The short answer is, longer than you think.
For the longer answer you’ll have to visit what if?, a delightful web site that answers hypothetical physics questions.
Want to take a dip? (what if?)
at least darkness would not end the fun…..
And if the pool runs dry, you won’t need a bathing-suit.
“Without cooling, the fuel pool water will heat up and boil. If the water boils or drains away, the spent fuel assemblies will overheat and either melt or catch on fire. NRC studies have estimated that many thousands of people living within 50 miles could die from the radiation released when spent fuel assemblies melt or catch on fire.”
Spent Reactor Fuel Security
If you can’t take the heat, stay out of the kitchen. Or pool. Or whatever.
It depends on the type of reactor.
The newer designs all have passive cooling – which means they go into shutdown without any pumps needed.
We don’t use graphite in US reactors, so fires are not going to be an issue.
Oh, ans if Houston had a 9.0 Earthquake, the nuclear plants would be the least of our worries. 9.0 would flatten Houston. I can’t say this strongly enough – FLATTEN.
In Japan, one person died from the nuclear plants problems, and 20,000+ died from building on the ocean in a tsunami zone.
They will not rebuild the nuclear plants, but they are rebuilding right on the ocean again.
So clearly logic is not part of the discussion.
I compare it to flying vs driving. Flying seems more dangerous, but it’s safe. Driving seems safe, but it’s dangerous.
re: “It depends on the type of reactor.”
Do you even know what a spent fuel pool is, amigo?
New Images Reveal Nuclear Fuel Rack Exposed to Air
re: “The newer designs all have passive cooling – which means they go into shutdown without any pumps needed.”
You still need power for your ultimate heat sink.
Containment Failures and the Loss of the Ultimate Heat Sink
re: “We don’t use graphite in US reactors, so fires are not going to be an issue.”
Zirconium alloys which are used to clad nuclear fuel rods burn when exposed to oxygen. And such a fire in a spent fuel pool at STP or Comanche Peak could make large areas of Texas uninhabitable, maybe even Katy.
“Brookhaven National Labs did a study back in 1998 about this and they estimate that over 180,000 cancers would result from a fuel pool fire and that an area of about 40 mile radius would have to be permanently evacuated.”
Can Spent Fuel Pools Catch Fire?
re: “Oh, ans if Houston had a 9.0 Earthquake, the nuclear plants would be the least of our worries.”
Tell that to the permanently evacuated citizens of Fukushima Prefecture.
Fukushima Daiichi: The Truth and the Future
IANVS – One Nuclear Plant meltdown like Fukishima isn’t going to make “much of Texas uninhabitable”.
The Fukishima no-go zone is down to 10 mile radius. Past 20 radiation is at acceptable levels.
A mere 10 miles.
So the Bay City nuclear plant would be all the way to … Bay City in the temporary unihabitable category. 10 miles is a speck in terms of Texas distances.
Also, do you have any idea just how powerful a 9.0 Earthquake is? We could see deaths in the hundreds of thousands and injuries well over a million if it hit Houston.
Of course it won’t hit Houston.
Or should I say the odds are really low.
The coating on the rods isn’t going to burn much or long. Look at how small the area is in Fukishima.
I get it, you fear nuclear power and grasp at anything to instill fear where there is little actual damage from the technology.
The Fukishima plant was a 50 year old design. They didn’t even have electric calculators when they made it. Yet it went through a record eathquake and massive tsunami, and what, maybe 1 person died from it??
Things have improved in the safety dept since the 1960′s.
Cars have seatbelts, airplanes crash far less – and nuclear power is far safer.
Wind power has killed hundreds of times more people in the US than nuclear power (we get a few deaths every year in wind construction/maintenance).
Try using logic instead of fear. Fear is animal based emotion.
You will get in a car, and consider it safe to drive to the kwiky mart for a slurpee.
Yet they danger from that drive exceeds the danger from nuclear power in the US.
And like I said, 20,000+ died from building on the ocean in a tsunami zone – but people like you would build in the exact same spot as long as they shut down the nuclear power plants nearby.
That makes sense to you?
Not to mention hi-temp Zirconium-steam reaction that releases high concentrations of hydrogen:
Zr + 2 H2O → ZrO2 + 2 H2
And when H2 gas mixes with O2 in the air & ignites, Boom!
