Monitoring of Atmospheric Excess ¹⁴C Around Paks Nuclear Power Plant, Hungary

The activity of radiocarbon in 14 CO 2 and 14 C n H m chemical forms is measured in the vicinity of Paks nuclear power plant (NPP), Hungary, by sampling environmental air. Four differential sampling units at different sites collected samples less than 2 km away from the 100-m-high stacks of Paks NPP, and for reference a sampler was operated at a station ∼30 km away from Paks NPP. We present the results of continuous observations at the 5 stations covering the time span from 2000 to 2005. The samples have been analyzed by a proportional counting technique. During a cleaning tank incident at unit 2 of Paks NPP in April 2003, a significant release of radioactive isotopes took place from the damaged fuel assemblies, and gaseous products escaped through the chimney. We evaluate the possible short- and long-term impact of this incident on the 14 C content of the atmosphere in the surroundings of Paks NPP. Comparing our 14 CO 2 measurements with data sets from Jungfraujoch and Schauinsland, as well as from Košetice (Czech Republic), we demonstrate that the incident had no definite influence on the 14 C content of the atmosphere.