A robot deployed inside the ruins of a nuclear reactor at the tsunami-affected Fukushima Daiichi plant successfully retrieved a tiny sample of melted nuclear fuel on Thursday. The sample, equivalent in size to a grain of rice, was securely placed into a container, marking the completion of the mission. Tokyo Electric Power Company Holdings, the plant's operator, confirmed that the sample will undergo size and weight measurements before being sent to external laboratories for detailed analyses in the coming months.
The data obtained from this sample is crucial for devising a decommissioning strategy, developing necessary technology and robots, and understanding the progression of the accident, according to plant chief Akira Ono. While the initial sample is a significant milestone, further small-scale sampling missions will be required to gather additional data for the decommissioning process.
Despite previous probes conducted since the 2011 disaster that severely damaged the plant, much about the highly radioactive interior of the site remains unknown. The retrieved sample, the first from inside a reactor, was found to be less radioactive than anticipated, raising questions about its origin. However, TEPCO officials maintain that the sample is indeed melted fuel.
The robot, known as Telesco, began its mission in August with a planned two-week duration but faced delays due to technical issues. On October 30, it successfully collected a sample weighing less than 3 grams from the melted fuel debris in the Unit 2 reactor's primary containment vessel. The sample was then securely stored for removal from the compartment.
Fukushima Daiichi suffered meltdowns in three reactors following the 2011 earthquake and tsunami, leaving an estimated 880 tons of highly radioactive melted fuel. The government and TEPCO aim to complete the cleanup by 2051, although experts suggest this timeline may be overly optimistic and require adjustments. Specific plans for the full removal and disposal of the fuel debris are yet to be finalized.
Chief Cabinet Secretary Yoshimasa Hayashi assured that despite some delays, the overall decommissioning process will not be affected. The successful retrieval of the melted fuel sample marks a significant step towards addressing the aftermath of the Fukushima Daiichi disaster.