“This reaction was responsible for a small hydrogen explosion accident first observed inside the reactor building of Three Mile Island nuclear power plant in 1979 that did not damage the containment building. This same reaction occurred in boiling water reactors 1, 2 and 3 of the Fukushima I Nuclear Power Plant (Japan) after reactor cooling was interrupted by related earthquake and tsunami events during the disaster of March 11, 2011, leading to the Fukushima I nuclear accidents. Hydrogen gas was vented into the reactor maintenance halls and the resulting explosive mixture of hydrogen with air oxygen detonated. The explosions severely damaged external buildings and at least one containment building. Many pressurized water reactor (PWR) containment buildings have catalyst-based recombinator units installed to rapidly convert hydrogen and oxygen into water at room temperature before the explosive limit is reached.”
Over here …
In reply to this and other comments below:
It’s not true, or given, that the cladding in pools like South Texas would melt or burn even in the case of complete pool drainage. The conclusion of a National Academy of Scientists on the issue concluded that this *might* be an issue at only a few US plants (mainly old BWRs, not the South Texas PWR). All the recommended was further studies for those few pools.
In reality, the possibility of cladding fire or melt is quite dubious, the product of extremely simplistic and grossly conservative (pessimistic) analysis. The same is true of the consequence studies you reference (from Brookhaven, etc…)
The way analyses are done in the nuclear field is to assume absolute “bounding” (i.e., unrealistically conservative) values for all input parameters. The final results of such analyses are grossly over-conservative (pessimistic), often by orders of magnitude. I know this because I often perform such analyses.
As an example, reactor meltdown health consequence estimates (by organizations such as NRC, Sandia, or Brookhaven) have been repeatedly shown, by TMI, then by Chernobyl, and then by Fukushima, to be overly conservative by orders of magnitude. Such studies maintained, for decades, that thousands of immediate deaths and tens of thousands of cancer deaths down the road would result from a severe meltdown of an LWR (Western) nuclear plant. The result of Fukushima, the complete meltdown of not one but three large LWRs? No public deaths and no projected, measurable long-term health consequences.
So, forgive me if I take your NRC or Brookhaven estimates with a pound of salt.
Given all this, it is indeed true that a meltdown (or pool drain) would be the least of Houston’s worries in the case of a 9.0 earthquake, given that thousands would die whereas the meltdown would cause no deaths and have no measurable health impacts. And don’t forget, the earthquake didn’t cause the Fukushima meltdown, the tsunami did. South Texas (a newer, better plant) would be even more able to take such an earthquake, and tsunami, not that there is any chance of either happening in the Gulf area.
What would I “tell” Fukushima residents? Having to move (temporarily) from one town to another beats the hell out of being dead. Not only did the earthquake and tsunami kill ~20,000 people, but the alternatives to nuclear (i.e. fossil power plants) cause ~20,000 deaths in the US alone ANNUALLY, and ~1000 deaths every single day, worldwide.
Finally, the chance of full drainage is almost non-existent. It takes days for the pool to boil off. That’s plenty of time to establish power and/or cooling. Even spraying water in with a hose is sufficient. That’s what they did in Japan. On top of this, the US industry is now taking additional steps to ensure the ability to maintain cooling of spent fuel pools.
re: “The way analyses are done in the nuclear field is to assume absolute “bounding” (i.e., unrealistically conservative) values for all input parameters. The final results of such analyses are grossly over-conservative (pessimistic), often by orders of magnitude. I know this because I often perform such analyses.”
And, as you probably also know, such “absolute “bounding” (i.e., unrealistically conservative) values for all input parameters” produced final results that were “grossly over-conservative (pessimistic), often by orders of magnitude”, for Fukushima Daiichi, right up until the time of its multiple reactor meltdowns, spent fuel pool failures, & hydrogen explosions.
And is it not also true that our National Academy of Sciences (NAS) reported that, for BWR’s & PWR’s alike:
“a partially or completely drained pool could lead to a propagating zirconium cladding fire and release large quantities of radioactive materials to the environment.”
And that exposed fuel cladding could heat up & ignite to release aerosols of harmful radionuclides?
