The discharge of treated water from Japan's Fukushima Daiichi Nuclear Power Station (FDNPS) is proceeding in line with international safety standards, the International Atomic Energy Agency (IAEA) Task Force confirmed today in its third report since the water discharge began in August 2023.
During its mission to Japan from December 9 to 12, 2024, the Task Force assessed the technical and regulatory aspects of the ALPS-treated water discharge. This included an on-site visit to the FDNPS facility to directly observe the equipment and infrastructure installed by Japan's Tokyo Electric Power Company (TEPCO), the operator of the FDNPS for the water discharge. The report also summarised the Task Force's discussions with the Nuclear Regulation Authority (NRA), Japan's Ministry of Foreign Affairs (MOFA) and Ministry of Economy, Trade and Industry (METI).
The Task Force report reaffirmed the findings of the IAEA's comprehensive safety review, stating that its overall conclusions remain consistent with those from its first and second missions conducted after the discharge began. It emphasized that Japan's NRA has maintained a comprehensive inspection plan, including onsite monitoring to ensure the safety of the water that is discharged. Additionally, the Task Force confirmed that the equipment and facilities are operating in accordance with relevant international safety standards.
In the IAEA Comprehensive Report on the Safety Review of the ALPS-Treated Water at the Fukushima Daiichi Nuclear Power Station that was released in July 2023 prior to the discharge, the IAEA found Japan's approach to discharging the treated water to be consistent with international safety standards. It also said that the discharges as planned would have a negligible radiological impact to people and the environment. The IAEA Task Force has carried out eight missions as part of the safety review since the beginning of the IAEA's multiyear review that began two years before the water discharge.
Today's report also reviewed the IAEA's ongoing independent verification of Japan's monitoring programs, as well as onsite sampling and analysis conducted by IAEA experts at FDNPS since July 2023, when Director General Rafael Mariano Grossi established an IAEA office at the site. The IAEA's onsite laboratory has analyzed the first eleven water discharges, confirming that the tritium concentration in each batch of diluted ALPS-treated water remains well below Japan's operational limit consistent with international safety standards.
The Task Force noted the importance of the IAEA's ongoing corroboration activities and the IAEA onsite independent sampling and analyses in providing a comprehensive, transparent and independent verification of the accuracy and reliability of the data reported by TEPCO and the Government of Japan.
Interlaboratory Comparisons
The IAEA has also released reports today on two interlaboratory comparisons (ILCs) for determining radionuclides in ALPS-treated water and in marine environmental samples collected from near to FDNPS, part of the Agency's comprehensive monitoring and assessment efforts.
ILCs involve multiple laboratories independently analyzing samples, then reporting their results to the IAEA for evaluation to assess their reliability and accuracy.
One report presents the findings from an ILC based on samples collected during a mission in October 2023 when the IAEA, with experts from third-party laboratories, observed Japan's collection and pretreatment of samples of seawater, sediment, fish and seaweed from coastal and offshore locations and a fish market close to FDNPS. Laboratories in Canada, China and the Republic of Korea, as well as the IAEA's laboratories in Austria and Monaco, analysed the samples and reported the results to the IAEA for intercomparison.
The IAEA report confirms that Japan's methods for sampling follow the appropriate methodological standards and that Japanese laboratories have reported accurate results that demonstrate a high degree of proficiency. The IAEA notes that these findings provide confidence in Japan's capability for conducting reliable and high-quality monitoring related to the discharge of ALPS treated water.
The second ILC report, also released today, corroborates Japan's source monitoring of ALPS treated water from the eighth batch prior to discharge in August last year. Water sampled from the tanks was analysed in laboratories in China, the Republic of Korea, Switzerland and the United States, as well as in the IAEA laboratories. Following assessment of the results submitted, the IAEA said the findings provide confidence in TEPCO's capability for conducting reliable and high-quality source monitoring.
Corroboration of Internal Exposure Monitoring
Additionally, the Agency released a report today confirming that TEPCO is accurately monitoring the internal radiation exposure of workers handling ALPS-treated water.
The report presents the findings from ILCs organized by the IAEA last year, which corroborated results from IAEA, French and Japanese laboratories. The findings highlight that TEPCO has demonstrated both a high level of accuracy in their measurements and strong technical competence. A report focusing on external radiation exposure monitoring was published in November 2024.
All reports, as well as additional information such as frequently asked questions and a timeline of activities, can be found on the IAEA's Fukushima Daiichi ALPS Treated Water Discharge webpage.
