Engineers plan to work into the night to restore power to two of the crippled reactors at Japan’s damaged Fukushima Dai-Ichi power plant, while Prime Minister Naoto Kan described the crisis as “very grave.”
Tokyo Electric Power Co. said it may finish reconnecting a power line to the No. 1 and No. 2 reactors by tomorrow morning. The electrical link would be used to restart pumps needed to protect fuel rods from overheating. However, the company said it’s possible the water pumps, damaged in the March 11 tsunami, might not work even with power, Hikaru Kuroda, chief of Tepco’s nuclear facility management department said tonight in a Tokyo news conference.
“Work on installing external electricity is moving along, but we aren’t yet at a point where power can be restored,” Japan Chief Cabinet Secretary Yukio Edano told reporters.
The U.S. military, which is flying unmanned surveillance drones over the 40-year-old power station about 135 miles (220 kilometers) north of Tokyo at Japan’s request, said it is “cautiously optimistic” that the damage to the reactors can be contained. The risk of a meltdown has lessened after water was dumped on the site yesterday , said Thomas Graham, chairman of Lightbridge Corp., a McLean, Va.-based nuclear fuel developer, said in a Bloomberg Television interview.
“We’re optimistic that we’ll continue to progress in this, and that worst-case scenario will never be encountered,” Admiral Robert Willard, head of the U.S. Pacific Command, told reporters by telephone from Hawaii. The worst-case scenario would be if the effort to keep the cores of the reactors covered were abandoned, he said.
“We believe that that can’t happen, that we must do everything required in order to keep water and cooling affecting these reactors,” Willard said.
The failure of backup generators used to pump cooling water caused explosions in at least three of the structures surrounding the station’s six reactors, as well as a fire in a pond containing spent fuel rods.
Japanese soldiers using fire engines today doused sea water on reactor No. 3, site of an explosion earlier this week. Water cannons and helicopters were used to drench the same reactor yesterday. The dousing was stopped this 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. Spraying may resume tonight.
Risk of Meltdown
The possibility of a meltdown is “not off the table, but the more water that goes in there,” the less the risk of a meltdown becomes,” Graham said. “The reactor situation is definitely not deteriorating as it was and seemingly becoming stable and perhaps becoming more under control.”
If the power cable can be linked successfully, power may be restored to reactors 3 and 4 on Sunday, Tepco spokesman Kaoru Yoshida 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 come from the spent fuel pools that sit on the top of the six reactors.
The Nuclear and Industrial Safety Agency said yesterday 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.
A magnitude 9 earthquake rocked Japan one week ago, setting off a deadly tsunami. The combination of natural disasters cut electricity to the power plant and wrecked backup systems designed to protect the reactors and spent fuel pools from overheating.
As of 2 p.m. in Tokyo, the National Police Agency said 6,539 were killed in the 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.