- Most of the radioactivity in the water will be removed prior to discharge, and further diluted to concentrations below regulatory limits before it is released into the environment. After it has been released, the radioactivity will be further diluted in the ocean, says Director for Emergency Preparedness at the Norwegian Radiation and Nuclear Safety Authority (DSA), Astrid Liland.
Although most of the radioactive substances will be removed through treatment, tritium is particularly difficult to remove. Therefore, the discharges will mainly contain tritium.
Release data show that the facilities for reprocessing of spent fuel in Sellafield in the UK and La Hague in France have far higher releases of tritium each year than what is planned from Fukushima. The DSA has not observed any negative effects of these tritium releases in the environment or in seafood in Norway.
The IAEA has produced a report in connection with the planned release. Read it here. The IAEA concludes that the planned discharges will have a negligible impact on people and the environment.
Measurements of water from the Fukushima nuclear power plant have been performed in Japan, in four other countries, and by the IAEA. The results show that TEPCO’s reported radioactivity concentrations in the water are correct.
- Assessments on how the discharges will affect the environment have also been made. These show that radiation doses to people and the environment will be low. This is a consequence of the treatment, dilution prior to release, controlled discharges over a long time period, and a further substantial dilution in the ocean, says Liland.
The DSA has followed Japan's clean-up efforts after the Fukushima accident ever since 2011.
- We routinely receive reports on the clean-up work, waste management and future plans. We read these carefully. The planned releases of water will not be noticeable in Norway, says the Director of Emergency Preparedness.
Destroyed by the tsunami
The Fukushima nuclear power plant was hit by an earthquake in 2011. The nuclear power plant was not damaged by the earthquake itself, but by the subsequent tsunami. The tsunami was larger than the power plant was designed to withstand, and large amounts of water flowed into the basement, where all electrical equipment was flooded. Without cooling, the reactor core overheated. Explosions occurred in the reactor building, and these led to leaks and the spread of radioactive substances into the surroundings.