Assessment of the Radiological Impact of Discharge of ALPS Treated Water into the Sea
Following the basic policy, which the Government of Japan announced in April 2021, Tokyo Electric Power Company Holdings conducted assessment on the radiological impact when discharging ALPS treated water into the sea in accordance with internationally recognized methods (as found in the International Atomic Energy Agency (IAEA) Safety Standard documents and International Commission on Radiological Protection (ICRP) recommendations). The assessment was revised based on opinions received from Japan and abroad through a public comment procedure, observations in IAEA reviews and discussions with Nuclear Regulation Authority. The assessment result indicated that the impact on humans and the environment is minimal.
■ Results of the dispersion simulation in the sea (using the meteorological and hydrological data for 2019; annual average)
■Results of radiological impact assessment on humans and the environment (assessment results as of November 2022)
Furthermore, the Government of Japan and other related agencies decided to strengthen and enhance sea area monitoring even before the discharge of ALPS treated water into the sea so that concentrations of tritium and other substances in the sea area can be compared before and after the discharge. In conducting sea area monitoring, the credibility of analysis capabilities is to be secured by obtaining cooperation from the IAEA.
(Source) Prepared based on the “Radiological Environmental Impact Assessment Report Regarding the Discharge of ALPS Treated Water into the Sea (Construction stage)” (November 2022) by Tokyo Electric Power Company Holdings https://www.tepco.co.jp/press/release/2022/pdf4/221114j0101.pdf#page=289
- Included in this reference material on March 31, 2022
- Updated on March 31, 2023