ASN conducted four inspections in 2024. The verifications focused in particular on the primary system, including the treatment of deviations on the three primary/secondary heat exchangers, components of the reactor pile block, including the “core inlet” natural convection valve and the reflectors and the control rod drive mechanisms of the core, as well as the chemically-sealed anchorings. The repair of the reactor pool liner also underwent inspections, as did the qualification process for various items of equipment involved in the facility’s safety functions, the centralised instrumentation and control system and the fire protection of the electric cable raceways. The thematic examinations of the facility’s safety analysis report revision submitted in 2021, taking account of the modifications made since the start of construction, continued in 2024 in preparation for the future commissioning. The examination of the request to modify DAC 2009-1219 of 12 October 2009 to extend the commissioning date to 14 October 2037 at the latest, taking into account margins for the project, continued in 2024. ASN considers the project organisation to be broadly satisfactory from the nuclear safety aspect, particularly in the handling of the deviations on the primary heat exchangers and the development of tools to ensure the application and traceability of the defined requirements. The project must ensure that the qualification process for protection important components is carried out conclusively for all the defined requirements. The formalising and application of certain processes must also be improved. Lastly, continued vigilance is required regarding the priority to be granted to the protection of interests, and to the constant efforts to improve the measures taken to protect these interests. ITER The International Thermonuclear Experimental Reactor (ITER – BNI 174), under construction on the Cadarache site since 2010 and adjacent to the CEA facilities, will be a fusion experimental reactor used for the scientific and technical demonstration of the control of thermonuclear fusion energy obtained by magnetic confinement of a deuterium-tritium plasma during long-duration experiments with a significant power level (500 MW developed for 400 seconds). This international project enjoys financial support from China, South Korea, the United States, India, Japan, Russia and the European Union, who make in-kind contributions by providing equipment for the project. The large quantities of tritium that will be brought into play in this installation, the intense neutron flow and the resulting activation of materials have serious implications regarding radiation protection and will represent true challenges for the safe management of waste during the operation and decommissioning of the installation. ITER Organization (IO) presented a new baseline for the project in 2024 further to the revision initiated in 2022. This new roadmap provides for operation in several phases corresponding to the main sequences of the experimental programme, and contains modifications in some of the facility’s design choices, notably the replacement of beryllium by tungsten as the liner material for the first wall of the vacuum chamber. This new roadmap moreover takes account of the difficulties the licensee has identified in providing a conclusive safety case covering the entire lifetime of the project, and proposes the principle of producing a staged safety case, following the successive phases of commissioning and operation. The reason for this is that the safety case for certain operating phases requires the acquisition of certain information and data that will not be available until the preceding phases have been completed. ASN has taken note of this approach which seems appropriate for the exploratory nature of the ITER project, such as is provided for by its authorisation decree. ASN points out that this approach presents a potential industrial risk for the project should the technical choices made and the knowledge acquired at a given stage finally not enable the licensee to demonstrate control of the nuclear safety and radiation protection risks for the subsequent steps. ASN observes however that the elements provided in 2024 do not yet make it possible to establish an overall view of the decided changes and their impact on the different project components. This concerns, for example, components that have already been examined but for which some of the hypotheses are being modified. The first revisions of the schedule, integrating more specifically the assessment of the impact of the Covid-19 pandemic, the repair times for the sectors and thermal shields, and the projected modifications to the machine, were submitted in 2024. These elements must still be consolidated with respect to the project’s new commissioning strategy and the defining of the technical files to be examined at each stage of the reference scenario. ASNR will be attentive to the assessment of the impact of these modifications on the nuclear safety and radiation protection risks, and to the technical requirements of the amended resolution of 12 November 2013 regulating the design and construction of the facility. ASNR is thus waiting for conclusive elements to redefine the scheduling of its examinations and to adopt a position regarding the acceptability of the impact of the intended modifications. IO should submit a new application for authorisation to lift the hold point concerning assembly of the vacuum chamber in 2026. Work on the site and equipment manufacturing continued in 2024, notably with the repair of the first sectors of the tokamak to correct the dimensioning differences and to resolve the problem of stress corrosion affecting the heat shield cooling systems. The quality of manufacture of the tokamak is of major importance for safety because of its role in radioactive substance containment, which must be ensured for all the phases of operation planned for in the reference scenario of the facility. In 2024, ASN continued the technical examination of the new authorisation application for water intakes and discharges of non–radioactive effluents for the facility construction phase submitted in 2023. Five inspections were carried out on the site in 2024, focusing in particular on the design and construction and the monitoring of outside contractors. These inspections included checks of the repair of the vacuum chamber sectors, the facility’s fuel supply systems and the equipment of the Vacuum Vessel Pressure Suppression System (VVPSS). 96 ABSTRACTS – ASN Report on the state of nuclear safety and radiation protection in France in 2024 Regional overview of nuclear safety and radiation protection PROVENCE‑ALPES‑CÔTE D’AZUR
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