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Soler, J. M.*; Kek
linen, P.*; Pulkkanen, V.-M.*; Moreno, L.*; Iraola, A.*; Trinchero, P.*; Hokr, M.*; 
ha, J.*; Havlov
, V.*; Trpko
ov, D.*; et al.
Nuclear Technology, 209(11), p.1765 - 1784, 2023/11
Times Cited Count：2 Percentile：72.91(Nuclear Science & Technology)Soler, J. M.*; Neretnieks, I.*; Moreno, L.*; Liu, L.*; Meng, S.*; Svensson, U.*; Iraola, A.*; Ebrahimi, K.*; Trinchero, P.*; Molinero, J.*; et al.
Nuclear Technology, 208(6), p.1059 - 1073, 2022/06
Times Cited Count：4 Percentile：45.99(Nuclear Science & Technology)The SKB Task Force is an international forum on modelling of groundwater flow and solute transport in fractured rock. The WPDE experiments are matrix diffusion experiments in gneiss performed at the ONKALO underground facility in Finland. Synthetic groundwater containing several conservative and sorbing tracers was injected along a borehole interval. The objective of Task 9A was the predictive modelling of the tracer breakthrough curves from the WPDE experiments. Several teams, using different modelling approaches and codes, participated in this exercise. An important conclusion from this exercise is that the modelling results were very sensitive to the magnitude of dispersion in the borehole opening, which is related to the flow of water. Focusing on the tails of the breakthrough curves, which are more directly related to matrix diffusion and sorption, the results from the different teams were more comparable.
Soler, J. M.*; Keklinen, P.*; Pulkkanen, V.-M.*; Moreno, L.*; Iraola, A.*; Trinchero, P.*; Hokr, M.*; ha, J.*; Havlov, V.*; Trpkoov, D.*; et al.
SKB TR-21-09, 204 Pages, 2021/11
Soler, J. M.*; Neretnieks, I.*; Moreno, L.*; Liu, L.*; Meng, S.*; Svensson, U.*; Trinchero, P.*; Iraola, A.*; Ebrahimi, H.*; Molinero, J.*; et al.
SKB R-17-10, 153 Pages, 2019/01
The SKB Task Force is an international forum on modeling of groundwater flow and solute transport in fractured rock. The WPDE experiments are matrix diffusion experiments in gneiss performed at the ONKALO underground facility in Finland. Synthetic groundwater containing several conservative and sorbing tracers was injected along a borehole interval. The objective of Task 9A was the predictive modeling of the tracer breakthrough curves from the WPDE experiments. Several teams, using different modelling approaches, participated in this exercise. An important conclusion from this exercise is that the modeling results were very sensitive to the magnitude of dispersion in the borehole opening, which is related to the flow of water. Focusing on the tails of the breakthrough curves, which are more directly related to matrix diffusion and sorption, the results from the different teams were more comparable. The modeling results have also been finally compared to the measured breakthroughs.
Soler, J. M.*; Landa, J.*; Havlov, V.*; Tachi, Yukio; Ebina, Takanori*; Sardini, P.*; Siitari-Kauppi, M.*; Eikenberg, J.*; Martin, A. J.*
Journal of Contaminant Hydrology, 179, p.89 - 101, 2015/08
Times Cited Count：39 Percentile：81.5(Environmental Sciences)Matrix diffusion is a key process for radionuclide retention in crystalline rocks. An in-situ diffusion experiment in granite matrix was performed at the Grimsel Test Site (Switzerland). Several tracers (HTO, Na
, Cs) were circulated through a borehole and the decrease in tracer concentrations was monitored for 2.5 years. Then, the borehole section was overcored and the tracer profiles in the rock were analyzed. Transport distances in the rock were 20 cm for HTO, 10 cm for Na and 1 cm for Cs. The dataset was analyzed with diffusion-sorption models by different teams using different codes, with the goal of obtaining effective diffusivities (De) and rock capacity factors. There was a rather good agreement between the values from different teams, implied that De and capacity factors in the borehole damaged zone are larger than those in the bulk rock. However, HTO seems to display large discrepancies between measured and modeled results.
