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The Use of Clay as an Engineered Barrier in Radioactive-Waste Management — A Review

Published online by Cambridge University Press:  01 January 2024

Patrik Sellin  and
Olivier X. Leupin
Patrik Sellin*
Affiliation:
SKB [Swedish Nuclear Fuel and Waste Management Company], Stockholm, Sweden
Olivier X. Leupin
Affiliation:
NAGRA [Nationale Genossenschaft für die Lagerung radioaktiver Abfälle, Wettingen, Switzerland
*
*E-mail address of corresponding author: patrik.sellin@skb.se
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Abstract

Geological disposal is the preferred option for the final storage of high-level nuclear waste and spent nuclear fuel in most countries. The selected host rock may be different in individual national programs for radioactive-waste management and the engineered barrier systems that protect and isolate the waste may also differ, but almost all programs are considering an engineered barrier. Clay is used as a buffer that surrounds and protects the individual waste packages and/or as tunnel seal that seals off the disposal galleries from the shafts leading to the surface.

Bentonite and bentonite/sand mixtures are selected primarily because of their low hydraulic permeability in a saturated state. This ensures that diffusion will be the dominant transport mechanism in the barrier. Another key advantage is the swelling pressure, which ensures a self-sealing ability and closes gaps in the installed barrier and the excavation-damaged zone around the emplacement tunnels. Bentonite is a natural geological material that has been stable over timescales of millions of years and this is important as the barriers need to retain their properties for up to 106 y.

In order to be able to license a final repository for high-level radioactive waste, a solid understanding of how the barriers evolve with time is needed. This understanding is based on scientific knowledge about the processes and boundary conditions acting on the barriers in the repository. These are often divided into thermal, hydraulic, mechanical, and (bio)chemical processes. Examples of areas that need to be evaluated are the evolution of temperature in the repository during the early stage due to the decay heat in the waste, re-saturation of the bentonite blocks installed, build-up of swelling pressure on the containers and the surrounding rock, and degradation of the montmorillonite component in the bentonite. Another important area of development is the engineering aspects: how can the barriers be manufactured, subjected to quality control, and installed?

Geological disposal programs for radioactive waste have generated a large body of information on the safety-relevant properties of clays used as engineered barriers. The major relevant findings of the past 35 y are reviewed here.

Keywords

BentoniteBarrierNuclear WasteGeological DisposalWaste Management
Type
Review Article
Information
Clays and Clay Minerals , Volume 61 , Issue 6 , December 2013 , pp. 477 - 498
Copyright
Copyright © Clay Minerals Society 2013

