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Disposal of high-level nuclear wastes: a geological perspective

Published online by Cambridge University Press:  05 July 2018

A. E. Ringwood*
Affiliation:
Research School of Earth Sciences, Australian National University, Canberra, Australia

Abstract

Most countries intend to dispose of their high-level radioactive wastes by converting them into a solidified wasteform which is to be buried within the earth. SYNROC is a titanate ceramic wasteform which has been designed for this purpose on the basis of geochemical principles. It comprises essentially rutile TiO2, ‘hollandite’ Ba(Al,Ti)Ti6O16, zirconolite CaZrTi2O7, and perovskite CaTiO3. The latter three phases have the capacity to accept the great majority of radioactive elements occurring in high-level wastes into their crystal lattice sites. These minerals (or their close relatives) also occur in nature, where they have demonstrated their capacity to survive for many millions of years in a wide range of geological environments. The properties of SYNROC and the crystal chemistry of its constituent minerals are reviewed in some detail and current formulations of SYNROC are summarized. A notable property of SYNROC it its extremely high resistance to leaching by groundwaters, particularly above 100°C. In addition, it can be shown that the capacity of SYNROC minerals to immobilize high-level waste elements is not markedly impaired by high levels of radiation damage. Current investigations are focused on developing a satisfactory production technology for SYNROC and progress towards this objective is described. The high leach resistance of SYNROC at elevated temperatures increases the range of geological environments in which the waste may be finally interred; in particular, SYNROC is well adapted for disposal in deep drill-holes, both in continental and marine environments. The fact that SYNROC is comprised of minerals which have demonstrated long-term geological stability is significant in establishing public confidence in the ability of the nuclear industry to immobilize high-level wastes for the very long periods required.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1985

