Japan's Nuclear Regulation Authority announced Wednesday that it will raise the threat level at the Fukushima Daiichi nuclear-power plant following revelations that radioactive water has leaked out of storage facilities nearby. The event marks the first time the nuclear regulator has declared a radiological release at the site since an earthquake and a tsunami caused three of the plant's nuclear reactors to melt down in 2011.
For the past two years, Tokyo Electric Power Company, the plant's operator, has been working to stop the spread of nuclear contamination. Each day, plant workers inject mass quantities of water into the failed reactors to prevent them from overheating. This has, however, created a new set of hazards.
Water used to cool the reactors becomes contaminated with radioactive material as soon as it passes through their cores. So what has Tepco been doing with the water? It's storing it in close to 1,000 tanks built on the grounds of the power plant. For a long time, this was assumed to be safe. But now, one of the tanks is leaking.
Tepco confirmed Tuesday that 300 tons of radioactive water have seeped out of one of the storage tanks. According to Reuters the water "is so contaminated that a person standing close to it for an hour would receive five times the annual recommended limit for nuclear workers." In other words, the situation is critical. Plant workers responded by piling sandbags around the leaking container. But most of the water had already seeped into the ground by the time the effort got underway.