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References

AECL, 1994 Environmental Impact Statement on the Concept for Disposal of Canada’s Nuclear Fuel Waste .Google Scholar
ANDRA, 2005 Dossier 2005 Argile: Architecture and management of a geological repository .Google Scholar
Appelo, C A J Van Loon, L.R. and Wersin, P., 2010 Multicomponent diffusion of a suite of tracers (HTO, Cl. Br, I, Na, Sr, Cs) in a single sample of Opalinus Clay. Geochimica et Cosmochimica Acta 74 1201–1219.CrossRefGoogle Scholar
Birgersson, M. Karnland, O. and Nilsson, U., 2008 Freezing in saturated bentonite - A thermodynamic approach. Physics and Chemistry of the Earth 33 527–530.CrossRefGoogle Scholar
Birgersson, M. and Karnland, O., 2009 Ion equilibrium between montmorillonite interlayer space and an external solution - consequences for diffusional transport. Geochimica et Cosmochimica Acta 73 1908–1923.CrossRefGoogle Scholar
Birgersson, M. Karnland, O. and Nilsson, U., 2010.Freezing of bentoniteGoogle Scholar
Bock, H. Dehandschutter, B. Martin, C. D. Mazurek, M. de Haller, A. Skoczylas, F. and Davy, C., 2010.Self-sealing of fractures in argillaceous formations in the context of geological disposal of radioactive wasteGoogle Scholar
Börgesson, L. Fredrikson, A. and Johannesson, L.-E., 1994.Heat conductivity of buffer materialsGoogle Scholar
Bradbury, M. H. and Baeyens, B., 2005 Experimental measurements and modelling of sorption competition on montmorillonite. Geochimica et Cosmochimica Acta 69 4187–4197.CrossRefGoogle Scholar
Bradbury, M. H. (in prep.) Long Term Geochemical Evolution of the Near-Field of a SF/HLW Radioactive Waste Repository. Nagra Tech. Report NTB 12-01. Nagra, Wettingen, Switzerland.Google Scholar
Burst, J. F., 1959 Post diagenetic clay mineral-environmental relationships in the Gulf Coast Eocene in clays and clay minerals. Clays and Clay Minerals 6 327–341.CrossRefGoogle Scholar
Cuss, R. J. Harrington, J. F. Noy, D. J. Wikman, A. and Sellin, P., 2011 Large-scale gas injection test (Lasgit): Results from two gas injection tests. Physics and Chemistry of the Earth 36 1729–1742.CrossRefGoogle Scholar
Dixon, D. A. Gray, M. N. and Graham, J., 1996 Swelling and hydraulic properties of bentonites from Japan, Canada and USA. Proceedings of the second International Congress on Environmental Geotechnics, Osaka, Japan 5–8.Google Scholar
Dueck, A. Börgesson, L. and Johannesson, L.-E., 2010.Stress-strain relation of bentonite at undrained shearGoogle Scholar
Dueck, A. Johannesson, L.-E. Kristensson, O. Olsson, S. and Sjöland, A., 2011 Hydro-mechanical and chemical-miner-alogical analyses of the bentonite buffer from a full-scale field experiment simulating a high-level waste repository. Clay and Clay Minerals 59 595–607.CrossRefGoogle Scholar
Eberl, D. D., 1978 The reaction of montmorillonite to mixed-layer clay: The effect of interlayer alkali and alkaline earth cations. Geochimica et Cosmochimica Acta 42 1–7.CrossRefGoogle Scholar
Eberl, D. and Hower, J., 1976.Kinetics of illite formation. Geological Society of America Bulletin2.0.CO;2>CrossRefGoogle Scholar
ENRESA, 2000 FEBEX project .Google Scholar
Evans, D. F. and Wennerström, H., 1999 The Colloidal Domain: where Physics, Chemistry, Biology, and Technology Meet 2nd edition.Google Scholar
Graham, C. C. Harrington, J. F. Cuss, R. J. and Sellin, P., 2012 Gas migration experiments in bentonite: implications for numerical modelling. Mineralogical Magazine 76 3279–3292.CrossRefGoogle Scholar
Grambow, B. Fattahi, M. Montavon, G. Moisan, C. and Giffaut, E., 2006 Sorption of Cs, Ni, Pb, Eu(III), Am(III), Cm, Ac(III) on MX 80 bentonite: An experimental approach to assess model uncertainty. Radiochimica Acta 94 627–636.CrossRefGoogle Scholar
Gu, B.X. Wang, L.M. Minc, L.D. and Ewing, R.C., 2001 Temperature effects on the radiation stability and ion exchange capacity of smectites. Journal of Nuclear Materials 191 345–354.CrossRefGoogle Scholar
Güven, N. and Huang, W. L., 1991 Effect of octahedral Mg2+ and Fe3+ substitution on hydrothermal illitization reactions. Clays and Clay Minerals 39 387–399.CrossRefGoogle Scholar
Harrington, J.F. Volckaert, G. and Noy, D.J., 2014.Long-term impact of temperature on the hydraulic permeability of bentonite Clays in Matural and Engineering Barriers for Radioactive Waste ConfinementCrossRefGoogle Scholar
Hetzel, F. and Doner, H.E., 1993 Some colloidal properties of beidellite: comparison with low and high charge montmorillonite. Clays and Clay Minerals 41 453–460.CrossRefGoogle Scholar
