Terrific: Containment vessels used at Japanese plant have long been questioned by nuclear experts; Update: Reactor roof cracked?

posted at 4:14 pm on March 15, 2011 by Allahpundit

Twenty-four hours ago I asked, “How sure are we that the containment vessels at Fukushima can contain a full meltdown?” Twenty-four hours later, the answer appears to be: Not very.

In 1972, Stephen H. Hanauer, then a safety official with the Atomic Energy Commission, recommended in a memo that the sort of “pressure-suppression” system used in G.E.’s Mark 1 plants presented unacceptable safety risks and that it should be discontinued. Among his concerns were that the smaller containment design was more susceptible to explosion and rupture from a buildup in hydrogen — a situation that may have unfolded at the Fukushima Daiichi plant…

A written response came later that same year from Joseph Hendrie, who would later become chairman of the N.R.C. He called the idea of a ban on such systems “attractive” because alternative containment systems have the “notable advantage of brute simplicity in dealing with a primary blowdown.”

But he added that the technology had been so widely accepted by the industry and regulatory officials that “reversal of this hallowed policy, particularly at this time, could well be the end of nuclear power.”

The Mark 1′s containment vessel was smaller than other types of vessels, which made it cheaper and easier to build — but also, in theory, more prone to rupture in the event of a full meltdown. More from WaPo:

In 1986, a top official at the Nuclear Regulatory Commission raised concerns about the GE containment system’s design.

“I don’t have the same warm feeling about GE containment that I do about the larger dry containments,’’ said Harold Denton, director of NRC’s Office of Nuclear Reactor Regulation during an industry conference, according to a report at the time by the publication, Inside N.R.C. “There has been a lot of work done on those containments, but Mark I containments . . . you’ll find something like a 90 percent probability of that containment failing.’’

Not only are these Mark 1 vessels in service at Fukushima, but they’re 40 years old — so old, in fact, that the reactors were going to be retired anyway later this year.

It wasn’t just industry officials who questioned the Mark 1, either. It was some of G.E.’s own technicians:

Thirty-five years ago, Dale G. Bridenbaugh and two of his colleagues at General Electric resigned from their jobs after becoming increasingly convinced that the nuclear reactor design they were reviewing — the Mark 1 — was so flawed it could lead to a devastating accident…

“The problems we identified in 1975 were that, in doing the design of the containment, they did not take into account the dynamic loads that could be experienced with a loss of coolant,” Bridenbaugh told ABC News in an interview. “The impact loads the containment would receive by this very rapid release of energy could tear the containment apart and create an uncontrolled release.”

But wait. There’s been no confirmed containment rupture (yet) at Fukushima, notwithstanding last night’s massive but temporary spike in radiation near the plant. All six containment vessels at the plant withstood a 9.0 earthquake and dozens of significant tremors; three of them have also withstood hydrogen explosions in the buildings they’re housed in, albeit with some damage to the suppression pool in reactor number two. And according to G.E., there’s never been a breach — ever — of any Mark 1 containment vessel since they were first introduced. So what gives? More from ABC:

Bridenbaugh told ABC News that he believes the design flaws that prompted his resignation from G.E. were eventually addressed at the Fukushima Daiichi plant. Bridenbaugh said GE agreed to a series of retrofits at Mark 1 reactors around the globe. He compared the retooling to the bolstering of highway bridges in California to better withstand earthquakes.

“Like with seismic refitting, they went back and re-analyzed the loads the structures might receive and beefed up the ability of the containment to handle greater loads,” he said.

