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Today's MSNBC report on U.S. nuclear risks misinterpreted government data and overstated realistic risks by as much as two orders of magnitude. For example the site stated that the Indian Point 3 reactor (pictured) had a 1 in 10,000 chance of core damage from an earthquake. The actual estimate is one in 670,000.  (Source: Mike Segar / Reuters)

Misinformed by the media, many in the public are stocking up on radiation pills and suggesting banning nuclear power.  (Source: FOE Europe)

The Japanese government is also releasing contradictory and alarming information. According to its latest statement no cores have been breached, so there's no immediate danger to the population, even in this "worst case" scenario.  (Source: The Times)
Fear, uncertainty, disinformation -- news sites offer misinformation, speculation on nuclear power for profit

The nuclear crisis in Japan is bringing international attention.  And there's plenty of misinformation based on current media reports.  We wanted to examine a couple of the top reports circulating, including a report on the risk of a similar disaster occurring in the United States.

I.  Is the U.S. at Risk?  Do You Want the Truth?

Are you at risk of a quake breaking a nuclear plant's core containment vessel and exposing you to potentially cancer-causing levels of radiation?  Yes. 

You are also at risk of dying from lightning, getting mauled by a pig, killed by falling coconut, and all myriad of other unforeseen, unlikely events.

But according to a joint U.S. Nuclear Regulatory Commission (NRC) and U.S. Geological Survey(USGS) report (PDF), the odds of that happening are extraordinarily low.  Risk, after all, is an assessment of uncertainty -- not a prediction that something will happen.  There's plenty of catastrophic but incredibly unlikely risks we face on a daily basis -- the chance of plant damage in the U.S. is one of them.

The report, which is gaining a great deal of attention in the wake of the Japanese incident, should be considered reassuring, if anything.

According to the report, the greatest risk any plant in the U.S. faces is 1 in 10,000 risk of core damage per year at the perfect frequency.  Note this is the probability of core damage, not "large early release" (LER) -- a completed release of radiation into the environment.

MSNBC.com did an excellent job digging up the document.  Unfortunately, from they made numerous factual mistakes in interpreting it.

First, their report offers the hyperbole:

It turns out that the U.S. Nuclear Regulatory Commission has calculated the odds of an earthquake causing catastrophic failure to a nuclear plant here. Each year, at the typical nuclear reactor in the U.S., there's a 1 in 74,176 chance that the core could be damaged by an earthquake, exposing the public to radiation. No tsunami required. That's 10 times more likely than you winning $10,000 by buying a ticket in the Powerball multistate lottery, where the chance is 1 in 723,145.

First, all statistic chances are not created equally.  There are 104 commercial nuclear power plants in the U.S. (69 pressurized water reactors and 35 boiling water reactors).  That means there's roughly 1 in 742 chance per year of core damage -- or roughly 1 in 7.4 chance per century of such an incident at a single plant.  

By contrast there are dozens of $10,000 "Powerball multi-state lottery" winners every year and will likely be thousands of winners per century.  Thus the comparison itself is a bit puzzling.

But the error runs far deeper.

Note, the report says that the risk is of "the core being damaged by an earthquake, exposing the public to radiation".  But as we mentioned earlier, that's not what the report says.  The report references the risk of core damage, which does not estimate the actual probability of a "large early release" of radiation at all.  As the report says, in the case of core damage, such a release would be a "possibility", but given additional containment measures, would likely be a far lower probability than the cored damage frequency (CDF) estimate.

In other words, the report does not predict the risk of the public being exposed to radiation directly at all.

And the errors continue.  The MSNBC report offers a list of plant yearly risks, compiled in handy text format online and in the form of an Excel document.  These risks were taken from the report, but they were the risks at a specific earthquake frequency.  

For example the most "at risk" plant -- New York's Indian Point 3 plant -- has a 1 in 10,000 annual risk of core damage if an ultra-powerful 10 hz earthquake were to strike (thus this is dubbed the "maximum risk" or "weakest link" model).  The actual risk is far lower.  The report gives what is likely the most accurate estimate in the form of a weighted average.  For example for Indian Point 3, the risk is 1 in 670,000 per year.

Now consider the difference between 1 in 10,000 to 1 in 670,000.  We've now gone from 1 in 100 chance of quake core damage per century to 1 in 6,700.  

Looking at the actual numbers, this means that the conclusions goes from there would be likely one core damage at a single plant in the U.S. over the next millennia, to that there would likely be none.

II.  So Reports are Sensationalized -- Why Should I Care?

Now it would be far too easy to cast a blind eye to this kind of misinformation.  All news sites and networks make errors.  But the problem is that in the wake of the earthquake the media has seized on this topic with particular sensationalist fervor and offered much speculation and hyperbole.