Hökmark, H. Lönnqvist, M. and Fälth, B., 2010.THM-issues in repository rockGoogle Scholar
Horton, D.G., 1985 Mixed-layer illite/smectite as a paleo-temperature indicator in the Amethyst vein system, Creed, Colorado, USA Contributions to Mineralogy and Petrology 91 171–179.CrossRefGoogle Scholar
Hower, J. and Mowatt, T.C., 1966 The mineralogy of illites and mixed-layer illite/montmorillonites. American Mineralogist 51 825–854.Google Scholar
Huang, W.-L. Longo, J.M. and Pevear, D.R., 1993 An experimentally derived kinetic model for smectite-to-illite conversion and its use as a geothermometer. Clays and Clay Minerals 41 162–177.CrossRefGoogle Scholar
Huber, F. Kunze, P. Geckeis, H. and Schafer, T., 2011 Sorption reversibility kinetics in the ternary system radio-nuclide-bentonite colloids/nanoparticles-granite fracture filling material. Applied Geochemistry 26 2226–2237.CrossRefGoogle Scholar
Huertas, F. Fuentes-Cantilliana, J.L. Rivas, F. Linares, J. Farina, P. Jockwer, N. Kickmaier, W. Martinet, M.A. Samper, J. Alonso, E. and Elorza, F.S., 2000.Full scale engineered barriers experiment for a high level radioactive waste in crystalline host rock (FEBEX project): final reportGoogle Scholar
Huertas, F.J. Caballero, E. de Jiménez Cisneros, C. Huertas, F. and Linares, J., 2001 Kinetics of montmorillonite dissolution in granitic solutions. Applied Geochemistry 16 397–407.CrossRefGoogle Scholar
IAEA International Atomic Energy Agency, 2003 Scientific and Technical Basis for the Geological Disposal of Radioactive Wastes .Google Scholar
Jennings, S. and Thompson, G.R., 1986 Diagenesis of Plio-Pleistocene sediments of the Colorado River Delta, Southern California. Journal of Sedimentary Petrology 56 89–98.Google Scholar
JNC, 2000 H12: Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan, Project Overview Report .Google Scholar
Johnson, L. and King, F., 2008 The effect of the evolution of environmental conditions on the corrosion evolutionary path in a repository for spent fuel and high-level waste in Opalinus Clay. Journal of Nuclear Materials 379 9–15.CrossRefGoogle Scholar
Karnland, O. Olsson, S. and Nilsson, U., 2006.Mineralogy and sealing properties of various bentonites and smectite-rich clay materials SKB TR 06-30, Svensk Kärnbränslehantering AB, SwedenGoogle Scholar
Karnland, O., Nilsson, U., Weber, H., and Wersin, P. (2008) Sealing ability of Wyoming bentonite pellets foreseen as buffer material-Laboratory results. Physics and Chemistry of the Earth, 33, S472-S475 Parts A/B/C.Google Scholar
Kim, J.W. Dong, H. Seabaugh, J. Newell, S.W. and Eberl, D.D., 2004 Role of microbes in the smectite-to-illite reaction. Science 303 830–832.CrossRefGoogle ScholarPubMed
Komine, H. and Ogata, N., 1994 Prediction for swelling characteristics of compacted bentonite. Canadian Geotechnical Journal 33 11–22.CrossRefGoogle Scholar
Komine, H. and Ogata, N., 2004 Predicting swelling characteristics of bentonites. Journal of Geotechnical & Geoenvironmental Engineering 130 818–830.CrossRefGoogle Scholar
Kristensson, O. and Åkesson, M., 2011 Homogenization of engineered barriers, simulations verified against Canister Retrieval Test data. Physics and Chemistry of the Earth 36 1848–1856.CrossRefGoogle Scholar
Kurosawa, S. Yui, M. Yoshikawa, H., Gray, W. J. and Triay, I.R., 1997 Experimental study of colloid filtration by compacted bentonite Scientific basis for nuclear waste management XX Symposium 963–970.CrossRefGoogle Scholar
Liu, L. Moreno, L. and Neretnieks, I., 2009 A dynamic force balance model for colloidal expansion and its DLVO-based application Langmuir 25 679–687.CrossRefGoogle ScholarPubMed
Madsen, F. and Müller-Vonmoos, M., 1989 The swelling behaviour of clays. Applied Clay Science 4 143–156.CrossRefGoogle Scholar
Madsen, F.T., 1998 Clay mineralogical investigations related to nuclear waste disposal. Clay Minerals 33 109–129.CrossRefGoogle Scholar
Marschall, P. Horseman, S. and Gimmi, T., 2005 Characterisation of gas transport properties of Opalinus Clay, a potential host rock formation for radioactive waste disposal. Oil & Gas Science and Technology 60 121–139.CrossRefGoogle Scholar
Metcalfe, R. and Walker, C., 2004.Proceedings of the International Workshop on Bentonite-Cement Interaction in Repository Environments 14–16 April 2004, Tokyo, JapanGoogle Scholar
