Speaker
Dr
Mikko Voutilainen
(Department of Chemistry, University of Helsinki, Finland)
Description
In Finland and Sweden KBS-3 concept has been chosen for disposal of spent nuclear fuel in crystalline rock. Recent transport experiments have shown that heterogeneity of rock may play a major role in transport of radionuclides. Autoradiographic methods has been proven to be able to assist the characterization of heterogeneous structures. In this study we tested a novel digital autoradiographic device called Beaver$^{TM}$ which applies a Micro Patterned Gaseous Detector in order to quantitatively map beta emissions by C-14 atoms. The studied samples were impregnated with C-14 labelled MMA (Methyl MethAcrylate) and polymerized to PMMA using heat. The Beaver$^{TM}$ was then used to determine concentration of C-14 atoms which can then be converted to porosity based on the amount of C-14 intruded into the rock sample. The resulting images show a heterogeneous distribution of porosity which arises from the different porosities of minerals. The samples were chosen from three sites that has been used recently in *in situ* diffusion experiments: Olkiluoto (Finland), Äspö (Sweden) and Grimsel (Switzerland).
Primary author
Dr
Mikko Voutilainen
(Department of Chemistry, University of Helsinki, Finland)
Co-authors
Mr
Juuso Sammaljärvi
(Department of Chemsistry, University of Helsinki, Finland)
Jérôme Donnard
(AI4R SAS, Nantes, France)
Dr
Marja Siitari-Kauppi
(Department of Chemistry, University of Helsinki, Finland)
Samuel Duval
(AI4R SAS, Nantes, France)
