During a fuel crud removal operation on the Paks-2 unit on 10 April 2003, several fuel assemblies were severely damaged. The assemblies were being cleaned in a special tank of the Paks Nuclear Power Plant, Hungary under deep water level in a service pit connected to the spent fuel storage pool. The first sign of fuel failure was the detection of some fission gases released from the cleaning tank. Later visual inspection revealed that most of the thirty fuel assemblies suffered heavy oxidation and fragmentation. The first evaluation of the event showed that severe fuel damage occurred due to inadequate cooling.
The Paks-2 event was discussed in various committees of the NEA and the International Atomic Energy Agency (IAEA). Recommendations were made to undertake actions to improve understanding of the incident sequence and consequences that this had on the fuel. It was considered that the Paks-2 event may have constituted as a useful case for comparative exercises on safety codes, in particular for models devised to predict fuel damage and potential gas releases under abnormal cooling conditions. Analyses on the Paks-2 event would have also provided information relevant for in-reactor and spent fuel storage safety evaluations.
The OECD-IAEA Paks Fuel Project was established in 2005 as a joint project between the IAEA and the OECD/NEA. The IAEA provided financial support to the operating agent (Hungarian Academy of Sciences KFKI Atomic Energy Research Institute (AEKI)) and reviewed the progress of the project within the framework of the IAEA Technical Co-operation Programme, RER/9/076, Strengthening Safety and Reliability of Fuel and Material in Nuclear Power Plants.
A final report was published in 2010 and can be found below.
The data abstract is public.
International Atomic Energy Agency, Safety Assessment Section, Vienna (Austria) (2010), "OECD-IAEA Paks Fuel Project Final Report", International Atomic Energy Agency (IAEA).
Belgium, Finland, France, Germany, Hungary, Russian Federation, Slovak Republic and United States.
November 2004-November 2007
Sponsored by the IAEA.