Three Mile Island Shuts Down After Pump Failure

SchrodingerZ writes "The nuclear power station on Three Mile Island in Pennsylvania shut down abruptly this afternoon. Its shutdown was caused when one of four coolant pumps for a reactor failed to work. 'The Unit 1 reactor shut off automatically about 2:20 p.m., the plant's owner, Exelon Corporation, reported. There is no danger to the public, but the release of steam in the process created "a loud noise heard by nearby residents," the company said.' If radiation was released into the environment, it is so low that it thus far has not been detected. The plant is a 825-megawatt pressurized water reactor, supplying power to around 800,000 homes, thought there has been no loss of electrical service. Three Mile Island was the site of a partial nuclear meltdown in 1979. The Unit 2 reactor has not been reactivated since."

Comments

And, cue shitstorm..

[Anonymous Coward]

But, to be fair, isn't this how these things are suppose to work? Something fails, everything gracefully shuts down?

Re:And, cue shitstorm..

[fredgiblet]

Yes.

Not that that's going to stop the shitstorm

Re:And, cue shitstorm..

[Black Parrot]

Yes.

Not that that's going to stop the shitstorm

Clearly, we need more backup pumps for shitstorms.

Re:And, cue shitstorm..

[Anonymous Coward]

The internet has an infinite supply, no worries.

Re:And, cue shitstorm..

[Anonymous Coward]

Yep. Basically, everything worked as it was meant to. Problem will be fixed soon and life will continue as usual.
Also, if one wishes to scare greenies half to death: http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2012/

Re:And, cue shitstorm..

[Anonymous Coward]

It doesn't sound like a graceful shutdown. We'll have to wait for the NRC event report tomorrow. A reactor cooling pump trip would typically initiate a reactor protection trip (scram). The steam generators would cool the primary by sending steam to the condenser steam dumps. Instead there was a loud noise which indicates that steam was being vented to the atmosphere via the atmospheric steam dumps. This implies that the main steam stops (isolation valves to the turbines) shut. Potential causes for that would be excessive cooldown (an interlock), loss of the condenser vacuum, or a secondary equipment fault. None of these is normal.

I'm guessing that it was probably an electrical fault. A reactor cooling pump trip and secondary pumps could be powered from the same electrical buses since they are not considered safeguards equipment. The other possibility is that the operators didn't control the cooldown properly, or there was an I&C fault that tripped an interlock for the main steam isolation valves.

Disclaimer: I'm familiar with Westinghouse PWRs, but not the Babcock & Wilcox PWRs. So take what I say with a grain of salt.

Re:And, cue shitstorm..

[ozmanjusri]

Maybe.

I'll reserve judgement on what's actually happened, because this industry has a history of salamitaktic, lying, cover-ups and manipulation of public opinion.

It's possible this innocuous announcement is the start of a series of press-releases, each admitting to progressively worse problems. If that's the case, all the Pollyannas on Slashdot will have vanished by the time the real scope of the event is clear.

Re:And, cue shitstorm..

[Anonymous Coward]

Oh for fucks sake. There are event classifications if shit goes really wrong. Since they didn't even declare an Unusual Event (lowest of four classifications), things are under control. It appears that there may have been complications during the trip, but there is no emergency. And for your information, if there is an emergency the plant has to declare it within 15 minutes and inform state and local authorities within another 15 minutes. The people who make these decisions are licensed by the NRC and can be held personally responsible. They are also legally protected from any type of retaliation for taking action based on safety concerns. They aren't going to cover it up for three reasons: 1) their families live nearby, 2) the legal ramifications are severe, and 3) they could easily get another job at any other plant in the country (~2000 workers of their level of training in an industry that wants 3000 or 4000).

Re:And, cue shitstorm..

[Anonymous Coward]

Um, no. This is how these things are supposed to fail.

Re:And, cue shitstorm..

[Anonymous Coward]

buh-buh-buh..... itz nuke-yew-lur! The whirled will end! an-an-an... rad-ee-ATION! An STUFF!

Re:And, cue shitstorm..

[Anonymous Coward]

Obligatory Kingpin reference:

A huge cloud of shit? Wow! I think i smell it!
Hey everyone, there's a shit cloud coming! Run for your lives!

Re:And, cue shitstorm..

[AHuxley]

From the 1960s and 1970s, ~40 years, but dont worry they many in the US got a rubber stamp extension :)
20-year extensions where granted, so expect to see 80 years, and then 100.
The designed for a duty cycle is now a historical number, a better understanding of earthquakes and flooding is put to one side.
The sub systems are also an interesting risk, you can have a great reactor, lots of diesel ready, good protected diesel generators, extra staff on site after they all get called back in - if the cooling systems for the massive diesel units fail nothing is really ready... the full backup system has to work every time..
With age this all gets more complex. Parts fail, a better understanding of the structures and movement under the plant...
Direct inspection is another area that can be interesting ie fall apart and thinning of metal vs paperwork.
New parts are also showing interesting signs of been in need of more inspections very early in their life - ie who pays to replace a brand new upgrade as it thins at a very rapid rate?
http://www.ocregister.com/news/unit-338565-reactor-plant.html

Re:And, cue shitstorm..

[Anonymous Coward]

But, to be fair, isn't this how these things are suppose to work? Something fails, everything gracefully shuts down?

Which won't stop every envirowhack on slashdot from waving his hankie and screaming "NUKLYUR EVIL!!".

Re:And, cue shitstorm..

[Splab]

Would that be rock salt? Perhaps Thorium?

Re:And, cue shitstorm..

[TheLink]

Nah potassium iodide, 130mg.

Re:And, cue shitstorm..

[thegarbz]

Of course it's not graceful but a shutdown as a result of equipment failure never is. Steam venting isn't graceful, but then neither is a SCRAM.

I work in the process industry and the only time a shutdown is ever graceful is through carefully planned and usually long duration operator actions. Even then some processes they just get it down to a stage where there will be minimal damage and then hit the trip button and hope nothing breaks.

The key thing here is what shutdown the process was a safety system which prevented a hazardous event from occurring, rather than hazardous event occurring and causing the shutdown. Compared to that this event really can be considered quite graceful.

Re:And, cue shitstorm..

[Anonymous Coward]

"Three Mile Island is still shutdown Thursday night. Around 220 Thursday afternoon, people who live near the nuclear power plant heard a loud noise, saw steam and then the plant automatically shut down.

This is the second time that this has happened in the past month."

http://www.whptv.com/news/local/story/UPDATE-3-Thursdays-TMI-shutdown-is-the-second-in/_Z1vYirDt0ybASp0FZhmUw.cspx

"The Nuclear Regulatory Commission said Thursday that it was satisfied with Exelon’s repairs following a reactor shut-down at Three Mile Island on Aug. 22.

The NRC said a small leak in the reactor coolant system was caused by “micro-cracks” in a diaphragm in a pressurized heater bundle within the containment barrier. The cracked diaphragm was made of alloy 600; it was replaced with one made of stainless steel, and the unit was powered back up."

No doubt the saga will continue.

Re:And, cue shitstorm..

[dbIII]

It doesn't sound like a graceful shutdown

A "graceful" emergency shutdown of a large thermal power station unit is actually bloody noisy as the steam goes into the blow down vessel/s.
Also any water that touches the turbines doesn't actually go into the reactor, it goes through heat exchangers where the working fluid of the reactor is on the other side.
Disclaimer: I'm familiar with the turbine side (fairly universal amoong all thermal power stations of the same size) but in my case the boilers were all coal fired. There are many similarities to the point where one of my co-workers was a Russian turbine engineer with a lot of nuke experience (and some scary stories).

Re:And, cue shitstorm..

[Chrisq]

Um, no. This is how these things are supposed to fail.

I don't know why this is modded down - its absolutely correct. Nuclear reactors are designed to be "fail safe". If a pump breaks, the system shuts down. There are probably backup pumps in case the shutdown fails too, etc.

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[Anonymous Coward]

This is a very accurate reply with one exception. Generally, the condenser can't support the steam output of the steam generators (they're normally rated around 10-25% of full load). Most plants in the US will steam dump to atmosphere because it's easier and doesn't put unnecessary strain on the equipment.

Plus, dumping to atmosphere has the added benefit is that the whole plant staff knows immediately that they are staying late.

Source: I am an I&C engineer that has worked on many US and European units.

Re:And, cue shitstorm..

[bcmm]

To be fair to the shitstorm, there are historical reasons to be a bit worried when Exelon describe something as a planned release of steam with minimal release of radioactive material. Lets hold out for the NRC report.

Re:And, cue shitstorm..

[Anonymous Coward]

Emergency steam vent to atmosphere is not graceful. Such venting is last resort before rupture. In any steam system other things should have happened before such venting but did not.

Re:And, cue shitstorm..

[tehcyder]

But, to be fair, isn't this how these things are suppose to work? Something fails, everything gracefully shuts down?

Which won't stop every envirowhack on slashdot from waving his hankie and screaming "NUKLYUR EVIL!!".

It's not nuclear power that is evil, it's the fuckwads who end up working there and/or in charge of it. My father used to work in nuclear power stations, and he said once that the opening credits of The Simpsons are closer to reality than most people would like to think.

I'm sorry, but with the nuclear power industry, it's always jam tomorrow. It needs to be tightly controlled by people with no vested financial interest in it, but of course that is too fucking socialist for everyone nowadays.

Re:And, cue shitstorm..

[waferbuster]

Man, and just yesterday I had mod points. Too funny.

Re:And, cue shitstorm..

[zmooc]

As far as I'm aware (and that's not that far, but far enough to reply to this) this kind of pressurized water reactor cannot really shutdown very gracefully. Once such a reactor gets going at normal power levels for some time, it can not shutdown very quickly. The best it can do, is to stop most of the fission reaction (in this case probably a so called Emergency SCRAM). Afterward the SCRAM, the fuel rods will still be Pretty Hot and initially they will still produce about 7% of their normal power due to fission product decay. After a day that's down to about 0.4%, which in this case would still be something like 4 megawatts or so. More than enough to keep things in a closed, well-isolated reactor Really Hot for months to come.

So, in fact, the shutdown-sequence is not graceful at all; it is an extended process that requires active cooling (and therefore working power) and supervision and will result in disaster if it is interrupted for some amount of time.

Re:And, cue shitstorm..

[osmifra]

IF something actually goes bad in Nuclear energy its very hard to cover up something that anyone can measure with a freaking tool!!!! Stop spreading FUD, there's no high levels of radiation and that can easily be measured by anyone. Wanna see cover ups in energy? Go look for carbon mines and fuel refineries and then tell me something. With far more accidents deaths and nature crimes per year each than all nuclear accidents combined.

Re:And, cue shitstorm..

[Anonymous Coward]

Do you dispute any of the facts OP has posted?

Re:And, cue shitstorm..

[Hobart]

I'm guessing that it was probably an electrical fault. A reactor cooling pump trip and secondary pumps could be powered from the same electrical buses since they are not considered safeguards equipment

Dude, you always won at SCRAM didn't you?

Re:And, cue shitstorm..

