Robot May Have Found First Melted Nuclear Fuel Deposits At Fukushima Site Since 2011 Tragedy

New images from an underwater robot may provide evidence of significant melted nuclear fuel deposits on the floor of one of the ill-fated Fukushima nuclear plant’s reactors. This could mark the first time signs of melted fuel have been found since the 2011 earthquake and tsunami destroyed the Japanese nuclear plant.

A report from the Associated Press detailed the results of a three-day investigation conducted on the Fukushima plant’s Unit 3 reactor. According to plant operator Tokyo Electric Power Co. (TEPCO), the company’s robot was able to discover “large amounts” of solidified lava, with thickness estimated to be around the three-foot (one-meter) mark.

In a brief statement quoted by BBC News, a TEPCO spokesman said that the melted nuclear fuel could be Fukushima’s first “highly likely” evidence of such a substance since the 2011 disaster.

“There is a high possibility that the solidified objects are mixtures of melted metal and fuel that fell from the vessel.”

According to a separate report from the Japan Times, TEPCO investigators sent another robot into the Unit 2 reactor in January, and while there were black lumps found on the grating of the primary containment vessel, this debris was written off as being “difficult to identify.”

Further detailing the sightings, BBC News wrote that some of the possible nuclear fuel deposits were similar in appearance to icicles, as they hung around a control rod mechanism found at the bottom of Unit 3’s pressure vessel. TEPCO representatives added that fuel rod assemblies found in that vessel had “melted into a puddle” after the 2011 tsunami, before burning through the bottom.

Investigators also found lumps of melted and re-solidified material near the wall of the pedestal supporting the pressure vessel. Images of these deposits were posted alongside other photos and videos from the three-day operation.

Although it’s been six years since the Japanese earthquake and tsunami resulted in what many believe was the worst nuclear event since Chernobyl in the 1980s, the melted nuclear fuel debris sightings around Fukushima may be followed up with more revelations. BBC News wrote that parts of the nuclear plant’s reactors still have high amounts of toxic radiation as robots perform clean-up operations in the run-up to the plant’s decommissioning.

Due to the high radiation levels and other factors, it may take multiple decades before the Fukushima plant is finally decommissioned. But in the meantime, TEPCO representatives have hinted at further analysis on the melted nuclear fuel deposits found in Fukushima’s Unit 3 reactor, while stressing the importance of finding more debris in each damaged reactor, as far as decommissioning is concerned.

[Featured Image by Christopher Furlong/Getty Images]