A robot has been deployed into the ruins of the Fukushima Daiichi nuclear reactor by Tokyo Electric Power Company Holdings to collect a tiny sample of melted nuclear fuel. This sample, the size of a grain of rice, will be used for further analysis to aid in planning the cleanup of hundreds of tons of melted fuel debris at the plant. The mission ended successfully, culminating in the secure transportation of the sample to a glove box for measurement before being sent to outside laboratories for detailed analysis in the coming months. Plant chief Akira Ono has stated that this data will be crucial in devising a decommissioning strategy and developing the necessary technology and robots for the cleanup process.
Despite previous probes done in the years following the 2011 disaster that wrecked the Fukushima Daiichi plant, much remains unknown about the interior of the highly radioactive site. Initial concerns regarding the radioactivity of the sample were quickly dispelled, as the sample turned out to be less radioactive than expected. The robot, named Telesco, faced various delays and mishaps during its mission, including an assembly error and camera failure. However, it was successful in extracting a sample weighing less than 3 grams from the surface of melted fuel debris in the Unit 2 reactor’s primary containment vessel. This sample retrieval marks the first time melted fuel has been retrieved from inside a reactor at Fukushima Daiichi.
The Fukushima Daiichi plant experienced meltdowns in three reactors after losing key cooling systems during an earthquake and tsunami in 2011, resulting in an estimated 880 tons of highly radioactive melted fuel remaining in the reactors. The government and TEPCO have set a target of completing the cleanup by 2051, which some experts view as overly optimistic and suggest an updated timeline of a century or longer. While no specific plans have been decided for the full removal and disposal of the fuel debris, government officials remain confident in the overall decommissioning process despite some delays.
With the successful retrieval of the melted fuel sample, TEPCO aims to continue with additional small-scale sampling missions to gather more data for the cleanup efforts. The safe removal of the sample from the reactor marks a significant milestone in the decommissioning process and sets the stage for further progress in tackling the remaining melted fuel debris. The data obtained from the samples will aid in the development of technologies and robots necessary for future cleanup missions inside the highly radioactive reactors at Fukushima Daiichi.
Ongoing efforts to extract melted fuel from the Fukushima Daiichi plant are crucial in fully understanding the extent of the damage caused by the 2011 disaster and in developing strategies for safe and effective cleanup. TEPCO remains determined to tackle the challenges posed by the highly radioactive environment inside the reactors and is committed to achieving the long-term goal of fully decommissioning the site. The successful collection and analysis of melted fuel samples represent a significant step forward in the cleanup process, paving the way for further advancements in technology and robot deployment to address the remaining melted fuel debris.