[drinkypoo]

Nuclear reactors are designed to be "fail safe".

Reactors which require running pumps to not fail are not designed to be fail safe.

Quick quiz, what percentage of the US's reactors fall into this category?

Re:And, cue shitstorm..

[coastwalker]

Pressurized Water Reactors (PWR) are designed to fail safe using active intervention mechanisms and totally don't fail safe if the active mechanism screws up as it did in Fukushima. Personally I would dig up the long dead generals of the nuclear weapon testing era and Kill Them all again for the crime against humanity that they committed. What crime you ask? The crime of denying the world cheap and safe nuclear power.

All of the modern worlds reactors are fundamentally unsafe PWR reactors which were designed and created because the only technology available came from the manufacture of plutonium. Now the only technology available is plutonium generating fundamentally unsafe PWR reactors with so many billions invested in it that we could never build anything else. Its also the reason that Iran can build a nuclear weapon, because all nuclear technology is basically designed to make plutonium for weapons.

The consequence is going to be that we stop using nuclear power altogether just as soon as people realize just what a shit technology is actually being used. Never mind global warming, at least thats only going to kill our grand kids, PWR reactors could easily kill millions of people right now.

Germany, Japan, Sweden have all committed to get rid of nuclear power because they have woken up to the fact that the technology we have now is a total fuckup. Only the Chinese and Indians are likely to carry on with it because they are working on alternative fuel cycle reactors which really are fail safe.

We will have to wait and see if the super rich in America whip the population into line and carry on with PWR power stations or if the sheep wake up and get the whole lot banned. PWR reactors are not fail safe and every hundred years or so one is going to go critical and flood vast areas with radioactive waste. Good luck with that long term.

Re:And, cue shitstorm..

[khallow]

And here we see a member of the "NUKLYUR EVIL!!" crowd in action. Unconfirmable anecdote combined with unrealistic solutions. Bonus points for whining that someone thinks solution will be too "socialist".


Here's my take. As to "jam tomorrow", it's worth remembering that nuclear plants normally maintain their primary promise, delivering power cheaply.

It needs to be tightly controlled by people with no vested financial interest in it

It is, via NRC.

Re:And, cue shitstorm..

[Anonymous Coward]

NRC, National Rubberstamp Commitee.

Re:And, cue shitstorm..

[PopeRatzo]

Oh for fucks sake. There are event classifications if shit goes really wrong. Since they didn't even declare an Unusual Event (lowest of four classifications), things are under control. It appears that there may have been complications during the trip, but there is no emergency.

And we've got every reason to trust Exelon.

"Clean, safe, and too cheap to meter".

Re:And, cue shitstorm..

[Muad'Dave]

Your potassium iodide is radioactive! It emits anti-matter and neutrinos and gamma rays and 'lectrons! Run Away! <sarcasm/>

In case you think I'm kidding, look it up. That 130mg pill undergoes a little more than 1.2 decays/sec.

Re:And, cue shitstorm..

[jellomizer]

Yes, if this was a coal or natural gas plant such an issue wouldn't even make the news. But it is a Scary Nuclear Power plant then it must mean there is a HUGE Poroblem even though the fail safes all worked correctly. Because Nuclear is Scary.

I am not saying Nuclear is Clean, Safe to Cheap to Meter. But really it is one of our better power sources, and we should be sure that we support nuclear and support proper regulation on this energy source as it has a lot of long term dangerous elements to it.

Stop falling to the propaganda of both parties who say either we should go Nuclear and at the same time think the industry will self regulate. Or avoid nuclear all together because you can't trust industries to self regulate.

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[rmstar]

Here's my take. As to "jam tomorrow", it's worth remembering that nuclear plants normally maintain their primary promise, delivering power cheaply.

That has been refuted so many times. Basically, when you add the costs of decomissioning and waste storage, they become pretty expensive. For the tax payer, of course. Plus, if there is an accident, the costs are pretty extreme. Of course, all of that is just an externality to the greedy, corrupt, and incompetent nuclear industry.

It needs to be tightly controlled by people with no vested financial interest in it

It is, via NRC.

That just isn't tight enough, even if it would work as intended. At the moment it is completely inadequate due to something called regulatory capture.

Nuclear reactors, like armies, should not be in private hands.

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[Anonymous Coward]

Make no mistake about it the NRC is in bed with the industry. It makes sense though. We need energy. We want it cheap, and we want it when we flip the switch. We also want to feel like we're safe, and nothing bad is ever going to happen. The industry knows that, and the government knows that. The government is more than happy to take our money to give us the warm fuzzies without actually providing something they are unable to provide (see TSA, social security, border patrol, etc). They're more than happy to take the credit when things happen to go well, and when something bad happens there's plenty of blame to be spread around. As long as nothing catastrophic happens the NRC is more than happy to not rock the boat.

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[Anonymous Coward]

That was my thought as well. Usually you don't vent steam from a normally closed system in a graceful shutdown. Normally you do that because to do otherwise could result in an explosion and full meltdown.

Re:And, cue shitstorm..

[nojayuk]

"Basically, when you add the costs of decomissioning and waste storage, they become pretty expensive. For the tax payer, of course."

Actually no. US and most other Western power reactor operators pay into funds for decommissioning their reactors and also for waste disposal on a kWhr basis. The US rate for waste disposal is 0.25 cents/kWhr which goes to the US government as it is in charge of all high-level nuclear waste since it is seen as a security risk. The current fund total is about 36 billion dollars IIRC. It's the taxpayer that has to deal with coal-slurry lagoons, mercury and other nasties in the exhaust stack, the buildup of CO2 in the atmosphere etc. Legislative attempts to cut down such releases under the EPA and such are a "war on coal" according to, surprise suprise, the coal-mining and coal-burning industry.

As for nuclear power costs in the US, fuel costs are about 0.5 cents/kWhr and operations (running the plant, refurbishing the generators, landscaping the area etc.) are about a cent/kWhr. The killer cost is construction which is all up-front and expensive. It means that once a nuclear power station is up and running it starts paying off the 30 or 40 year financial instrument it took to build it and the owners really want to keep it running 24/7/365 to pay the capital and interest accruing.

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[AmiMoJo]

Actually there is another rather important issue that has not been mentioned yet: reliability. TFA claims that the reactor which was forced to shut down was supplying 825MW. That means there had to be a spare 825MW capacity available instantly in the system to avoid a temporary black-out. Not just "we can spool this up in half an hour", but 825MW of on-line generation capacity being mostly wasted just to cover this eventuality.

As the system transitions away from centralized large scale generators to more distributed small scale electricity sources it becomes more efficient and more reliable.

Re:And, cue shitstorm..

[AmiMoJo]

I am not saying Nuclear is Clean, Safe to Cheap to Meter. But really it is one of our better power sources, and we should be sure that we support nuclear and support proper regulation on this energy source as it has a lot of long term dangerous elements to it.

This incident just illustrates the point that nuclear isn't well regulated enough and probably never will be. TMI is an old design that should be been shut down a long time ago and replaced. That would cost a lot of money though so instead the license just keeps getting extended.

At this point someone will usually suggest thorium as the solution to all our problems, but the economic reality of building such a plant makes it impossible. No-one is willing to pay the cost, not investors, companies, the government, the taxpayer or the consumer.

Re:And, cue shitstorm..

[AmiMoJo]

That's not what fail safe means. In this case when the pump failed a number of things had to happen for the failure to be safe. The reactor probably SCRAMed and emergency cooling kicked in. Without those systems and careful management by staff the reactor could fail like Fukushima did.

If it were fail safe the failure of the pump itself would have made the whole thing completely shut down into a safe and inactive state. I used to work in fire suppression for buildings and when we had a fire door that was "fail safe" that meant it was held locked shut by an electro magnet, so if the power failed for some reason it would automatically unlock and allow people to escape. In fact even if the control system stopped communicating it would open. No action by anyone or anything else required.

Re:And, cue shitstorm..

[iamgnat]

ozmanjursi didn't post any fact and yes I dispute their claims. The nuclear industry in the US has proven to be safe, they promptly report even minor incidents, and to the best of my knowledge have never lied about conditions at their plants or the scope of an event. What happened in other countries has no bearing on what happens in the US until there is evidence to the contrary.

As osmifra points out, the fossil fuel power supply industry (mining up through the power plants themselves) do have a long history of raping the natural resources, not providing safe working conditions for their workers (miners), being horrible polluters, and having massive lobbying arms to make sure that any regulations that do get passed to curb these things have no teeth to actually stop them. Nuclear power, on the other hand, is very tightly regulated (see lobbying power of the fossil power as a big part of that) and does none of those things.

Re:And, cue shitstorm..

[Anonymous Coward]

I don't agree with this. Very few plants have condensors that can handle a 100% steam dump.

When you dump the steam load, it is loud and gets everybody's attention, but it is normal.
There was a video on youtube a couple of years ago that showed a steam dump at one of the Duke plants.

Re:And, cue shitstorm..

[MachineShedFred]

Yes. It's called a "fail safe."

In the event of a failure (coolant pump stops working), the system remains safe (automatic shutdown).

Working as designed.

Re:And, cue shitstorm..

[Medievalist]

Nuclear power, on the other hand, is very tightly regulated

By the nuclear power industry. It's called "regulatory capture".

Re:And, cue shitstorm..

[bobbied]

As the system transitions away from centralized large scale generators to more distributed small scale electricity sources it becomes more efficient and more reliable.

True in some ways... Except when you are using standard "green" energy sources for power generation. Bad things happen when the wind stops blowing or a cloud drifts by. Even on the best day, you can only count on about 20% availability of capacity from wind or solar, which means you have 80% reserve capacity available from fossil fuels not being used. One green exception to this is hydro-electric, which can usually be throttled up in a very short time and doesn't usually suffer unplanned outages.

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[thegarbz]

I don't think the plant had the spare capacity, but rather the grid did. 825MW is nothing compared to the difference between peak and base load for a large city. I'm not sure if America publishes openly the daily electricity trading stats like in my country but in my state which has a population less than 1/3rd that of Pennsylvania the peak to base swing changes by more than 5GW daily.

If you run your powerplants like we do with very little peak smoothing capacity then yes 825MW suddenly missing from the grid may not even be enough to make your lights dim. But I'm not sure on the timing of the incident. If it happened in peak times I would question it as well.

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[Muad'Dave]

Quick quiz, what percentage of the US's reactors fall into this category?

Survey says...Quite nearly 100%. The only exceptions are test reactors, IIRC. Sadly, the so-called environmentalists have effectively prevented implementation of real Gen IV reactors that actually ARE failsafe.

Re:And, cue shitstorm..

[Anonymous Coward]

This would be news if we read that... A coolant pumps failed and the reactor safey system did not respond as it should have.

Let's put this in perspective.
As a reactor operator, I have personally caused an automatic rapid reactor shutdown (called a reactor SCRAM in US Navy nucelar power terms) myself from an invalid coolant pump combination [note 1].
I'm not sure what TMI uses for setpoints but in general...
A reactor safety system compares running coolant pumps to measured power output. For a given pump combination, you can run at a certain power level. When the Power:Flow ratio exceeds a setpoint, the protection system will immediately take action. If a pump fails and you are above your power limit for the new lower setpoint... bam, protection system kicks in. No harm, no foul. That's what it does and it did it.

