Context and research themes

The LETIS has the following missions:

 
• Defining and implementing research programs in the field of safety concerning the storage of waste in geological formations. These programs, which include the acquisition of experimental data, modeling, and the confirmation of methods, aim in particular to:

 
1. Evaluate the natural containment properties of clay formations based on their characterization and an understanding of the mechanisms affecting transfers in these environments,
 
2. Evaluate the thermal, hydric and mechanical perturbations likely to occur in a storage facility, and their effects on the containment properties,
 
3. Specify the influence of chemical processes on the containment performance of the barriers making up a storage facility by studying the mechanisms of interaction between materials, in particular.

 
• The coordination and running of experiments performed in this context at the Tournemire experimental facility and the maintenance and implementation of logistical resources at this facility.
 
• The contribution to the assessment, for which the IRSN is responsible, of files concerning the safety of geological storage facilities with respect to hydro-geochemistry, the transfer of radionuclides in geological formations, hydrodynamics, geotechnics and geomechanics.
 
• The definition and implementation of research programs intended to improve the understanding and modeling capabilities of transport and retention of radionuclides in non-saturated areas of soil and in groundwater.
  

In addition to the missions described above, the LETIS gives any necessary support to the activities of other IRSN units in the field of geochemistry and mechanisms for the transfer and retention of radionuclides in soils and subsoils.

Specialties and researchers

Facilities and techniques

• The Tournemire experimental platform, in which several boreholes have been equipped, to develop the laboratory’s capabilities in hydro-geochemical characterization and the understanding of transport phenomena in an indurated clay medium.

• The Chernobyl experimental platform, located 2 km from the reactor where the accident occurred, allows ‘life-sized’ research into the migration of radionuclides in a saturated and unsaturated medium and the development of the laboratory’s site characterization capability (hydro-geological and radiological) and modeling capability.
  

Partnership and research networks

• Partner of the TRASSE national research group
• Participants in the Mont Terri international project (Switzerland)
• Ukrainian institutes: UIAR and IGS  
• Ecole des Mines, Paris
• Universities: Paris VI, Paris XI, Poitiers, Nimes, Orléans, Montpellier, Bordeaux... 
• National Polytechnic Institute, Toulouse 
• National natural history museum 
• EDF