Workers at a troubled Japanese nuclear power plant have discovered plutonium in the soil and several radioactive pools of water around the facility, confirming fears contaminated water is leaking out of damaged reactors into the nearby environment.
Emergency crews have been working to contain the situation at the Fukushima Dai-ichi nuclear plant since a massive 9.0-magnitude earthquake hit Japan on March 11. On Monday, they fought to pump out tons of water that had been used to cool the reactors, but was then contaminated after a partial meltdown.
The discovery of plutonium-laden soil was announced Monday after tests results on samples taken a week ago were made public. The vice-president of plant operator Tokyo Electric Power Co., Sakae Muto, said it does not pose a risk to human health.
Also Monday, officials revealed that several contaminated pools of water had been discovered the previous day. They are located in an underground maintenance tunnel and the basements of several buildings, and mark the first time highly radioactive water has been found outside the damaged reactors. Radiation in the pools was measured at 1,000 millisieverts per hour, a level high enough to cause temporary radiation sickness.
The tunnel ends just over 50 metres from the shore of the Pacific Ocean, fuelling fears it could seep in to the ocean waters surrounding the plant.
At least three of the station's six reactor units are believed to have partially melted down since the huge wave engulfed much of the plant, destroying its crucial cooling systems.
While some of the plant has been reattached to the power grid, the contaminated water must be pumped out before electricity can be restored to the cooling system.
That means workers have two somewhat contradictory goals: pumping in water to keep the fuel rods cool and then pumping out and safely storing the contaminated water.
Officials are still looking at safe ways to store the radioactive water.
A TEPCO official said there has been no evidence so far that water from the pools has made its way to the ocean. But there has been much skepticism of the company's ability to handle the crisis after it released an inaccurate reading of the radioactivity of the contaminated water in the Unit 2 reactor.
While initially saying radiation in the reactor had been measured at 10 million times higher than normal, it later revised that figure to 100,000 times normal amounts. TEPCO spokesperson Takahi Kurita said that initial measurement was "not credible" and that the company is "very sorry" for the confusion.
On Monday, Japan's chief Cabinet Secretary Yukio Edano said TEPCO's miscalculation was "not something that can be forgiven." He urged the public to respect the evacuation order that pertains to a 20-kilometre radius around the plant, saying that contaminants pose a "big" health risk.
The Fukushima Dai-ichi nuclear plant, located about 220 kilometres northeast of Tokyo, was plunged into chaos after the earthquake triggered a deadly tsunami that disabled cooling systems at the coastal facility.
Plant workers have since battled fires, explosions, aftershocks and severe radiation hazards at the site as they have fought to stave off meltdowns within Dai-ichi's six reactors.
Japan's Kyodo News Agency reported that 19 plant workers have been exposed to radiation levels that exceed legal limits for workers dealing with a nuclear emergency.
In the nearby ocean, contamination has now spread about 1.6 kilometres farther north of the plant than previously determined.
Hidehiko Nishiyama, a spokesperson for Japan's Nuclear and Industrial Safety Agency, told reporters that radioactive iodine-131 was found offshore from the Unit 5 and Unit 6 reactors at a level 1,150 times higher than normal.
Closer to the plant, radioactivity in seawater has jumped from being 1,250 times normal levels last week to 1,850 times normal as of Monday. Nishiyama said the increase was concerning, but the elevated radiation was occurring in an area that is not a source of seafood for Japan.
Nishiyama said he suspects radioactive water is leaking from the plant into the ocean, an opinion shared by Japan's Nuclear Safety Commission which warned Monday that radioactive water was seeping from the plant into both the soil and seawater.
Amid reports residents have been sneaking back into the evacuation zone, the government again warned residents to stay away for the sake of their own health and safety.
With files from The Associated Press
