Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-25T17:58:59.631Z Has data issue: false hasContentIssue false
  • English
  • Français

Modelling in-situ Matrix Diffusion at Palmottu Natural Analogue Study Site in SW Finland.

Published online by Cambridge University Press:  01 January 1992

Karl Rasilainen  and
Juhani Suksi
Karl Rasilainen
Affiliation:
Technical Research Centre of Finland, Nuclear Engineering Laboratory, P.O. Box 208, SF-02151 Espoo, Finland
Juhani Suksi
Affiliation:
University of Helsinki, Department of Radiochemistry, SF-00170 Helsinki, Finland
Get access

Abstract

Radioactive disequilibria, between U-238, U-234, and Th-230, in crystalline rock adjacent to a fracture, indicates mass transfer of U and Th between water in the fracture and the rock. The matrix diffusion theory was used to interpret the observed profiles of mobilized nuclides around the natural fracture. The interpretation of the profiles was based on the use of uranium series disequilibrium code, URSE, and migration code FTRANS. The model system was characterized using all available site-specific data, and the system evolution was outlined using the geology of the Palmottu site. The simulated concentration profiles, as a function of depth from the fracture surface, indicate that measured profiles can be modelled by matrix diffusion, assuming realistic initial and boundary conditions and diffusion times of 300,000 years.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 294: Symposium V – Scientific Basis for Nuclear Waste Management XVI , 1992 , 489
Copyright
Copyright © Materials Research Society 1993

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.)

References

REFERENCES

1. Suksi, J., Ahonen, L., and Niini, H. (eds.), “The Palmottu Analogue Project.” Progress Report 1991, Geological Survey of Finland 1992, Report YST-78, 138 pp.Google Scholar
2. Suksi, J., Ruskeeniemi, T., Lindberg, A., and Jaakkola, T., “The distribution of natural radionuclides on fracture surfaces in Palmottu analogue study site in SW Finland”. Radiochim. Acta 52/53, pp. 367–372 (1991).Google Scholar
3. Suksi, J., Ruskeeniemi, T., and Rasilainen, K., “Matrix Diffusion - Evidences from Natural Analogue Studies at Palmottu in SW Finland”, Radiochimica Acta 1992 (in press).Google Scholar
4. Parkhomenko, E. I., Electrical Properties of Rocks, Plenum Press, New York 1967, p. 277.Google Scholar
5. Rasilainen, K., and Suksi, J., “On the Quantitative Interpretation of Uranium Series Disequilibria” (in Finnish, English Abstract), Research Notes 1404, Technical Research Centre of Finland 1992, 63 pp. + app. 14 p.Google Scholar
6. INTERA Environmental Consultants Inc., “FTRANS: A Two-dimensional Code for Simulating Fluid Flow and Transport of Radioactive Nuclides in Fractured Rock for Repository Performance Assessments”, Technical Report ONWI-426, Office of Nuclear Waste Isolation, 1983, 202 pp.Google Scholar
7. Eronen, M., and Olander, H., “On the World's Ice Ages and Changing Environments”, Report YJT-90-13, Nuclear Waste Commission of Finnish Power Companies, 1990, 72 PP.Google Scholar
8. Ohnuki, T., Watanabe, S., and Murakami, T., “Study on the Role of 23” Th in Uranium Series Nuclides Migration". Proc. Symposium on Scientific Basis for Nuclear Waste Management XII, (Mat. Res. Soc. Symp. Proc. Vol. 212, Pittsburgh, 1991) pp. 733-740.Google Scholar
9. Ames, L.L., McGarrah, J.E. and Walker, B.A., “Sorption of trace constituents from aqueous solutions onto secondary minerals”. I Uranium. Clays and Clay minerals, Vol. 31, No. 5, pp. 321-334. (1983).Google Scholar
10. Ivanovich, M., Longworth, G., Wilkins, M.A., Hasler, S.E. and Lloyd, M.J., “Measurement of effective Kd factors for the long term uranium and thorium isotopes in samples of London clay (Bradwell) and mudrock (Fulbeck)”, Report NSS/R1 17. Nirex 1988.Google Scholar
11. Hakanen, M., and Hölttä, P., “Review of Sorption and Diffusion Parameters for TVO-92”, Report YJT-92-14, Nuclear Waste Commission of Finnish Power Companies, 1992. 62 pp. + app. 17 p.Google Scholar