Leaks Plugged and Nitrogen Flooding Begins at Nuclear Plant

No we are not out of the woodsyet.  The leak caused by a crack had tobe found and plugged.  In the meantimewater is been thrown at overheated reactors. What we are not seeing are fuel rods been recovered.  Skip the slagged parts which we all know willbe as difficult as TMI was, but let us get the working rods pulled and secured.  This reduces potential risk from a seriousexplosion.

Without a working cooling systemthe system is plausibly unable to cool at all now.  Thus extracting the fuel itself may well bethe only way to shut the thing down.

What is true is that with theleak plugged, the situation is at least stable for now.  Perhaps they have a little breathing room toput together a decommissioning plan. Certainly retracting the fuel rods must be a priority.  The wreaked sections will likely need specialequipment fabricated to order and this will take time.

Preventing blasts a focus at Japan nuclear plant

AP – ADDS WHEN AND WHERE - Tokyo Electric Power Co. (TEPCO)Managing Director Naomi Hirose, front left, bows …

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By MARI YAMAGUCHI, Associated Press – Wed Apr 6,3:42 pm ET

TOKYO – After notching a rare victory by stopping highly radioactive waterfrom flowing into the Pacific on Wednesday, workers at Japan's floodednuclear power complex turned to their next task: injecting nitrogen to preventmore hydrogen explosions.

Nuclear officials said there was no immediate threat of explosions likethe three that rocked the FukushimaDai-ichi plant not long after a massive tsunami hit on March 11, but theirplans are a reminder of how much work remains to stabilize the complex.

Workers are racing to cool down the plant's reactors, which have beenoverheating since power was knocked out by the 9.0-magnitude earthquake andtsunami that killed as many as 25,000 people and destroyed hundreds of miles ofcoastline.

Unable to restore normal cooling systems because water has damaged themand radioactivity has made conditions dangerous, workers have resorted topumping water into the reactors and letting it gush wherever it can.

Superheated fuel rods can pull explosive hydrogen from cooling water,so now that more water is going into the reactors, the concern is that hydrogenlevels are rising.

Technicians began pumping nitrogen into an area around one of theplant's six reactors at 1:31 a.m. Thursday (1631 Wednesday GMT; 12:31 p.m.Wednesday EDT) to counteract the hydrogen, said Makoto Watanabe, a spokesmanfor Japan'sNuclear and Industrial Safety Agency. They want to prevent hydrogen explosionsthat could spew radiation and damage the reactors.

The nitrogen pumping also has risks, but the nuclear agency approved itas a necessary measure to avoid danger, spokesman Hidehiko Nishiyama said. Theinjection could release radioactive vapor into the environment, but residentswithin 12 miles (20 kilometers) of the plant have been evacuated.

The government said Wednesday it might consider expanding that zone,though not because of the nitrogen injection. An expansion might notnecessarily mean the radiation that has been spewing into the air and waterfrom the plant is getting worse. The effects of radiation are determined byboth the strength of the dose and the length of exposure, so the concern isthat people farther away might start being affected as the crisis drags on.

"I would imagine residents in areas facing a possibility forlong-term exposure are extremely worried," Chief Cabinet Secretary YukioEdano said. "We are currently consulting with experts so that we can comeup with a clear safety standard."

Edano did not say how far the zone might be expanded or how many peoplemight be affected. Tens of thousands have been living in shelters since thetsunami, either because they lost their homes or are in the evacuation zone orboth.

Police in hard-hit Fukushimaprefecture prepared to launch a full-scale search for bodies in the evacuationzone Thursday. Nearly 250 agents from the TokyoMetropolitan Police will join local police searching for 4,200 people stillmissing there.

At the plant, 140 miles (220 kilometers) northeast of Tokyo, workers finally halted the leak ofhighly contaminated water that raised worry about the safety of seafood caughtoff the coast.

But even that rare good news came with a caveat. Highly contaminatedwater pooling around the plant has often made it difficult or impossible forworkers to access some areas because of concerns about radiation exposure. Nowthat the leak has stopped, the pooling could actually get worse because waterthat had been going into the ocean could back up onto the grounds of thecomplex.

When water was still leaking into the ocean, officials said it wouldquickly dissipate in the vast Pacific, but the mere suggestion that seafoodcould be at risk stirred worries throughout Japan's fishing industry. Waterwith lower levels of radioactivity is also being dumped into the sea to makeroom to store other water with higher levels of contamination on the plantgrounds.

In the coastal town of Ofunato,Takeyoshi Chiba, who runs the town's wholesale market, warily watcheddevelopments at the plant, about 120 miles (200 kilometers) down the coast.

"There is a chance that the water from Fukushima will come here," he said,explaining that area fishermen still haven't managed to get out to sea againafter the tsunami destroyed nearly all of their boats. "If Tokyo decides to banpurchases from here, we're out of business."

This week, the government set its first-ever standard for the amount ofradiation allowed in fish after levels in waters near the plant measuredseveral million times the legal limit and elevated levels were found in somefish. The standard is the same as one already in place for vegetables.

Stopping the leak by injecting several chemicals into the area aroundit seemed to help cut down on radiation. By afternoon, radiation at a point 360yards (330 meters) off the coast was 280 times the legal limit, down from ahigh of more than 4,000, although Edano said plant operator Tokyo ElectricPower Co. was still watching closely.

"Right now, just because the leak has stopped, we are not relievedyet," Edano said. "We are checking whether the leak has completelystopped, or whether there may be other leaks."