France Authorizes CEA to Dismantle the Pégase Research Reactor Facility at Cadarache

The French Official Journal published a decree on August 23 authorizing the French Alternative Energies and Atomic Energy Commission (CEA) to carry out dismantling operations on the Pégase (Pégase) nuclear facility located at the Cadarache site in Saint-Paul-lès-Durance, Bouches-du-Rhône department. The facility is classified as Basic Nuclear Installation No. 22 (INB 22). The decree specifies the implementation phases for the partial dismantling of the Pégase research reactor and authorizes the CEA to build the equipment required for the dismantling operations.

Under the decree, the boundaries of the Pégase facility will be adjusted to provide the necessary space for the layout of dismantling equipment and the temporary storage of waste generated during the dismantling process. The dismantling scope covers the Pégase facility itself, including the main building housing the storage and treatment areas, the building housing the control room, the water treatment building, the ventilation building, and the air-cooled condensers.

The decree states that the primary reason for dismantling the Pégase main building is its insufficient seismic resistance. Before entering the main dismantling phase, the CEA must submit a dismantling preparation report to the minister responsible for nuclear safety and to the French Nuclear Safety and Radiation Protection Authority (ASNR), and must inform the Cadarache Local Information Committee of project progress at least once a year.

According to public information, the public inquiry concerning the dismantling of the INB 22 Pégase facility was held from March 17 to April 17, 2025. The Pégase research reactor was commissioned in 1964 and, after approximately ten years of operation, was converted from 1980 onward into a radioactive material storage facility, including storage uses related to spent fuel.

INB 22 consists of two separate facilities: in addition to Pégase, it includes the CASCAD spent fuel dry storage facility. In its 2024 report, ASNR mentioned that the dismantling of the Pégase reactor is scheduled for completion in 2065.