14CH4 emissions from nuclear power plants in northwestern Europe

Abstract

The 14C content of atmospheric methane at a 200-m-high sampling station in The Netherlands was measured . Combined with trajectories and a transport model, it is possible to estimate the 14CH4 emissions from nuclear power plants in northwestern Europe. Two different methods of analyzing the data are demonstrated: forward modeling and an inverse method. Data suggest that the emissions from pressurized water reactors are 260 ± 50 GBq per GW installed power per year, ca. 1.6 ± 0.4 times higher than generally assumed. It is also found that in addition to the known nuclear sources of 14CH4 (pressurized and boiling water reactors), there are two very strong sources of 14CH4 (520 ± 200 and 1850 ± 450 GBq yr-1, respectively), probably two test reactors near the sampling station. -from Authors