He thinks the Mark 1 may be “still a little more susceptible to an accident that would result in a loss of containment,” but those retrofits might have been the difference between a frightening-yet-smallish radiation leak and a sustained radioactive belch. Or maybe I’m wrong; maybe the heroic nuclear techs still on the scene at Fukushima, against all odds, have actually managed to prevent a significant meltdown in each of the reactors thus far, in which case the containment vessels haven’t — yet — been put to the ultimate test. The longer this goes on, though, and the more sea water is flushed to the core, the cooler it gets and the less steam is produced, which means the risk of a rupture due to pressure build-up should be declining by the hour. That’s assuming, of course, that they’re still able to get sea water in there. Are they? Quote:

A senior nuclear industry executive who insisted on anonymity said that a compromised suppression pool [in reactor number two] made it much harder to bleed high-pressure steam from an overheating nuclear reactor so as to pump more seawater into it. “How are you going to bleed into something that has got a big hole in it?” he said.

Mr. Friedlander was more optimistic, saying that the rupture in the primary containment building was much more likely to have occurred above the water line of the suppression pool than below it. “The likelihood is that it is still holding water,” and so can be used for some venting of vapor from the reactor, he said.

Believe it or not, reactor two isn’t even the biggest crisis they’re facing right now. Potentially, that’s the spent fuel rods that have started to boil in a rooftop storage pool that’s lost water. If those start to melt, you’ll get the same sort of radioactive release as you would from a containment vessel breach. A Japanese source quoted in that last Times link says they have just a single day to do something about it, or possibly two, and they’re so desperate that they may send helicopters to try to douse the rods from above. I wonder, though, if the rods have already started to melt: This ominous report from Reuters timestamped at 2:43 p.m. says Japanese officials admit that radiation is now being released directly into the air without saying precisely why. Presumably it’s due to the spent fuel rods and not a containment vessel rupture; either way, the leak is significant enough to drive radiation levels around the plant up to 400 millisievert per hour. For comparison purposes, cancer has been linked to levels of 100 millisievert per year. What that means for Tokyo, if those radiation levels don’t start to drop seen, I can’t begin to imagine.

Exit question: If there’s a meltdown and the Mark 1 breaches, what happens if the core ends up in the area’s water table?

Update: A bulletin from Reuters:

FLASH: Japan nuclear safety agency says Fukushima No. 4 reactor roof is cracked

By “reactor roof,” do they mean the containment vessel itself or merely the building in which number four is housed? Losing the building is no big deal. Losing the vessel would be … oh boy. Stand by for updates.

Update: What will happen to Tokyo?

Toxicologist Lee Tin-lap at the Chinese University of Hong Kong said such a radiation level was not an immediate threat to people but the long-term consequences were unknown.

“You are still breathing this into your lungs, and there is passive absorption in the skin, eyes and mouth and we really do not know what long-term impact that would have,” Lee told Reuters by telephone…

“The possibility of further radioactive leakage is heightening,” a grim-faced Kan said in an address to the nation earlier in the day.

Update: Reuters clarifies: It’s the reactor building whose roof is cracked, not the containment vessel. Whew.


Related Posts:

Breaking on Hot Air

Blowback

Note from Hot Air management: This section is for comments from Hot Air's community of registered readers. Please don't assume that Hot Air management agrees with or otherwise endorses any particular comment just because we let it stand. A reminder: Anyone who fails to comply with our terms of use may lose their posting privilege.

Trackbacks/Pings

Trackback URL

Comments

Comment pages: 1 2

This is all not good and all, but you have to admire the luck of Obama.
Problem and problem around the world, he does nothing and yet is taken of the hook for inaction on any problem because there is a NEW problem that takes the headlines and everyone forgets about the previous problem he was doing nothing on.

albill on March 15, 2011 at 8:01 PM

At this level probably statistically insignificant but it’s effectively blanketing the entire country and as the levels go up more people will be affected.

gh on March 15, 2011 at 7:56 PM

We don’t know the long term impact. If it is washed away with the next rain, then it won’t have much impact. If it settles on farmland or coats buildings and doesn’t go away, it could cause some increase in cancer and big economic problems.

pedestrian on March 15, 2011 at 8:07 PM

We don’t know the long term impact. If it is washed away with the next rain, then it won’t have much impact. If it settles on farmland or coats buildings and doesn’t go away, it could cause some increase in cancer and big economic problems.

pedestrian on March 15, 2011 at 8:07 PM

It is true we don’t know the long term impact because the situation is not yet stable. However, the entire population has already received a small dose through inhalation. Just look at a map (there’s one in the article) to see how far away Tokyo is from the reactor and the background levels have already gone up in Tokyo by a factor of 10. I assume that they have probably peaked and gone down but another release could send them higher.

gh on March 15, 2011 at 8:13 PM

Lube Oil system.

