A long-running in situ experiment in clay: 12 years of the Bitumen–Nitrate–Clay interaction experiment at Mont Terri rock laboratory

Abstract 3 is the most prevalent. NaNO3, along with radionuclides immobilised in the bitumen matrix, will slowly dissolve and leach out into the surrounding host rock. The transport and reactivity of nitrate in a deep clay formation, in the presence and absence of electron donors coming from bituminised waste (i.e. acetate, H2), has been studied extensively inside anoxic and water-saturated chambers in the clay in the Bitumen–Nitrate–Clay interaction (BN) experiment. This in situ experiment in Opalinus clay is located in the Mont Terri rock laboratory (Switzerland). The effect of a nitrate plume on redox-sensitive radionuclides is also studied with stable selenium in selenate form as a proxy for 79 Se, an important fission product for the long-term dose to humans. 2) boosted the microbial activity and nitrate reduction rate. From 2019 until now, injection tests with selenate, with and without nitrate, have been performed. These tests showed clearly that the presence of nitrate, a stronger oxidiser, inhibited the microbial reduction of selenate. In the absence of nitrate, the microbial population was able to reduce selenate to selenite and more reduced Se species. The results obtained in this in situ experiment will be summarised in this work, addressing questions concerning the effect of biogeochemical perturbations of the clay on the migration of redox-sensitive radionuclides.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: A long-running in situ experiment in clay: 12 years of the Bitumen–Nitrate–Clay interaction experiment at Mont Terri rock laboratory ; volume:2 ; year:2023 ; pages:145-146 ; extent:2 ; Safety of nuclear waste disposal ; 2 (2023), 145-146 (gesamt 2)

Contributors, Places and Time

• Creator: Hendrix, Katrien ; Bleyen, Nele ; Mijnendonckx, Kristel ; Van Gompel, Veerle ; Albrecht, Achim ; Linard, Yannick ; De Cannière, Pierre ; Surkova, Maryna ; Wittebroodt, Charles ; Small, Joe ; Weyand, Torben ; Jendras, Michael ; Valcke, Elie

Further information

• DOI: 10.5194/sand-2-145-2023
• URN: urn:nbn:de:101:1-2023090704180112444360
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 14.08.2025, 11:01 AM CEST