Friday, March 11, 2011

Japanese nuke plants struggling -


TOKYO – Japan declared states of emergency for five nuclear reactors at two power plants after the units lost cooling ability in the aftermath of Friday's powerful earthquake. Thousands of residents were evacuated as workers struggled to get the reactors under control to prevent meltdowns.

A single reactor in northeastern Japan had been the focus of much of the concern in the initial hours after the 8.9 magnitude quake, but the government declared new states of emergency at three other plants in the area Saturday morning.

The earthquake knocked out power at the Fukushima Daiichi plant, and because a backup generator failed, the cooling system was unable to supply water to cool the 460-megawatt No. 1 reactor.

Although a backup cooling system is being used, Japan's nuclear safety agency said pressure inside the reactor had risen to 1.5 times the level considered normal.

Authorities said radiation levels had jumped 1,000 times normal inside Unit 1 and were measured at eight times normal outside the plant. They expanded an earlier evacuation zone more than threefold, from 3 to 10 kilometers (2 miles to 6.2 miles). Some 3,000 people had been urged to leave their homes in the first announcement.

The government declared a state of emergency, its first ever at a nuclear plant. And plant operator Tokyo Electric Power Co. warned of power shortages and an "extremely challenging situation in power supply for a while."

The utility, which also operates reactors at ety," he said at a televised news conference early Saturday.

The agency said plant workers are scrambling to restore cooling water supply at the plant but there is no prospect for immediate success.

Another official at the nuclear safety agency, Yuji Kakizaki, said that plant workers were cooling the reactor with a secondary cooling system, which is not as effective as the regular cooling method.
Kakizaki said officials have confirmed that the emergency cooling system -- the last-ditch cooling measure to prevent the reactor from the meltdown -- is intact and could kick in if needed.

"That's as a last resort, and we have not reached that stage yet," Kakizaki added.
Edano said both the state of emergency and evacuation order around the Fukushima Daiichi plant are precautionary measures.

"We launched the measure so we can be fully prepared for the worst scenario," he said. "We are using all our might to deal with the situation."

Defense Ministry official Ippo Maeyama said the ministry has dispatched dozens of troops trained for chemical disasters to the Fukushima plant in case of a radiation leak, along with four vehicles designed for use in atomic, biological and chemical warfare.
Pineville, La., resident Janie Eudy said her husband, Danny, was working at Fukushima No. 1 when the earthquake struck. After a harrowing evacuation, he called her several hours later from the parking lot of his quake-ravaged hotel.

He and other American plant workers are "waiting to be rescued, and they're in bad shape," she said in a telephone interview.

Danny Eudy, 52, a technician employed by Pasadena, Texas-based Atlantic Plant Maintenance, told his wife that the quake violently shook the plant building he was in. "Everything was falling from the ceiling," she said.

Eudy told his wife that he s can temporarily cool a reactor in this state with battery power, even when electricity is down, according to Arnold Gundersen, a nuclear engineer who used to work in the U.S. nuclear industry. Batteries would go dead within hours but could be replaced.
The nuclear reactor was among 10 in Japan shut down because of the earthquake.
The Fukushima plant is just south of the worst-hit Miyagi prefecture, where a fire broke out at another nuclear plant. The blaze was in a turbine building at one of the Onagawa power plants. Smoke could be seen coming out of the building, which is separate from the plant's reactor, Tohoku Electric Power Co. said. The fire has since been extinguished.

Another reactor at Onagawa was experiencing a water leak.

The U.S. Geological Survey said the 2:46 p.m. quake was a magnitude 8.9, the biggest earthquake to hit Japan since officials began keeping records in the late 1800s.

A tsunami warning was issued for a number of Pacific, Southeast Asian and Latin American nations.
At the two-reactor Diablo Canyon plant at Avila Beach, Calif., an "unusual event" -- the lowest level of alert -- was declared in connection with a West Coast tsunami warning. The plant remained stable, though, and kept running, according to the NRC.

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