Learning the lessons of Fukushima

Aug 24, 2011 By David L. Chandler
Credit: Christine Daniloff

Among the lessons to be learned from the accident at Japan’s Fukushima Daichii nuclear powerplant, according to a new report from MIT, are that emergency generators should be better protected from flooding and other extreme natural events, and that increasing the spacing between reactors at the same site would help prevent an incident at one reactor from damaging others nearby.

These and other lessons are contained in a report put out this month by MIT’s Department of Nuclear Science and Engineering (NSE), based on its analysis of how events unfolded at the troubled plant in the days and weeks following Japan’s devastating earthquake and tsunami on March 13.

The specific suggestions in this report are quite different from the response by some governments — notably, Germany and Japan, which have halted or delayed expansion of nuclear power in the wake of the meltdowns and radiation releases at the Japanese reactors. In fact, the report says, health risks to the public, and even to workers at the plant, have been negligible, despite the significant releases of radiation over the last few months. There has been no loss of life associated with the accident, nor is there expected to be, the report says.

The new report, an update of a preliminary report issued in May, is available for download on the NSE website.

“A lot of information that was not available when we started has become available,” says Jacopo Buongiorno, the Carl Richard Soderberg Associate Professor of Power Engineering and lead author of the new report, which was co-authored by eight other members of the NSE faculty. However, he adds, there are some important areas where information has still not come out.

During the first days of the accident, he says, there were three critical delays that have not yet been well explained — although the report says there is no evidence at this point of any major human errors contributing to the unfolding problems. The delays involved operating some safety-critical valves, injecting water into the reactor cores and venting the containment buildings. “It’s not clear what the cause of the delays was,” Buongiorno says, but it is unlikely that these were caused by administrative delays in Japan’s control-and-command chain, as had been initially suggested.

Rather, because of the lack of power and the effects of the flooding, “there was disruption and confusion around the site” during the crucial early hours, he says. “Things that normally would take minutes, such as reading an instrument or connecting a cable or a hose, took hours” because of the lack of power and the debris and destruction. “Given the situation, they reacted as well as they could,” he says.

Among the specific suggestions the report makes:

  • Emergency backup generators, needed to keep the systems running when outside power is cut off as it was in this case, should be well separated into at least two locations — one situated high up, to protect against flooding, and the other down low to protect against hazards such as an airplane crash. These generators should also be housed in watertight rooms, as they already are at many U.S. plants.

  • In future plants, spacing between reactor buildings located at the same site should be increased — for example, by having other areas such as parking lots or support buildings in between — and systems such as ventilation shafts should be kept separate, in order to avoid a domino-like spread of problems from one reactor to another. In the accident, it seems that hydrogen vented from reactor unit 3 may have reached unit 4 through the ventilation system, causing an explosion there.

  • Officials should be cautious about decisions to evacuate large areas around a damaged nuclear plant in cases where the population has already been devastated by a natural disaster. At Fukushima, “ironically, the biggest [health] consequences may be from the prolonged evacuation,” Buongiorno says.

  • More attention needs to be paid to how radiation risks are communicated to the public, rather than the confusing mix of different measurements that were disseminated in this case. The most useful standard is to relate radiation releases to natural background levels, rather than using technical units unfamiliar to most people.
Perhaps the most obvious piece of advice — and one that is already observed in the majority of new nuclear-plant installations worldwide — is simply that in siting future plants it would be wise to “choose sites away from highly seismic areas and coasts,” to reduce the risks from earthquakes, tsunamis and floods. For existing plants located in areas at high risk of earthquakes and tsunamis, it is important to re-evaluate the design basis for such extreme natural events, incorporate the latest data and state-of-the-art methodologies in the analysis, and ensure the plants are adequately protected.

But the report also emphasizes that all engineered structures — bridges, powerplants, skyscrapers, dams — have their own risks, especially when subjected to extreme conditions they were never designed to withstand. The authors suggest it is important not to overreact to particular high-profile cases.

“If you have an accident in your car, you don’t stop driving a car, you learn from it,” Buongiorno says. Continuing the analogy, “in this case, the accident was like a tree that fell on the car. It wasn’t the car itself.”

But to fully absorb and learn from the lessons of this accident may take years, Buongiorno cautions. “It took 20 years to fully absorb the lessons of Three Mile Island,” he says. “Some of these questions are complex, requiring quantitative analysis to fully evaluate the data and make rational decisions about how best to respond.”

