranium (U(IV) and U(VI)) has been studied. Experiments were carried out in 95%-saturated Ca(OH)2 solutions, representing the high pH conditions anticipated in the near field of a cementitious intermediate level radioactive waste repository. Results showed that Ni(II) solubility increased by 2-4 orders of magnitude in the presence of EDTA and DTPA and from 3 to 4 orders of magnitude in the case of citrate. Citrate had the greatest effect on the solubility of Th(IV) and U(IV)/(VI). XRD and SEM analyses indicate that the precipitates are largely amorphous; only in the case of Ni(II), is there some evidence of incipient crystallinity, in the form of Ni(OH)2 (theophrastite). A study of the effect of calcium suggests that U(VI) and Ni(II) may form metal-citrate-OH complexes stabilised by Ca2+. Thermodynamic modelling underestimates the concentrations in solution in the presence of the ligands for all the elements considered here. Further investigation of the behaviour of organic ligands under hyperalkaline conditions is important because of the use of the thermodynamic constants in preparing the safety case for the geological disposal of radioactive wastes. © 2015 Elsevier B.V. Source

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