No, I’m not a genius just saw a report earlier this morning that the first fire there was caused by a Lube Oil system.

Was it actually true? Hell – who knows! Sounds good though huh?

HondaV65 on March 15, 2011 at 7:24 PM

That sounds about right.

Our reactor coolant pumps had large oil reservoirs on the motors. Enough oil that they had their own dedicated fire detection systems, big big electrical motors. Don’t know how much oil BWR recirc pumps hold but it’s probably enough to be a credible fire hazard.

Oldnuke on March 15, 2011 at 8:21 PM

Lube Oil system.

The gets back to the problem of having to run on a reduced number of operators who are all directly involved in cooling the reactors. God bless the people who are willing to still work there, but all kinds of secondary systems are going to be having maintenance issues in the wake of continuing earthquakes, the tsunami, multiple explosions, and now fires.

pedestrian on March 15, 2011 at 8:26 PM

grtflmark

has his act together. Great description of zirc/water reaction.

Oldnuke on March 15, 2011 at 7:06 PM

Yeah, he was pretty sharp, wasn’t he? He has two reactor certifications and some radiation health job also.

Welcome to the team. If you like the site, hang around.

I had to go home to get some food. Something many Japanese can’t do right now. I’d say when they start really starving the politeness and order will start breaking down. We owe them food before that happens.

Subsunk

Subsunk on March 15, 2011 at 8:35 PM

Our reactor coolant pumps had large oil reservoirs on the motors. Enough oil that they had their own dedicated fire detection systems, big big electrical motors. Don’t know how much oil BWR recirc pumps hold but it’s probably enough to be a credible fire hazard.

Oldnuke on March 15, 2011 at 8:21 PM

Fires on lube systems are not real common but do happen and in the environment that they are dealing with it’s not hard to believe.

whbates on March 15, 2011 at 8:36 PM

WNN reports the response on this recent fire was delayed due to high radiation levels in the plant. However – it appears there WAS a response to it …

I still think the term “high levels” is “high” in the western sense – not the soviet sense – LOL!

In other words – I think they’re doing everything they can to ensure that casualty responders receive “within acceptable levels” exposure. At Chernobyl, for instance, it appears some people tried to be “heros” and paid a heavy price early on.

HondaV65 on March 15, 2011 at 8:40 PM

A couple of new facts here:

Japanese Officials Scramble to Contain Nuclear Power Plant Crisis

Published March 15, 2011 | FoxNews.com

Japanese officials are scrambling to find ways to contain radiation leaks and combat deteriorating conditions at the troubled Fukushima Dai-ichi nuclear power plant, which was damaged by the country’s devastating earthquake and tsunami.

The country has ordered a nearby 140,000 people to seal themselves indoors after a series of explosions and fires at the plant. The latest fire, at the plant’s No. 4 reactor, is under control, according to Tokyo Electric Power Co., the owner of the facility, which blamed it on an earlier fire that hadn’t been fully extinguished.

The company also reported that damage to the fuel rods at the No. 1 and No. 2 reactors were 70 and 33 percent, respectively.

Officials said radiation levels in areas around the nuclear plant rose early Tuesday afternoon but appeared to subside by evening.

Early Wednesday, Japan abandoned plans to spray water from helicopters into an overheating spent fuel storage pool at the facility. A TEPCO spokesman said that helicopters were deemed impractical, but other options were under consideration, including fire engines. There were later reports that a boric acid drop was being considered.

