RETURN OF THE FUEL FROM THE GERMAN COMPACT SODIUM-COOLED NUCLEAR FACILITY KNK II WITH THE CASTOR® KNK

The Compact Sodium-Cooled Nuclear Reactor Facility KNK II, located at the Karlsruhe Institute for Technology (KIT), the former Research Center Karlsruhe, has been operated from 1977 to 1991 as a prototype facility for the Fast Breeder Reactor SNR 300. The fuel of the KNK II consisted of fuel assemblies (FA) with highly enriched Uranium-/Plutonium-MOX fuel (up to 93 % 235U enrichment and up to 35 % plutonium in the heavy metal). The fuel rods were transported to C.E.A. (France) in 1993 for reprocessing. However, due to the low solubility of the MOX fuel 2413 fuel rods from 27 FA could not be reprocessed. They were encapsulated and stored in a pool of the French research centre Cadarache operated by the Commisariat à l'énergie atomique (C.E.A.). In a German-French fuel return project organised by Wiederaufarbeitungsanlage Karlsruhe Rückbauund Entsorgungs-GmbH (WAK), these fuel rods will be returned to Germany to be stored for a maximum of 40 years in the interim storage facility ZLN operated by Energiewerke Nord GmbH (EWN). For the return and the interim storage of the fuel, 4 transport and storage casks of the type CASTOR® KNK were designed and fabricated by GNS Gesellschaft für Nuklear-Service mbH especially for this project. The transport is organised by Nuclear Cargo + Service GmbH (NCS) and will be performed in one batch by road and rail. The project started in September 2001, the planned project deadline is end of 2010. The presentation gives an overview of the already finished project tasks (submission of the German cask approval certificate and storage approval for the CASTOR® KNK, validation of the cask certificate in France, fabrication of the 4 casks and the equipment, cask cold handling in France and Germany and the additional encapsulation of the fuel in Cadarache) on the one hand and the open tasks on the other hand (transport from France to Germany, storage of the casks in the ZLN).