Floating Nuclear Power Plant “Akademik Lomonosov”: Radionuclide Composition of Emissions and Radiation Situation in the Location Area

The article presents unique experimental results on the radionuclide composition of gas-aerosol emissions from the world's first marine-based small modular reactor (SMR) with light water cooling, which is operating at the “Akademik Lomonosov” floating nuclear power plant (FNPP). For the first time, the key radionuclides ( 3 H, 14 C, and 41 Ar) that account for at least 95% of the annual effective dose for the population in the SMR location area (Pevek, Russia) during normal operation were identified. The normalized release into the atmosphere of these radionuclides amounted to 2.72·10 -1 , 2.91·10 -3 and 1.53·10 -2 GBq (GW·hr) -1 , respectively. The emission of all identified radionuclides resulted in radiation exposure of the Pevek population less than 0.03 μSv yr -1 . The obtained values of normalized release could be used as a baseline for assessing compliance with the INPRO methodology for all subsequent marine-based SMR projects. Studies of the radiation situation in the Pevek area revealed no statistically significant differences in the dose rate, radioactive fallout rate, or radionuclide composition of the soil and ground before and after the commissioning of the FNPP. External irradiation from the surface of the soil and ground in Pevek is caused only by natural radionuclides from the decay chains of uranium, thorium, and 40 K. Artificial radionuclides typical of NPP release were not detected in the surveyed areas.