A Task Force of experts dispatched by the International Atomic Energy Agency (IAEA) collected water samples and scrutinized detailed technical data during their first mission to Japan this week to review the safety of its plan to discharge treated water from the Fukushima Daiichi Nuclear Power Station into the sea.
Established last year by Director General Rafael Mariano Grossi, the IAEA Task Force advanced its independent review by learning more about Japan's planned water release during the 14-18 February mission. It included in-depth scientific discussions and a visit to the site of the 2011 accident where the test sampling of the water took place.
Both in Tokyo and Fukushima, the Task Force observed a commitment to safety in Japan's preparations to release water that has been stored at the site since a powerful earthquake followed by a huge tsunami overwhelmed the plant 11 years ago, a complex undertaking expected to last decades.
The IAEA experts have been gathering information and seeking necessary clarifications in order to be able to conclude that the water discharge plan is consistent with international safety standards.
This week's mission was focused on technical matters related to the roles and responsibilities of the operator, Tokyo Electric Power Company Holdings (TEPCO), and the Ministry of Economy, Trade and Industry (METI) in the water discharge process. The IAEA Task Force will carry out a separate mission towards the end of March to discuss the regulatory aspects with Japan's Nuclear Regulation Authority (NRA).
The Government of Japan announced its Basic Policy in April 2021 to gradually discharge more than 1.25 million cubic metres of treated water into the sea, subject to approval from its independent regulatory body. It requested the IAEA's assistance to help ensure its safe and transparent implementation. Director General Grossi accepted and said the IAEA would conduct the review before, during and after the release and that its active involvement would not only help ensure safety standards compliance but also build public confidence in Japan and the region.
"The mission allowed the Task Force to gain a much better understanding of Japan's plans and activities related to the water discharge," Deputy Director General Lydie Evrard, Head of the IAEA Department of Nuclear Safety and Security, said at a virtual press conference. Evrard, who provides overall oversight of the review and joined the team in Tokyo, added: "This is a significant step forward in the Task Force's work aimed at assessing their adherence to the IAEA safety standards which contribute to high levels of safety worldwide."
The IAEA will release a report on this week's mission in about two months' time with more detail about the specific technical issues discussed, she added. It will also carry out follow-up missions to Japan this year and next, and a comprehensive report with conclusions will be published before the water release starts.
"As a scientific and technical organisation, we will be fully transparent and independent in our reviews and reporting. The world will know what is going on at all times," Director General Grossi has said.
Treated and Stored
In part used to cool melted nuclear fuel, water from the Fukushima Daiichi Nuclear Power Station is treated and purified through a process known as the Advanced Liquid Processing System (ALPS) and then stored in around 1000 tanks at the site. Sustainable water management is key for continued progress in the plant's decommissioning, as the tanks holding the water occupy a large area of the coastal site and are nearing full capacity.
Expected to start about two years after its Basic Policy announcement, Japan intends to release the water with levels of tritium - the only radionuclide that can't be removed through this treatment - well below national regulatory limits and the World Health Organization standards for drinking water. The IAEA Task Force review will provide the public, in Japan and beyond, with objective scientific information about the discharge.
To underline the impartiality and transparency of the IAEA review, the newly established Task Force consists of staff members from IAEA departments and laboratories, as well as eleven independent, internationally recognized experts with diverse technical competencies from Argentina, Australia, Canada, China, France, the Marshall Islands, the Republic of Korea, the Russian Federation, the United Kingdom, the United States, and Viet Nam.
Ahead of the first mission to Japan, the Task Force experts examined safety-related documents provided by their Japanese counterparts, including the implementation plan for the water discharge and TEPCO's radiological environmental impact assessment. They asked detailed follow-up questions during this week's meetings with TEPCO and METI officials.
"The Task Force mission was very productive. We received valuable information - and posed many questions - about all safety aspects of the planned water discharge in frank and open discussions, ranging from the undersea tunnel that will carry the water out to sea to the protection of workers at the site and the public at large," said Gustavo Caruso, a Director within the IAEA Department of Nuclear Safety and Security and Chair of the Task Force.
Independent Water Analysis
To independently verify the levels of radioactivity in the treated water stored in tanks as well as in the ocean, the IAEA will collect water samples for analysis in its laboratories in Austria and Monaco.
Preparing for this important part of the IAEA's review and monitoring, Task Force members on Tuesday observed TEPCO's sampling of treated water in the tanks, some 50 litres of which will be analysed separately by the Agency's laboratories. This will provide useful information as these laboratories further develop scientific methods for corroborating the radioactivity measurement results which will be reported by Japan throughout the discharge.
The IAEA has also welcomed Japan's intention to strengthen environmental monitoring to collect additional data specific to the discharge of treated water, data that will be submitted to the Agency for corroboration in the future.
Under the review's terms of reference agreed with Japan, the IAEA will examine key safety elements of Japan's discharge plan, including:
- The radiological characterization of the water to be discharged.
- Safety related aspects of the water discharge process.
- The environmental monitoring associated with the discharge.
- The radiological environmental impact assessment related to ensuring the protection of people and environment.
- The regulatory control including authorization, inspection, and assessment.
The IAEA and Japan have been cooperating extensively over the past decade to deal with the aftermath of the Fukushima Daiichi accident, in areas such as radiation monitoring, remediation, nuclear safety, waste management and decommissioning. The IAEA's safety reviews are based on its safety standards, which constitute the worldwide reference for protecting the public and the environment from harmful effects of ionizing radiation.
To support the important objective of transparency, the IAEA has established a website that will contain important information and updates regarding the IAEA's review of the water discharge. Additional content will be added over time as the IAEA's review progresses.
"Thanks to our presence, people everywhere can have full confidence that the water discharge is carried out without harming public health or the environment," Director General Grossi said.