The International Atomic Energy Agency has established a 19-mile no-fly zone around the plant’s perimeter — a move that comes as the U.S. Navy said Tuesday they detected low levels of airborne radiation at Yokosuka and Atsugi bases, 200 miles away from the nuclear plant, according to Newscore.

“We have received so [much] support from across the globe,” said Noriyuki Shikata, the Japanese prime minister’s spokesman, to Fox News’ Bret Baier on Special Report. “U.S. forces in Japan have been actively been helping the Japanese people.”

Fox News has confirmed that a small number of U.S. service members have been exposed to radiation Tuesday and are being treated with potassium iodide pills. A U.S. military official says the risk is manageable.

“While there was no danger to the public, Commander, Naval Forces Japan recommended limited precautionary measures for personnel and their families on Fleet Activities Yokosuka and Naval Air Facility Atsugi, including limiting outdoor activities and securing external ventilation systems as much as practical,” a U.S. Navy statement said.

………………

“People have been mobilized along with police, coast guards and fire fighters,” Shikata said. “We are doing the upmost efforts to save lives and rescue people.”

Japanese officials told the IAEA that the reactor fire was in a storage pond and that “radioactivity is being released directly into the atmosphere.” Long after the fire was extinguished, a Japanese official said the pool, where used nuclear fuel is kept cool, might be boiling.
(this seems like one hand doesn’t know what the other is doing)

“We cannot deny the possibility of water boiling” in the pool, said Hidehiko Nishiyama, an official with the economy ministry, which oversees nuclear safety.

The IAEA’s head, Yukoiya Amano, urged the Japanese government to provide better information to the agency about the situation.

Experts monitoring the troubles at the plant say a lot of the radiation that’s been emitted has apparently come in steam from boiling water — instead of directly from fuel rods, which would be much more dangerous

Kyodo News reports that the plant was unable to pump water into Unit 4 reactor’s storage pool for spent fuel. That reactor had been shut down before the quake for maintenance.

The IAEA says an explosion at the Unit 2 reactor may have damaged the main containment vessel.

“After explosions at both units No. 1 and No. 3, the primary containment vessels of both units are reported to be intact. However, the explosion that occurred … at the Fukushima unit No. 2 may have affected the integrity of its primary containment vessel. All three explosions were due to an accumulation of hydrogen gas,” the IAEA said in a statement.

If the water boils, it could evaporate, exposing the rods. The fuel rods are encased in safety containers meant to prevent them from resuming nuclear reactions, officials said, downplaying the risk of that happening.

But they acknowledged that there could have been damage to the containers. They also confirmed that the walls of the storage pool building were damaged.

…………

The radiation fears added to the catastrophe that has been unfolding in Japan, where at least 10,000 people are believed to have been killed and millions of people have spent four nights with little food, water or heating in near-freezing temperatures as they dealt with the loss of homes and loved ones. Up to 450,000 people are in temporary shelters.

……….

Temperatures in at least two of the complex’s reactors, units 5 and 6, were also slightly elevated, Edano said.

(These reactors were shutdown BEFORE the earthquake and the only threat of them melting down is if the crews pay no attention to their actual temperatures.)

“The power for cooling is not working well and the temperature is gradually rising, so it is necessary to control it,” he said. (Duh, there is no power except for the generators brought it after the tsunami. This brings to mind the conditions the crew is facing. No lights in their engineering spaces. Probably just lights in the control rooms and in the equipment spaces where the pumps are. I doubt full lighting is available. It is hot in there, and they are probably dog tired. How the Hell do you think you would hold up?)

Fourteen pumps have been brought in to get seawater into the other reactors. They are not yet pumping water into Unit 4 but are trying to figure out how to do that.

In Tokyo, slightly higher-than-normal radiation levels were detected Tuesday but officials insisted there are no health dangers.

“The amount is extremely small, and it does not raise health concerns. It will not affect us,”
Takayuki Fujiki, a Tokyo government official said.

………….

