Prime Minister Naoto Kan said Japan’s nuclear crisis remained “very grave” as forecasts indicated changing winds could start moving radiation closer to Tokyo by the end of the weekend.
Engineers worked overnight to restore power to two reactors at the crippled Fukushima Dai-Ichi plant in a bid to get cooling systems running again. By March 20, the weather may take emissions toward the capital, 135 miles (220 kilometers) south of the station, Austria’s meteorological center said, using data from the Comprehensive Test-Ban Treaty Organization. At current levels, the radiation isn’t dangerous beyond the immediate vicinity of the plant, the center said.
“The situation at the power plant is still unpredictable,” Kan said at a press conference in Tokyo yesterday. “But we’re making our utmost effort to control it, and we’ll surely overcome this crisis.”
Japan faces a “battle with time,” International Atomic Energy Agency Director General Yukiya Amano said after meeting ministers in Tokyo. A magnitude-9 earthquake and tsunami March 11 knocked out Fukushima’s back-up generators, pitching workers into a battle to keep the plant cool and stem radiation from the worst nuclear accident since Chernobyl 25 years ago.
Tokyo Electric Power Co. said it may finish reconnecting a power line to the No. 1 and No. 2 reactors by this morning. The electrical link would be used to restart pumps needed to protect fuel rods from overheating. It’s possible the water pumps, damaged in the tsunami, might not work even with power, said an official from Tepco, as the company is known.
“We must avoid being overly optimistic,” Philippe Jamet, a commissioner at the Autorite de Surete Nucleaire, France’s nuclear regulator, said at a briefing in Paris yesterday. “This will likely take human intervention like going into control rooms to reconnect valves.”
Japanese soldiers used fire engines yesterday to dump sea water on reactor No. 3, site of an explosion earlier this week. The dousing was stopped in the afternoon as the effort replenished some water to the spent-fuel pools at the reactor, Air Self Defense Force Chief of Staff Shigeru Iwasaki said.
“On Sunday, a frontal system is crossing the region with heavy rain,” Austria’s Meteorological and Geophysics Center said in a statement. “Behind the front, northerly winds are predicted, increasing the risk for the region around Tokyo.”
Radiation has been detected in eastern Russia at levels that pose no risk to human health, said the center, which was set up in 1996 to detect nuclear-test explosions. A “minuscule” amount of radiation that probably came from the damaged Japanese reactors was picked up at a California monitoring station yesterday, the U.S. government said.
Images posted on the Austrian center’s website show intense radionuclide concentrations around the reactors. Wind currents take the plume in a winding pattern over the Pacific Ocean, setting the particles adrift in north- and south-easterly patterns.
The failure of backup generators used to pump cooling water forced the venting of gas that caused explosions in at least three of the buildings surrounding Fukushima’s six reactors. A fire also started in a pond containing spent fuel rods from reactor No. 4.
Prime Minister Kan said the government is being as transparent as possible about the crisis, rebutting criticism that it had held back information.
“Everything has been disclosed to the Japanese public,” Kan said. “We have shared what we know with the international community.”
Japan upgraded its warning for some parts of the plant from a four to a five on a seven-level international scale, the IAEA said yesterday. The five rating is for accidents with wider consequences. The worst nuclear accident, Chernobyl in 1986, rated seven.
Tepco acknowledged its No. 1, 2 and 3 reactors at the site had been changed to a level five rating, according to a statement on the company’s website.
If the power cable can be linked successfully, power may be restored to reactors 3 and 4 on Sunday, Kaoru Yoshida, a Tokyo Electric spokesman, said in a briefing to reporters. Still, there is a potential risk of an explosion if the power is reconnected to the reactor, Japan’s Nuclear and Industrial Safety Agency said. The agency didn’t provide details.
The greatest risks at Fukushima may still come from the spent fuel pools that sit on the top of the six reactors.
The Nuclear and Industrial Safety Agency said March 17 there is a possibility of no water at the No. 4 reactor’s spent-fuel cooling pool. If exposed to air, the fuel rods could decay, catch fire and spew radioactive materials into the air.
As of 2 p.m. yesterday in Tokyo, the National Police Agency said 6,539 were killed in last week’s disasters, 10,354 are reported missing, 2,513 were injured and 382,613 people have been evacuated. More than 536 aftershocks have been recorded by the U.S. Geological Survey.