* Identify sources of natural and artificial radionuclides affecting the marine environment (Celtic Sea, Bay of Biscay, Channel and Seine estuary, North Sea, Mediterranean Sea, Gulf of Lions, and Rhone delta).
* Study spatio-temporal changes in radioactivity in seas, coastal areas, and estuaries close to or far from industrial sites.
* Study physical, chemical, and biological mechanisms affecting the behavior of natural or artificial radionuclides to explain and predict their transfer to the environment.
* Provide the necessary data for modeling the impact of nuclear facilities (dilution factors, CF, Kd values, etc.).
* Publish results and transmit information to the scientific community, supervisory authorities, the media, and the public.
The program includes all the necessary operations for taking and preparing radionuclide samples and measuring them.
· ensuring the sustainability of environmental radioactivity observatories set up along the Mediterranean, Atlantic, and Channel coasts.
· studying radionuclide sources and how they are distributed among the different environmental components – seawater, sediments, organisms; gaining insight into radionuclide reactivity with particles in the Channel and the Rhone delta; explaining how radionuclides are transferred to bioindicators in the La Hague coastal ecosystem,
· explaining deposits and movements of radionuclides fixed to sediments at the mouth of the Rhone and in the Channel; studying the distribution of elements into the dissolved, colloidal, and particulate phases in the Rhone and its area of influence, as a function of salinity.