Chernobyl shows Japan the difficult task ahead

From the initial panic at Chernobyl to the lack of a permanent solution 25 years later, it's a lesson in just how hard it is to put the nuclear genie back in the bottle.

Today, radioactivity still leaks from the crumbling structure hastily put up to cover the damaged reactor -- just as it did three years ago, reports CBS News correspondent Bill Plante, who visited the site in 2008.

"Right now the dose rate is something like 200 times over the background you'd have in Washington, D.C.," said Laurin Dodd, of Chernobyl's Shelter Implementation Plan, in 2008.

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Experts say that's about the same as 16 chest x-rays in one day -- and the effect is cumulative.

A more permanent solution to entomb the Chernobyl reactor has been planned for years. It's a massive steel dome, taller than the Statue of Liberty and wider than the St. Louis Gateway Arch.  Construction would take place at a distance because of the radiation, and then rolled into place section by section over the still deadly reactor.

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But the dome hasn't yet begun to take shape. The U.S. and the European Union are still struggling to raise the $2 billion it will cost.

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In Japan, the Fukushima complex will also have to be entombed, and the radiation levels will make that very difficult.

"These reactors are never going to be used again," said James Acton, of the Carnegie Endowment's Nuclear Policy Program. "They're going to have to be entombed for a significant length of time before anything's able to be done about them."

And in Japan, officials are dealing not with just one rogue reactor, but six of them.

"I would hope that we would be able to clean those up with less difficulty than we faced with the one reactor at Chernobyl, but I don't know," said nuclear energy expert Professor Cham Dallas, of the University of Georgia. "With the twists and turn, I don't know that that's a guarantee."

That still unfinished containment dome at Chernobyl is only projected to last 100 years. And Chernobyl, like the Japanese plant at Fukushima, will remain radioactive -- and deadly -- for thousands of years.