Getting off topic but my story anyway..
Note 1
In my case, the pump did not fail, I failed. I am not the only one that has done this and it happens a lot. We were running some test drills that put the plant into an abnormal but perfectly acceptable coolant pump combination (one pump in each loop running in fast). This was after we had lost a turbine generator. Everything was fine until we started losing the other turbine generator which was not planned. In the protection system we had, when you change a coolant pumps speed, you go through a condition for a fraction of a second where the pump is considered "off" by the protection system and it actually is because it's wired to prevent both fast and slow speed windings from being powered at the same time. It compared power:flow and it scrammed. I shifted pumps too fast based on the conditions I had seen and what I expected to happen next. In my mind I assumed we were about to have a complete loss of flow if I did nothing as that other electrical turbine went away. Frequency was starting to flucuate and I took action. At the same time, they were restoring vaccuum to that turbine and it never actually went away. Maybe my unloading gave it enouhg time to reocver, maybe not. The whole situation from doing good and stable to the shit hitting the fan and a total reactor shutdown was about 10 seconds. Given the overall situation of events, nothing happened to me even though I technically caused the protective action because I may have potentially saved a worse condition of no flow which would have taken a much longer time to recover from if I did nothing.

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[Baloroth]

Nuclear reactors are designed to be "fail safe".

Reactors which require running pumps to not fail are not designed to be fail safe.

Yes, they are. They are not designed to be fail safe if everything fails, but they are designed to be fail-safe if there is one or two failures, that's what the back-up pumps are for. Just because it is possible for a system to fail in a 1-in-a-trillion case doesn't mean the system isn't "fail-safe", if you used that definition it would apply to absolutely nothing (literally nothing).

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[nitehawk214]

Pressurized Water Reactors (PWR) are designed to fail safe using active intervention mechanisms and totally don't fail safe if the active mechanism screws up as it did in Fukushima.

Except that Fukushima was a Boiling Water Reactor. BWRs are a unsafe poor design. PWRs are designed with failsafe systems. But don't let that get in the way of your anti-nuclear rant, you are on a roll.

Re:And, cue shitstorm..

[jemenake]

But, to be fair, isn't this how these things are suppose to work? Something fails, everything gracefully shuts down?

Yes. In fact, back in 1979, it became evident that there was one safety feature that they forgot to put into the design of the plant: one which would, at the first sign of a problem, release poison gas into the control room. You see, the plant would have gracefully shut itself down had the operators not overridden those safety features, forcing the reactor to keep going and causing the TMI event. Now, in their defense, the dudes in the control room were legitimately worried that the automatic shutdown would have taken the reactor off-line for weeks, if not months... which would have caused... y'know... loss of revenue. Can't have that.

What's eerie is how similar this latest development is to the 1979 event. Some cooling pumps were shut down, then there was a release of steam, then the announcement that the steam didn't have any radiation... then the announcement that, well, there wasn't that much radiation in the steam... then the announcement that, even though there was no risk to the public, they wanted all the kids and pregnant women to GTFO...

Lastly, as a point of clarification, from what I've read, Three-Mile Island wasn't a meltdown. The fuel-rods shattered from the heat, but they didn't get so hot that they melted. Now, Chernobyl... if you want to see a solidified "lava flow" of molten uranium draped over concrete beams... that's a man's meltdown, right there. The Soviets didn't do anything half-assed.

Re:And, cue shitstorm..

[Anonymous Coward]

I would have thought a single reactor pump trip would not be a full scram just a runback to 75% power.

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[Creepy]

True enough, and the AEC (Atomic Energy Commission) was dissolved for the same problem the NRC is in today - they are in bed with the industry. Even in the mid-1980s, the industry considered the NRC a rubber stamp of approval for whatever they wanted to do, and it was proven before congress... and they did nothing about it. Gotta love regulatory commissions that exist strictly to deter other forms of reactors being implemented.

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[Creepy]

Thorium is an alpha emitting metal, not a salt. Perhaps you're thinking of the Fluoride salt used in liquid metal reactors (which can burn Thorium or Uranium).... or Potassium Iodide, as TheLink suggested (used to treat radiation exposure), lol.

Re:And, cue shitstorm..

[Creepy]

What was probably meant is Light Water Reactor (LWR), which covers both PWRs and BWRs, and there is some semi-informed indications in there, as well - India is actually working on a thorium powered LWR, which is just as unsafe as typical LWRs. China is working on a LFTR, which can't melt down and has other inherent advantages like burning almost all of its fuel with little and short lived waste. The US continues to dump massive amounts of money (almost 1 trillion dollars last I checked) into Fast Breeder Reactors, which also are inherently unsafe, but maximize neutron efficiency (generate more power per fission). The sad thing is, the estimated cost to build a prototype LFTR is... 5 million dollars - less than a coal plant.

Re:And, cue shitstorm..

[ultranova]

Clearly, we need more backup pumps for shitstorms.

We'd need more nuclear plants to power the pumps, which would result in more shitstorms, requiring more pumps and so on. It's a vicious cycle.

Re:And, cue shitstorm..

[mcgrew]

True in some ways... Except when you are using standard "green" energy sources for power generation. Bad things happen when the wind stops blowing or a cloud drifts by. Even on the best day, you can only count on about 20% availability of capacity from wind or solar, which means you have 80% reserve capacity available from fossil fuels not being used.

A sunny day is usually not a windy day, a rainy day is. The hydroelectric works 24/7/365, as does tidal and geothermal. Generate the rest with nukes.

Re:And, cue shitstorm..

[HornWumpus]

It's called spinning reserve. Mostly turbines running at idle and hydro units that are river flow limited on generation anyhow. The hydro units in particular are not wasting any energy waiting to be called on. That said they are limited on ramp rate as putting a 'wall of water' down most rivers is not allowed (for good reasons; dangerous, erosive. Also strands fish when it stops). The exception there is when one reservoir cascades directly into another, those can more or less ramp as fast as the equipment will allow (which is pretty fast).

Also note: the system just lets the voltage drop (browns out) while the 'ready reserve' units spin up. 120 VAC is purely nominal. Talk to someone that designs 120VAC power supplies. They should function down to about 95V IIRC. This is by design.

Also also note: most transmission areas are both importing and exporting at any given time. They can always just cut their exports and shift a part of the issue to their neighbors. Increasing imports isn't likely to happen in the middle of the day. The lines were likely running at max capacity to begin with.

Re:And, cue shitstorm..

[Anonymous Coward]

The NRC Event Report:

Power Reactor Event Number: 48325
Facility: THREE MILE ISLAND
Region: 1 State: PA
Unit: [1] [ ] [ ]
RX Type: [1] B&W-L-LP,[2] B&W-L-LP
NRC Notified By: DAVID LEWIS
HQ OPS Officer: JOHN KNOKE Notification Date: 09/20/2012
Notification Time: 16:15 [ET]
Event Date: 09/20/2012
Event Time: 14:16 [EDT]
Last Update Date: 09/20/2012
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
        Person (Organization):
CHRISTOPHER CAHILL (R1DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 A/R Y 100 Power Operation 0 Hot Shutdown

Event Text
AUTOMATIC REACTOR TRIP DUE TO REACTOR PROTECTION SYSTEM ACTUATION

"On September 20th at 1416 EDT, Three Mile Island automatically tripped due to a flux to flow imbalance as a result of a trip of the 'C' reactor coolant pump. The cause of the trip of the 'C' reactor coolant pump is still under investigation.

"The electrical grid is stable and unit 1 is being supplied by offsite power. All control rods have fully inserted. Decay heat is being removed by main feedwater flow to both steam generators that are exhausting via the normal main condenser cooling loop under manual control. Preliminary evaluation indicates that all plant systems functioned normally following the reactor trip, except for automatic operation of turbine bypass valve control due to failure of the automatic control function to control precisely at setpoint. Three Mile Island remains stable in hot shutdown mode while conducting the post trip review. No radioactive releases were experienced as a result of this event.

"This event is reportable under 10 CFR 50.72(b)(2)(iv)(B), Reactor Protection System (RPS) actuation, and under 10 CFR 50.72 (b)(2)(xi) due to an information release to local officials. Both are four hour reports.

"The licensee notified the NRC Resident Inspector."

The licensee has notified the state and local governments, and will be making a media release.

As far as your note on condenser steam dumps, it is true they aren't rated at full load. For a reactor trip that isn't a problem since only decay heat (6% at the time of trip and decreasing afterwards) is need to be removed. In a trip the condenser steam dumps would reduce the reactor coolant system temperature to the shutdown band. This report really doesn't explain the loud noise. Why there would be a venting of steam for a turbine bypass valve failure is unknown. If they wanted to isolate it they could have shut the main steam stops. But they claim they are cooling via condenser steam dumps. As far as NRC event reports, this one is unimpressive and doesn't explain what it needed to do. I expect there will be a followup report clarifying to the NRC what operator actions were taken and how they vented steam.

Plus, dumping to atmosphere has the added benefit is that the whole plant staff knows immediately that they are staying late.

Been there.

Re:And, cue shitstorm..

[Anonymous Coward]

What fuckwit moderated this pile of platitudes up?

Are you all a bunch of sycophatic drooling fools?

Read the fucking comment! It's just random Pollyanna shit that doesn't make the slightest bit of sense!!

Slashdot truly is fucked. You losers deserve to wither and die.

Re:And, cue shitstorm..

[HornWumpus]

Gravity feed backups make them fail safe. The kind of backup that was _not_ retrofitted to Fukushima BTW.

You can calculate the residual decay heat in a core that scrams while running at 100% and design a gravity fed reservoir with enough water. Convection is enough to keep the primary loop running on decay heat.

Re:And, cue shitstorm..

[firex726]

Yea, wasn't there that reactor facility a couple years back that was leaking Tritium from a pipe that was not on any registered blueprint and they ended up getting a slap on the wrist fine?

Re:And, cue shitstorm..

[Compaqt]

I find it funny that the government thinks that changing the names of agencies actually results in anything better. (INS to ICE, Dept. of Homeland Security, etc.)

Also the fad of calling stuff nuclear instead of atomic.

Re:And, cue shitstorm..

[firex726]

It's due to all those NIMBY people.

New designs are really safe, much more then the existing ones, but we can't build them since no one wants one in their state/city.
We need the power, but we can't build new ones so we're forced to keep running the ones we have passed their duty cycle.

Re:And, cue shitstorm..

[Urza9814]

People also have a tendency to MASSIVELY exaggerate any sort of problem involving the word 'nuclear'. I've seen comparisons of news coverage of the 1979 TMI incident -- the further away you were from the site, the more apocalyptic the coverage became. Locally it was pretty honest -- 'minor incident, small release of radiation, nothing to see here'...on the other hand, I know some people who went overseas shortly after (to France FWIW) and when they mentioned to people they were from Pennsylvania, those they talked to refused to believe them -- the news over there was that the entire state of Pennsylvania was one big smoking crater! If you look at how the national US media covered the incident it's somewhere in the middle.

