ASN Report 2020

1.3  Materials storage facilities The materials storage facilities operated by the CEA are primarily devoted to the conservation of non-irradiated (or slightly irradiated) uranium and plutonium-bearing fissile materials from other CEA facilities. This activity enables the laboratories (Atalante, Lefca, etc.) to be supplied according to the needs of the experiments being conducted. More recently, they have become a temporary storage solution for the fissile materials which were present in facilities that are now shutdown, such as the research reactors (Éole, Minerve, Osiris, Masurca, etc.). Principles and safety issues The main challenges inherent in these facilities are to prevent the dispersal of radioactive substances and to control the chain reaction (criticality). The safety of these facilities is based on a series of static physical barriers (walls and doors of rooms and buildings) to prevent the dispersal of radioactive substances. When operations are carried out on these substances, static confinement is also provided by the equipment (glovebox, shielded cell) in which these operations are performed. This static confinement is supplemented by dynamic confinement consisting on the one hand of a cascade of negative pressure environments between the rooms where there is a risk of radioactive substance dissemination and, on the other, filtration of the gaseous releases into the environment. The chain reaction is controlled by strict instructions regarding the handling, storage and monitoring of the materials being stored. Dedicated storage facilities The Magenta facility (BNI 169), commissioned in 2011 and operated by the CEA on its Cadarache site, is dedicated to the storage of non-irradiated fissile material and the non-destructive characterisation of the nuclear materials received. It is more particularly replacing the Central Fissile Material Warehouse (MCMF – BNI 53), which was finally shut down at the end of 2017. Materials storage areas in BNIs Other radioactive material storage areas, located within a BNI, are authorised to store radioactive materials on the site, but in quantities far lower than those stored in Magenta. This is for example the case with BNI 55, called STAR, which stores spent fuels and fuels irradiated following reprocessing and/or conditioning. 2. ASN actions concerning research facilities: a graded approach 2.1  The graded approach according to the risks in the facilities The BNI System applies to more than about a hundred facilities in France. This System concerns various facilities with widely differing nuclear safety, radiation protection and environmental protection challenges: nuclear research or power reactors, radioactive waste storage or disposal facilities, fuel fabrication or reprocessing plants, laboratories, industrial ionisation facilities and so on. The safety principles applied to nuclear research or industrial facilities are similar to those adopted for nuclear power reactors and “nuclear fuel cycle” facilities, while taking account of their specificities with regard to risks and detrimental effects. ASN has implemented an approach that is proportional to the extent of the risks or drawbacks inherent in the facility. In this respect, ASN has divided the facilities under its oversight into three categories from 1 to 3 in descending order of the severity of the risks and drawbacks they present for the interests mentioned in Article L. 593-1 of the Environment Code (ASN resolution 2015‑DC-0523 of 29 September 2015). This BNI classification ITER installation – base of the cryostat being lowered into the Tokamak ASN Report on the state of nuclear safety and radiation protection in France in 2020 335 12 – NUCLEAR RESEARCH AND MISCELLANEOUS INDUSTRIAL FACILITIES 12