Abstract
Bentonites are candidate materials for encapsulating radioactive waste within barrier systems in crystalline rocks. In the ‘Alternative Buffer Material’ (ABM) test in the hard rock laboratory in Äspö, Sweden, six packages of eleven different buffer materials (mainly bentonites) with various exchangeable cation populations were packed vertically with an iron tube used as a heater in the center. After installation, the second ‘ABM package’ (ABM-II) was first allowed to saturate with water for approximately 2.5 years. The blocks were then exposed to a temperature of up to 141°C for approximately 3–4 years. The hypotheses for the present study were: (1) no horizontal gradient of the cation exchange population was present in the individual blocks of ABM-II because ABM-II had a longer reaction time in comparison to the ABM-I package, which did not have horizontal gradients; (2) the exchangeable cation Ca2+:Na+:Mg2+ ratio was equal in all blocks of ABM-II and was independent of block position in the package. As expected from ABM-I, all blocks in the ABM-II experiment showed large differences between the measured values of the reference materials and the reacted samples. The exchangeable Na+ and Mg2+ values in ABM-II were reduced by up to 55% to 59% in comparison to the reference material. Contrary to the first hypothesis, horizontal gradients were observed in ABM-II; and, contrary to the second hypothesis, the exchangeable cation ratios differed markedly in the different reacted buffer materials. The largest total Na+ loss was observed in the middle part (-67%), whereas Mg2+ values decreased by 79% in the upper part. The exchangeable Ca2+ values increased strongly in ABM-II, particularly in the upper part. The most useful parameter to distinguish between ion exchange equilibria of ABM-I and ABM-II was the Na+/Mg2+ ratio. This ratio was constant in ABM-I (3.0) and had a similar ratio (3.5) in the lower part of ABM-II; however, the ratio strongly increased (5–10) in the upper part of the ABM-II package. The large Na+/Mg2+ ratios in the upper part of ABM-II could possibly be explained by water loss into the rock (caused by a pressure drop and boiling) and subsequent water uptake.
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Balmer, S., Kaufhold S., and Dohrmann, R. (2017) Cementbentonite-iron interactions on small scale tests for testing performance of bentonites as a barrier in high-level radioactive waste repository concepts. Applied Clay Science, 135, 427–436.
Bourg, I.C., Sposito, G., and Bourg, A.C.M. (2006) Tracer diffusion in compacted, water-saturated bentonite. Clays and Clay Minerals, 54, 363–374.
Dixon, D.A., Martino, J.B., Vigna, I.B., Masumoto, K., and Fujita T. (2007) Overview of the evolution, performance and state of a bentonite-based tunnel seal after 5 years of operation. Physics and Chemistry of the Earth, 32, 741–752.
Dohrmann, R. (2006) Cation Exchange Capacity Methodology III: Correct exchangeable calcium determination of calcareous clays using a new silver-thiourea method. Applied Clay Science, 34, 47–57.
Dohrmann, R., Genske, D., Karnland, O., Kaufhold, S., Kiviranta, L., Olsson, S., Plötze, M., Sandén, T., Sellin, P., Svensson, D., and Valter, M. (2012a) Interlaboratory exchange of CEC and exchangeable cation results of bentonite buffer material. I. Cu(II)-triethylenetetramine method. Clays and Clay Minerals, 60, 162–175.
Dohrmann, R., Genske, D., Karnland, O., Kaufhold, S., Kiviranta, L., Olsson, S., Plötze, M., Sandén, T., Sellin, P., Svensson, D., and Valter, M. (2012b) Interlaboratory exchange of CEC and exchangeable cation results of bentonite buffer material. II. Alternative methods. Clays and Clay Minerals, 60, 176–185.
Dohrmann, R. and Kaufhold, S. (2009) Three new, quick CEC methods for determining the amounts of exchangeable calcium cations in calcareous clays. Clays and Clay Minerals, 57, 338–352.
Dohrmann, R. and Kaufhold, S. (2010) Determination of exchangeable calcium of calcareous and gypsiferous bentonites. Clays and Clay Minerals, 58, 513–522.
