(CH4)-C-14 EMISSIONS FROM NUCLEAR-POWER-PLANTS IN NORTHWESTERN EUROPE

We measured the C-14 content of atmospheric methane at a 200-m-high sa mpling station in The Netherlands. Combined with trajectories and a tr ansport model, it is possible to estimate the (CH4)-C-14 emissions fro m nuclear power plants in northwestern Europe. We demonstrate here two different methods of analyzing the data: forward modeling and an inve rse method. Our 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. We also find that, in add ition to the known nuclear sources of (CH4)-C-14 (pressurized and boil ing water reactors), there are two very strong sources of (CH4)-C-14 ( 520 +/- 200 and 1850 +/- 450 GBq yr(-1), respectively), probably two t est reactors near the sampling station.