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Laboratory scale advection-matrix diffusion experiment in Olkiluoto veined gneiss using H-3 and Cl-36 as tracers

Published online by Cambridge University Press:  05 January 2017

Mikko Voutilainen ,
Pekka Kekäläinen ,
Jukka Kuva ,
Marja Siitari-Kauppi ,
Maarit Yli-Kaila  and
Lasse Koskinen
Mikko Voutilainen*
Affiliation:
Department of Chemistry, University of Helsinki, 00014, Helsinki, Finland.
Pekka Kekäläinen
Affiliation:
Department of Chemistry, University of Helsinki, 00014, Helsinki, Finland.
Jukka Kuva
Affiliation:
Department of Chemistry, University of Helsinki, 00014, Helsinki, Finland. Department of Physics, University of Jyväskylä, 40014, Jyväskylä, Finland.
Marja Siitari-Kauppi
Affiliation:
Department of Chemistry, University of Helsinki, 00014, Helsinki, Finland.
Maarit Yli-Kaila
Affiliation:
Posiva oy, Olkiluoto, 27160, Eurajoki, Finland.
Lasse Koskinen
Affiliation:
Posiva oy, Olkiluoto, 27160, Eurajoki, Finland.
*
*(Email: [email protected])
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Abstract

Spent nuclear fuel from Finnish power plants is planned to be deposited deep in the crystalline bedrock. The bedrock needs to be well characterized to properly assess the risks inherent to the long term safety of the site. In the bedrock the possibly released radionuclides are assumed to be mainly transported by water conducting fractures and their transport is retarded by matrix diffusion and sorption. In this work transport properties of an 80 centimeters long veined gneiss drill core sample from Olkiluoto was studied using an advection-matrix diffusion experiment, which was developed to demonstrate the effect of rock matrix for transport of radionuclides in an advective fracture. The experiment was performed using H-3 and Cl-36 as tracers, and effective diffusion coefficients (De) of (1.7 ± 0.7) × 10-13 m2/s and (1.4 ± 1.0) × 10-14 m2/s and porosities of 1.1 ± 0.3 % and 0.23 ± 0.10 % were determined, respectively. A lower porosity and De for Cl-36 than for H-3 indicates an effect of anion exclusion and the results were found to be in agreement with previous laboratory experiments. However, the comparison to results from a similar in-situ experiment showed that the transport of H-3 and Cl-36 is retarded more in laboratory than in in-situ conditions by matrix diffusion.

Keywords

diffusionporositynuclear materials
Type
Articles
Information
MRS Advances , Volume 2 , Issue 12: Scientific Basis for Nuclear Waste Management XL , 2017 , pp. 655 - 660
Copyright
Copyright © Materials Research Society 2017 

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References

REFERENCES

Voutilainen, M., Poteri, A., Helariutta, K., Siitari-Kauppi, M., Nilsson, K., Andersson, P., Byegård, J., Skålberg, M., Kekäläinen, P., Timonen, J., Lindberg, A., Pitkänen, P., Kemppainen, K., Liimatainen, J., Hautojärvi, A., Koskinen, L., WM2014 Conference proceedings, 14258 (2014).Google Scholar
Vilks, P., Cramer, J. J., Jensen, M., Miller, N. H., Miller, H. G., Stanchell, F. W., J. Contam Hydrol. 61(1-4), 191–202 (2003).Google Scholar
Cvetkovic, V., Cheng, H., Widestrand, H., Byegård, J., Winberg, A., Andersson, P., Water Resour. Res. 43, W11421 (2007).Google Scholar
Soler, J. M., Landa, J., Havlova, V., Tachi, Y., Ebina, T., Sardini, P., Siitari-Kauppi, M., Eikenberg, J., Martin, A. J., J. Contam. Hydrol. 179, 89–101 (2015).Google Scholar
Kuva, J., Voutilainen, M., Kekäläinen, P., Siitari-Kauppi, M., Sammaljärvi, J., Timonen, J., and Koskinen, L., Transp. Porous Med. 115, 1–20 (2016).Google Scholar
Sammaljärvi, J., Lindberg, A., Ikonen, J., Voutilainen, M., Siitari-Kauppi, M., Koskinen, L. in Scientific Basis for Nuclear Waste Management XXXVII, edited by Duro, L., Giménez, J., Casas, I. and de Pablo, J., (Mater. Res. Soc. Symp. Proc. 1665, Pittsburgh, PA, 2014) pp. 31–37.Google Scholar
Voutilainen, M., Ikonen, J., Sammaljärvi, J., Kuva, J., Lindberg, A., Siitari-Kauppi, M., and Koskinen, L., in Scientific Basis for Nuclear Waste Management XXXIX, (2016) (in press).Google Scholar
Kuva, J., Voutilainen, M., Kekäläinen, P., Siitari-Kauppi, M., Timonen, J., and Koskinen, L., Transp. Porous Med. 107, 187–204 (2015).Google Scholar
Kekäläinen, P., AIP Conf. Proc. 1618, 513–516 (2014).Google Scholar
Poteri, A., Nilsson, K., Andersson, P., Siitari-Kauppi, M., Helariutta, K., Voutilainen, M., Kekäläinen, P., Ikonen, J., Sammaljärvi, J., Lindberg, A., Byegård, J., Skålberg, M., Kuva, J., The first matrix diffusion experiment in the water phase of the REPRO project, (in press).Google Scholar