Re:And, cue shitstorm..

[Anonymous Coward]

Oh yeah I forgot all "Unusual Events" and emergency's are always reported immediately by the workers at these plants, because "The people who make these decisions are licensed by the NRC and can be held personally responsible"..... Your cool-aid cup is a bit on the empty side.

I forgot our government is always upfront and honest when reporting issues concerning our safety. "There is no danger to the public, but the release of steam in the process created "a loud noise heard by nearby residents," the company said.' If radiation was released into the environment, it is so low that it thus far has not been detected". Classic!

Re:And, cue shitstorm..

[tibit]

The 1979 TMI was nothing much. I never understood why people talk of it like it was Fukushima or something. Yes, Fukushima was bad, Chernobyl was bad, criticality events in the labs are bad. Every other nuclear accident out there is really nothing to lose any sleep over.

Re:And, cue shitstorm..

[tibit]

This is perhaps the most informative post of the day. If someone thinks things are bad with reporting in the nuclear industry in the U.S., feel free to look up similarly detailed reports for fossil mining of any sort. Hint: it doesn't exist, or prove me wrong.

Re:And, cue shitstorm..

[tibit]

Exactly. Antineutrinos FTW :)

Re:And, cue shitstorm..

[Anonymous Coward]

He never does. Ozmanjuri is a pudwhacking prick. Nothing more.

Re:And, cue shitstorm..

[Fierlo]

and to the best of my knowledge have never lied about conditions at their plants or the scope of an event

That's not really true. Davis Besse was not very forthcoming, to put it lightly, about the conditions of the pressure vessel. A quick google should provide you with a reasonably good story about this one. I believe some people were actually prosecuted for it.

Re:And, cue shitstorm..

[tibit]

Voltage dropping was helpful when a lot of the load was resistive (incandescent lightbulbs, linear regulators in most low-voltage equipment, etc.). As the voltage dropped, the power demand dropped as well. These days, the switching power supplies are negative resistances and as the voltage drops the power demand doesn't drop. In fact, due to typically lower efficiencies with lower input voltage, the power demand goes up as the input voltage drops! From what I imagine, one fine day the U.S. grid won't be able to cope gracefully with such loads in presence of lowered generating capacity. That day isn't very far away. Every data center and every plant where servo drives or induction motors are used is already such a negative resistance load. Due to switch to fluorescent lightbulbs and brushless drives in appliances, never mind all the IT/entertainment tech in homes, homes are becoming such a load as well. I have checked the effective differential impedance of my home with AC working and a bunch of other things turned on, and it is negative -- I don't recall the exact complex value. There were about 3 extra Watts wasted due to inefficiencies per every Volt of voltage drop over a constant-power ideal, going from 135V to 105V (I used a buck/boost transformer to vary the voltage going to the panel). That was an average over 1 minute with A/C going full blast, the computers on, cellphones charging, TV on, freezer and fridge compressors going, and both washer and dryer operating. The dryer has a tight digital temperature controller and will present a roughly fixed load in spite of lower input voltage. Of course mechanical thermostats acted the same way, but with an order of magnitude slower response.

Re:And, cue shitstorm..

[tibit]

Never mind that you don't want any water droplets reaching the turbines at all. They'd erode the blades in no time. Gaseous water is key ;)

Re:And, cue shitstorm..

[neonfrog]

"The nuclear industry... have never lied about conditions at their plants or the scope of an event."

Google "Vermont Yankee Lied Under Oath" for your own education. It is very hard to find an unbiased source, but this is the best I can find:

"The underground pipes were of the sort that plant officials had earlier told lawmakers and the Public Service Board — the later under oath — didn’t exist."

I think modern nuclear power is important, and I'm usually a nuclear proponent, but Entergy is hard to love.

Re:And, cue shitstorm..

[tibit]

That's idiotic. Not all explosions in a thermal power plant (a nuke powerplant is thermal, duh) will result in a meltdown of the reactor core. If a secondary loop would, say, crack and explode, you isolate it and keep going with what's left. It's plenty to cope with decay heat that's always 10% less than full rated power, even immediately after the rods hit the bottom stops.

Re:And, cue shitstorm..

[tibit]

This thinking shows that you have absolutely no clue about how real functional process safety engineering is done. Fail safe means that when you have a certain number of failures (for a nuke plant probably two), things are still safe. So you can have, say, a concurrent turbine trip and a pump failure in a primary circuit, and things should end up in a safe state. Fail safe doesn't imply passive safety, it's only your fantasy and a view that's not shared by those who actually deal with functional safety. Passive safety may be a means of achieving functional safety of a process system, but it's by no means the ultimate cure-it-all in spite of what clueless fools spout left right and center. Passive safety isn't a fix for bad functional safety engineering. Fukushima was was an example of the latter. You can't tell a-priori that some passive safety in the system would not have prevented other problems. For all I know passively safe reactor might have prompted "savings" in other aspects of the design, say putting it lower and closer to the ocean, for example.

Re:And, cue shitstorm..

[tibit]

In Fukushima it wasn't an active mechanism that screwed up. Everything acted exactly, to the letter as designed. The plant wasn't designed to cope with a certain failure mode. The safety engineering of the site wasn't done right. That's all.

Re:And, cue shitstorm..

[turbidostato]

"I find it funny that the government thinks that changing the names of agencies actually results in anything better"

I find it funny that you think government change the name if agencies aiming to change anything.

Re:And, cue shitstorm..

[tibit]

It is entirely a figment of your imagination that fail safe implies passive safety where things don't "have to happen" for the failure to be safe. It's fucking meant to SCRAM, to have emergency cooling, and to be carefully managed. It's by design, and it works. I don't understand what is this magical bond people have with passive safety. You can design for passive safety, but it's not going to be any better than active safety because, again, you engineer it for a certain rate of catastrophic failures no matter what technical solutions you employ. The rate of catastrophic failures is given by regulatory and internal project requirements and you design for that, end of story.

A door that you mention was only fail safe when it came to a certain failure mode of the electromagnet or its control circuits (loss of power, severing of wires, short circuit in the wires). Had the control circuit stay inadvertently energized in case of a fire, it wouldn't fail safe. Had there been a stuck hinge or a chair in the way, it wouldn't fail safe. You show the typical, arrogant know-it-all approach to safety, with essentially cargo culting certain artifacts without demonstrably having a clue about the engineering process involved in actually designing functional safety into the systems.

Hint: passive safety is a tool available to those who engineer a safe system. In itself it doesn't lead to a system that's inherently any more or less safe. You do a failure mode analysis and do the probabilistic calculations that tell you how robust things need to be in order to keep catastrophic failure rates low enough. If you screw that up (like in Fukushima), passive safety isn't going to save you, because your assumptions were wrong and there will be other aspects of the system which will be likely equally screwed up -- say the spent fuel rod storage.

Re:And, cue shitstorm..

[tibit]

That's only by your own imagination. Yes, it'd be "last resort before rupture" iff it was a dump done by pressure relief valve that protects a vessel or piping from mechanical over-stress. Basically, by your own admittance, you're limited to thinking about a household hot water tank. That wasn't the system in question now, was it, AC?

Here, it was a vent used to remove heat from the system. Nothing would blow up just because they woudn't dump that steam. Things would overheat and get perhaps damaged or would require costly reinspection and requalification, but there wouldn't be any explosions, not right away anyway. Protip: if you've got a source of cold water to inject into a loop to be cooled down, you eventually have to do something with the steam that accumulates in such a loop. If there's no heat exchanger capacity to recondense the steam, you vent it. That's all there's to it. Sigh.

Re:And, cue shitstorm..

[tibit]

TMI is an old design that should be been shut down a long time ago and replaced. That would cost a lot of money though so instead the license just keeps getting extended.

What the fuck? You can't demand that it be cheap n' easy and then change rules of the game to make it not so by demanding they are shut down on your schedule. The plants were designed to operate as long as everything holds up, there were certain aspects of their designs that were at the time unknowns, mostly related to how various materials will hold up over time in given environment simply because there wasn't 100+ years worth of engineering experience with nuclear power plants like there was with pressurized steam aspect of things. There's nothing bad about this design simply because it's old. In fact, if anything, its shortcomings, if any, are much better understood after it has been long time in operation, so certain unknown probabilistic factors that are used in doing failure mode and risk analysis have tighter bands on them, leading to streamlined inspection and refurbishment.

The plants will operate as long as it's economical to do so. There's no reason whatsoever to do otherwise.

Re:And, cue shitstorm..

[bobbied]

I don't think tidal would be useful at all times, but that aside... We've pretty much maxed out the hydroelectric capacity we have here in the US (unless you count the dams they are taking down) and geothermal capacity is *extremely* limited. Other "renewable" sources are not reliable enough to depend on for peak capacity needs.

Nuclear power is not a good source of peak capacity because they are hard (and/or expensive) to throttle up and down due to fuel cycle considerations. Fossil fueled plants will be with us for a *long* time, because they are easy to throttle up and down. Not to say we could not use a LOT more Nuclear plants but we will need to somehow shift loads from peak times to off peak times to make the best use of their fuel.

One scheme I've seen that looked promising was to pump water up a hill when electric rates where cheap (i.e. at night) then selling the hydroelectric power you could generate from the water and sell it at peak rates during the day. Maybe we could get the background electric rate cheap enough for that to work by building a few Nukes...

Re:And, cue shitstorm..

[Anonymous Coward]

PWR reactors could easily kill millions of people right now.

Really? How?

Re:And, cue shitstorm..

[ultranova]

This incident just illustrates the point that nuclear isn't well regulated enough and probably never will be.

Regulated well enough for what?

Current population densities and quality of life are not possible without large-scale power production. Both agriculture and industry require it, as does infrastructure such as transportation, running water, sewage treatment etc. So unless you're willing to condemn most people to death and the rest to a miserable life at barely subsistence level, you need to produce energy, and lots of it. But how? Solar and wind can't do so, and water is pretty much tapped out. Fossil fuels can, but causes huge enviromental damage and besides the fuel is running out. That leaves nuclear.

So, regulated well enough for what? That it beats starving to death in the dark? Sure it is. That it's better than a power source that can produce huge amounts of power yet is totally safe (which is impossible - energy is inherently dangerous)? Well, reality can never beat fantasy, but it's highly irresponsible to make decisions that affect billions of people and the future of the entire species based on daydreams, no matter how pleasant or nightmarish they might be. Something else? Please elaborate.

Re:And, cue shitstorm..

[danbert8]

There's no good data on "nature crimes" but as far as accidents and deaths go... http://www.bls.gov/news.release/archives/osh_10202011.htm

The mining and petroleum industry in 2010 had an overall OSHA recordable rate of 2.3 (oil alone was a mere 1.2), which is much lower than the private sector average of 3.5. Utilities in general came out at 3.1.

http://www.bls.gov/iif/oshwc/cfoi/cfch0010.pdf (sorry, fatality data is only in pdf form)

Only 9% of workplace fatalities come from exposure to harmful substances or environments. While the mining fatality rate is high, it is still below agriculture/forestry, and comparable to transportation and warehousing. The occupations with the highest rates of fatalities don't have any related to mining or oil. Electrical line workers is in the top 10, but is true of all energy plants (even wind and solar).

