Interim storage packagings for spent fuels : how to optimize an universal design to local needs

For the last ten years, the interim storage market for spent fuels issued from Nuclear Power Plants has significantly increased all over the world: there are presently many storage projects either in Asia, in North America and in Europe. Even if there is no international regulation on that field, there is a big concern from all the nuclear industry to try to harmonise the specification for the definition of the Interim Storage Systems. One example of this harmonisation is the common and general wish to develop systems, which allow to be easily transportable either to a final repository or to a reprocessing plant. As this destination is generally not yet known, the storage system should be able to be transported all over the world. On the other hand, the specific requirement for the storage facility and its associated equipment are subject to local and/or national regulation. COGEMA LOGISTICS Group has developed two different technologies which are compatible with this principle of harmonisation: dual purpose metallic cask represented by the TN24 family and the concrete storage system NUHOMS(R). For both technologies, basic designs can be adapted to the local needs in term of performance and of national regulation. To cover all the world, COGEMA LOGISTICS Group has its own subsidiaries, in Asia, in North America and in Europe with their own autonomous engineers teams for designing, licensing, manufacturing and delivering the transport/storage products. COGEMA LOGISTICS Group is presently the leader on the dry interim storage market. The purpose of the present paper is to show how it is possible to optimise a basic existing design of a dual purpose metallic cask for a local need of storage. Taking into account the national rules for storage and the international regulation for transport, the designer shall minimise the development cost for a completely new design and maximise the capacity of the packaging regarding the allowable limits in the Nuclear Power Plant, in the Storage Facility and during the transport