Secure financing of long-term nuclear costs: ASN issues its opinion on the licensees’ reports

Published on 16/09/2020 at 13:12

Information notice

At the request of the General Directorate for Energy and the Climate (DGEC) in 2019, ASN has issued its opinion on the fifth three-yearly reports submitted by the nuclear licensees with respect to the secure financing of long-term nuclear costs. This evaluation and provisioning system aims to ensure that the costs of decommissioning and of spent fuel and radioactive waste management are evaluated with sufficient prudence and are covered by dedicated assets so that the necessary financial resources will be available when the time comes.

ASN examined the technical hypotheses underpinning these cost evaluations.

The main ASN observations were, generally speaking, as follows:

  • The scope of evaluation of the costs identified by the licensees remains incomplete. This scope in fact excludes operations with high financial stakes, such as the preparatory operations for decommissioning, the characterisation and management of soil and structural pollution, complete clean-out operations, the cost of works to maintain the facilities over their entire lifetime.
  • The hypotheses adopted for the evaluation of the complete costs need to be reassessed, so that they are more realistic and prudent, with regard to the planning of decommissioning projects and programmes (inclusion of the risks of projects being delayed, inter-dependence between projects liable to amplify these delays) and the risks linked to the unavailability of storage, processing and disposal facilities. 
  • The cost forecasts at completion of the projects must be more detailed and better justified, in the light of the observed progress of the projects: delays, which are particularly frequent when it comes to decommissioning, increase these costs at completion accordingly.
  • With regard to radioactive materials and waste management, the evaluation hypotheses proposed by the licensees are not prudent enough: they do not systematically include legacy waste disposal management, nor uncertainties surrounding the management of LLW-LL waste; they overestimate the prospects for the reuse of certain materials and underestimate the work needed with regard to bituminous waste; the availability of future waste disposal facilities has not yet been sufficiently taken into account.

For each of the licensees, the main conclusions of the assessment conducted by ASN are as follows:


  • Andra’s fifth three-yearly report is concise but its content is nonetheless sufficient.


  • ASN favourably considers the detailed report produced, plus its technical progress sheets project by project.
  • However, the impossibility of comparing provisions transferred from one year to another hampers the transparency of the evaluation.
  • Some hypotheses are insufficiently prudent, notably those concerning:
    • the possibility of reprocessing the majority of the spent fuel,
    • the failure to take into account contingencies regarding the unavailability of the facilities and means required for the decommissioning and legacy waste retrieval and conditioning programmes,
    • the risk of an interruption in the circuit in the event of a problem affecting the scheduled transport programme.

Cyclife France

  • The duration of decommissioning of the Centraco facility and the soil and structural clean-out costs are based on hypotheses that need to be consolidated and clarified, given ASN doctrine in this field.


  • The financing of long-duration storage costs for the waste resulting from the reprocessing of spent fuel on the La Hague site is now secure, which constitutes real progress; moreover, the presentation in the three-yearly report of the main project risks is a step forwards in terms of transparency.
  • Transparency efforts must be continued to clarify the design-basis hypotheses of the complete costs thus evaluated and the main risks, notably:
    • those underpinning the decommissioning programmes and the storage requirements,
    • the hypotheses determining the shutdown and decommissioning schedule, which will need to be brought into line with those of the multi-year energy programme (PPE) in force.


  • The target level of clean-out and the scope of operations involved in preparation for decommissioning of the facilities included in the evaluation need to be clarified.

Institut Laue Langevin

  • The envisaged duration for the decommissioning of the high flux reactor (RHF) must be reassessed.


  • The evaluation of the provisions for the decommissioning of this facility is insufficient. The three-yearly report submitted by Ionisos contains many gaps and its content does not comply with the regulation obligations in terms of transparency and exhaustiveness.


  • The potential consequences of soil and structural pollution on the La Hague and Tricastin sites must be evaluated.
  • The potential consequences, in terms of safety and financing, of the legacy waste retrieval and conditioning operations and the decommissioning operations on the La Hague site require an in-depth evaluation of the current rate of progress of the projects, in order to substantiate their costs at completion and the sufficiently prudent nature of the amounts of the costs for which provisions have been set aside accordingly.
  • Clarification regarding the Ecrin BNI (BNI no 175) is required.

Synergy Health

  • Some hypotheses need more detailed analysis and greater account needs to be taken of the foreseeable contingencies regarding the decommissioning of the two Gammaster and Gammatec facilities.

ASN has no particular comments concerning the reports submitted by the other basic nuclear installation licensees (Ganil, Cis bio international).

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Date of last update : 03/09/2021