The net result is that the U.S. public is becoming mistrusting and fearful of nuclear power.  Anecdotal evidence of that is given by the run on radiation pills in the U.S.

This could have a tremendous deleterious effect on the energy future and security of the U.S.  Nuclear power in the U.S. is arguably the cheapest and most tested form of alternative energy.  The U.S. contains many rich deposits of uranium and other fissile isotopes -- enough to drastically reduce the reliance of the U.S. on fossil fuels from volatile foreign sources.

But public fear can and does have a number of direct effects that may sink that effort.  First, past efforts to build plants in the 1970s and 1980s led to massive lawsuits that raised costs of construction so high that no new U.S. plants were even seriously considered until a year or two ago.

Finally, the U.S. has its first new plant application in three decades and is preparing to embark on a new era of nuclear energy.

It is important to also consider that fission power is widely viewed by the scientific community as only a stopgap solution that at most will be used for power generation for a couple more centuries before being replaced by fusion power.  Nature shows us that fusion is a far more abundant and lucrative source of energy in our universe, so if we can't harness fusion power within 300 years we've done something wrong, given how close we seemingly are.

In other words, nuclear power is a short-term solution and thus risk should only be considered in the short term (as discussed above).

Further, the risks on these new plants will be orders of magnitude less and that they will produce less nuclear waste and more energy.

And last, but not least any discussion of risks should put things in perspective by providing information on equivalent dangers of fossil fuel power generation -- something virtually none have done.  As underscored by the recent coal mining disasters in Chile and West Virginia, fossil fuel power is hardly safe and human friendly.  Every energy source has a cost.  For some alternative energy sources like solar and wind, that cost is high production costs.  For fossil fuels, it's loss of life.  In total 6,400 people died between 1970 and 1992 during coal mining operations, and 1,200 died extracting natural gas [source].

The importance of the truth and accuracy in this situation cannot be overstated.  It is of the utmost importance that the media offers accurate information to the public in countries with nuclear interests, particularly in the wake of the Japanese incident.

III.  Confusion in Japan

MSNBC.com and other news organizations are not solely responsible for the confusion and misinformation that's permeating all news outlets.  Some of it is coming from those who should be reassuring, not speculating -- the government of Japan.

Japan's Fukushima nuclear plants still face a precarious situation in the wake of the record-setting 9.0 magnitude Sendai earthquake.  Smoke has been billowing up from southern Fukushima I's reactor three -- steam from a damaged roof.  Now that smoke is steam from broken water pipes in the cooling system of the reactor building.

Japanese officials on earlier today in a report [PDF] suggested that the reactor core may have been released and that radiation could be carried in the steam into the environment endangering the public.  But then later in the day, they said that the core was not compromised.

Of course by then a score of outlets had already reported that it was compromised.

Similarly, many reports stated that the reactor rods had "melted down" -- a serious problem.  These reports are based on statements made by Japanese officials that the rods may have melted.  There is some evidence of this conclusion -- water was observed to have boiled off of some of the rods, leaving them uncooled.  But officials don't know or haven't released to what extent the rods have melted.

The levels inside the most radioactive plant reached approximately 6.4 millisieverts per hour, before dropping.  To put this in context, a full chest CT scan gives you 7 millisieverts [source] of radiation.  In other words, you could work in the most damaged plant with no protective gear and only receive the amount of radiation of a common medical procedure.  Now that's absolutely not to say that there aren't more serious risks if certain possibilities play out, but the risk of loss of life from the nuclear accident just isn't there yet.


Ultimately, the fault for these confusing and contradictory reports rest largely on the shoulders of Japan's government and international regulators. They have cooperated to publish contradicting and overly speculative reports.

IV. Conclusions

The situation in Japan is ongoing.  Officials are using helicopters and fire-trucks to spray water, and possibly boric acid to cool the smoldering cores.  We won't have the final picture of what -- if any -- significant long-term radiation release the reactors will create for some time now.

If the media wants a sensational story, they can get some great coverage of the efforts to contain the overheating rods.  But in the interest of accuracy they should beware or offer disclaimers on the statements of government officials, given their contradictory track record.  And they should most definitely avoid going out of their way to create more misleading statements themselves by misinterpreting obscure U.S. government reports.



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LOL
By blppt on 3/16/2011 3:30:02 PM , Rating: 2
I think its pretty amusing that this plant was assaulted by a 9.0 earthquake + tsunami, had a reactor building blow up, lose ALL water in the core of one of the reactors for several hours, had significant fuel melts in two reactors, boiling spent fuel pools, and an apparent breach in one of the containment vessels, random fires, etc. and NOBODY has died because of the plant yet. Nor has there been any *HUGE* release of radiation.

