Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-29T07:49:59.174Z Has data issue: false hasContentIssue false

Diffusion of Radionuclides in Brine-Saturated Backfill Barrier Materials*

Published online by Cambridge University Press:  21 February 2011

E. J. Nowak*
Affiliation:
Sandia National Laboratories, Albuquerque, New Mexico, 87185, USA
Get access

Abstract

The diffusion of cesium(I), strontium(II), pertechnetate and europium in brine-saturated backfill materials was measured. Plastic diffusion cells containing cylindrical diffusion columns were used for low density backfill materials. The diffusion of gamma-emitters was followed by a gamma scanning technique. Metal diffusion cells constructed entirely from Hastelloy C-276 were used for the diffusion of pertechnetate in highly compacted bentonite. Apparent distribution coefficients calculated from diffusion data are (a) 0.02 m3 /kg for cesium(I) in 40 wt.% mordenite and 60 wt.% bentonite; (b) 0.04 m3/kg for strontium(II) in 10 wt.% sodium titanate and 90 wt.% bentonite; (c) 0.5 m3/kg for pertechnetate in 70 wt.% charcoal and 30 wt.% bentonite; and (d) 3 m3/kg for europium in 100% bentonite. Backfill effectiveness estimates based on batch sorption measurements were supported by these results;however, the diffusion results for europium did not agree well with a model for diffusion retarded by linear sorption. First measurements of pertechnetate diffusion in highly compacted bentonite suggest that anion exclusion may play a role in reducing mass transport rates of anions in this material. Needs for diffusion measurements that take into account site-specific materials interactions are described.

Type
Research Article
Copyright
Copyright © Materials Research Society 1983

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

*

This work performed at Sandia National Laboratories supported by the U.S. Department of Energy under Contract DE-AC04-76DP00789.

References

REFERENCES

1. Roy, R., Earth and Mineral Sciences 50, 13 (1980).Google Scholar
2. Pusch, R., Nuclear Technology 45, 153 (1979).Google Scholar
3. Nowak, E. J., Sandia National Laboratories Report SAND79–1109 (1980).Google Scholar
4. Coons, W. E., Moore, E. L., Smith, M. J., and Kaser, J. D., Rockwell Hanford Operations Report RHO-BWI-LD-23 (1980).Google Scholar
5. KBS, Swedish Nuclear Fuel Safety Project (KBS) Annual Report KBS80–26 (1981).Google Scholar
6. Wood, B. J., Nuclear Technology, in press.Google Scholar
7. Allard, B., Rydberg, J., Kipatsi, H., and Torstenfelt, B. in: Radioactive Waste in Geologic Storage, Fried, S., ed. (American Chemical Society Symposium Series No. 100, 1979).Google Scholar
8. Allard, B. and Beall, G. W. in: Proceedings IAEA/CEC Int. Symp. on the Management of Alpha-Contaminated Wastes (IAEA/CEC, Vienna, 1980).Google Scholar
9. Nowak, E. J., Sandia National Laboratories Report SAND79–1110 (1980).Google Scholar
10. Smith, M. J., Rockwell Hanford Operations Report RHO-BWI-ST-7 (1980).Google Scholar
11. Nowak, E. J. in: Scientific Basis for Nuclear Waste Management, Moore, J. G., ed. (Plenum Press, New York, 1981) pp.545552.Google Scholar
12. Westsik, J. H. Jr., Bray, L. A., Hodges, F. N. and Wheelwright, E. J. in: Scientific Basis for Nuclear Waste Management, Topp, S. V., ed. (North-Holland, New York, 1982)Google Scholar
13. Winslow, C. D., Sandia National Laboratories Report SAND80–2046 (1981).Google Scholar
14. Neretnieks, I., Swedish Nuclear Fuel Safety Project (KBS) Report KBS 30 (1977).Google Scholar
15. Neretnieks, I., Swedish Nuclear Fuel Safety Project (KBS) Report KBS 79 (1978).Google Scholar
16. Nowak, E. J. in: Scientific Basis for Nuclear Waste Management, Northrup, C.J.M. Jr., ed. (Plenum Press, New York, 1980) pp.403410.Google Scholar
17. Pusch, R., Swedish Nuclear Fuel Safety Project (KBS) Report KBS 33 (1977).Google Scholar
18. Beall, G. W. and Allard, B., Trans. Amer. Nuclear Soc. 32, 164 (1979).Google Scholar
19. Beall, G. W. and Allard, B., Nuclear Technology, in press.Google Scholar
20. Schreiner, F., Fried, S. and Friedman, A. M., Nuclear Technology, in press.Google Scholar
21. Eriksen, T., Jacobsson, A. and Pusch, R., Swedish Nuclear Fuel Safety Project Report KBS 81–06 (1981).Google Scholar
22. Torstenfelt, B., Andersson, K., Allard, B. and Olofsson, U. in: Scientific Basis for Nuclear Waste Management, Topp, S. V., ed. (North-Holland, New York, 1982).Google Scholar
23. Eriksen, T. E. and Jacobsson, A., Swedish Nuclear Fuel Safety Project (KBS) Report KBS81–12 (1982).Google Scholar
24. Torstenfelt, B., Kipatsi, H., Andersson, K., Allard, B. and Oloffson, U. in: Scientific Basis for Radioactive Waste Management Proceedings, Fifth International Symposium, Berlin, June 7–10, 1982, to be published.Google Scholar
25. Dosch, R. G., Sandia National Laboratories Report SAND78–0710 (1978).Google Scholar
26. Nowak, E. J., Sandia National Laboratories Report SAND82–0750 (1982).Google Scholar
27. Molecke, M., Sandia National Laboratories, memorandum to distribution, October 8, 1976.Google Scholar
28. Erickson, K. L., Sandia National Laboratories Report SAND81–1095/2 (1981).Google Scholar
29. Crank, J., The Mathematics of Diffusion (Oxford Press, London, 1956) pp.911.Google Scholar
30. Li, Y.-H. and Gregory, S., Geochimica et Cosmochimica Acta 38, 703 (1974).Google Scholar
31. Avogadro, A., Murray, C. N. and DePlano, A. in: Scientific Basis for Nuclear Waste Management, Northrup, C.J.M. Jr., ed. (Plenum Press, New York, 1980) pp.665671.Google Scholar
32. Avogadro, A., Murray, C. N., DePlano, A. and Bidoglio, G. presented in: International Sympsoium on Migration in the Terrestrial Environment of Long-Lived Radionuclides from the Nuclear Fuel Cycle, Knoxville, Tennessee, July 27–31, 1981, IAEA-SM-257/73, to be published.Google Scholar