ASNR, the new French Authority established in January 2025 with the fusion of IRSN (Technical Support Organisation) and ASN (Regulator) has released its technical review of the license application submitted by Andra, the French National Agency for Radioactive Waste Management, for the French geological disposal project (Cigéo), relating to its operational safety.
This review has now been published in English:
The Advisory Committee for Waste issues its recommendations on the safety of Cigéo in the operational phase
It addresses:
1. Operational safety approach
2. Assessment of operational safety
3. Assessment of the impact on health and the environment during operation
4. Industrial pilot phase (PhiPil)
The conclusions of the technical review are the following:
Risk management in operation
IRSN considers that the demonstration of risk management during the Cigéo operational phase has reached the level of maturity required at the licence application file stage for most of its components, in particular with regard to internal risks of nuclear origin (risks of criticality, radioactivity dissemination, exposure of workers to ionising radiation, etc.), risks of external aggression linked to flooding, meteorological events, the industrial environment and aircraft crashes, as well as risks of internal aggression associated with fire, internal flooding, handling of waste packages, loss of auxiliaries and co-activity. The waste acceptance specifications and the controls foreseen when packages are received at the facility are generally satisfactory. The design principles and dimensioning approach adopted by Andra for the civil engineering of the surface and underground facilities also meet the level expected at the construction licence application stage. All of these points will need to be consolidated during the next stages of the project, particularly with regard to fire risk management. Similarly, the monitoring provisions for the first structures still need to be specified before they are built. On this basis, and given the overall very low level of estimated radiological consequences, IRSN considers that the design, construction and operating provisions adopted at this stage for the reference configuration are on the whole appropriate for demonstrating the operational safety of the Cigéo surface facilities, underground infrastructure and ILW-LL disposal zone. In addition, the organisational changes initiated by Andra to transition from the design phase to the industrial phase of construction and operation are, in IRSN’s view, likely to strengthen the anticipation of risk management.
The case of the HLW and ILW-LL cells
However, safety has not yet been demonstrated for the HLW cells, nor for the ILW-VLL cells when they are closed, given the uncertainties concerning the feasibility and adequacy of the provisions for managing their internal atmosphere, particularly with regard to explosion-related risks. The information presented does also not make it possible to conclude on the accessibility of this demonstration in the specific case of disposal of bituminous waste packages in their current state. Changes in operating methods or the design of disposal cells may therefore be necessary. 6/7 Consequently, IRSN considers that it is now important to complete and consolidate the assessment of the safety of Cigéo in the operational phase, by taking full advantage of the industrial pilot phase, based in particular on disposal test cells constructed in situ in the underground facility, under environmental and industrial operating conditions that take account of the changes in scale compared with surface tests or those carried out in the underground laboratory. In this respect, a duration for the industrial pilot phase of around thirty years from the issue of the Licensing Decree, as currently planned by Andra, seems reasonable to gather the necessary complements and confirm the facility’s ability to operate safely.
Cigéo’s flexibility and adaptability
In addition, IRSN emphasizes that the flexibility of the facility, which is a fundamental issue in its deployment in order to preserve the capacity for safe management of the HL and IL-LL waste from the reference inventory, must be supported by concrete organisational and material provisions. Finally, based on the preliminary operational safety analysis presented by Andra as part of the studies on the adaptability of Cigéo to the reserve inventory waste, IRSN does not identify any redhibitory issue relating to the safe disposal of spent fuel and LL-LL waste included in this reserve inventory waste. This technical review will be supplemented by that of the post-closure safety demonstration as part of the GP3 review.