- 57 - Finally, the inspectors noted that all the facilities do not have a procedure for managing the stowed position of the cranes and other large lifting devices, considered to be potential sources of hazards in the event of an earthquake. To conclude, the inspections conducted on the Tricastin site as a whole show that the licensees in general comply with the seismic strength requirements stipulated in their safety frame of reference but that they would have difficulties with managing an accident situation further to a major earthquake, owing to the loss of electrical power supplies, means of communication, supervision of the facility or to the non-seismic design of the auxiliary premises, crisis or fall-back centres, and premises housing the resources and personnel of the FLS. The licensees also failed to consider the potential hazard that certain items can constitute in the event of an earthquake: appropriate protections and procedures are not systematically identified and implemented. Nuclear fuel fabrication facilities (Mélox, FBFC) For Mélox, the creation authorisation decree of 21st May 1990 stipulates the design and construction objectives to be met: maintain and guarantee the functions important for safety, that is confinement of materials and prevention of the criticality risk. The earthquake to be considered is level VIII-IX (MSK), the response spectrum being established on the basis of resonators appropriate to the site. Mélox was built on backfill of high-grade materials resting on the alluvial layer. Exposure to site effects is currently being assessed. As of the design stage, the potential effects of an earthquake on the confinement of material (not guaranteed, responsibility transferred to the first civil engineering barrier), the risk of criticality (the option being to keep the material localised and guarantee sub-criticality regardless of the secondary control mode), the handling risk, the risk from the release of heat and the risks of fire and explosion, were taken into account. Furthermore, the licensee considered ensuring the safe state of the facility in the event of an earthquake, by studying the conditions determining management of the associated risks and linked to the loss of electrical power and the loss of the facility's control system. In the event of an earthquake, production is stopped and the facility is shut down to a "safeguard" safe state. The equipment that is required to remain functional after an earthquake (backup controls, batteries, cableways associated with safeguard I&C), along with the routes giving access to the safeguard command post, are designed in accordance with seismic standards. The facility is in conformity with its frame of reference. The civil engineering works and equipment for which integrity must be guaranteed in the event of an earthquake, have been identified according to precise safety objectives. Seismic detection is threshold-based, internal and without recording. In the event of an alarm or pre-alarm, the facility switches to safeguard operations. With regard to the SSE, sub-criticality is guaranteed by keeping the materials localised, with the dispersible fraction being contained by the civil engineering structures at the interface between the cells and the glove boxes or shielded chains (barrier transfer). No off-site emergency services response time is stipulated. If the site were to be isolated, the measures and resources to be used would be those associated with the flood risk. All of these provisions, in conjunction with the one-week self-sufficiency in the event of isolation, are a strong point in favour of the Mélox plant. For the off-site intervention resources, the inspectors noted that in the event of an earthquake which could affect all the facilities on the Marcoule site, there is no guarantee that the emergency response manpower levels allocated to intervention on the Mélox facility would be sufficient. Finally, the inspectors found that the instrumentation is the original equipment and does not meet current standards. The licensee conducted an obsolescence study as part of the complementary safety assessment. In the FBFC facilities, only the buildings necessary for production (buildings C1 and AP2, and HF station) are built to SSE standards, either owing to their original design, or as a result of the renovation work carried out since 2006. The other buildings (especially those intended to house the crisis command post
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