Faculty of Mathematics, Physics
and Informatics
Comenius University Bratislava

Nuclear Seminar - Jakub Kaizer (22.5.2024)

Wednesday 22.5.2024 at 14:00, Lecrure room F1/364

16. 05. 2024 10.03 hod.
By: Jaroslav Staníček

Ing. Jakub Kaizer, PhD.:
Assessment of the environmental impact from discharging of tritium-contaminated water from Fukushima

In August 2023, the long-planned discharging of radioactive wastewater from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) started after the confirmation of its feasibility and safety. As this water contains elevated amounts of tritium even after being diluted, a lot of resources have been invested in the monitoring of the Fukushima coastal region where the discharge outlet is located. We compare the first 3H surface activity concentrations from these measurements (up to the end of November 2023) with the available background values to evaluate a possible impact of the long-term discharging on humans and environmental levels of the radionuclide of interest in the same or nearby area. From our results, we can conclude that the joint effect of horizontal and vertical mixing has been significant enough to reduce tritium concentrations at the monitored locations in the region close to the FDNPP port two days after the end of the respective phase of the discharging beyond the detection limit of the applied analytical methods (~ 0.3 Bq L-1). Moreover, the distant correlation analysis showed that stations located further than 1.5 km from the outlet were impacted by the discharging to a similar level. We also estimated that the 3H activity concentration in the offshore Fukushima region would be elevated by 0.01 Bq L-1 at maximum over a year of continuous discharging, which is in concordance with the already published modelling papers and much less than the impact of the FDNPP accident in 2011.