I mean seriously, what more can you ask of a nuclear plant than this? What has happened is so far beyond the realm of design safety for NPPs it is ridiculous, and STILL we have yet to see anybody killed from this.

AND this plant consists of cores with dated reactor designs from the 60s-70s. Without many of the advances in safety since then.




RE: LOL
By HoosierEngineer5 on 3/16/2011 3:59:45 PM , Rating: 2
Don't forget that it seems somebody forgot to gas up one of the generators...


RE: LOL
By omnicronx on 3/16/2011 5:13:38 PM , Rating: 2
The backup generators were flooded by the tsunami and had no protective measures for flooding. (not encased or anything).

This is the one thing I thought was terribly mishandled. Not only should someone have had the foresight to at least try and protect the backup generators from water, there was no backup for the backup.

I'm sorry but the cooling system is clearly the biggest source of concern in a nuclear power station, there should have been several levels of redundancy.


RE: LOL
By Solandri on 3/16/2011 7:23:38 PM , Rating: 2
quote:
The backup generators were flooded by the tsunami and had no protective measures for flooding. (not encased or anything).

IIRC, they were built to withstand a 6 meter tsunami because that's the biggest one that had been recorded in Japanese history. Unfortunately, this one was about 8 m. The same thing happened in all the towns which were washed away. They had 4.5-6 m tsunami walls. The tsunami just washed right over them. The videos you've seen of what looks like boats going down a mini-waterfall onto a street? That's the water spilling over the tsunami walls.

quote:
This is the one thing I thought was terribly mishandled. Not only should someone have had the foresight to at least try and protect the backup generators from water, there was no backup for the backup.

I'm sorry but the cooling system is clearly the biggest source of concern in a nuclear power station, there should have been several levels of redundancy.

There were several levels of redundancy. Normally they get power off the grid. The backups are the generators (which were quadruply redundant*). The level of backup were batteries, which they used but only lasted about 8 hours. The next backup was a waste-heat generator, probably something like a stirling engine. For some reason that didn't work. The last backup is getting external power from a generator mounted on a vehicle, but word is they could get the cables to connect properly. So they had to resort to venting steam to cool the cores.

So really you had a huge confluence of unfortunate circumstances. Whether that was just bad luck, or due to negligence in design, or poor maintenance remains to be seen.

*The quadruply redundant diesel generators is a common error when building risk-tolerant systems. Too often the thinking goes "Well, if there's a 10% chance of a generator failing, we'll just put 4 generators there. That way the chance of all four generators failing is 0.1^4 = 0.01%. So it's 99.99% likely to work." Unfortunately, that calculation assumes the failures are independent events. As we saw, the same factor which takes out one generator can take out all the others.

The same thing happened on the space shuttle Challenger. They knew when assembling the SRB segments, there was about a 1 in 100 chance of not mounting it properly and causing a hot spot. So they put in o-rings to seal against that. The o-rings were difficult to mount properly in their seatings, and were known to fail about 1 in something like 100 times. That resulted in a chance of failure of 1 in 10,000 which was too high. So they figured they could just put in 2 o-rings. Even if one failed the chances of both failing would be 1 in 10,000. That put the chance of complete failure at 1 in 1 million, which they deemed to be safe.

They completely missed that a factor (cold weather) could guarantee both o-rings would fail. (Well, apparently the engineers knew it, the managers just refused to believe them.)


RE: LOL
By Donkeyshins on 3/16/2011 8:32:42 PM , Rating: 2
You are also failing to mention that the first reactors to have problems were 40-year-old reactors based upon the GE Mark 1 design and were scheduled to be retired in February of this year (until TEPCO lobbied to extend the life of the reactors by a decade). If these had been a Gen III or Gen III+ design, we most likely wouldn't be having this conversation as there wouldn't have been a loss of coolant.


RE: LOL
By Breakfast Susej on 3/16/2011 4:05:12 PM , Rating: 2
What's sad is what should be a testament to the incredible safety of nuclear power is being hovered over by the anti nuclear fanatics, not unlike a vulture hovering over a corpse.

Ironically though as you say, there isn't even a corpse involved.

Those looking to twist the admirable performance of the Japanese into a talking point in their anti nuclear agenda should really be ashamed.


RE: LOL
By bh192012 on 3/16/2011 5:51:07 PM , Rating: 3
"A seriously injured worker who had been trapped in the crane operating
console of the exhaust stack was transported to the ground at 5:13pm and
confirmed dead at 5:17pm." http://www.tepco.co.jp/en/press/corp-com/release/1...

Although I'm not sure of the cause of death. I believe it has been labled a crane accident. Does that count? Doesn't sound nearly as impressive as all the other stuff you mentioned. Maybe we should be lobbying for safer cranes, the true menace at nuclear plants.


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