Measurement of 14C activity in gaseous effluents from the Bohunice V-1 and V-2 nuclear power plants

A differential sampling device for gaseous effluents from NPP venting stacks, serving the determination of 14C in CO2 and of total 14C (CO2 + hydrocarbons) is described. The sample handling method is outlined, and data are given for the average 14C volume activities measured in the Bohunice V-1 and V-2 NPP venting stacks and the annual 14C effluents from the stacks, evaluated using the results of the monitoring and their comparison with published data. The average total 14C volume activities in the gaseous effluents from the stacks of the two NPPs were about 85 and 56 Bq/m3, respectively, in 1991-1993. The CO2 proportion in the effluents was on the average 25% and 5% for the two plants, respectively. The normalized annual releases of 14C per generated GWe.year are 644 and 418 GBq, respectively, which are higher than the average value for PWRs given in the UNSCEAR 1988 Report, ie., 345 GBq/GWe.a. The radiological impact of the 14C activity on the population in the environs of the Bohunice site is crudely assessed at the regional and local levels. (Z.S.) 2 tabs., 1 fig., 11 refs