Michaël Descostes is an expert in hydrogeochemistry, holding a PhD in Geosciences and an Habilitation to Supervise Research (HDR). He leads the Environment R&D Department at Orano Mining and serves as an Associate Researcher at the University of Poitiers and Mines Paris – PSL.
He develops multi-scale approaches combining field observations, laboratory experiments, and reactive transport modelling to understand, quantify, and predict the behaviour of contaminants and radionuclides in both natural and human-impacted environments. His work takes a long-term perspective, aiming to anticipate the evolution of environmental systems over timescales ranging from a few years to several centuries.
His career began at the CEA, with an initial experience in the defence sector focused on environmental monitoring, before moving into civil activities between 1998 and 2009 as a Research Engineer at the Laboratory for Measurement and Modelling of Radionuclide Migration. There, he contributed to landmark studies on deep geological disposal of nuclear waste, radionuclide migration in clayey media, radiolabelled soils, and environmental monitoring systems for contaminated sites. This research was grounded in an integrated approach combining experimentation, in-situ observation, and modelling, addressing core issues of nuclear safety and long-term waste management.
Since 2009, at Orano Mining, he has led environmental R&D activities spanning the entire mining cycle, from exploration to site rehabilitation. His work covers the environmental footprint of uranium mines, the long-term reactivity of mining residues and waste rock, water management in mining contexts, and the development of innovative remediation solutions. His approach integrates multiple scales — from micro-level reaction processes to site and watershed levels — to better understand the complex interactions between the geosphere, hydrosphere, and biosphere.
At the interface between academic research, industry, and societal challenges, he plays an active role in building international scientific collaborations and co-leads the joint M-Cube laboratory (CNRS – University of Poitiers – Orano), dedicated to understanding and predicting contaminant mobility in mining environments.
His work contributes to the production and dissemination of shared scientific knowledge, drawn upon by the scientific community, industrial stakeholders, and regulatory authorities. Through his publications, expert contributions, and engagement with safety authorities, he helps develop frameworks for understanding and decision-making in the sustainable management of impacted environments.
The author of over 100 international scientific publications and several patents, he actively advances knowledge in environmental geochemistry and its translation into real-world applications. His work reflects a commitment to combining scientific excellence, industrial performance, and responsible environmental stewardship — in a context shaped by the challenges of energy transition and environmental accountability.