Dohrmann, R., Kaufhold, S., and Lundqvist, B. (2013a.) The role of clays for safe storage of nuclear waste. Pp. 677–710 in: Handbook of Clay Science, Techniques and Applications (F. Bergaya and G. Lagaly, editors). Developments in Clay Science, Vol. 5B, Elsevier, Amsterdam.
Dohrmann, R., Olsson, S., Kaufhold, S., and Sellin, P. (2013b) Mineralogical investigations of the first package of the alternative buffer material test — II. Exchangeable cation population rearrangement. Clay Minerals, 48, 215–233.
Dohrmann, R. and Kaufhold, S. (2014) Cation exchange and mineral reactions observed in MX 80 buffers samples of the prototype repository in situ experiment in Äspö, Sweden. Clays and Clay Minerals, 62, 357–373.
Elert, K., Pardo, E.S., and Rodriguez-Navarro, C. (2015) Mineralogical evolution of di- and trioctahedral smectites in highly alkaline environments. Clays and Clay Minerals, 63, 414–431.
Eng, A., Nilsson, U., and Svensson, D. (2007) Äspö Hard Rock Laboratory, Alternative Buffer Material Installation report IPR-07-15, 67 p., https://doi.org/skb.se/upload/publications/pdf/ipr-07-15.pdf
Ferrage, E. (2016) Investigation of the interlayer organization of water and ions in smectite from the combined use of diffraction experiments and molecular simulations. A review of methodology, applications, and perspectives. Clays and Clay Minerals, 64, 348–373.
Fröhlich, D.R. (2015) Sorption of neptunium on clays and clay minerals — A review. Clays and Clay Minerals, 63, 262–276.
Gómez-Espina, R. and Villar, M.V. (2016) Time evolution of MX-80 bentonite geochemistry under thermo-hydraulic gradients. Clay Minerals, 51, 145–160.
Grolimund, D., Wersin, P., Brendlé, J., Huve, J., Kiviranta, L., and Snellman, M. (2016) Interaction of titanium with smectite within the scope of a spent fuel repository: A spectroscopic approach. Clay Minerals, 51, 249–266.
Holmboe, M. and Bourg, I.C. (2013) Molecular dynamics simulations of water and sodium diffusion in smectite interlayer nanopores as a function of pore size and temperature. The Journal of Physical Chemistry C, 118, 1001–1013.
Holmboe, M., Wold, S., and Jonsson, M. (2010) Colloid diffusion in compacted bentonite: microstructural constraints. Clays and Clay Minerals, 58, 532–541.
Ishidera, T., Kurosawa, S., Hayashi, M., Uchikoshi, K., and Beppu, H. (2016) Diffusion and retention behaviour of Cs in illite-added compacted montmorillonite. Clay Minerals, 51, 161–172.
Johannesson, L.-E., Börgesson, L., Goudarzi, R., Sandén, T., Gunnarsson, D., and Svemar, C. (2007) Prototype repository: A full-scale experiment at Äspö HRL. Physics and Chemistry of the Earth, 32, 58–76.
Karnland, O., Olsson, S., and Nilsson, U. (2006) Mineralogy and Sealing Properties of Various Bentonites and Smectiterich Clay Materials. SKB technical report, TR 06–30.
Kaufhold, S. and Dohrmann, R. (2008) Detachment of colloids from bentonites in water. Applied Clay Science, 39, 50–59.
Kaufhold, S. and Dohrmann, R. (2016) Assessment of parameters to distinguish suitable from less suitable highlevel-radioactive waste bentonites. Clay Minerals, 51, 289–302.
Kaufhold, S., Dohrmann, R., Koch, D., and Houben, G. (2008) The pH of aqueous bentonite suspensions. Clays and Clay Minerals, 56, 338–343.
Kaufhold, S., Dohrmann, R., Sandén, T., Sellin, P., and Svensson, D. (2013). Mineralogical investigations of the alternative buffer material test — I. Alteration of bentonites. Clay Minerals, 48, 199–213.
Kaufhold, S., Dohrmann, R., and Ufer, K. (2016) Interaction of magnesium cations with dioctahedral smectites under HLRW repository conditions. Clays and Clay Minerals, 64, 743–752.
