TN 81 TRANSPORT / STORAGE CASK FOR HIGH ACTIVITY REPROCESSING WASTE

The return of vitrified High Activity Wastes (HAW) to the foreign countries that have their spent fuel reprocessed in France started in 1995: to Japan with TN 28 V casks. to Germany with Transnucleaire's TS 28 and also other casks. These transports are under preparation for Belgium and Switzerland. In Japan and Belgium, air cooled pits were built for the interim storage of the vitrified waste canisters and to serve the needs of these countries, cask versions adapted to transport only have been designed. In Germany and Switzerland, the interim storage of the waste canisters wi!J take place in \"dual purpose\" cask versions. Such casks will stay in an intermediate storage facility for 40 to 50 years and they must comply with specific requirements such as maximum allowable dose rate at surface, leaktightness monitoring, etc .... They may also have to be specially protected in the event of an aircraft crash. For canisters with a high thermal power (2 kW), current casks can only accommodate a payload of20 canisters and a new cask design was required. The TN 81 cask has therefore been developed to allow transport and interim storage of 28 HAW canisters with a total heat load of 56 kW.