Romney Duffey, a principal scientist at Atomic Energy of Canada Ltd., says, “This report is both an excellent summary and provides thoughtful suggestions. Of particular importance, the report addresses the links to energy policy and comparative-risk aspects, in addition to the purely technical and licensing considerations.” He adds that the suggestions regarding better public communication about risks from radiation releases are especially useful: “The concept of using easier-to-understand measures of risk is vital to better communicating with everyone during such times of great stress and uncertainty.”

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User comments : 21

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Jeddy_Mctedder
3.9 / 5 (7) Aug 24, 2011
the u.s. and the japanese government will lie to your face , get caught, and then lie about having lied. government persistently lie to protect their corporate sponsors. that's the lesson.
hush1
2.3 / 5 (3) Aug 25, 2011
"However, he adds, there are some important areas where information has still not come out."

This information is like Fukushima's radiation.

The final say in safety is insurance. That is the bottom line to MIT, DOE, and all other pro stances everywhere.

Again. The bottom line is insurance. Are you listening? If insurance companies insure it, it is safe.
No exceptions. No discussion. No debate. Not one word until insured.

Are you listening? I said if insurance companies insure it, it is safe.

Now which power plants do not have insurance? Focus. Stay focused.
Who_Wants_to_Know
not rated yet Aug 25, 2011
@hush1 - I can't speak to other nations, but ALL nuclear power plants in the USA are self insured and use a pooling system for further secondary coverage also. Beyond that there is government indemnity that was put in place decades ago when nuclear power was still very new - it would only come into play under very extreme circumstaces that are far beyond anything likely to occur, beyond even what has occurred at Fukushima. This isn't the only thing the federal gov. insures either - ever heard of flood insurance, which is primary rather than a 3rd level backup as with nuclear power??
hush1
3 / 5 (2) Aug 25, 2011
"...but ALL nuclear power plants in the USA are self insured..." - Who Wants To Know

What does this mean? Self insured?
Where do I find this gov. "indemnity".
Who besides all nuclear power plants insure themselves.
What is the law covering self insurance.

Name one insurance company that insures nuclear power plants.
hush1
3.7 / 5 (3) Aug 25, 2011
http://www.chessk...ccidents

"It is remarkable that all insurance companies have so far refused to insure against nuclear accidents, because they argue that they do not want to risk their money based on some professor's calculations claiming the risk is low. What if he is wrong? Insurance companies insist to base their risk calculations on real experience.

Because insurance companies refuse to cover the risks of nuclear accidents, the Price- Anderson Act of 1957 commits the US federal government to cover such risks. Other countries have similar legislation. This represents an enormous subsidy by the taxpayers to the nuclear industry. If the nuclear power industry were forced by law to pay for insurance against accidents, and pay for the safe disposal of its waste, we would have no nuclear power plants."

The highest resistance I will offer until insurance companies insure nuclear power plants.
hush1
3 / 5 (2) Aug 25, 2011
The highest support I will offer when a insurance company insures nuclear power plants.
The is no discussion. No discourse. No debate. No exceptions. No one word until insured by an insurance company.

Simply state you do not understand.
LuckyExplorer
4 / 5 (4) Aug 25, 2011
If you have an accident in your car, you dont stop driving a car, ..."

There is a small difference between a car accident and nuclear desaster. - The consequences of the second case are much bigger - they concern much more people

and...

if you were carelessly (e.g. driving to fast) hurting others even when the trigger was a falling tree, you will be punished

There is NO insurance for nuclear power plants all over the world, at least no insurance that covers the results of a GAU
Insurence companies don't gamble, they use statistics to earn money.
Magnette
4 / 5 (2) Aug 25, 2011
This is why the nuclear power plants underwrite themselves. It's too specialised an area for any insurance company to take on and it's not unusual for large companies to underwrite themselves.
As an example, London Transport underwrite themselves for all of their London buses as it would be impossible for a seperate company to maintain this themselves. This I know after having one of their buses drive into my car last year.

If you really want to find out about nuclear power plant insurance you could try knocking on their door or have a read here...

http://en.wikiped...d_States
hush1
3 / 5 (2) Aug 25, 2011
"Once the underwriting agreement is struck, the underwriter bears the risk of being able to sell the underlying securities, and the cost of holding them on its books until such time in the future that they may be favorably sold."

http://en.wikiped...rwriting]http://en.wikiped...rwriting[/url]

If you really want to find out about underwriting one's self you could start to have a read here...

http://en.wikiped...rwriting]http://en.wikiped...rwriting[/url]

When can Tepco be favorably sold?
Who_Wants_to_Know
not rated yet Aug 25, 2011
hush1, do you understand the concept of insurance at all? The entire concept is based on spreading the financial risk of something out over time and the group that is in the pool insured.
Who_Wants_to_Know
not rated yet Aug 25, 2011
It's also wrong - twists history and facts - to claim that 'no insurance company will insure commerical power so that's why Price Anderson was inacted.'

