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| Robot Mission to Retrieve Melted Nuclear Fuel from Japan's Damaged Reactor Halted |
An effort to deploy an extendable robot to extract a piece of melted nuclear fuel from the damaged reactor at Japan’s tsunami-stricken power plant has been paused due to a technical malfunction.
TOKYO (AP) — A planned operation to use an extendable robot for removing a fragment of melted nuclear fuel from the damaged reactor at Japan’s Fukushima Daiichi nuclear power plant was halted on Thursday due to a technical issue.
This effort marks the beginning of the fuel debris removal phase, considered the most difficult stage of the plant’s decommissioning. The Fukushima plant was severely damaged during the 2011 earthquake and tsunami, which led to the destruction of three reactors. Starting with the extraction of a small sample inside Unit 2’s primary containment vessel, this phase is critical for the ongoing cleanup and restoration efforts.
The operation was halted after workers discovered that five 1.5-meter (5-foot) pipes, intended to maneuver the robot, were incorrectly assembled and couldn't be fixed within the allotted time for radiation exposure, according to Tokyo Electric Power Company Holdings (TEPCO).
These pipes were crucial for guiding the robot into and out of the reactor. Once inside the containment vessel, the robot would have been controlled remotely from a safer, low-radiation area.
The robot, capable of extending up to 22 meters (72 feet), was designed to reach its target area and extract a fragment from the surface of the melted fuel using tongs attached to its tip.
The mission to collect the sample and safely return with it was scheduled to last two weeks, though TEPCO has yet to announce a new start date following the setback.
TEPCO President Tomoaki Kobayakawa emphasized that safety remains the top priority over speed, and an investigation into the pipe misalignment is underway.
"I believe the decision to halt the operation when a concern arose was the right one," Kobayakawa told reporters during a visit to Niigata Prefecture, where he engaged with the local community regarding another TEPCO-operated nuclear power plant".
This sample-return mission marks a pivotal first step in the long-term decommissioning of Fukushima Daiichi. However, the objective of retrieving less than 3 grams (0.1 ounce) of radioactive molten fuel—out of an estimated 880 tons—highlights the immense challenges that lie ahead in this multi-decade effort.
Despite the relatively small size of the debris sample, experts agree that it will provide crucial data for developing advanced decommissioning methods and the technology required, including specialized robots. Gaining a better understanding of the melted fuel debris is essential for the safe and effective decommissioning of the three damaged reactors and the entire Fukushima Daiichi plant.
Both the Japanese government and TEPCO are committed to a 30-40-year cleanup timeline established shortly after the meltdown, although some critics argue that this goal is overly optimistic. To date, there are no concrete plans in place for the complete removal or storage of the melted fuel debris.