Soler, J. M.*; Landa, J.*; Havlov, V.*; Tachi, Yukio; Ebina, Takanori*; Sardini, P.*; Siitari-Kauppi, M.*; Martin, A. J.*
Materials Research Society Symposium Proceedings, Vol.1665, p.85 - 91, 2014/09
Matrix diffusion is a key process for radionuclide retention in crystalline rocks. An in-situ diffusion experiment in granite matrix was performed at the Grimsel Test Site (Switzerland). Several tracers (HTO, Na, Cs) were circulated through a borehole and the decrease in tracer concentrations was monitored for 2.5 years. Then, the borehole section was overcored and the tracer profiles in the rock were analyzed. Transport distances in the rock were 20 cm for HTO, 10 cm for Na and 1 cm for Cs. The dataset was analyzed with diffusion-sorption models by different teams using different codes, with the goal of obtaining effective diffusivities (
e) and rock capacity factors. There was a rather good agreement between the values from different teams, implied that e and capacity factors in the borehole damaged zone are larger than those in the bulk rock. However, HTO seems to display large discrepancies between measured and modeled results, which have to be investigated in more detail.
Soler, J. M.*; Landa, J.*; Havlov, V.*; Tachi, Yukio; Ebina, Takanori*; Sardini, P.*; Siitari-Kauppi, M.*; Martin, A.*
Nagra NAB 12-53, 80 Pages, 2013/02
An in-situ long-term diffusion (LTD) experiment was performed at the Grimsel Test Site (Switzerland). Tracers, HTO, 
Na, 
Cs, were continuously circulated through a packed-off borehole and the tracer concentrations in the solution was monitored for 2.5 years. Subsequently, the borehole section was overcored and the tracer profiles in the rock analyzed. The drop in activity for Cs in the solution was much pronounced. Transport distances were about 20 cm for HTO, 10 cm for Na and 1 cm for Cs. The dataset was analyzed with diffusion-sorption models by different teams using different codes, with the goal of obtaining effective diffusion coefficients (
) and rock capacity (
) values. There was a rather good agreement between the values from different teams, implied that and values in the BDZ are larger than those in the bulk rock. However, HTO seems to display large discrepancies between measured and modeled results, which have to be investigated in more detail.
M
ri, A.*; Soler, P.*; Ota, Kunio; Havlov, V.*
Nagra NAB 07-42, 31 Pages, 2007/12
The Long-Term Diffusion (LTD) project, an integral part of Phase IV at the Grimsel Test Site, Switzerland, is an international cooperative project (HYRL, Finland; JAEA and AIST, Japan; NRI/RAWRA, Czech Republic; Nagra, Switzerland) and consists of a series of experiments which aims to obtain quantitative information on matrix diffusion under in situ conditions. The LTD is divided into four work packages, WP1-4. The in situ monopole diffusion experiment (WP1) is preceded by predictive modelling exercise to support the design of the in situ experiment and to increase confidence in the modelling of long-term and large-scale diffusion process by comparing the predictions with the experimental results. This report presents a short overview of the conceptual models and codes applied and the predicted tracer profiles in the rock matrix as well as the expected tracer concentration in the injection solution.
Marin, A.*; Siitari-Kauppi, M.*; Havlov, V.*; Tachi, Yukio; Miksova, J.*
no journal, ,
Matrix diffusion is very important in the context of the performance assessment of radioactive waste repository in the crystalline rocks. An in-situ long-term diffusion (LTD) project has been performed at the Grimsel Test Site, Switzerland, to realistically evaluate matrix diffusion of radionuclides in crystalline rock with minimal disturbance to in-situ conditions. As part of phase-I, tracers, HTO, Na-22, Cs-134, were continuously circulated through a packed-off borehole and the tracer concentrations in the solution was monitored for 2.5 years. Subsequently, the borehole section was overcored and the tracer profiles in the rock analyzed. These results were analyzed with diffusion-sorption models by different teams. The phase-II plans including experimental design and tracers selection will be discussed.
