A worker checks the status of the water level at the Unit 1 reactor at the Fukushima Dai-ichi nuclear power plant in Japan on Tuesday. Japanese officials said the reactor doesn't appear to be holding water, which means its core probably sustained more damage than originally thought.
A worker checks the status of the water level at the Unit 1 reactor at the Fukushima Dai-ichi nuclear power plant in Japan on Tuesday. Japanese officials said the reactor doesn't appear to be holding water, which means its core probably sustained more damage than originally thought.
The U.S. Nuclear Regulatory Commission held a hearing Thursday on its effort to learn from the reactor troubles in Japan following the devastating earthquake in March.
Commission staff made only passing reference to a newly discovered water leak at the Fukushima Dai-ichi plant. Japanese officials said Thursday the plant is in worse shape than they realized. The Unit 1 reactor doesn't appear to be holding water, which means its core has probably sustained more damage than officials thought and cleanup will be even tougher.
But Bill Borchardt, the NRC's executive director for operations, told commissioners that conditions overall in Japan are more or less under control.
"While they change, they're not changing at such a rapid pace that it's causing any kind of undo concern," he said.
The commission is in the midst of a rapid, 90-day review to see whether U.S. reactors are vulnerable to catastrophic failure based on what has been learned so far from Japan. Commission staffer Charlie Miller said the review so far has not identified any issue that undermines confidence in U.S. reactors.
That said, a lot of the discussion Thursday dealt with the adequacy of so-called "severe accident management guidelines" to deal with a severe accident, such as a major fire, dam-burst upstream or a power blackout that lasts for days. They're all rare events that are above and beyond what plants are designed to withstand.
"SAM-Gs, as they're known, were implemented as a voluntary initiative by the industry in the 1990s, and they're not covered by our regulations," Miller said. "Consequently, we do not evaluate them as part of the agency's routine reactor oversight process."
Since the NRC doesn't send inspectors in to check on these safety plans, the commission has instead sent around a notice, asking companies for an update. It's still waiting word back on that. But Martin Virgilio from the NRC said an informal survey did uncover some irregularities.
"None of the observations posed a significant safety issue, but there were observations ... in some cases: equipment that was relied on that would not start, that it had not been maintained," he said.
And in some cases there were inadequate procedures and training. Power companies told the NRC these problems are all fixed now. But that led NRC Commissioner George Apostolakis to wonder whether voluntary guidelines for severe accidents are really the best way to go.
"I went back and looked at the station blackout rule, and that's paradise," he said.
Paradise for the industry to comply with, he said, since it just has to submit a report showing it has a credible plan, and that's that. No inspections. No follow-ups.
"So the licensee has tremendous freedom to do all these things, maybe supported by some statistical analysis. And then they will say, 'Well, we went to Sears and bought a portable diesel,' and everybody says we're happy," he said.
Apostolakis acknowledged that's a bit of an exaggeration, but still, surely this is an area where the commission can do better. Borchardt said the NRC couldn't possibly devise an ironclad regulation for everything, because not everything can be put to the test.
"It's an issue commissions have struggled with since the first day of the NRC," he said.
It won't be resolved during this hurry-up 90-day review, but it's likely to end up on the table again, when the NRC steps back later this year to take a broader look at how to improve domestic nuclear safety procedures.
Source: http://www.npr.org/2011/05/12/136235601/us-looks-to-reinforce-nuclear-safety?ft=1&f=1007
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