Press Releases
Publication of the IAEA Report of Corroboration of Internal Exposure Monitoring for Workers as Part of the Review of Safety Aspects of Handling ALPS Treated Water
On March 24, 2025, the IAEA published a report regarding "IAEA Review of Safety-Related Aspects of Handling ALPS-Treated Water at TEPCO's Fukushima Daiichi Nuclear Power Station: Corroboration of Internal Exposure Monitoring." This report is a compilation of the results of a survey to corroborate TEPCO’s capabilities for measurement of activity to assess the internal radiation doses of workers involved in handling ALPS treated water.
- This survey is based on the Terms of Reference (TOR) on reviews of safety aspects of handling the ALPS treated water signed in July 2021 with the IAEA.
- In this survey, the participating laboratories, including the IAEA laboratory and TEPCO, performed bioassays to assess the internal radiation doses. Based on the results of the comparisons of the measured values, the report draws the following conclusions;
- TEPCO laboratory has demonstrated a high level of accuracy in its measurements and technical competence.
- Analytical procedures follow the appropriate methodological standards required to obtain technically valid results.
- The independent review by the IAEA, an international organization with authority in the field of nuclear energy, is extremely important in ensuring reliability and transparency regarding the safety of the discharge of the ALPS treated water into the sea and fostering better understanding both domestically and internationally. The Government of Japan will continue to work firmly to gain further understanding of the ALPS treated water both domestically and internationally.
(Reference1) ALPS treated water
ALPS treated water is water which is processed by devices such as ALPS (Advanced Liquid Processing System) to ensure that the concentration of the radioactive materials other than tritium surely meets the regulatory standards for safety. In addition, ALPS treated water is sufficiently diluted by seawater before the discharge into the sea so that radioactive materials including tritium are far below the regulatory standards for safety.
(Reference2) Related links
- IAEA Press Release
- IAEA Report (PDF)
- The report “IAEA Comprehensive Report on the Safety Review of the ALPS Treated Water at the Fukushima Daiichi Nuclear Power Station” published on July 4, 2023, summarizes a series of reviews which were conducted by the IAEA before the start of the discharge of the ALPS treated water.
- The report “Corroboration of External Exposure Monitoring for Workers as Part of the Review of Safety Related Aspects of Handling ALPS Treated Water” published on November 11, 2024, summarizes results of a survey by the IAEA to assess the external radiation doses of workers involved in handling ALPS treatment.