Missana, T. Alonso, U. and Garcia-Gutiérrez, M., 2009 Experimental study and modelling of selenite sorption onto illite and smectite clays. Journal of Colloid and Interface Science 334 132–138.CrossRefGoogle ScholarPubMed
NAGRA, 2002 Project Opalinus Clay Safety Report: Demonstration of disposal feasibility for spent fuel, vitrified high-level waste and long-lived intermediate-level waste (Entsorgungsnachweis) NAGRA Tech .Google Scholar
NAGRA, 2008 Vorschlag geologischer Standortgebiete für das SMA- und das HAA-Lager: Darlegung der Anforderungen, des Vorgehens und der Ergebnisse [Einengungsbericht] .Google Scholar
NAGRA, 2010 Beurteilung der geologischen Unterlagen fur die provisorischen Sicherheitsanalysen in SGT Etappe 2 -Klärung der Notwendigkeit ergänzender geologischer Untersuchungen .Google Scholar
Neretnieks, L. Liu, L. and Moreno, L., 2009.Mechanisms and models for bentonite erosion. SKB Technical Report TR-09-35Google Scholar
Norrish, K., 1954 Manner of swelling of montmorillonite. Nature 173 256–257.CrossRefGoogle Scholar
Nuclear Waste Management Organization/OECD/NEA, 1995 The Environmental and Ethical Basis of Geological Disposal of Long-Lived Radioactive Wastes .Google Scholar
Nuclear Waste Management Organization, 2012 Description of Canada’s Repository for Used Nuclear Fuel and Centre of Expertise .Google Scholar
Petsev, D.N. Starov, V.M. and Ivanov, I.B., 1993 Concentrated dispersions of charged colloidal particles: sedimentation, ultrafiltration and diffusion. Colloids and Surfaces A: Physicochemical and Engineering Aspects 81 65–81.CrossRefGoogle Scholar
Plötze, M. and Valter, M., 2011.Bentonite as barrier material - thermal conductivity of compacted bentoniteGoogle Scholar
Pusch, R. Karnland, O. Lajudie, A. and Decarreau, A., 1993.MX 80 clay exposed to high temperatures and gamma radiationGoogle Scholar
Pusch, R. Kasbohm, J. and Thao, H.T.M., 2010 Chemical stability of montmorillonite buffer clay under repositorylike conditions - A synthesis of relevant experimental data. Applied Clay Science 47 113–119.CrossRefGoogle Scholar
Pytte, A.M., 1982.The kinetics of smectite to illite reaction in contact metamorphic shalesGoogle Scholar
Sato, T. Kuroda, M. Yokoyama, S. Tsutsui, M F K Tanaka, T. and Nakayama, S., 2004.Dissolution mechanism and kinetics of smectite under alkaline conditions Proceedings of the International Workshop on Bentonite-Cement Interaction in Repository EnvironmentGoogle Scholar
SKB, 2010 Design, production and initial state of the buffer .Google Scholar
SKB, 2011 Environmental Impact Statement, Interim storage, encapsulation and final disposal of spent nuclear fuel, March 2011, ISBN 978-91-978702-5-2 .Google Scholar
Sridharan, A., 1997 Prediction for swelling characteristics of compacted bentonite: Discussion Canadian Geotechnical Journal 34 1004.CrossRefGoogle Scholar
Stroes-Gascoyne, S., 2002.Assessment of the likelihood of significant microbial activity in Opalinus clayGoogle Scholar
Stroes-Gascoyne, S., 2011.Microbiological characteristics of compacted bentonite for a dry density of 1450 kg/m3: A literature reviewGoogle Scholar
Velde, B. and Vasseur, G., 1992 Estimation of the diagenetic smectite to illite transformation in time temperature space American Mineralogist 77 967–976.Google Scholar
Villar, M.V., 2007 Water retention of two natural compacted bentonites Clays and Clay Minerals 55 311–322.CrossRefGoogle Scholar
Villar, M.V. Martin, P.L. Romero, F.J. Barcala, J.M. Gutiérrez-Rodrigo, V., Skoczylas, F. Davy, C.A. Agostini, F. and Burlion, N., 2012 Gas transport through bentonite: influence of dry density, water content and boundary conditions Propriétés de Transfert des Géomatériaux 379–389.Google Scholar
Wang, Q. Tang, A.M. Cui, Y.-J. Delage, P. and Gatmiri, B., 2012 Experimental study on the swelling behaviour of bentonite/claystone mixture. Engineering Geology 124 59–66.CrossRefGoogle Scholar
Wersin, P. Curti, E. and Appelo, C.A.J., 2004 Modelling bentonite-water interactions at high solid/liquid ratios: swelling and diffuse double layer effects. Applied Clay Science 26 249–257.CrossRefGoogle Scholar
Yamaguchi, T. Sakamoto, Y. Akai, M. Takazawa, M Iida Y Tanaka, T. and Nakayama, S., 2007 Experimental and modeling study on long-term alteration of compacted bentonite with alkaline groundwater. Physics and Chemistry of the Earth 32 298–310.CrossRefGoogle Scholar
Zandarin, M.T. Gens, A. Olivella, S. and Alonso, E.E., 2012 Thermo-hydro-mechanical model of the Canister Retrieval Test. Physics and Chemistry of the Earth 36 1806–1816.CrossRefGoogle Scholar