Re:And, cue shitstorm..

[danbert8]

The better question is what type of day results in the highest power demand. Typically hot, sunny, windless days are the peak draw due to air conditioning use. That would imply that solar power is much more beneficial for peaking demand than wind.

Re:And, cue shitstorm..

[Anonymous Coward]

Is there a specific Exelon, or even US based example you can cite, rather than allude to? Otherwise, I'm not saying you raped and murdered a 15 year old girl, but I wonder why you haven't denied it...

Re:And, cue shitstorm..

[HornWumpus]

IEEE FERC UL or whoever is in charge of such things should spec a brownout shutdown voltage (and a range, so they don't all shut off at the same second) for unimportant wall warts. Won't help when all the AC motors are replaced with brush-less though. Motor controllers will almost have to become brownout aware and go into deliberate low power limp modes or shutoff completely.

Ultimately they will have to increase reserves and load following capacity or the current limits will be as graceful as things get. Rolling blackouts etc.

Solar should on average help reduce load change rates. It's coincident with load in most places most of the year. Wind is a simple crap shoot as far as scheduling goes. You almost have to design for it going away just as load picks up.

Re:And, cue shitstorm..

[khallow]

That just isn't tight enough, even if it would work as intended. At the moment it is completely inadequate due to something called regulatory capture [wikipedia.org].

And what's going to keep the "tighter" regulation from suffering from regulatory capture either.

Nuclear reactors, like armies, should not be in private hands.

Or maybe it's evidence that regulation shouldn't be in public hands. After all, they don't have a vested interest in whether they do their jobs or not.

Re:And, cue shitstorm..

[Anthony Mouse]

The 1979 TMI was nothing much. I never understood why people talk of it like it was Fukushima or something.

China Syndrom film release date: March 16, 1979.
Three Mile Island Accident date: March 28, 1979.

Re:And, cue shitstorm..

[plover]

Clearly, we need more backup pumps for shitstorms.

We'd need more nuclear plants to power the pumps, which would result in more shitstorms, requiring more pumps and so on. It's a vicious cycle.

Sounds more like a viscous cycle.

Re:And, cue shitstorm..

[EnglishDude]

Pumped storage is not a new idea. For example in the UK we've got Dinorwig power station which was built in 1974 in anticipation of all the nuclear power stations that was going to be built. As it didn't happen, Dinorwig was re-purposed to be a peaking power station, and to be used in case the National Grid needed a black start.

Three Mile Island is STILL open?!?!?!

[Anonymous Coward]

I for one welcome our new glow-in-the-dark overlords.

Re:Three Mile Island is STILL open?!?!?!

[fredgiblet]

Implying Three Mile Island was even a big deal.

Re:Three Mile Island is STILL open?!?!?!

[sjames]

Yes, TMI-1 is running just fine and has been ever since we figured out what happened to TMI-2 and how to not have it happen again.

Re:Three Mile Island is STILL open?!?!?!

[petermgreen]

Due to a combination of nimbyism and practical considerations it's very common to have multiple reactors at one site.

TMI-2 was where the famous accident happens and was shut down permanently due to massive internal radioactive contamination. Afaict TMI-1 has had minor incidents over the years but nothing that would require a permanent shutdown.

Re:Three Mile Island is STILL open?!?!?!

[quenda]

Why not? You might be surprised to hear that the Chernobyl power station operated until 2000, 16 years after the well known incident.

Fukishima may not do so well. Losing a single reactor, as the US and USSR did, may be seen as bad luck. Losing three of them is an embarassment.

Re:Three Mile Island is STILL open?!?!?!

[Anonymous Coward]

They'll fire up Fukushima 5 and 6 again. Just you watch. Yes, I know the Japanese are supposedly abandoning nukes. I also know they're going into a debt crises, have become net importers and sometime in the next 10 years they will stop indulging idiocy and put the nukes back on line.

Re:Three Mile Island is STILL open?!?!?!

[c0lo]

I also know they're going into a debt crises, ...

Well... it's not like US have a monopoly on QE - Japan is at its eight already.

Re:Three Mile Island is STILL open?!?!?!

[dbIII]

It was a huge deal. A plant with a control system that wouldn't even pass regulations at a fertilizer works showed that you couldn't play fast and loose with nukes just because there were no regs to prevent you doing so, so that meant improvement of some other plants, shutting down some absolute deathtraps of the 50s and 60s, and a move towards better designs.

Re:Three Mile Island is STILL open?!?!?!

[tehcyder]

Implying Three Mile Island was even a big deal.

If this was a fucking software discussion I'd be calling you a paid shill for the nuclear power industry now and getting modded up for it.

But as the slashdot groupthink is that anyone who is not 100% a cheerleader for nuclear power is some tree-hugging commie, we all know what will happen.

Re:Three Mile Island is STILL open?!?!?!

[MachineShedFred]

There's more than one powerhouse at TMI. Only Unit 2 had the partial meltdown, and was ruined beyond repair. Unit 1 has been operating ever since, as it was powered down for refueling during the events of 1979.

Re:Three Mile Island is STILL open?!?!?!

[Anonymous Coward]

Thankfully, hubris blinds nuclear power supporters into forgetting about human error.

Also, profits!

Re:Three Mile Island is STILL open?!?!?!

[Tenebrousedge]

Actually the tree-hugging commies I know also support nuclear power too. Would you rather have your radioactive waste in the atmosphere (coal) or in a barrel? Do you harbor some fantasies of solar and wind being able to provide baseline power? Do you think that we'll develop batteries with the required power density, that somehow won't be dangerously explosive on their own?

So go ahead Mr. Critic, what's your solution? Or are your insights limited to pandering and denunciation?

Re:Three Mile Island is STILL open?!?!?!

[digitalsolo]

You know, really, the commie's love nuclear power. You'd think the tree huggers would too.

soggy hand luke

[Anonymous Coward]

why not power an island with the furious masturbation of basement dwellers?

Re:soggy hand luke

[GameboyRMH]

On a comedy site a commenter recommended combining the fleshlight and a linear magnetic generator (as used in shake-charge flashlights). Energy problems: Solved XD

Some one in 7G messed up

[Joe_Dragon]

Some one in 7G messed up

Re:Some one in 7G messed up

[nihilistcanada]

If only Frank Grimes had lived, none of this would have ever happened.

Re:Some one in 7G messed up

[Anonymous Coward]

Hmm... Nuclear power mishap? Pennsylvania? Sounds like its time for my comic book featuring an atomic Amish super team. Send in the X-Menonites!

Granted I doubt Three Mile is near any Anabaptist communities, and Menonite is different from Amish. But I'd pay to see that book.

Re:Some one in 7G messed up

[Ginger Unicorn]

That idiot Tibor...

Add it all up

[medcalf]

Embassy attacks. Crap economy. Foreign policy humiliation. Three Mile Island. Am I the only one who didn't like 1979 the first time, and don't want a replay?

Re:Add it all up

[arkane1234]

We did not have a recession starting more than 4 years before 1979... at least we've exceeded our failures in that respect.

Re:Add it all up

[Anonymous Coward]

It takes a Jimmy Carter to get a Ronald Reagan.

Just sayin.

Re:Add it all up

[treymd]

This is not a Carte-Reagan election. Unlike Carter, Obama did nothing prior, during, and likely after his term, and Mitt Romney is a terrible actor.

Re:Add it all up

[Anonymous Coward]

Let's hope we get something as good as The Wall again this time.

Re:Add it all up

[Anonymous Coward]

I was born in '79, what's not to like? ..oh a quick google says: 'everything'.

Sorry mate.

Re:Add it all up

[Splab]

Yes! Always strive to improve!

Re:Add it all up

[tehcyder]

At least the music was better back then. Now get off my lawn.

Re:Add it all up

[tehcyder]

Ronald Reagan was also a terrible actor.

As well as being a terrible politician and a truly evil president.

Re:Add it all up

[Anonymous Coward]

Ronald Reagan was also a terrible actor.

As well as being a terrible politician and a truly evil president.

Ronald Raygun, remember he championed the Start^H Wars program.

Re:Add it all up

[drinkypoo]

How unusual, an AC came to say what I came to say. Happens though.

Right now the manufactured crisis (manufactured by exporting jobs and doing nothing to create more) is the recession/depression. Then it was the oil crisis (manufactured by big oil's SOP.)

Re:Add it all up

[Anonymous Coward]

It's not the boss's fault that his henchmen fucked up? Let me give you a hint. It is always my fault when my subordinates, at any level, fuck up. With great power comes great responsibility. It's one of those military things. The president is the commander in chief, and responsible for the operation of the US military.

Re:Add it all up

[drinkypoo]

Perhaps you should stop overreacting as neither now nor 1979 were really 'bad' by any real sense of the word.

How about the sense of being much, much worse than it could be?

I'll still complain about having a finger cut off even if someone else is losing their nuts.

Re:Add it all up

[arth1]

Lots of good things happened in '79.
- Smallpox was eradicated
- The Sony Walkman was introduced (am I the only one missing those?)
- Sony and Philips presented (prototype) CDs
- Voyager I took pictures of Jupiter
- Pioneer 11 took pictures of Saturn
- Ariane was launched
- Usenet started

But I don't want a repeat, because in 1979, we almost ended life on this planet too, when NORAD erroneously detected a large amount of missiles from USSR heading towards the US. An operator had loaded a test tape into the live system without changing the system status to test.
And almost equally horrible, the top song of the year was "My Sharona" by Knack.

If I could get a re-run of a year, it would have to be 1776. Nothing of importance happened then...

Re:Add it all up

[Anonymous Coward]

Yes, and now if only we had a Ronald Reagan type option I might be hopeful. I like Romney far better than Obozo, but he's no Reagan.

Re:Add it all up

[Sarten-X]

Am I the only one who didn't like 1979 the first time, and don't want a replay?

As far as politics goes, yes.

The 50-year-old politicians in office now were 20 in 1979, and now see their world history through the rose-colored glasses of their youth. Without the understanding of what led to problems before, the politicians and policy-makers blunder onward, in blissful ignorance of upcoming crises. Last time these issues came up, everything seemed so simple (as everything usually does to twenty-somethings) that the prerequisite conditions were ignored. Now those conditions have returned, and the politicians would rather fight over 55,000 immigrants (that's 0.01% of the US population) than worry about what long-term problems are approaching.

As I've often said, everything is far more complex than any politician will admit. Nothing a single President or Congress administration can do can fix the economy, or bring peace to the world, or cure cancer, or eliminate hatred. All we can do is realize that we're a very small part of a very large machine, built by millions of years of entropy screwing things up. We should quit trying to use quick fixes for every problem, and instead focus on not breaking things in the same way over and over again.

That philosophy won't win elections, though.