Also incorrect to claim that P-A is a huge subsidy as if commercial power plants weren't paying massive amounts of money each year in insurance.

See: http://www.nrc.go...-fs.html
ryggesogn2
5 / 5 (1) Aug 25, 2011
Who is insuring those who lost their cars, businesses and houses to the tsunami?
Who_Wants_to_Know
not rated yet Aug 25, 2011
As to self insurance - there isn't anything the least bit unusual, questionable, or uncommon about it. Companies self insure all the time for all sorts of things, e.g., automotive fleets, health insurance, liability coverage, etc. There are reams of regulations that cover what is required to legally self insure.
Who_Wants_to_Know
not rated yet Aug 25, 2011
@ryggesogn2 - EXACTLY. In effect, to some extent at least, the Japanese federal government (e.g., everyone in Japan), have by default insured those who are still alive but were harmed by the EQ & tsunami.

~20,000 people wiped from existance by the tsunami, 200,000 homes and buildings gone, about 200 tsunami shelters wiped out too along with anyone in them... and people are going crazy over the subsequent nuclear power plant problem that hasn't killed or even injured anyone, and doesn't look likely to either.

It's an easy target for them, but it sure shows a lack of any real perspective.
Who_Wants_to_Know
not rated yet Aug 26, 2011
@luckyexplorer. Actually, if something beyond your control and thru no fault of your own causes you to have an auto accident and someone is injured, you are not punished for it.

Furthermore, your car gets you & maybe a very few passengers somewhere convenient only for you. Nuclear power plants provide energy that benefits literally millions of people for each plant, saves huge numbers of lives, and does so every year for decades. Meanwhile, to help ensure no nuclear plant is 'speeding' or being 'driven recklessly' there is a massive oversight and regulatory system in place.

If you compare lifecycle deaths and injuries, even after you include the few accidents that have happened over 60 decades and around the world, nuclear is still the safest way to generate electricity. Safer even than current day wind or solar or hydro.
hush1
3 / 5 (2) Aug 26, 2011
@Who Wants To Know
Every word wasted here. Do not convince us. Convince an insurance company. Just one. To insure. That alone is the game changer. Anything short of this is lip service.

Simply call all insurance companies stupid for not offering coverage for safe, clean, environmental friendly, future orientated, lucrative, economical fail safe business.

No insurance company in the world is willing bear the risk no matter what the spread.

Find the company. Then post back here. And if you can't find a single company, have all of them tell you why they refuse to insure.
Magnette
2.7 / 5 (3) Aug 26, 2011
@Hush1;
Wow, you really don't understand the principles behind insuring anything like this! It's not just nuclear power stations but, as Who Wants To Know previously stated, there are many styles of large corporations that are self underwritten.

Why do you have a hang up about an insurance company taking on the risk? It makes no difference whether it's an insurance company or they are self underwritten as the rules and regulations that they have to abide by are exactly the same for all liabilities.
Why should an insurance company take on the risk when it's completely unecessary.
It's not a case of refusing to insure, they are not requested to insure.

However, I suspect that, to use your phrasing, every word wasted here as you don't want to take off your blinkers and understand what we are trying to explain to you.
ryggesogn2
5 / 5 (1) Aug 26, 2011
For all you on the east coast, try to buy earthquake insurance. How much is it?
I looked at the cost for earthquake insurance in Las Vegas once and it was VERY expensive.
Bookbinder
5 / 5 (1) Aug 27, 2011
"emergency generators should be better protected from flooding"

No shit, Sherlock!
LuckyExplorer
not rated yet Aug 29, 2011
This discussion about "Learning the lessons of Fukushima" just shows that:

NO LESSON LEARNED!
Who_Wants_to_Know
not rated yet Aug 29, 2011
This discussion about "Learning the lessons of Fukushima" just shows that:

NO LESSON LEARNED!


Yes, it's sad that you are unable to learn and hold onto opinions based on incorrect information. But at least you recognize that about yourself and are willing to admit it. That's a start!