The decommissioning of old nuclear facilities is a major challenge for Orano which – over the coming decades – will be required to carry out several large-scale decommissioning projects: the first-generation fuel processing plant at La Hague, called UP2-400 (BNI 33), with its support units (the waste treatment station STE2 and the spent fuels reprocessing plant AT1 (BNI 38), the radioactive sources manufacturing workshop ELAN IIB (BNI 47) and the “oxide high activity” facility, called (BNI 80)), as well as the uranium enrichment and conversion plants at Tricastin (BNI 93 and BNI 105).
The legacy waste retrieval and conditioning operations (referred to as RCD) are among the first steps in decommissioning. These are of particular importance given the inventory of radioactive substances present and the age of the facilities in which they are stored, which do not meet current safety standards. RCD projects are characterised by major safety and radiation protection challenges, as well as by considerable industrial complexity. The general decommissioning of these facilities will also create a large quantity of waste, which will need to be safely managed.
Since 2005, ASN has been regularly evaluating Orano’s decommissioning and waste management strategy for the La Hague and Tricastin sites. At ASN’s request and given the complexity of these subjects, their interdependence and the delays observed on certain priority projects, the licensee updated its strategy in 2016.
ASN investigated this strategy and, after discussions with the licensee, observed progress in the assimilation of the goals of immediate dismantling, monitoring of the governance of complex projects (creation of a major projects department, a project maturity evaluation procedure and the development of project progress monitoring tools), the progress of the operations on several Tricastin facilities, as well as the definition of final waste conditioning processes for the La Hague site.
However, ASN asks Orano to improve its strategy in the following four areas:
- the implementation of the decommissioning and waste management strategy must be prioritised according to the risks (existing pollution or high potential source term). The construction of new effluent and waste conditioning, storage, transport and treatment capacity will be needed to enable this strategy to be implemented, given the existing weak points (storage facilities that do not meet current safety standards, uncertainties regarding the medium-term saturation of certain storage facilities, etc.);
- the implementation of the clean-up strategy must be based on sufficient knowledge of the current state of the facilities, and more particularly the civil engineering structures and soils. If complete clean-out is not possible, an appropriate clean-out strategy taken as far as is reasonably achievable in acceptable technical and economic conditions shall be deployed;
- the implementation of the RCD strategy must be better managed and the potential source term must be reduced as early as possible. The characterisation of the waste and qualification of the processes envisaged must be actively pursued in order to define the required processes and demonstrate their feasibility within a time-frame compatible with implementation of the RCD projects. The waste currently stored in temporary facilities and for which there is no operational solution or which requires preliminary treatment, shall be transferred as rapidly as possible to storage facilities compliant with current safety requirements;
- the oversight of complex projects must be improved by analysing the causes of delays to the priority projects and by examining the adequacy of the resources devoted to these projects.
ASN also underlines the need for the licensee to inform the public of the progress of its programmes.
It is up to Orano to ensure that this strategy is implemented and to report on it regularly to ASN. Given the safety and radiation protection issues encountered, ASN very regularly checks progress, by means of dedicated investigations, inspections, technical meetings and a project oversight approach.
Thanks to this heightened oversight, ASN adapts its regulatory methods to these high-stakes projects. Its intention is to transition from a “static” approach – in which the project completion deadline is set out in the regulations, often a long time in the future, and with calendar drift that is detected too belatedly – to a “dynamic” approach, focused on a precise analysis of the actions planned by the licensee over the coming 5 years.
In this new approach, having strengthened its RCD projects programming and oversight methods, the licensee submits detailed schedules to ASN, including milestones for which it makes a binding commitment to ASN. This may consist of safety studies or studies to develop certain aspects of the project, placing of industrial contracts or the completion of actual physical steps in the progress of the project, such as the beginning of construction of new equipment. On the basis of this detailed 5-year programme, ASN will specify key milestones for this period and will check that they are reached. This sliding process will continue until the final waste retrieval and conditioning result is achieved.
To find out more (in french):
Date of last update : 24/03/2022