Re:Add it all up

[ultranova]

Ronald Reagan was also a terrible actor.

You don't have to try very hard when you're trying to convince rich people that it's okay to be selfish dicks. Or, for that matter, convince poor people that they will stop being poor if they just try hard enough, ironically enough.

The American Dream is basically just the worst bits of Christian religious doctrine repackaged: if you do everything that's expected of you, you get to heaven/rich, so there's no point in trying to improve the lot of the damned/poor, since they deserve their fate and it would just be a distraction anyway, perhaps even making them try less hard (because why give everything for a goal that doesn't decide everything?) to escape it (the "moral hazard" theory). In fact, one of the joys of the blessed/rich is looking down on the suffering of the damned/poor.

It's pretty twisted, but it's always worked well with those trying to silence either their conscience or their despair. So it shouldn't come as any great surprise that the secular version (which still contains semi-mystical features like "The Invisible Hand") has had a resurgence along with the explicitly supernatural one, attracts the same crowd, and inspires similar levels of fundamentalism and calls for doctrinal purity - for example, compare the "Obama is a socialist" and Obama is a muslim" memes.

Nasty stuff, but it does explain how Christian Right came to be despite the Right being pretty much an antithesis - huge military, tough on crime, screw the poor - of anything Jesus said.

Re:Add it all up

[mcgrew]

We did not have a recession starting more than 4 years before 1979

Bullshit, the recession started when Ford was in office and didn't end until Reagan's 2nd term.

Re:Add it all up

[medcalf]

Well, part of my time growing up was lived in an impoverished semi-dictatorship, so it's not like I disagree, per se. However, "bad" in an absolute sense hasn't been a problem for the US since about 1864 in the North and 1870 or so in the South. But 1979 was and now is certainly bad in the sense of "in comparison to where we have been and could be," so I don't think I'm overreacting at all.

Re:Add it all up

[mcgrew]

Unlike Carter, Obama did nothing prior, during, and likely after his term

Indeed, I thought I'd never see a worse President than Carter, and I voted for him. Well, actually I voted against Ford. Unhappily, Bush proved me wrong about thinking I'd never see a worse President than Carter. Carter did nothing, but unfortunately Bush did -- got our country attacked, got us into two wars, couldn't catch Bin Laden (or seemingly anyone else), had gasoline prices more than quadruple, crashed the stock market and brought us into the worst economic climate since the Great Depression. And it only took him eight years!

Odd how people think Obama can fix a huge mess that was eight years in the making in only half the time it took to make the mess. How long does it take to clean your house after your eight year old's two hour party? You can't say he did "nothing"; one war is over, the other is winding down, the economy is slowly getting back on its feet, gasoline is still a tiny bit lower than the heights it rose to under Bush, Bin Laden is dead, and he did it despite a Republican Congress whose primary job was to make Obama fail. The only thing I fault Obama for is the health care bill; we need a system like Europe and Canada.

If you earn more than $200k per year and vote for Obama, you're a fool. If you make under $200k per year and vote for Romney (whose campaign platform is "do it like Bush did), you're just retarded.

Re:Add it all up

[Anonymous Coward]

Yeah but this is 2012 not 1979, what could possibly go wrong for crying out loud?

Move along...

[gubon13]

...nothing to see here...

No redundancy

[treymd]

Can they not have parallel backup pumps designed to leap into action when needed? Seems like some extra plumbing and monitoring hardware could help avert a costly shutdown.

Re:No redundancy

[corsec67]

But then what about the reliability of that backup hardware, especially if it isn't subject to the same kinds of loads as the primary?

At a certain point, "Shut everything down (safely)" is cheaper than having more redundant valvles, pumps, pipes, and more tubes in a series.

It is like RAID 1: you are more likely to have some kind of hard drive failure, but that hard drive failure is more likely to be recoverable.

Re:No redundancy

[Anonymous Coward]

Possibly depends on the nature of the system. There would be times you don't want it to automatically switch over, as you don't know if the pump failure was from the pump itself, or a problem someplace that would be common to multiple pumps, e.g. a damaged or blocked cooling line. It is just like how you can get circuit breakers that automatically reset after tripping... potentially bad if what tripped it before is going to get worse by reseting, although there are expensive that will try to reset when they are sure it can handle a few tries even with bad faults.

Re:No redundancy

[tangent3]

Says right there: "Its shutdown was caused when one of four coolant pumps for a reactor failed to work."

Could probably have continued operating on the remaining 3 pumps, but was shut down for safety.

Re:No redundancy

[Osgeld]

I would rather it shut down than have some pump and plumbing that hasnt been used since the 70's at random take the full force at any given time

but hey you go right ahead

Re:No redundancy

[treymd]

That to me implies that the normal situation is that all 4 pumps must be running, and they are not there for redundancy at all. If not, why have the other 3 pumps there at all?

Re:No redundancy

[Anonymous Coward]

Primary coolant pumps that work at 150 atmospheres aren't exactly cheap and you sure as hell can't hot-swap them, having a spare primary coolant loop would also give another possible point of failure. The unit probably could function with 3 pumps but for safety reasons they wouldn't risk it.

I can't think of any other industry where an equipment failure that leads to nothing but some downtime and expense for the company makes the headlines. Please /. stop reporting non-news.

Re:No redundancy

[treymd]

I would say routing testing and replacement would make this a non issue, but egghead corner cutters tend to think this is the place to cut corners, so I am inclined to agree.

Re:No redundancy

[Osgeld]

that and temporary testing is not a real measurement of long term performance

great it passed the 10 hour test, hows that going to hold when its the only path for a week?

Re:No redundancy

[fragMasterFlash]

That to me implies that the normal situation is that all 4 pumps must be running, and they are not there for redundancy at all. If not, why have the other 3 pumps there at all?

The answer to that question changed considerably when the Fukushima incident occurred. The entire nuclear power industry is held accountable for the failings of even the most reckless of its ranks.

Re:No redundancy

[Anonymous Coward]

Because it's a nuclear reactor? If it can work with two, you'll have four, and shutdown the instant one of them has problems.

Re:No redundancy

[sjames]

They ARE there for redundancy. For safety reasons, a reactor must not be operated without adequate redundancy. So, one of the redundant pumps failed and the system shut down in an orderly manner. That is necessary since it takes just a wee bit longer to swap in a cold spare pump than it does for a disk in a RAID.

It would be technically possible to run the reactor on 3 pumps but safety would be compromised.

The best way to know a pump will run is to have it running. That's why they keep all 4 running under normal conditions.

Re:No redundancy

[treymd]

If the backup fails then the system shuts down. as intended.

Re:No redundancy

[treymd]

The fact that it is a nuclear reactor means that it SHOULD have backups, and backups for those backups, and if that should fail, there is a backup for that. Perhaps NASA should run our nuclear power plants.

Re:No redundancy

[quenda]

They do have redundancy. The power station is connected by a grid to other power stations.
Normally they also have multiple reactors at one site, but for some reason TMI #2 has had an extended outage.

Re:No redundancy

[treymd]

That is actually sort of alarming to me since they probably install 4 identical pumps at the same time each with a rated lifetime that is about the same. So when the first fails, the others are surely soon to follow, And that takes us full circle to why if one fails, the system is designed to shut down.

Re:No redundancy

[jamesh]

Parkinson obviously hadn't imagined Slashdot when he proposed his Law of Triviality...

Re:No redundancy

[treymd]

I believe it was stated that #2 is so polluted that it is on permanent shutdown.

Re:No redundancy

[Anonymous Coward]

Having parallel pumps is very expensive. You can't just leave them alone, you've gotta test them all the time. Testing is regularly without causing brownouts is probably very difficult.

And it would only protect you from pump failure. There would still be other types of failure that can bring the system offline.

So, instead of parallel pumps, they just have enough power stations in other places to cover any individual station going offline.

Re:No redundancy

[sjames]

It's not THAT scary. Even assuming the pumps are all made exactly the same (I don't know that they are), failing 'at the same time' would mean within a year or two of each other.

I'm guessing (but it's a good guess) that one pump could manage when it has scramed.

Re:No redundancy

[Anonymous Coward]

Not if they run them at different intensities or don't run all the pumps all the time. For example they might power up the back-up pump every day for an hour to make sure it still works. Or they might run it all the time but only put it at full power for an hour a day.

Re:No redundancy

[Gordonjcp]

What happens when the cutover from one system to the backup system fails? How do you avoid a single point of failure? Yes, you could run both pumps in parallel at half power and devise some means of shutting off a failed pump and running the other at full power. That *still* introduces more complexity and more potential failures.

It's like they say about twin-engine aircraft - if one engine goes, the other has enough power to fly you right to where the crash happens.

Re:No redundancy

[Anonymous Coward]

Reactors run with 'inoperable' components all the time. Primary Reactor Coolant Pumps aren't one of them. They circulate core coolant in high volumes and they literally cost a fortune. When a PRCP trips you SCRAM, cool the core and figure out the problem. No fucking around. When you've figured it out the chairman of the NRC and the CEO of your power company is briefed.

There are four on that particular reactor, btw. All four must be 100% for the reactor to be allowed to operate.

I would love to be there once during a SCRAM. When a PORV on a B&W PWR lifts at full power the noise is heard for miles. A primal howl of super heated steam blowing out of the reactor. Every mope in earshot gets reminded of exactly what it is that makes that air conditioner spin.

The valve in question is that same one that stuck open leading to a Loss Of Coolant Accident in '79. It can only be actuated like 40 times. Nuclear reactors defy everyday experience; it's best if you don't indulge too much guesswork.

Re:No redundancy

[koxkoxkox]

You are right and I sure hope they are running like GP says they are. If you have backup pumps, of course you do not run them like the others. You shouldn't forget about them for twenty years hoping they will just wake up when needed, but running them full-time would be nuts.

Re:No redundancy

[Anonymous Coward]

It does, but for safety reasons the backups only run until the reactor can shut down.

Would you expect to run your servers as normal on UPS power, or would you use that power to effect a clean shutdown so you don't have problems when power is restored? It's exactly the same principle.

Re:No redundancy

[thegarbz]

Not just in nuclear but in the process industry in general to meet certain risk reduction goals for process safety redundancy is not enough. Redundancy can have failures and the failures require actions to be performed. The way this is typically done is when a piece of equipment has a failure in one of it's areas (say a safety PLC loses a processor card) a countdown timer starts to automated shutdown.

I look forward to seeing the full report on this.

Re:No redundancy

[Anonymous Coward]

no different than a four engine airplane, if you lose an engine it will fly just fine but you would still make a safety landing

Re:No redundancy

[omglolbah]

You do not wait for the pumps to hit the rated lifetime... You replace them in a revision/maintenance stop with time to spare.
If a pump fails you determine why, and if it is warranted replace it.

Re:No redundancy

[Anonymous Coward]

Unexpected things happen when components fail. News at eleven.

Re:No redundancy

[Zorpheus]

If safety require 4 pumps to run the reactor, why don't they just install 5 pumps then? Then they can keep the reactor running if one dies.

