The Japanese Government has provided the IAEA with a report that summarizes the events and highlights the progress related to recovery operations at the Fukushima Daiichi Nuclear Power Station. The IAEA provided its assessments, which are contained in full at the end of the report.
Reduction of groundwater inflow into the buildings & pumped-up groundwater
The IAEA acknowledges the multiple initiatives taken by Japan have reduced the rate of groundwater inflow into the buildings and the pumped up groundwater. These measures include groundwater bypass, sub-drains, land-side impermeable walls using soil freezing and water proof pavement.
Investigations inside the Primary Containment Vessels (PCVs) in Units 2 and 3
The IAEA notes the ongoing progress in the investigation of damaged fuel and fuel debris inside the PCVs and that the information gained from the investigation will help with planning the removal of fuel and retrieval of fuel debris.
The IAEA also notes that spent fuel retrieval from Unit 3 is planned to start in the middle of 2018 fiscal year in Japan, as stated in the revised Mid- and-Long-Term Roadmap of September 2017.
Off-site decontamination
The IAEA acknowledges the efforts undertaken by the Government of Japan as well as the concerned prefectures and municipalities to implement off-site decontamination, including initiation of the operation of the Interim Storage Facility. The IAEA notes Japan’s plans to continue monitoring the air dose rate in the environment and to continue implementing remediation measures, as appropriate.
Sea area monitoring results
Based on the information provided by Japan, no significant changes were observed in the monitoring results for seawater, sediment and marine biota during the period covered by this report. The levels measured by Japan in the marine environment are low and relatively stable. For the purpose of public reassurance, the IAEA encourages the continuation of sea area monitoring, particularly considering the ongoing authorized discharges of treated and monitored groundwater into the ocean.
Sea area monitoring data quality assurance
The IAEA continues to assist the Government of Japan in ensuring that the regularly updated Sea Area Monitoring programme is comprehensive, credible and transparent. The seventh interlaboratory comparison exercise and the fourth proficiency test are currently underway. Seawater, marine sediment and fish samples from coastal waters in the Fukushima Prefecture, which were jointly collected by IAEA experts and Japanese scientists in October 2017, are currently being analysed as part of this seventh interlaboratory comparison exercise. The eighth interlaboratory comparison exercise will be carried out in 2018.
The IAEA considers that the extensive data quality assurance programme helps to build confidence of the stakeholders in the accuracy and quality of the sea area monitoring data.
Food products
Based on the information provided by the authorities of Japan, the situation with regard to the safety of food, fishery and agricultural production continues to remain stable. No significant changes were observed since the previous report. Monitoring foods, appropriate regulatory action and public communication are helping to maintain confidence in the safety of the food supply. Food restrictions continue to be revised and updated as necessary in line with the food monitoring results. This indicates the continued vigilance of the authorities in Japan and their commitment to protecting consumers and trade.
Based on the information that has been made available, the Joint FAO/IAEA Division understands that measures to monitor and respond to issues regarding radionuclide contamination of food are appropriate, and that the food supply chain is controlled effectively by the relevant authorities.