Robot Emerges From Fukushima With a First Clue

A robot that has spent months inside the ruins of a nuclear reactor at the tsunami-hit Fukushima Daiichi plant delivered a tiny sample of melted nuclear fuel on Thursday, in what plant officials said was a step toward beginning the cleanup of hundreds of tons of melted fuel debris. The sample, the size of a grain of rice, was placed into a secure container, marking the end of the mission, according to Tokyo Electric Power Company Holdings, which manages the plant. The sample is being sent to outside laboratories for detailed analyses over the coming months. Plant chief Akira Ono has said it will provide key data to plan a decommissioning strategy, develop necessary technology and robots, and learn how the accident developed, per the AP.

The extendable robot, nicknamed Telesco, first began its mission in August on a planned two-week round trip, after previous missions had been delayed since 2021. But progress was suspended twice due to mishaps—the first involving an assembly error that took nearly three weeks to fix, and the second a camera failure. On Oct. 30, it clipped a sample weighing less than .01 ounces from a mound of melted fuel debris on the bottom of the primary containment vessel of the Unit 2 reactor, TEPCO said. Three days later, the robot returned to an enclosed container, as workers in full hazmat gear slowly pulled it out. Additional small-scale sampling missions will be necessary to obtain more data, TEPCO rep Kenichi Takahara said Thursday.

"It may take time, but we will steadily tackle decommissioning," Takahara said. Despite multiple probes since the 2011 disaster, much about the site's highly radioactive interior remains a mystery. The sample, the first to be retrieved from inside a reactor, was significantly less radioactive than expected. Officials had been concerned it might be too radioactive to be safely tested, even with heavy protective gear. The sample came in well under the limit. The government and TEPCO have set a 30- to 40-year target to finish the cleanup by 2051, which experts say is overly optimistic. Some say it would take a century or longer.

(More Fukushima Daiichi stories.)