Recent developments in the licensing and manufacturing control procedures of DPCs

Recent developments in the licensing and manufacturing control procedures of DPCs BackgroundSince 2001 high active waste and spent fuel is stored in various designs of DPCs. A specific Swiss challenge is the variety of fuel types. Until 2006 all Swiss Utilities sent spent fuel for reprocessing. This included the return of equivalent amounts of high active vitrified waste for dry storage. The reprocessing products were used for manufacturing MOX- and Urep-elements, which were again used in the PWR-reactors. The stop of reprocessing changed the utilities fuel strategy to maximum enrichment and burnup with subsequent dry storage. As a consequence DPC designs had to be adapted to accommodate the increasing heat load and radioactive inventory.Licensing and Regulatory ControlENSI has implemented following licensing strategy: Transport design certificates according to /1/, and specific design approvals for storage facility as specified /2/.Early approvals concerned unmodified foreign DPC designs. Hence the foreign transport certificate could easily approved based on the simplified validation process. This changed when the specific Swiss fuel characteristcs had to be adressed in DPC designs: such designs require a dedicated full scope check of the transport safety assessment report (SAR). In parallel and for each DPC design the storage safety analysis report (TSAR) has to be approved. SAR and TSAR are closely correlated and modifications of one most probably also leads to updates of the other, which is why Switzerland started early activities on the idea of an integrated safety case analysis report covering both areas and one of the next applications for design approval will be based on an integrated safety analysis report.ENSI published a guide on implementation of comprehensive ageing management programs /3/.This paper intends to give a comprehensive overview on the Swiss regulatory approach to DPC licensing and correlated regulatory activities and corresponding most recent international developments.References /1/International Atomic Energy Agency (IAEA)Regulations for the Safe Transport of Radioactive Material (SSR-6)2012/2/HSKRichtlinie HSK-G05: Transport- und Lagerbehälter für die ZwischenlagerungApril 2008/3/ENSIAlterungsleitfaden tockene ZwischenlagerungDezember 2018