2 Nuclear safety of waste management support facilities, role of ASN and waste management strategies of the major nuclear licensees 2.1 RADIOACTIVE WASTE MANAGEMENT METHODS AND THEIR OVERSIGHT BY ASN 2.1.1 The graded approach With regard to radioactive waste management, ASN’s oversight aims on the one hand to verify correct application of the waste management regulations on the production sites (for example with respect to zoning, packaging or the controls performed by the licensee), and on the other hand to verify the safety of the facilities dedicated to radioactive waste management (waste treatment, packaging, storage and disposal facilities). This oversight is exercised in a manner proportionate to the nuclear safety issues associated with each waste management step and each facility. Thus, the waste management BNIs are classified in one of three categories, numbered from 1 to 3 in descending order of significance of the risks and adverse effects they present. This categorisation is taken into account in the preparation of the inspection schedule and helps to determine the level of expertise required for the examination of certain files submitted to ASN by the licensees. The various facilities and ASN’s assessment of their level of safety are presented in the introduction to this report. 2.1.2 Radioactive waste management support facilities Treatment Treatment is a fundamental step in the radioactive waste management process. This operation serves to separate the waste into different categories to facilitate its subsequent management and to significantly reduce the volume of waste. The La Hague plants, which process and recycle the spent fuel assemblies, are involved in this process because they apply a dissolution and chemical treatment process to separate the cladding and the fission products. The hulls and end-pieces are then compacted to reduce their disposal footprint. Centraco, the low-level waste treatment and packaging centre operated by Cyclife France, significantly reduces the volume of the low and very low-level waste that is sent to it. This plant has a unit dedicated to the incineration of combustible waste, and a melting unit in which metal waste is melted down. The radioactive effluents can also be concentrated by evaporation, like the operations carried out in Agate, the Effluent advanced management and processing facility (BNI 171), with this same aim of volume reduction. Packaging Radioactive waste packaging consists in placing the waste in a package which provides a first containment barrier preventing radioactive substances from being dispersed in the environment. The techniques used depend on the physicalchemical characteristics of the wastes and their typology, which explains the large variety of packages used. These packages are subject to approval by Andra if they are intended for existing disposal facilities, and to packaging agreements by ASN if they are intended to be directed towards disposal facilities still under study. In some cases the packaging operations are carried out directly on the site of waste production, but they can also take place in dedicated facilities, like the La Hague plants, which package spent fuel hulls and end-pieces in “Standard compacted waste containers” (CSD-C packages), and the fission products in stainless steel “Standard vitrified waste containers” (CSD-V packages), and the effluent treatment stations such as the Stella station in BNI 35. The conditioned waste packages are sometimes made up in the facilities where they are to be stored, such as for the ILW-LL type CIPGSP packages in the Iceda facility, or directly in a disposal repository, such as the Cires and CSA which carry out these operations for some of the arriving packages. Storage Storage, as defined by Article L. 542‑1‑1 of the Environment Code, is a temporary management solution for radioactive waste. The waste is kept in storage for a limited period (which can extend to 50 years) pending its transfer to disposal, or in order to achieve a sufficient level of radioactive decay to enable it to be sent to conventional waste management routes in the particular case of very short-lived waste, which comes chiefly from the medical sector. Some facilities (see map above) are specifically dedicated to the storage of radioactive waste, such as Écrin, commissioned in 2018, Cedra, commissioned in 2006, and Iceda, commissioned in 2020. This will also be the case of Diadem, once this facility is commissioned around 2026. CSD-C and CSD-V packages will be directly stored in the various facilities on the La Hague site, pending the commissioning of a deep geological repository for HL- and ILW-LL waste. Research and Development Support facilities are used for research and development work to optimise radioactive waste management. Among these, the Chicade facility (BNI 156) operated by CEA on the Cadarache site conducts research and development work on low-level and intermediate-level objects and waste. This work primarily concerns aqueous waste treatment processes, decontamination processes, solid waste packaging methods and the expert assessment and inspection of waste packages. 2.1.3 Oversight of the packaging of waste packages Regulations The Order of 7 February 2012 defines the requirements associated with waste packaging. Producers of radioactive waste are instructed to package their waste taking into account the requirements associated with their subsequent management, and more particularly their acceptance at the disposal facilities. ASN resolution 2017-DC-0587 of 23 March 2017 specifies the requirements regarding waste packaging for disposal and the conditions of acceptance of waste packages in the disposal BNIs. Production of waste packages intended for existing disposal facilities The waste package producers prepare an approval application file based on the acceptance specifications of the disposal facility that is to receive the packages. Andra issues an approval formalising its agreement on the package manufacturing process and the quality of the packages. Andra verifies the conformity of the packages with the delivered approvals by means of audits and monitoring actions on the package producers’ premises and on the packages received at its facilities. 378 ASN Report on the state of nuclear safety and radiation protection in France in 2023 • 15 • Radioactive waste and contaminated sites and soils
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