Environmental levels of carbon-14 around a Swedish nuclear power plant measured with accelerator mass spectrometry

C-14 is one of the radionuclides which are produced by nuclear power plants, The main part of the C-14, which is released during normal operation, is produced through neutron induced reactions in the cooling water and is released as airborne effluents (such as CO2 and hydrocarbons) through the ventilation system of the plant to the surrounding environment. Because of the biological importance of carbon and the long half-life of C-14, it is of interest to measure the releases and their incorporation into living material in the environment of the power plants. In this pilot study the accelerator mass spectrometry (AMS) facility at the University of Lund has been used to measure the C-14 activity concentration in vegetation around a Swedish nuclear power-plant. AMS is suitable mainly because of the accuracy obtained within a short measuring time, which makes it possible to analyze a sufficient number of samples for a thorough investigation. The results of this study demonstrate that the AMS method is suitable for investigations of the influence on the local environment of reactor-released C-14 by analysis of living material. To test dispersion models, however, air sampling both of emission source and in the surrounding of the plant seems more suitable.