“If the water level is above the top of the fuel racks, decay heat in the fuel could cause the pool water to boil. Once water levels fall below a certain level in the fuel assembly, the exposed portion of the fuel cladding might heat up sufficiently to ignite if no mitigative actions were taken. This could result in the release of a substantial fraction of the cesium inventory to the environment in the form of aerosols.”
And that a zirconium cladding fire with steam could generate hydrogen gas that could make things much worse?
“A zirconium cladding fire in the presence of steam could generate hydrogen gas over the course of the event. The generation and transport of hydrogen gas in air was modeled in the Sandia calculations as was the deflagration of a hydrogen-air mixture in the closed building space above the spent fuel pool. The deflagration of hydrogen could enhance the release of radioactive material in some scenarios.”
And that radionuclide releases from spent fuel pools at PWRs (like those in South Texas & San Onofre) could possibly be more severe than spent fuel pools at BWRs (like those at Fukushima Daiichi & 23 U.S. nuclear reactor plants)?
“There are reasons to believe that the results for a PWR pool could be somewhat different and possibly more severe, than for a BWR pool: PWR assemblies are larger, have somewhat higher burn-ups, and some assemblies sit directly over the rack feet, which may impede cooling.”
Safety & Security of Commercial Spent Nuclear Fuel Storage: Public Report (2006)
And is it not also true that the typical spent fuel pool at U.S. BWRs or PWRs holds multiple metric tons more of highly radioactive spent reactor fuel than the spent fuel pools at Fukushima Daiichi Units 1, 2, 3, or 4?
Risk From Spent Nuclear Reactor Fuel Is Greater in U.S. Than in Japan
re: “Finally, the chance of full drainage is almost non-existent.”
Finally, no doubt, that was the same thinking at Fukushima before the earthquake took out site power & 40 minutes later the tsunami took out the emergency diesels, cooling to the spent fuel pools, & the seawater pumps (i.e., the ultimate heat sink), precipitating multiple catastrophic reactor meltdowns, spent fuel pool failures, & massive hydrogen explosions?
Accident Overview at Fukushima Daiichi NPS
And it’s now been disclosed to the public that nuclear industry regulators were well aware, since at least 2007, of the extraordinary vulnerability of multi-reactor nuclear stations to Station Blackouts (SBO) from earthquakes & flooding, like what occurred at Fukushima Daiichi.
“What If” is a great blog, and I find delight in every week’s posts. Of course, pair it up with the original XKCD, and you get three days a week of good geek humor!
Ditto JAy. I’d never seen What If before, but was familiar with XKCD. THIS is why some of us believe that science can be so very fun.
re: “The coating on the rods isn’t going to burn much or long.”
Not coating, pilgrim, cladding — the metal alloy that holds the nuclear fuel together.
And after several decades working in the nuclear industry, we don’t fear the technology, but we are well aware of its limitations & inherent dangers, especially in an earthquake-fault zone with millions of people.
And its costs.
Customers have paid more than $1 billion for idle San Onofre plant.
Wanna go swimming?
Isotope this never happens in Texas, at least not in my half-lifetime.
Fission for a laugh there, Carp?
there’s always one.
Dose rates near the surface of spent fuel pools are ~2.5 milliRem per hour. Your total dose has to be ~10 Rem before any significant effects on health (including future cancer risk) are seen. Thus, you could swim in a spent fuel pool for ~4000 hours w/o any significant risks or impacts, as long as you don’t dive down. Dose rates increase very rapidly as you go down!
Don’t worry about a 9.0 earthquake in Houston. There is a 0% chance of that happening. High magnitude quakes (there has never been a 9.0 in recorded history) almost always occur along and near plate boundaries…and we’re not near one. We have 10′s of thousands of feet of sands and shales below us, we could feel ground motion (Houston did feel some minor motion from a tremor in Mexico some years ago) but we’ll not experience the sharp shocks of a high magnitude quake below us.
If I filled my pool at my house in Katy with nuclear fuel, would I need to evacuate?
Took along time for the first Katy joke. I’m surprised.
But, for this particular Katy joke the true answer is “yes.”
My neighbor in Katy just filled his pool with nuclear fuel and invited me to take a swim. Should I accept his invitation or evacuate?
Didn’t you mother ever teach you not to evacuate in someone’s pool?!? 8-0
Just beware the nuclear allegators.