Lessons learned from the shut down, planning, and the preparatory activities ofdecommissioning the research reactor VVR-S Magurele, Bucharest

摘要

The nuclear research reactor type VVR was shut down in December 1997 after forty years ofoperation. The main characteristics of this reactor are: Thermal power 2 MW, Thermal energy – 9.59 GWhd,Average flux of thermal neutrons-1013 n/cm2.s, nine horizontal channels, sixteen vertical exposure channels, threebiological channels, reactor type tank, water used as a moderator, coolant and reflector. The reactor was used inresearch and radioisotope production. The reactor has been permanently shut down since April 2002, when thedecommissioning was officially announced. Discussions regarding funding mechanisms for the conservation phase,and decommissioning (planning, preparatory activities, spent nuclear fuel management), have taken place since fiveyears ago when the final decision of permanent shut down was taken.Quality management includes procedures for recording and archiving the lessons learned. The planning ofdecommissioning started in 1990 when the reactor was still operational. After fifteen years the regulatory body hasnot yet approved the decommissioning plan for the reactor. In this paper the following aspects are discussed:decommissioning strategy from safe enclosure to immediate dismantling, specific features of the site (treatment ofradioactive waste near reactor) and state of decommissioning, use of the lessons learned in the planning ofdecommissioning for the other two small nuclear facilities situated in the same area with VVR-reactor: Sub criticalAssembly " HELEN" and Zero Power Critical Reactor RP-0, AFR ponds for spent nuclear fuel, other radiologicalfacilities for radioisotopes production facilities radiation processing and accelerators.Preparatory activities for decommissioning have included: elaboration of a plan (inter alia, justification of theselected strategy, management of the radioactive waste in accordance with the waste acceptance criteria), reactorstorage in parallel with the removal of the equipment and materials used in research activities and radioisotopeproduction. The organizational management safety, human resources, and social aspects, development of the localcommunity, public relations, are also to be dealt with as lessons learned for exchange of experience, information andknowledge in the field of decommissioning.