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References

Bauer, C., and Ondracek, G. (1983) In Scientific Basis for Nuclear Waste Management, 6 (Brookins, D., ed.) Elsevier, New York, 71-6.Google Scholar
Bayer, G., and Hoffman, W. (1966) Am. Mineral 51, 511-16.Google Scholar
Bonniaud, R., Jouan, A., and Sombret, C. (1980) Nucl. Chem. Waste Manag. 1, 316.CrossRefGoogle Scholar
Castaing, R. A. (1982) (Chairman) Working group on the management of spent nuclear fuel. Report to the French Government.Google Scholar
Clinard, F. W., Hobbs, L. W., Land, C. C., Peterson, D. E., Rohr, D. L., and Roof, R. G. (1982) J. Nucl. Mater. 105, 248-56.CrossRefGoogle Scholar
Coles, D. G., Weed, H. C., and Schweiger, L. S. (1978) In Radioactive waste in Geologic Storage (Fried, S., ed.) ACS Symposium Series 100, 93 pp.CrossRefGoogle Scholar
Forberg, S., Westermark, T., Larker, H., and Widell, B. (1979) Ibid. 1 (McCarthy, G., ed.) 201-5.Google Scholar
Gatehouse, B. M., Grey, I. E., Hill, R. J., and Rossell, H. J. (1981) Acta Crystallogr. B37, 306-12.CrossRefGoogle Scholar
Hespe, E. D. (1971) Atomic Energy Review, 9, 112.Google Scholar
KBS (Kärnebränslesäkerhet) (1978) Report on handling of spent nuclear fuel and final storage of vitrified high level waste (5 vols.) Teleplan, Sweden, 1978.Google Scholar
Kesson, S. E. (1983) The immobilization of cesium in SYNROC hollandite. Rad. Waste Manag. and the Nuclear Fuel Cycle, 4, 5372.Google Scholar
Kesson, S. E. and Ringwood, A. E. (1981) Nucl. Chem. Waste Manag. 2, 53-5.CrossRefGoogle Scholar
Kesson, S. E. and Ringwood, A. E. (1983) Safe disposal of spent nuclear fuel. Rad. Waste Manag. and the Nucl. Fuel Cycle, in press.Google Scholar
Kesson, S. E. and Ringwood, A. E. (1984) Immobilization of HLW in SYNROC-E Mat. Res. Soc. Syrup. Proc. 26, 507-12.CrossRefGoogle Scholar
Kesson, S. E., Sinclair, W. J., and Ringwood, A. E. (1983) Solid solution limits in SYNROC zirconolite. Nucl. Chem. Waste Manag. in press.Google Scholar
Levins, D., and Smart, R. (1984) Nature, 309, 776-8.CrossRefGoogle Scholar
McCarthy, G. J. (1977) Nucl. Technol. 32, 92-105.CrossRefGoogle Scholar
Mazzi, F., and Munno, R. (1983) Am. Mineral. 68, 262.Google Scholar
Mendel, J. E., Ross, W. A., Roberts, F. P., Katayama, Y., Westsik, J., Turcotte, R., Wald, J., and Bradley, D. (1977) Annual report on the characteristics of high-level waste glasses, Battelle Pacific Northwest Lab. Report BWNL-2252, UC-70, pp. 1-99.Google Scholar
Morner, N. A. (1978) Geology, 6, 41-5.2.0.CO;2>CrossRefGoogle Scholar
NAS (1983) A Study of the Isolation System for Geologic Disposal of Radioactive Wastes. Waste Isolation Systems Panel, Board on Radioactive Waste Management, National Academy of Sciences, 356 pp., ISBN 0-309-03384-5.Google Scholar
Nesbitt, H. W., Bancroft, G. M., Fyfe, W. S., Karkhanis, S. N., and Shin, S. (1981) Nature, 289, 358-62.CrossRefGoogle Scholar
Norrish, K. (1951) Mineral. Mag. 29, 496501.Google Scholar
Oversby, V. M., and Ringwood, A. E. (1981) Radioactive Waste Management, 1, 289-307.Google Scholar
Oversby, V. M., and Ringwood, A. E. (1982) Ibid. 2, 22338.Google Scholar
Ramm, E., and Ringwood, A. E. (1980) Arrangements for containing waste material. Austral. Patent Application No. PE453G. Google Scholar
Ramm, E., and Ringwood, A. E. (1982) Containment of waste material. Austral. Patent Application No. PF5760. Google Scholar
Reeve, K. D., and Woolfrey, J. L. (1980) Austral. Ceram. Soc. J. 16, 10-15.Google Scholar
Ringwood, A. E. (1978) Safe disposal of high level nuclear reactor wastes: A new strategy. Austral. Nat. Univ. Press, Canberra, 64 pp.Google Scholar
Ringwood, A. E. (1980a) Search, 11, No. 10, 323-30.Google Scholar
Ringwood, A. E. (1980b) Fortschr. Mineral. 58(2), 149-68.Google Scholar
Ringwood, A. E., Kesson, S. E., and Ware, N. G. (1980) Scientific Basis for Nuclear Waste Management, 2 (McCarthy, G., ed.) Plenum Press, New York, 265-72.CrossRefGoogle Scholar
Hibberson, W. and Major, A. (1979a) Nature, 278, 219-23.Google Scholar
Hibberson, W. and Major, A. (1979b) Geochem. J. 13, 141-65.Google Scholar
Hibberson, W., Major, A., Ramm, E. J., and Padgett, J. (1983) Uniaxial hot-pressing in bellows containers. Nucl. Chem. Waste Management, 4, 135-40.Google Scholar
Hibberson, W., Oversby, V. M., Kesson, S., Sinclair, W., Ware, N., Hibberson, W., and Major, A. (1981) Ibid., 2, 287 305.Google Scholar
Hibberson, W. and Willis, P. E. (1984) Nature, 311, 735-7.Google Scholar
Rossell, H. J. (1980) Nature, 283, 282-3.CrossRefGoogle Scholar
Roth, R. (1981) In National Measurement Laboratory Office of Measurements for Nuclear Technology Annual Report 1981. NBSIR 81-2241, 42.Google Scholar
Ryerson, F. J. (1983) SYNROC-D: Microstructure and mineral chemistry. J. Am. Ceram. Soc. in press.CrossRefGoogle Scholar
Sinclair, W., and Eggleton, R. A. (1982) Am. Mineral. 67, 615-20.Google Scholar
Sinclair, W., McLaughlin, G. M., and Ringwood, A. E. (1981) Acta Cryst. B56, 2913-18.Google Scholar
Sinclair, W. and Ringwood, A. E. (1981) Geochem. J. 15, 229-43.CrossRefGoogle Scholar
Tafto, J., Clarke, D. R., and Spence, C. M. (1983) In Scientific Basis for Nuclear Waste Management, 6 (Brookins, D., ed.) Elsevier, New York, 913.Google Scholar
Tempest, P. A. (1981) Nucl. Technol. 52, 415-25.CrossRefGoogle Scholar