It’s been nearly six years since a tsunami damaged the Fukushima Daiichi nuclear power plant in Japan’s northeast, causing a devastating meltdown of three nuclear reactors. Scientists are still managing the disaster, and new readings measured inside reactor No 2 are the highest recorded since the accident, The Guardian recently reported.
Tokyo Electric Power Company (Tepco), the owner of the power plant spearheading efforts to decommission the site, used a camera to look inside the reactor.
They discovered that the metal capsule used to hold the nuclear material within the containment unit had likely melted through the receptacle’s bottom.
The result is a three-foot hole in the grating, sitting just underneath. Images from the efforts also reveal black debris that could be melted nuclear fuel—the first material located by Tepco in the years following the disaster.
Fortunately, the material is contained and only poses a risk within the protective barrier of the outer vessel.
“It may have been caused by nuclear fuel that would have melted and made a hole in the vessel, but it is only a hypothesis at this stage,” Tatsuhiro Yamagishi, a Tepco spokesman, told Agence France-Presse. “We believe the captured images offer very useful information, but we still need to investigate given that it is very difficult to assume the actual condition inside.”
That investigation could be difficult, given that the area is contaminated by 530 sieverts of radiation an hour. That’s the highest it has been since 2012 when it reached 73 sieverts. In perspective, one sievert is enough to cause radiation sickness, infertility, and cataracts; exposure to 10 sieverts will kill someone in just a matter of weeks.
That sounds bad, but scientists have noted that this does not necessarily mean radiation levels are increasing. Radiation in this particular area has never been measured before and was expected to be extremely high. They do, however, interfere with Tepco’s plans to continue exploring the vessel in the coming weeks. The hole in the grating will cause operators to find another route for the remote-operate vehicle they intended to use. The vehicle can also only withstand 1,000 sieverts of radiation—meaning it will only have two hours before it will be disabled, compared with the ten that were expected.
“Confirming the conditions inside the reactor is a first step toward decommissioning,” Hiroshige Seko, Minister of Economy, Trade, and Industry said in a statement. “While difficult tasks and unexpected matters may arise, we will mobilize all of Japan’s technological capabilities to steadily implement decommissioning work and rebuild Fukushima.”
At the end of last year, the Japanese government revised a 2013 estimate of the costs of accomplishing this to $190 billion—double its initial estimate.
Interestingly, an opinion poll has revealed that more than 80 percent of the Japanese population does not believe the government’s information regarding the nuclear crisis. The spread of radiation to the West Coast of North America was acknowledged, but quickly dismissed when reports indicated that only “tiny amounts of radioactive particles have arrived in California but do not pose a threat to human health.”
That’s a slight misrepresentation, given that 800 terra becquerels of Celsium-137 are expected to hit the West Coast of North America.