Kaufhold S., Dohrmann, R., Götze, N., and Svensson, D. (2017a). Characterization of the second parcel of the alternative buffer material (ABM) experiment — I mineralogical reactions. Clays and Clay Minerals, 65, 27–41.
Kaufhold, S. Dohrmann, R., and Gröger-Trampe, J. (2017b) Reaction of native copper in contact with pyrite and bentonite in anaerobic water at elevated temperature. Corrosion Engineering, Science and Technology, doi: https://doi.org/10.1080/1478422X.2017.1292201
Kaufhold, S., Sanders, D., Hassel, A.-W., and Dohrmann, R. (2015) Corrosion of high-level radioactive waste ironcanisters in contact with bentonite. Journal of Hazardous Materials, 285, 464–473.
Kaufhold S., Stucki, J.W., Finck, N., Steininger, R., Zimina, A., Dohrmann, R., Ufer, K., Pentrák, M., and Pentráková, L. (2017c). Tetrahedral charge and Fe-content in dioctahedral smectites. Clay Minerals, 52, 51–65
Keller, L.M., Seiphoori, A., Gasser, P., Lucas, F., Holzer, L., and Ferrari, A. (2014) The pore structure of compacted and partly saturated MX-80 bentonite at different dry densities. Clays and Clay Minerals, 62, 174–187.
Kerisit, S., Okumura, M., Rosso, K., and Mashida, M. (2016) Molecular simulation of cesium adsorption at the basal surface of phyllosilicate minerals. Clays and Clay Minerals, 64, 389–400.
Klika, Z., Seidlerová, J., Valášková, M., Kliková, C., and Kolomazník, I. (2016) Uptake of Ce(III) and Ce(IV) on montmorillonite. Applied Clay Science, 132-133, 41–49.
Kosec, T., Qin, Z., Chen, J., Legat, A., and Shoesmith, D.W. (2015) Copper corrosion in bentonite/saline groundwater solution: Effects of solution and bentonite chemistry. Corrosion Science, 90, 248–258.
Kumpulainen, S. and Kiviranta, L. (2011) Mineralogical, chemical and physical study of potential buffer and backfill materials from ABM test package 1. Posiva Working Report 2011–41. Posiva Oy, Olkiluoto, Finland. Available online at: https://doi.org/www.iaea.org/inis/collection/NCLCollectionStore/_Public/43/068/43068661.pdf.
Kumpulainen, S., Kiviranta, L., and Korkeakoski, P. (2016) Long-term effects of Fe-heater and \:Asp\:o groundwater on smectite clays — Chemical and hydromechanical results from in situ alternative buffer material (ABM) test package 2. Clay Minerals, 51, 129–144.
Mayordomo, N., Degueldre, C. Alonso, U., and Missana, T. (2016) Size distribution of FEBEX bentonite colloids upon fast disaggregation in low ionic strength water. Clay Minerals, 51, 213–222.
Meier, L.P. and Kahr, G. (1999) Determination of the cation exchange capacity (CEC) of clay minerals using the complexes of copper (II) ion with triethylenetetramine and tetraethylenepentamine. Clays and Clay Minerals, 47, 386–388.
Missana, T., Alonso, U., Albarran, N., García-Gutiírrez, M., and Cormenzana, J.-L. (2011) Analysis of colloids erosion from the bentonite barrier of a high level radioactive waste repository and implications in safety assessment. Physics and Chemistry of the Earth, Parts A/B/C, 36, 1607–1615.
Olsson, S. and Karnland, O. (2011) Mineralogical and chemical characteristics of the bentonite in the A2 test parcel of the LOT field experiments at \:Asp\:o HRL, Sweden. Physics and Chemistry of the Earth, 36, 1545–1553.
Peng, Y., Zhang, H., Yang, B., Wang, X., Shao, X., and Liu, P. (2016) Ice-bentonite powder mixing method to improve the homogeneity of compacted bentonite in an initial sample preparation stage. Clays and Clay Minerals, 64, 706–718.
Plötze, M., Kahr, G., Dohrmann, R., and Weber, H. (2007) Hydro-mechanical, geochemical and mineralogical characteristics of the bentonite buffer in a heater experiment. The HE-B project at the Mont Terri rock laboratory. Physics and Chemistry of the Earth, 32, 730–740.
