(Photo : Stored debris from Fukushima nuclear plant. Taken on the 5th of September, 2019.[URL])
On the 1st of February, 2022, the Nuclear Regulation Authority of Japan published a report regarding the radioactivity concentration in seawater. The report is based on the press release of Tepco.
According to this report that reflects the latest oceanic situation after the Fukushima nuclear accident, gross beta nuclides have been detected every day at least since the 29th of December, 2021 except the 16th of January, 2022, when no samples were collected due to bad weather as Tepco stated. The concentration level of gross beta nuclides has consistently been above the safety limit in drinking-water defined by World Health Organization (WHO), which indicates 1Bq/L. The detected concentration level was eight to 14 times higher than the safety limit in every sample. The analysis was implemented in the evaporation drying method.
The sampling location was 1km south of Fukushima nuclear plant. The seawater samples were collected from merely the outer layer, and no data is released about the samples near the bottom of the sea, where it is assumed to highly concentrate the radioactive nuclides from the Fukushima plant.