Kyodo reported that radiation levels nine times higher than normal were briefly detected in Kanagawa prefecture near Tokyo and that the Tokyo metropolitan government said it had detected a small amount of radioactive materials in the air.

Edano said the radiation readings had fallen significantly by the evening.

With snow and freezing temperatures forecast for the next several days, shelters were gathering firewood to burn for heat, stacking it under tarps and tables.

In North America, two Japanese automakers — Subaru and Toyota — are halting some production at factories to assess availability of car parts following the damage in Japan.

http://www.foxnews.com/world/2011/03/15/japanese-nuclear-panic-rises-agency-says-radiation-leaking-atmosphere/

Subsunk on March 15, 2011 at 9:37 PM

If not now, when? When the media has everybody whipped up in a panic about a different imagined doom scenario?

Slowburn on March 15, 2011 at 7:27 PM

When the plant is not so radioactive that people can actually come within 20km without protective gear?

pedestrian on March 15, 2011 at 7:43 PM

It is a forty year old plant, that a record earthquake, followed a record tsunami damaged. There are other industrial plants that if they would have taken the same level of damage thousands would all ready be dead. Nobody is suggesting that we give up fertilizer, pesticides, and plastics because of the danger of an industrial accident. Union Carbide anybody.

Slowburn on March 15, 2011 at 10:59 PM

Allahpundit, you write, “For comparison purposes, cancer has been linked to levels of 100 millisievert per year.”

I note for another comparison that levels of 260 millisievert per year have been associated with better health and longer lives. The background radiation at Ramsa Iran is purported to be about 260 millisieverts per year. And as this Wikipedia article cites the people there seem to have, if anything, healthier and longer lives. Experts are at a loss to explain it except to note the “linear no-threshold model” used to justify extremely low exposure limits may be just a bit off the mark.

That aside, be sure you are not allergic to Iodine AND are not on a medication that tends to minimize the body’s elimination of potassium, such as some diuretics and heart medications. Too much potassium kills. (So does too little potassium.)

{^_^}

herself on March 16, 2011 at 3:12 AM

I’ll post again:

As former NRC licensed senior reactor operator, I worry about the reporting on the Japanese nuclear incident.

Supposedly there is no breach of primary containment (the vessel) but there have reportedly been hydrogen explosions, limited release of radioactive isotopes and high background radiation levels. In boiling water reactors (BWRs) steam is DIRECTLY piped from the reactor to the turbine to produce electricity. Steam piping penetrates the drywell
(secondary containment) surrounding the reactor. The rectangular building over the turbine, generator, reactor and support equipment is not a containment for major nuclear incidents but can contain the normal slightly radioactive steam sent to drive the turbine.

So any hydrogen produced in the core, as well as radioactive Iodine 131 and other radioactive isotopes in a collapsed core produced by the previous fission process, can escape into the building if the steam piping
is damaged and cannot be isolated by the steam shut off valves. So if hydrogen is the source of the reported explosions, the vessel is effectively open to the damaged building via the steam piping penetrations and radioactive isotopes can escape to the surrounding area.

A secondary concern is the spent fuel pool inside of the building. If the spent fuel is uncovered, the fuel could overheat and fail, releasing radioactive isotopes.

Reports indicate the tsunami destroyed the emergency diesel generators’ fuel storage tanks preventing continued long term operation of the emergency cooling systems, which would have most likely prevented this
catastrophe.

I believe the fuel tanks are seismic qualified, so the concern should be the probability of a tsunami causing similar damage to curtail the operation of the emergency diesels at an American facility. Why the Germans shut down seven of their reactors is beyond me. What’s the probability of all this happening somewhere outside of Japan?

amr on March 16, 2011 at 9:11 AM

To all you Democrats that think Obama is god. Why is this happening? Why hasn’t he just raised his hands and made all this stop. So I guess we can blame all this on you people and obama.

BruceB on March 16, 2011 at 10:20 AM

Comment pages: 1 2