Prime Minister Fumio Kishida announced on Tuesday that the government has formally ratified the decision to commence the release on Thursday, August 24, pending the absence of unforeseen obstacles.
Over the passage of time, the wastewater has undergone continuous treatment processes to systematically eliminate all removable hazardous components. Subsequently, it has been stored in storage tanks. Notably, a significant portion of the water undergoes a secondary treatment, as confirmed by Tokyo Electric Power Company (TEPCO), the state-owned electricity entity.
When the treated wastewater is eventually released, it will be extensively diluted with fresh, uncontaminated water, leading to only minimal concentrations of radioactive substances. This diluted mixture will be channeled through an underwater tunnel situated approximately 1 kilometer (0.62 miles) off the coastline, ultimately entering the Pacific Ocean.
To ensure transparency and adherence to safety protocols, external parties will closely monitor the discharge process both during and after its execution. The International Atomic Energy Agency (IAEA), the nuclear oversight agency under the United Nations, will be actively involved in this oversight. With an established presence in a newly inaugurated Fukushima office, the IAEA will sustain its vigilance over the situation for the foreseeable future.
The backdrop for this wastewater issue stems from the catastrophic earthquake and subsequent tsunami in 2011. These events inflicted severe damage on the Fukushima nuclear plant’s power infrastructure and cooling systems. As a result, the reactor cores experienced overheating, leading to the contamination of internal water reservoirs with highly radioactive materials.
Since then, efforts have been underway to introduce new water to cool the reactor fuel debris. Unfortunately, this process has inadvertently introduced additional groundwater and rainwater into the site, compounding the volume of radioactive wastewater that necessitates treatment and containment.
Various options were evaluated by Japan for the disposal of the treated water, with five considered in total. Among these, methods such as vapor release, which would involve boiling the wastewater and releasing it into the atmosphere, were explored. Yet, many of these alternatives were deemed “industrially immature” by IAEA Director General Rafael Grossi. Vapor release, for instance, presents challenges in terms of control due to atmospheric factors like wind and rain, which could lead to the re-deposition of waste on Earth. Ultimately, the chosen solution involves the controlled release of water into the ocean, a practice frequently implemented at nuclear facilities worldwide, including those in the United States.