By Tuan Nguyen
Posting in Design
The U.S. has in operation the same type of reactor that's dangerously veering toward a possible meltdown.
In light of the disastrous unraveling of Japan’s nuclear facilities, the Obama administration moved swiftly to reassure an anxious public that reactors in the United States are safe.
“The American people should have full confidence that the United States has rigorous safety regulations in place to ensure that our nuclear power is generated safely and responsibly,” Energy Secretary Steven Chu told the House of Representatives Appropriations Subcommittee on Energy and Water Development.
He also added that officials are “committed to learning from Japan’s experience as we work to continue to strengthen America’s nuclear industry.”
But for skeptics, what’s particularly worrisome is the fact that the U.S. has in operation 23 General Electric Mark 1 nuclear reactors, the same type of reactor that’s dangerously veering toward a possible meltdown. And a report in the New York Times has uncovered decades-old memos from high-ranking energy officials that warned of flaws in the reactor’s containment vessel, a structure that serves as the last line of defense in case the cooling system malfunctions.
In 1972, Stephen H. Hanauer, a safety official with the Atomic Energy Commission wrote up an an assessment of the Mark 1’s containment design and recommended that the agency adopted a policy “discouraging the use of such “pressure-suppression containment” and that such a design “not be accepted for construction permits” for the time being.
Joseph Hendrie, who later served as the chairman of the Nuclear Regulatory Commission, acknowledged that Hanauer’s proposed course of action was “attractive,” but decided against moving forward with the suggestions. His reasoning was that “reversal of this hallowed policy, particularly at this time, could well be the end of nuclear power.”
At the time, nuclear energy was still trying to gain footing as an alternative to oil and GE opted for a comparably smaller containment vessel design because it allowed for cheaper and easy-to-build reactors.
The New York Times report goes on to say:
Questions about the G.E. reactor design escalated in the mid-1980s, when Harold Denton, an official with the N.R.C., asserted that Mark 1 reactors had a 90 percent probability of bursting should the fuel rods overheat and melt in an accident. A follow-up report from a study group convened by the commission concluded that “Mark 1 failure within the first few hours following core melt would appear rather likely.”
In an extreme accident, that analysis held, the containment could fail in as little as 40 minutes.
In reaction to what they company felt was unwarranted finger-pointing, GE issued a statement defending the Mark 1 reactor as “the industry’s workhorse with a proven track record of safety and reliability for more than 40 years.” The company also pointed out that “there has “never been a breach of a Mark 1 containment system.”
To be fair, Mark 1 reactors in the U.S. have since been retrofitted with a series of safety enhancements to compensate for potential vulnerabilities. These features include a venting system and modifications to the torus, a water-filled vessel used to reduce pressure build-up in the reactor.
Also, It’s debatable whether a bigger, studier containment vessel would have fared any better in the face of a tsunami or any other devastating natural disaster.
So for now, many signs seem to indicate that nuclear technology will continue to have a vital role helping to fuel America’s rapidly growing energy needs.
Photo: U.S. Bureau of International Information Programs
Related on SmartPlanet:
- A meltdown-proof nuclear reactor may alleviate fears
- China to develop a greener nuclear reactor
- France’s latest green idea: underwater nuclear reactors
- Japan’s partial meltdowns and the future of nuclear power in the U.S.
Mar 15, 2011
As Noted by "Passingwind" it was the Standby Diesel Power Plants that were disabled by the Tsunami, which ultimately caused the release. The plant was designed for the conditions specified, but, unfortunately the earthquake and Tsunami didn't read the spec's are exceeded them. It's poor consolation but everything is designed to some upper limit: bridges, high-rise buildings and chemical plants. If we choose to have these things and live or work in them we have to accept there are always risks. People used to understand this but unfortunately Lawyers have changed the perception that after an accident "Somebody" is always to blame. That's how they make their living. We have the right and responsibility to set laws governing the design limits and when we do we set the "risks" we as a people as willing to accept. "Only" when it is proven that a person or company willingly violated these should we be righteously inflamed. As an example: We know, both by our scientists and from many movies that there is a real risk of annihilation by meteoroid strike. We have some ability to both monitor for these and with enough foreknowledge, do something about it. We actually started to do a study of the sky and plan for cureative measures but funding has been reduced and a press release made not long ago that "All is safe" "Don't worry" but no logical explanation for it. Why, because people don???t want to know and worse, don't want to pay for a program to protect themselves. just wait for the lawyers to get involved if there is a strike (and earth survives) The "real and present danger": are chemical plants and worse, the rail cars shipping this stuff around and through your neighborhood (Remember Bhopal?) People have become accustimed to these and don't seem to worry. Statistically though that is where the real likelyhood of mass casulties is in the USA but most are blissfully unaware of it. Cities that have these plants or where rail cars pass through have plans for which way the wind is blowing during an"accident" and the number of deaths that WILL occur. Just ask your city planners.
"a proven track record of safety and reliability for more than 40 years" Don't you just love lucky people. The other kind always bring such bad news. Oh - by the way, the tsunami merely disabled the backup power supply the system depends on to avoid meltdown. It could equally well have been any other careless accident causing a site-wide blackout, leading to a similar crisis. You don't need an earthquake.