Japan has reached out to the US for help in reining in the crisis at its dangerously overheated nuclear complex, while the UN atomic energy chief called the disaster a race against the clock that demands global cooperation.
At the stricken complex, military fire engines began spraying the troubled reactor units again this morning, with tonnes of water arching over the facility in desperate attempts to douse the units and prevent meltdowns that could spew dangerous levels of radiation.
Last week’s 9.0 quake and tsunami in Japan’s north east set off the nuclear problems by knocking out power to cooling systems at the Fukushima Dai-ichi plant on the coast. Since then, four of the troubled plant’s six reactor units have seen fires, explosions or partial meltdowns.
The unfolding crises have led to power shortages in Japan, forced factories to close, sent shockwaves through global manufacturing and triggered a plunge in Japanese stock prices.
The International Atomic Energy Agency (IAEA) director general Yukiya Amano said: “We see it as an extremely serious accident. This is not something that just Japan should deal with, and people of the entire world should cooperate with Japan and the people in the disaster areas.
“I think they are racing against the clock,” he said of the efforts to cool the complex.
One week after the quake and tsunami, which left more than 6,500 dead and more than 10,300 missing, emergency crews are facing two challenges in the nuclear crisis: cooling the reactors where energy is generated, and cooling the adjacent spent fuel pools where used nuclear fuel rods are stored in water.
Both need water to keep their uranium cool and stop them from emitting radiation, but with radiation levels inside the complex already limiting where workers can go and how long they can remain, it has been difficult to get enough water inside.
Water in at least one fuel pool - in the complex’s Unit 3 - is believed to be dangerously low, exposing the stored fuel rods. Without enough water, the rods may heat further and spew out radiation.
Japanese chief cabinet secretary Yukio Edano said Tokyo is asking the US government for help and that the two are discussing the specifics.
“We are coordinating with the US government as to what the US can provide and what people really need,” he said.
A defence ministry official said a US military fire engine was standing by to help supply water to the crippled reactor units, though he said the vehicle would be driven by Japanese workers.
On Thursday, military helicopters dumped thousands of gallons of water from huge buckets on to Unit 3, and also used Japanese military trucks normally used to extinguish fires at plane crashes.
Televised footage of the air drops showed much of the water blowing away in the wind, and officials announced today they were discontinuing the helicopter missions. But the trucks again began spraying water.
The fire engines allow emergency workers to stay a relatively safe distance from the radiation, firing the water with high-pressure cannons.