Rivard, C., Pelletier, M., Michau, N., Razafitianamaharavo, A., Abdelmoula, M., Ghanbaja, J., and Villiéras, F. (2016) Reactivity of Callovo-Oxfordian claystone and its clay fraction with metallic iron: Role of non-clay minerals in the interaction mechanism. Clays and Clay Minerals, 63, 290–310.
Samper, J., Naves, A., Montenegro, L., and Mon, A. (2016) Reactive transport modelling of the long-term interactions of corrosion products and compacted bentonite in a HLW repository in granite: Uncertainties and relevance for performance assessment. Applied Geochemistry, 67, 42–51.
Sasamoto, H., Isogai, B., Kikuchi, H., Satoh, H., and Svensson, D. (2017) Mineralogical, physical and chemical investigation of compacted Kunigel V1 bentonite in contact with a steel heater in the ABM test package 1 experiment, Äspö laboratory, Sweden. Clay Minerals, 52, 127–141.
Sellin, P. and Leupin, O. (2014) The use of clay as an engineered barrier in radioactive waste management — a review. Clays and Clay Minerals, 61, 477–498.
SKB (2007) RD&D Programme 2007. Programme for research, development and demonstration of methods for the management and disposal of nuclear waste. TR-07–12, Swedish Nuclear Fuel and Waste Management Company (SKB), Stockholm, Sweden. https://doi.org/www.skb.se/upload/publications/pdf/TR-07-12_FUD_2007_eng_webb.pdf. SKB (2014) Äspö Hard Rock Laboratory, Annual Report 2013.
TR-14-17, Swedish Nuclear Fuel and Waste Management Company (SKB), Stockholm, Sweden. https://doi.org/www.skb.com/publication/2720398/TR-14-17.pdf.
Stanjek, H. and Künkel, D. (2016) CEC determination with Cutriethylenetetramine: recommendations for improving reproducibility and accuracy. Clay Minerals, 51, 1–17.
Svensson D., Dueck A., Nilsson U., Olsson S., Sandén T., Lydmark S., Jägerwall S., Pedersen K., and Hansen S. (2011) Alternative Buffer Material. Status of the Ongoing Laboratory Investigation of Reference Materials and Test Package 1. TR-11-06. Svensk Kärnbränslehantering AB (SKB), Stockholm, Sweden. https://doi.org/skb.se/upload/publications/pdf/TR-11-06.pdf.
Szakálos, P. and Seetharaman, S. (2012) Corrosion of Copper. Technical Note 2012:17. Report number: 2012:17 ISSN: 2000-0456.
Tournassat, C., Bourg, I., Holmboe, M., Sposito, G., and Steefel, C.I. (2016) Molecular dynamics simulations of anion exclusion in clay interlayer nanopores. Clays and Clay Minerals, 64, 74–388.
van Geet, M. and Dohrmann, R. (2016) Overview of the clay mineralogy studies presented at the ‘Clays in natural and engineered barriers for radioactive waste confinement’ meeting, Brussels, March 2015. Clay Minerals, 51, 125–128.
Wallis, I., Idiart, A., Dohrmann, R., and Post, V. (2016) Reactive transport modelling of groundwater-bentonite interaction: effects on exchangeable cations in an alternative buffer material in-situ test. Applied Geochemistry, 73, 59–69.
Wersin, P. and Birgersson, M. (2014) Reactive transport modelling of iron-bentonite interaction within the KBS- 3H disposal concept: the Olkiluoto site as a case study. in: Geological Society, London, Special Publications 2014, vol. 400, pp. 237–250. doi:https://doi.org/10.1144/SP400.24.
Wersin, P., Jenni, A., and Mäder, U.K. (2015) Interaction of corroding iron with bentonite in the ABM1 Experiment at Äspö, Sweden: A microscopic approach. Clays and Clay Minerals, 63, 51–58.
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Dohrmann, R., Kaufhold, S. Characterization of the Second Package of the Alternative Buffer Material (ABM) Experiment — II Exchangeable Cation Population Rearrangement. Clays Clay Miner. 65, 104–121 (2017). https://doi.org/10.1346/CCMN.2017.064052
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DOI: https://doi.org/10.1346/CCMN.2017.064052