Impact of microbial activity on the radioactive waste disposal: long term prediction of biocorrosion processes
Résumé
This study emphasizes different experimental approaches and provides perspectives to apprehend biocorrosion
phenomena in the specific disposal environment by investigating microbial activity with regard to the
modification of corrosion rate, which in turn can have an impact on the safety of radioactive waste geological
disposal.
It is found that iron-reducing bacteria are able to use corrosion products such as iron oxides and “dihydrogen” as
new energy sources, especially in the disposal environment which contains low amounts of organic matter.
Moreover, in the case of sulphate-reducing bacteria, the results show that mixed aerobic and anaerobic
conditions are the most hazardous for stainless steel materials, a situation which is likely to occur in the early
stage of a geological disposal. Finally, an integrated methodological approach is applied to validate the
understanding of the complex processes and to design experiments aiming at the acquisition of kinetic data
used in long term predictive modelling of biocorrosion processes.