caa a22 4500 378927280 CHVBK 20180305123620.0 cr unu---uuuuu 161128e20041101xx s 000 0 eng 10.1524/ract.92.9.757.54988 doi (NATIONALLICENCE)gruyter-10.1524/ract.92.9.757.54988 In-situ diffusion of HTO, 22Na+, Cs+ and I- in Opalinus Clay at the Mont Terri underground rock laboratory [Elektronische Daten] [Luc R. Van Loon, P. Wersin, J. M. Soler, J. Eikenberg, Th. Gimmi, P. Hernán, S. Dewonck, S. Savoye] The diffusion properties of the Opalinus Clay were studied in the underground research laboratory at Mont Terri (Canton Jura, Switzerland) and the results were compared with diffusion data measured in the laboratory on small-scale samples. The diffusion of HTO, 22Na+, Cs+ and I- were investigated for a period of 10months. The diffusion equipment used in the field experiment was designed in such a way that a solution of tracers was circulated through a sintered metal screen placed at the end of a borehole drilled in the formation. The concentration decrease caused by the diffusion of tracers into the rock could be followed with time and allowed first estimations of the effective diffusion coefficient. After 10months, the diffusion zone was overcored and the tracer profiles measured. From these profiles, effective diffusion coefficients and rock capacity factors could be extracted by applying a two-dimensional transport model including diffusion and sorption. The simulations were done with the reactive transport code CRUNCH. In addition, results obtained from through-diffusion experiments on small-sized samples with HTO, 36Cl- and 22Na+ are presented and compared with the in situ data. In all cases, excellent agreement between the two data sets exists. Results for Cs+ indicated five times higher diffusion rates relative to HTO. Corresponding laboratory diffusion measurements are still lacking. However, our Cs+ data are in qualitative agreement with through-diffusion data for Callovo-Oxfordian argillite rock samples, which also indicate significantly higher effective diffusivities for Cs+ relative to HTO. © 2004 Oldenbourg Wissenschaftsverlag GmbH Laboratory techniques, experiments nationallicence Analytical chemistry nationallicence Inorganic chemistry nationallicence Van Loon Luc R. aut Wersin P. aut Soler J. M. aut Eikenberg J. aut Gimmi Th aut Hernán P. aut Dewonck S. aut Savoye S. aut Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 757-763 0033-8230 92:9-11/2004<757 2004 92 ract https://doi.org/10.1524/ract.92.9.757.54988 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/ract.92.9.757.54988 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Van Loon Luc R. aut NATIONALLICENCE 700 1- Wersin P. aut NATIONALLICENCE 700 1- Soler J. M. aut NATIONALLICENCE 700 1- Eikenberg J. aut NATIONALLICENCE 700 1- Gimmi Th aut NATIONALLICENCE 700 1- Hernán P. aut NATIONALLICENCE 700 1- Dewonck S. aut NATIONALLICENCE 700 1- Savoye S. aut NATIONALLICENCE 773 0- Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 757-763 0033-8230 92:9-11/2004<757 2004 92 ract CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence SWISSBIB 334512670 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter