BN-350 Reactor facility decommissioning activities: strategy, management, performance

摘要

The BN-350 reactor is a fast breeder reactor using liquid sodium as a coolant. In 1999 theGovernment of the Republic of Kazakhstan adopted the Decree on the decommissioning of this reactor facility.According to this Decree, Kazakhstan Government intends to place the BN-350 facility into a safe storage(SAFSTOR) condition for a period up to 50 years. "The Plan of priority measures for BN-350 reactordecommissioning" was developed to realize the Government Decree and to determine the scope of activitiesaimed at reactor safety within the period before "Decommissioning Project" will be prepared. This plan includesthe following measures: transportation of spent fuel assemblies;handling primary/secondary sodium andradioactive wastes;preparation of reactor building and premises for SAFSTOR period and completion of BN-350 reactor decommissioning project. Since 1999 the works have been intensively conducted according to thisPlan. There have been certain management problems which have been encountered by the general responsibleorganizations. By now a considerable amount of works concerning the transitional period from an operating to adecommissioning status have been performed in the framework of the chosen decommissioning strategy andlicensing requirements, e.g.: primary sodium has been cleaned of caesium radionuclides, drained from BN-350reactor vessel/primary loops in to the primary sodium storage tanks and solidified there;creation of sodiumprocessing facility is under way;design of the casks for spent fuel transportation and storage has beencompleted;systems for processing liquid/solid radioactive wastes are being designed.