Fukushima recovery robot may have finally discovered what happened inside reactor 3

Vaughn Highfield July 24, 2017

It’s been six years since the nuclear incident at the Fukushima Daiichi reactor, and salvage teams have finally made progress in discovering what happened at the site.

One of Tokyo Electric Power Company’s custom-made Toshiba remote-control submarine robots has successfully made its way inside reactor 3 at Fukushima to discover potential fuel debris, according to the Japan Times. Hanging like stalactites around a control rod drive, it’s likely these are the remnants of the fuel rods that melted and burned through the bottom of the reactor’s pressure vessel after it lost power during the 11 March 2011 tsunami.

The discovery of such waste is a huge step forward in Tepco beginning its cleanup operation. Tepco had previously used robots to investigate the reactor but, thanks to radiation levels of 650 sieverts per hour, all of their circuitry was fried within minutes (a person would have died within seconds). Tepco’s next job is to classify these deposits as fuel so it knows what to look for in future investigations.

“From the pictures taken today, it is obvious that some melted objects came out of the reactor,” said Takahiro Kimoto, a Tepco spokesperson. “This means something of high temperature melted some structural objects and came out. So it is natural to think that melted fuel rods are mixed with them.” Kimoto then confirmed that the team were thinking about how these objects can be properly analysed as resolidified nuclear fuel.

Tepco’s plan is to begin discussions around removing the resolidified fuel this summer, with the actual procedure taking place in 2021. The entire reactor decommissioning process is slated to cost $72 billion (£55.3 billion) and could take up to 40 years to complete.

Not only is removing the melted fuel from the reactor the starting point for this cleanup process, it’s also an opportunity to learn what actually happened inside the reactor and help prevent it from happening again. Research in understanding nuclear energy and reactors has the potential to save millions of lives.

A research paper published in Science back in May pointed to how US nuclear experts were relying on “faulty analysis” that could lead to a catastrophic fire at any one of dozens of nuclear reactors in the US. All it would take is a large earthquake or a targeted terrorist attack and a fire could erupt, leading to around eight million people having to relocate.

fukushima-power-plant Fukushima power plant with tanks storing 750,000 tonnes of irradiated groundwater

Strangely enough, Tepco believes the residential areas of Fukushima around the reactor should be safe and so the process of moving residents back in began last year. The biggest challenge for resettling people is ensuring that groundwater isn’t contaminated and isn’t seeping into the ocean.

If the prospect of a nuclear disaster on the scale of Fukushima – or worse – has you scared, it’s worth noting that, while the US is the only nation to have dropped a bomb in conflict, there have been more than 2,056 known nuclear detonations in history.