The discharge of treated water from Japan's Fukushima Daiichi Nuclear Power Station (FDNPS) continues to comply with international safety standards, the International Atomic Energy Agency (IAEA) Task Force confirmed today. In its second report since the water discharge began in August last year, the Task Force established to review the safety of Japan's treated water discharge into the sea also reaffirmed the conclusions from the IAEA's comprehensive safety report.
Today’s report from the Task Force covers the finding of its mission to Japan from 23 to 26 April, the seventh since it was established in 2021. The Task Force visited the FDNPS site and discussed technical issues with Japan’s Ministry of Economy, Trade and Industry (METI) and Tokyo Electric Power Company (TEPCO) – operator of the plant – during its April visit. The Task Force also met with the Nuclear Regulation Authority (NRA).
The IAEA’s comprehensive report last year – issued on 4 July last year before the discharge began – found Japan’s plan for handling the treated water to be consistent with international safety standards and that the discharge as planned would have a negligible radiological impact to people and the environment.
TEPCO started to discharge the water on 24 August 2023 and intends to continue discharging the water in batches. The total water discharged so far is approximately 55 000 cubic metres, following completion of the seventh batch on 16 July. IAEA expert analysis of the seven batches released have confirmed the tritium concentration in each batch of ALPS treated water released to date is far below Japan’s operational limit.
During its April mission, the Task Force visited the facilities and equipment installed at the FDNPS to discharge the ALPS (Advanced Liquid Processing System) treated water. This included the measurement tanks holding the water prepared for discharge, the flow control valves, emergency isolation valve and the seawater pumps. The Task Force also reviewed the radiation monitors and flow rate detectors installed throughout the discharge facilities, which provide live data to the IAEA’s real time monitoring page.
Additionally, as part of the mission’s activities, the Task Force reviewed the status of the IAEA’s independent corroboration of Japan’s source and environmental monitoring programmes, and the onsite sampling and analysis activities conducted by IAEA experts at the FDNPS. The IAEA is conducting a series of interlaboratory comparisons (ILCs) to corroborate the source and environmental monitoring conducted by TEPCO and other relevant Japanese authorities for the ALPS treated water discharge.
Based on their assessments made during the April mission, the Task Force also concluded the following:
- The regulatory infrastructure in place is appropriate to provide operational safety oversight of the discharge of ALPS treated water, and the Task Force was able to witness first-hand the continuous onsite presence of the NRA and their activities in this regard.
- The Task Force confirmed that the equipment and facilities are installed and operated in a manner that is consistent with Japan’s Implementation Plan for the water discharge and the relevant international safety standards.
- The Task Force noted the importance of the IAEA’s ongoing corroboration activities and its on-site independent sampling and analyses, in providing a comprehensive, transparent and objective verification of the accuracy and reliability of the data reported by TEPCO and the Government of Japan and to help build confidence.
IAEA Director General Rafael Mariano Grossi established the Task Force in 2021 to ensure a transparent and inclusive safety review of Japan’s plans for the water discharge. Comprised of IAEA and independent experts from 11 different countries and chaired by a senior IAEA official, the Task Force advises the IAEA in their individual capacities, bringing diverse technical viewpoints to ensure a comprehensive review against international safety standards. The standards constitute the worldwide reference for protecting the public and the environment from harmful effects of ionizing radiation.
The report from the Task Force’s first mission after the discharge was issued in early 2024.
As part of its ongoing multiyear safety review, the IAEA will continue to conduct Task Force review missions. The next review mission is anticipated to take place in the last quarter of 2024. The Agency also maintains its continuous presence at the IAEA Fukushima Daiichi NPS Office – established by Director General Grossi in July 2023 – to monitor and assess the ongoing water discharge.
Additional information such as frequently asked questions and a timeline of activities can be found on the IAEA’s dedicated Fukushima Daiichi ALPS Treated Water Discharge webpage.