Re:No redundancy

[Anonymous Coward]

That to me implies that the normal situation is that all 4 pumps must be running, and they are not there for redundancy at all. If not, why have the other 3 pumps there at all?

So to you my RAID hot spare hard drives imply no redundancy at all, simply because I keep them spun up in order to be hot spares?

The problem with cold spare drives in comparison is you never know if the drive will function until you power it on. A hot spare however you know functions or not because it is already functioning!

Re:No redundancy

[Anonymous Coward]

There are no backups for the reactor cooling pumps. Every plant i have ever worked at all are run at 100% all the time It can run on only 3 but at reduced power. There are additional pumps that can be used to cool the core but not while at operating temp/press

Re:No redundancy

[Anonymous Coward]

there is no room to install additional pumps in teh containment building

Re:No redundancy

[Anonymous Coward]

Ive been at places with dual unit trips due to water leaking on a RCP breaker. the building shakes the lights go out and there is load noises but thats about it.
on a side note there is no steam in a PWR reactor if there is you have serious problems
also there are 4 PORV vales on the primary system which are never actuated except in an emergency 2 are electronically activated the other 2 operate on spring pressure they are one time use valves as far as i know.

During a SCRAM these valves are not actuated. The secondary turbine side valves open up

Re:No redundancy

[khallow]

why don't they just install 5 pumps then?

Because then they'd have to shut down when one of the (N+1) pumps fails.

Re:No redundancy

[drinkypoo]

great it passed the 10 hour test, hows that going to hold when its the only path for a week?

The obvious and straightforward way to handle this is to install redundant pumps, and switch back and forth between them on a schedule which also permits inspection and maintenance. You should have at least two of anything you can reasonably have two of. No, I don't care that it increases the cost. The cost of failure is much higher.

Re:No redundancy

[drinkypoo]

They do have redundancy. The power station is connected by a grid to other power stations.

Well, it's good thing that we cleared that up. I was worrying that redundancy was on-site, not piped in from elsewhere which Fukushima Daiichi proved is a total clusterfuck. I can rest easy knowing that the situation is completely fucked. Wait, what?

Re:No redundancy

[Anonymous Coward]

because the valving to be able to hot-swap a pump would make the system more complex and less reliable than a system with 4 pumps that scrams when it detects a failure. You really don't want to leave a failed pump in the system; there are all sorts of failure modes that indicate badness there.

Re:No redundancy

[quenda]

The point was that shutting down the reactor is not so bad because they have redundancy at a higher level.
For the same reason, if you have a large farm of redundant servers, you do not need redundant PSUs on each.

Re:No redundancy

[amorsen]

You are assuming failures are independent. Hopefully, when something fails at a nuclear power plant, they look at every similar unit with some suspicion. Having 5 pumps only helps if no common cause could ever cause problems for more than one at a time.

Re:No redundancy

[AmiMoJo]

Fukushima was connected to the grid for "redundancy" too. They also had a large stockpile of batteries on-site and an even larger one off-site. The former was not nearly enough and they couldn't get the latter to site when they needed it, even by helicopter.

Re:No redundancy

[MachineShedFred]

They were also idiots that put their backup diesel generators in the basement, while in a coastal floodplain.

They put those sons of bitches on the roof, and we're not having this discussion.

Re:No redundancy

[__aaqvdr516]

This is why, in the nuclear world, they have Quality Assurance paperwork and cradle to grave tracking. They have every test that was ever done to every component of that pump from the time of manufacture until present day. They will be looking at all the data. That "all" includes an awful lot.

Re:No redundancy

[bobbied]

That to me implies that the normal situation is that all 4 pumps must be running, and they are not there for redundancy at all. If not, why have the other 3 pumps there at all?

Using the Raid analogy, it's like having a RAID 5 array. When all the disk drives are working, your data is safe from a single drive failure. You have redundancy and can recreate all your data even if a drive fails. One of your drives then fails and you are no longer redundant, your data remains but you are no longer protected from *another* drive failure. When the data is important enough, you will simply shut down the system until full redundancy is restored.

Because the massive consequences of not providing cooling to a reactor, when the redundancy in the system was reduced the system automatically initiates the process to make the reactor safe, even without the remaining coolant pumps. This does not mean the reactor was ever in an unsafe condition, but that the redundancy of the protection systems was reduced so we shut it down to avoid problems caused by any additional failures.

Re:No redundancy

[bobbied]

But venting steam in the secondary loop is about the power generation side of the house shutting down and says nothing about the safety of the reactor components. Sure, there may have been some issues with the secondary steam loop and the shutdown may not have been as orderly as it should have been, but dumping steam is not an OMG it's melting down event.

Re:No redundancy

[quiet_guy]

Yes, normal = all four pumps running. In a PWR, your analyzed safety margins generally say "percent total flow through the core must be equal to or greater than total percent power."

So to get full output from the plant (100% power) you need 100% flow - all four running. One pump trips, and total flow goes to ~82% (hydraulics, pump heads, etc. Not a simple 75%.)

But power hasn't changed yet. 100% > 82%, automatic trips kick in and shut the plant down. You haven't damaged anything because the designed safety margins and trip responses take the transient into effect.

Can you run on three pumps? Sure, just not at full rated output. And since your job is to produce as much electricity as you can, the typical civilian plant is binary - either shut down or 100%.

Re:No redundancy

[Anonymous Coward]

Generally not how things work. Generally they ensure excess capacity so as to maintain a higher margin of safety. Its extremely likely three pumps are all that is required. Without having the excess cooling capacity means risk of something else cascading becomes much increased. As such, the reasonable thing to do is to simply scram the system and repair. Safety is maintained and everyone is happy.

It crazy how many people are going ape shit when things actually function properly.

Re:No redundancy

[tibit]

I can't but LOL when people seriously think no engineer has ever thought of that.

Safety engineering standards (like IEC 61508) define a concept of demand placed on a safety function. Typically it's broken down as low demand -- that's once a year or less frequent, high demand -- more frequent than once per year, and continuous demand. The lower the demand, the stringent the requirements for proof testing. Continuous demand systems have it relatively easy: they must monitor performance while on-line, and that's it.

Re:No redundancy

[vux984]

If safety require 4 pumps to run the reactor, why don't they just install 5 pumps then? Then they can keep the reactor running if one dies.

Because then you've just redefined safety as requiring 5 pumps.

Your argument makes sense to you; and it is perfectly logical, but all the public will see is that "someone said 5 pumps were required" and "only 4 are currently working".

"Clearly if there are 5, then 5 are required for safety, and 4 is not enough." -- better shut it down.

There is no number of pumps you could install to overcome this silliness.

Re:No redundancy

[digitalsolo]

Oh, I don't know. Huge generators on the roof during a massive earthquake and tsunami might not end well either. Gravity and all that.

Re:No redundancy

[Anonymous Coward]

the building shakes the lights go out and there is load noises but thats about it

Residents of both Middletown and Royalton near TMI heard the TMI-2 trip in '79. This very story mentions the "loud noise heard by nearby residents." Obviously there is less drama for those isolated inside a control room. Control rooms are designed to isolate operators.

on a side note there is no steam in a PWR reactor if there is you have serious problems

There must be steam in all operating PWRs, otherwise the system is `solid' and fails catastrophically due to hydraulic forces. A steam head is maintained using the Pressurizer for exactly this reason. There is also a residual steam bubble at the top of all RPVs in PWRs... there is no reason to make the vessel solid, no mechanism exists to bleed the bubble and thus it is always present.

During a SCRAM these valves are not actuated. The secondary turbine side valves open up

The following links document a few PORV lifts during reactor trips in the last 15 years. It is the Pressurizer PORV that often actuates to relieve pressure during reactor trips in B&W PWRs. This is routine.

        http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2010/20100609en.html
        http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2010/20100910en.html
        http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2000/20000214en.html
        http://www.nrc.gov/reading-rm/doc-collections/event-status/event/1999/19990816en.html

Depending on the design of the reactor, the power level and other factors some reactors MUST lift PORV at trip.

You are clearly ignorant of B&W reactor designs, TMI history and common operational events of PWRs. Please limit yourself to spectating on these topics.

Re:No redundancy

[Anonymous Coward]

I am not familiar with the specific TMI design but I assume most PWRs operate on the same basic principles. Running with an uneven amount of pumps would mean that the two primary loops would have different flow rates (one loop would have two pumps and one loop would only have one pump). Different flow rates through each primary loop is not something someone analyzed for so they they don't support operating like that. Different flow rates will cause a temperature differential between the two cold legs of water coming back into the reactor core, meaning the one cold leg with less flow would be colder than the other. With a temperature differential comes uneven mixing and that uneven mixing of coolant in the core would cause an abnormal neutron flux in the core and additional thermal stress. Basically, the reactor will make the same overall power output but certain parts of the core with the colder water would be making more power than other parts with the warmer water. This is not a good thing and not something taken into account with the design and safety models.

You could run with one pump in each loop at a reduced power level but now you are one failure away from a loss of coolant flow incident. Another option may be to isolate one of the primary loops and only operate on a single loop with two pumps. Again, I don't know the TMI design to know if that is possible.

Yep, and now

[Anonymous Coward]

And today the same thing will happen again. We will discover the problem and it will not happen again.

sux4them

[Anonymous Coward]

glad i don't know next to a radiation spewing nuclear power plant LOL http://www.youtube.com/watch?v=5K4_uHlTcTM

Re:sux4them

[MobileTatsu-NJG]

I think I get what you're saying, but I had to set Babelfish to 'youtube' to get a decent translation

Re:sux4them

[Zuriel]

This addon will translate Youtube comments for you.

Right...

[lightknight]

Nice shutdown, but I still think we need to move to more powerful passive safety devices. Using water as a coolant is awesome, but still prone to failure. Solid conduction, on the other hand...

Re:Right...

[jamstar7]

TMI is ancient technology. Nobody's built one of these things since TMI went online. They built using newer safer designs.

Of course, getting authorisation to shut down, decommission, and dismantle a reactor takes almost as much time, effort, legal fees, and money as building the damned thing in the first place. It's on the order of 4 acts of $DIETY and an act of Congress.

Re:Right...

[Anonymous Coward]

TMI is ancient technology. Nobody's built one of these things since TMI went online. They built using newer safer designs. Of course, getting authorisation to shut down, decommission, and dismantle a reactor takes almost as much time, effort, legal fees, and money as building the damned thing in the first place. It's on the order of 4 acts of $DIETY and an act of Congress.

You are talking without any real knowledge. If you did you would know that TMI was designed and built with a higher than normal Thermal Pressure containment ratio that most reactors of that era, which means a significantly larger containment ratio than the 'modern' (probably AP-1000) design you imagine yourself to be referring to.

If you knew that you would not have made that comment.

Re:Right...

[Anonymous Coward]

but I still think we need to move to more powerful passive safety devices

So would the entire nuclear industry. The problem is, its almost impossible to get them built anymore. What happens is the anit-nuclear crowd has scared the shit out of everyone so newer, safer technology is impossible to install. Even repairing and decommissioning has become extremely expensive because of the anti-nukers. Basically everything related to nuclear is more expensive and more dangerous because of anti-nukers.