H, Na and Cs diffusion in crystalline rock under real deep geological repository conditionsHavlov, V.*; Martin, A. J.*; Siitari-Kauppi, M.*; Tachi, Yukio
no journal, ,
The Long Term Diffusion Project (LTD) is an international project consisting of a series of experiments that aim was to obtain quantitative information on matrix diffusion under in situ conditions. In the 1st in-situ diffusion experiment, radionuclides (H, Na, Cs) were injected into the borehole in undisturbed rock matrix in Grimsel test site. The activity decrease was observed by regular sampling of the experimental solution in the system. After 800 days, the system was closed and the borehole was overcored. The active rock, surrounding the experimental interval, was then sawed and the tracer profiles were measured in the rock samples in order to determine the diffusion extent. Non sorbing H migrated up to 17 cm into the rock matrix. Na as slightly sorbing tracer migrated up to 7 cm. Finally, sorbing Cs migrated surprisingly up to 1.5 cm, instead expected several mms. The analyses results were afterwards used as a base for post mortem modelling.
Soler, J. M.*; Martin, A. J.*; Lanyon, G. W.*; Havlov, V.*; Siitari-Kauppi, M.*; Tachi, Yukio
no journal, ,
An in-situ long-term diffusion (LTD) project has been performed at the Grimsel Test Site, Switzerland, to realistically evaluate matrix diffusion of radionuclides in crystalline rock with minimal disturbance to in-situ conditions. A second in situ diffusion experiment (monopole 2) has been performed. Predictive calculations for the monopole-2 experiment, based on results from monopole 1 or from through-diffusion experiments have been compared to monitoring data from the injection and observation boreholes. For the non-sorbing tracers (HTO, 
Cl
), the diffusion parameters from the through-diffusion experiments provide a better match for the measurements, especially in the injection borehole. The initial drop in activities for Cs and 
Ba
shows clearly the effect of sorption. Bulk rock parameters for Cs from monopole 1 seem to be applicable to monopole 2. However, Ba seems to sorb more strongly than expected.
Soler, J. M.*; Lfgren, M.*; Nilsson, K.*; Lanyon, G. W.*; Gylling, B.*; Vidstrand, P.*; Neretnieks, I.*; Moreno, L.*; Liu, L.*; Meng, S.*; et al.
no journal, ,
The GWFTS Task Force is an international forum in the area of modeling of groundwater flow and solute transport in fractured rock. The WPDE experiments are matrix diffusion experiments in gneiss performed at the ONKALO underground facility in Finland. Synthetic groundwater containing several conservative and sorbing radiotracers was injected along a borehole interval. The objective of Task 9A of Task Force was the predictive modeling of the tracer breakthrough curves from the WPDE experiments. Several teams, using different modeling approaches, participated in this exercise. An important conclusion from this exercise is that the modeling results were very sensitive to the magnitude of dispersion in the borehole opening, which is related to the flow of water. Focusing on the tails of the breakthrough curves, which are more directly related to matrix diffusion and sorption, the results from the different teams were more comparable.
Martin, A.*; Fukatsu, Yuta; Tachi, Yukio; Ishida, Keisuke*; Muuri, E.*; Siitari-Kauppi, M.*; Havlov, V.*; Vokal, A.*
no journal, ,
Havlov, V.*; Zuna, M.*; Brzda, L.*; Rosendorf, T.*; Sammaljrvi, J.*; Nenonen, V.*; Siitari-Kauppi, M.*; Sasao, Eiji; Gvo
dk, L.*
no journal, ,
Anion exclusion is a process that has been widely observed mainly with concern to clay materials. However, this process has also been observed in some types of crystalline rock. Because anion exclusion exerts the impact on migration in the most constricted parts of nanometre-scale pores, this study focused on H, Cl and 
I diffusion together with the characterisation of the rock pore structure of magmatic and metamorphic rocks. Both the anionic species exhibited lower diffusion coefficients than that of H, thus indicating anionic exclusion mainly in the metamorphic rocks studied. The De values for the anions in the metamorphic rocks differed from those in the magmatic rocks by around one order of magnitude. The difference between the De values for magmatic and metamorphic rocks is clearly supported by pore structure visualisation by autoradiography. Preliminary results showed decreasing accessible porosity for anionic species rather than decreasing pore diffusion coefficients.
