Microorganisms in salt formations of potential nuclear waste repositories and their interactions with actinides
The safe storage of nuclear waste in deep geological repositories is an important issue in our society. The migration of actinides within the respective host rock and the transport behavior after a possible release from the repository should be well known. Detrimental effects of the radioactive waste on humans and the environment must be avoided over very long time frames. Microorganisms, which are part of the host rock, can survive for long times under extreme conditions. Their presence in the potential host rock is of interest because microbial processes can affect the physical and geochemical conditions (e.g. pH, Eh, release of gases) on site and the microbes can also interact directly with the actinides. The interaction processes depend on the type of microbial population, the actinide, and the geochemical circumstances.
The aim of this groupe is to obtain information about the diversity and activity of microorganisms in rock salt formations suitable for nuclear waste disposal in Germany and to evaluate their role during the migration of actinides in the geo- and biosphere.
- Investigation of the microbial diversity in rock salt suitable as potential host rock for a nuclear waste repository in Germany by molecular-biological analysis (e.g. DNA/RNA extraction, 16S rRNA gene analysis,) as well as enrichment and isolation of halophilic microorganisms
- Characterization of the interaction mechanisms of halophilic microbial isolates with actinides on a molecular level. Molecular characterization of the formed complexes is taking place by applying Time-Resolved Laser-Induced Fluorescence Spectroscopy (TRLFS), and Infrared Spectroscopy (IR). For the localization of the bound actinide on the microbial cells microscopic techniques such as Scanning Electron Microscopy (SEM) in combination with Energy-Dispersive X-ray spectroscopy (EDX) will be used.
- Microbiology In Nuclear waste Disposal (MIND)
- Transformation mechanisms in bentonites as barrier material for nuclear waste repositories (UMB)
|Foto: M. Rietschel|
- Bader, M.; Müller, K.; Foerstendorf, H.; Drobot, B.; Schmidt, M.; Musat, N.; Swanson, J.S.; Reed, D.T.; Stumpf, T.; Cherkouk, A. (2017) "Multistage bioassociation of uranium onto an extremely halophilic archaeon revealed by a unique combination of spectroscopic and microscopic techniques" Journal of Hazardous Materials 327 225-232.
- Lopez-Fernandez, M.; Cherkouk, A.; Vilchez-Vargas, R.; Jauregui, R.; Pieper, D.; Boon, N.; Sanchez-Castro, I.; Merroun, M. L. (2015) "Bacterial diversity in bentonites, engineered barrier for deep geological disposal of radioactive wastes" Microbial Ecology 70 922–935.
- Moll, H.; Lütke, L.; Bachvarova, V.; Cherkouk, A.; Selenska-Pobell, S.; Bernhard, G. (2014) "Interactions of the Mont Terri Opalinus Clay isolate Sporomusa sp. MT-2.99 with curium(III) and europium(III)" Geomicrobiology Journal 31 682-696.