Literally, you want to make the world a better place? Tell anti-nukers to sit down and shut the fuck up because adults are talking.

Fukishima came at really bad timing as newer, much safer, passively cooled designs were just starting to find their way into the world. Now that anti-nukers have scared the shit out of people we're once against forced to look at life extension for more dangerous and outdated designs.

Re:Right...

[tibit]

Why you think so? Any process plant is designed for a certain rate of catastrophic failures. No matter what technical means are used (passive vs. active safety, etc), it's engineered for that rate and no more. That means that no matter what devices are in use, it's not designed to be any more or less likely to cause a catastrophic event. If the failure rates used in probabilistic calculations in design diverge from real values, then you have an issue with your engineering process and passive safety is unlikely to help you fix that. Fukushima's design was a classic case of garbage in, garbage out. Nobody would have bothered with passive safety because there was no need for it. Had they identified the need, they'd have had passive safety as an option, but that's just one way to dealing with the effects of a tsunami, they might have simply put the damn backup generators and their fuel supply somewhere safe and that'd be the end of it -- with teh wicked active safety harr.

They posted a shot of the incident

[Grayhand]

http://3.bp.blogspot.com/_drqO7qJ_y4o/SrW1QkqR9wI/AAAAAAAAET4/4uV5HzzK9Ko/s1600-h/3mileisland.jpg

Re:They posted a shot of the incident

[Anonymous Coward]

Has anyone noticed that the spiral path of the laserbeam does not take into account the acceleration of the falling head due to gravity? The curves are perfectly parallel to each other, while they should actually stretch out in distance during the free fall.

Re:They posted a shot of the incident

[Anonymous Coward]

Has anyone not?

Re:They posted a shot of the incident

[EmagGeek]

Has anyone noticed that 9th grade physics assumptions, like that there is somehow a vacuum on the surface of the Earth, and that there couldn't possibly be upward thermal currents in a power plant's cooling tower, sometimes lead to a comment like, "has anyone noticed that the picture does not agree with my 9th grade understanding of physics? The horror!"

Re:They posted a shot of the incident

[Anonymous Coward]

Has anyone noticed that you are arguing about the physics of a fictional movie where a fictional human mutant can shoot lasers out of his head powerful enough to burn through concrete. Pissing contest!!!

Re:They posted a shot of the incident

[Anonymous Coward]

Deadpool vs. Three Mile Island? Someone get on Youtube and make the request!

I'ze so skaird

[Anonymous Coward]

I was so scared until I recalled that more people died at Chappaquiddick than at Three Mile Island.

Re:I'ze so skaird

[Anonymous Coward]

That is one way to look at it. The way I see it, half the people that potentially could have died at Chappaquiddick, died. If the same percentage die at Three Mile Island, it would be catastrophic. You should be *very* afraid.
 
PS: Stupid comments deserve stupid responses.

Re:I'ze so skaird

[tehcyder]

I was so scared until I recalled that more people died at Chappaquiddick than at Three Mile Island.

More people died in the 1918 flu pandemic than in the First World War, so therefore the war wasn't that bad.

Re:I'ze so skaird

[EmagGeek]

"PS: Stupid comments deserve stupid responses."

You certainly did not disappoint.

Re:I'ze so skaird

[Anonymous Coward]

"More people died in the 1918 flu pandemic than in the First World War, so therefore the war wasn't that bad."

No

More people died in the 1918 flu pandemic than in the First World War, so therefore the war wasn't as bad as the pandemic in terms of deaths.

There, fixed that for you...

Didn't even cause a blip

[Animats]

They had a reactor trip. Big deal. It didn't even show up as a power grid event that required emergency action in the PJM dashboard.

Welcome back Carter

[AntiBasic]

It's like 1979 all over again. I told you Carter would be a best case scenario for Obaaaaama

what even is

[nimbius]

the nuclear regulatory comission? ill wait on the IAEA, thank you...

er, wait...the IAEA doesnt investigate reactor faults in the United States. Because apparently american reactors just work.

Re:what even is

[tehcyder]

Because apparently american reactors just work.

They're designed by Apple? God help us all.

Re:what even is

[GameboyRMH]

Seriously could you imagine the horror? Function, safety and ease of repair sacrificed left and right without a second thought, in the name of aesthetics and "ease of use?"

It would make Chernobyl look like an engineering masterpiece.

"news worthiness"?

[SimplexBang]

Are nuclear installation incidents the only subject that has the validity of its "news worthiness'' discussed ? Is there an inverse proportionality rule that states that the small news shouldn't concern itself with larger problem areas ? Oh boy , we have a solar eclipse , big deal , nothing to see here ?

Re:"news worthiness"?

[Anonymous Coward]

"news worthiness" = can you instill fear, doubt or anger in your audience?

Re:"news worthiness"?

[tehcyder]

"news worthiness" = can you instill fear, doubt or anger in your audience?

Well in that case there would never be any Linux stories on slashdot would there?

X-men escaped.

[leuk_he]

They will never tell you one of the x-men/kids escaped. they might tell you that the invisible radiation inside has become too high , so nobody can check what really is going on.

If someone does spot something and report it, it will be mistake for fantasy.

The biggest secrets are all in the open....

'If radiation was released'?

[Anonymous Coward]

What is this? Come on America -are you turning into a load of cheese-eating surrender monkeys? The US should take pride in releasing the best and biggest cloud of radiation money can buy.

Re:'If radiation was released'?

[EmagGeek]

Sorry, that distinction belongs to Russia, for their Tsar Bomba detonation, which fell somewhere in the 50-100 megaton range.

Re:'If radiation was released'?

[Anonymous Coward]

Just like with the auto industry, Japan beat us again.

So how does that change nameplate efficiency?

[Anonymous Coward]

If unit 2 has been down since 79, that's GOT to be a large drop in the nameplace capacity.

I guess nuclear isn't reliable and you need more than nameplace power to use it...

Just like wind.

Not a meltdown!

[EmagGeek]

What idiot tagged this with "meltdown?"

This was not even close to being an "accident." Everything happened exactly the way it was supposed to. The control system detected a fault and shut down the reactor out of an abundance of caution.

No meltdown.
No radiation release.
No leakage of nuclear material.

Nothing to see here - at all. Move along.

Re:Not a meltdown!

[Anonymous Coward]

What idiot tagged this with "meltdown?"

This was not even close to being an "accident." Everything happened exactly the way it was supposed to. The control system detected a fault and shut down the reactor out of an abundance of caution.

No meltdown. No radiation release. No leakage of nuclear material.

Nothing to see here - at all. Move along.

What about tagging it:

fuckup

Re:Not a meltdown!

[GameboyRMH]

It's not a fuckup, it's a mechanical failure that happened safely.

Re:Not a meltdown!

[Anonymous Coward]

Failure to replace the part before it disintegrates is a fuckup.

Re:Not a meltdown!

[GameboyRMH]

How do you know when it's going to disintegrate? Even UV dye crack detection and X-ray examination aren't perfect. This could even happen to a newish pump.

Pansies

[smooth wombat]

I live within the 10 mile "danger" zone (cue Kenny Loggins) and lived through the initial incident in 79. In fact, I was out delivering papers every day during the entire incident.

This is nothing to be mentioned on a tech site. It has no relevance whatsoever other than the fact that the system did what it was supposed to.

Stop the panicking and hyperbole about how bad nuclear energy is. Compared to the amount of health related issues coal has produced, nuclear energy ranks about as dangerous as rabbit attacks

Re:Pansies

[cmdr_klarg]

about as dangerous as rabbit attacks

That is not an ordinary rabbit ... 'tis the most foul, cruel and bad-tempered thing you ever set eyes on. He's got huge, sharp-- he can leap about-- look at the bones!

Re:Pansies

[Anonymous Coward]

Well, now, uh, Launcelot, Galahad, and I, wait until nightfall, and then leap out of the rabbit, taking the French by surprise - not only by surprise, but totally unarmed!

Re:Pansies

[Anonymous Coward]

Yes, but billions of neutron size rabbits running near light speed may become dangerous...

Re:Pansies

[Anonymous Coward]

Funny enough, the last time we had killer rabbits and a Three Mile Island problem were during the Carter era.

Unfortunately, Carter is starting to look like a rapidly-receding "Best-Case" scenario, right now.

Re:Pansies

[digitalsolo]

Rabbit attacks? Clearly you have never seen Monty Python and the Holy Grail.

Re:Pansies

[Anonymous Coward]

Wait...

Wasn't the President attacked by a rabbit in 1979?

http://politicalticker.blogs.cnn.com/2010/11/21/jimmy-carter-explains-rabbit-attack/

Germany

[Anonymous Coward]

That is why Germany fades out nuclear technology. Too risky for a small industrialised nation and not future-proof. Better become a leader in the next energy revolution. Solar pope Hermann Scheer explained.

Re:Germany

[dywolf]

Nothing is future proof. Everything, particularly mechanical things, breaks down and needs repair replacement eventually. That what constant inspections and preventative maintenance are for. Nuclear plants are no different.

Re:Germany

[Anonymous Coward]

No, it is public perception of nuclear power. The real measurable dangers of fossil fuels from ground where they have been sitting for millions of years to the final end point of gases being released to the atmosphere after burning the refined products are very dangerous too. The risks are real and more actual deaths occur. It's funny to hear someone with a pack of cigaretts in their pocket discuss the health risks and concerns of nuclear power. For some reason, many people do not have the ability to look outside the box or they really do not understand the real world impact of things they abitrarily consider "safer". A lot of people are against nuclear power, fossil fuels, and other forms of creating electricity for various reasons but the bottom line is we have to generate power with some method that is technically possible and cost effective right now. In my opinion, nucelar power from a pressurized water reactor is a reasonable choice right now. Remeber, TMI did have a major accident in the past and I used to be a nucelar operator so I've been forced to study the event and even give lectures on it many times over. It was not and never was a real safety threat. An airline pilot gets more radiation exposure above background on a single flight than anyone around TMI gets above background in a single year. I can think of 20 other chemical plants in the area that could have caused actual loss of life and created a much larger long term environmental impact.

more like if mr burns did not cut corners to save

[Joe_Dragon]

more like if Mr burns did not cut corners to save on costs.

Why is this a story?

[J'raxis]

Why is this a story?

Because a simple mechanical device failed? Wow, that's news. Because the safety measured at the plant functioned exactly as designed? Yup, that's certainly news. Because the residents in the area heard a loud noise? Stop the presses!

Or because when anything happens at a nuclear power plant---including it functioning exactly as designed---the anti-nuclear luddites and other assorted fearmongers leap on the (non-)story in order to push their agenda?

Hack?

[Anonymous Coward]

After all the news about the escalation of cyberwarfare tactics my very first question about this event is, was it a hack? Maybe I should stop reading the news. :/

Winner of the word twisting beyond obvious prize

[dbIII]

Water is available in the phases of steam, liquid water and ice. No ice touches those blades either, but I thank you for your pretended misunderstanding.