Thread: Nuclear power plant worries continue to grow in Japan as effects from deadly tsunami

This is interesting. Im curious whats going on over there? it doesn't explain really well what's happening. It says the cooling system is messed up, but all plants come with redundant systems. and how is the US going to deliver coolant to the plant that Japan couldn't? I get the impression this writer doesn't know shit about nuclear power and is doing a poor job reporting on whats really going on?

Originally Posted by bio-chem

This is interesting. Im curious whats going on over there? it doesn't explain really well what's happening. It says the cooling system is messed up, but all plants come with redundant systems. and how is the US going to deliver coolant to the plant that Japan couldn't? I get the impression this writer doesn't know shit about nuclear power and is doing a poor job reporting on whats really going on?

i think the writer has other motive

3 nuclear reactors in trouble after Japan quake - World news - Asia-Pacific - msnbc.com

TOKYO — Coolant systems failed at three quake-stricken Japanese nuclear reactors Saturday, sending radiation seeping outside one and temperatures rising out of control at two others.
Radiation surged to around 1,000 times the normal level in the control room of the No. 1 reactor of the Fukushima Daichi plant, Japan's Nuclear and Industrial Safety Agency said. Radiation — it was not clear how much — had also seeped outside, prompting widening of an evacuation area to a six-mile radius from a two-mile radius around the plant. Earlier, 3,000 people had been urged to leave their homes.
Tokyo Electric Power Co. said Saturday that the temperatures of its No.1 and No.2 reactors at its Fukushima Daini nuclear power station were rising, and it had lost control over pressure in the reactors.

Fukushima Daini station is the second nuclear power plant the company has in Fukushima prefecture in northeastern Japan, where the troubled Fukushima Daiichi plant is located.
Tepco said at about 2:46 p.m. local time three of its six reactors shut following the earthquake. All are boiling water reactors.
Tepco said the reactors shut due to the loss of offsite power due to the malfunction of one of two off-site power systems. That triggered emergency diesel generators to startup and provide backup power for plant systems.
About an hour after the plant shut down, however, the emergency diesel generators stopped, leaving the units with no power for important cooling functions.
Nuclear plants need power to operate motors, valves and instruments that control the systems that provide cooling water to the radioactive core.
Earlier, Chief Cabinet Secretary Yukio Edano said, "Residents are safe after those within a 3-kilometer (1.8-mile) radius were evacuated and those within a 10-kilometer (6.2-mile) radius are staying indoors, so we want people to be calm."
The country's nuclear safety agency said pressure inside one of six boiling water reactors at the Fukushima Daiichi plant near Onahama, some 170 miles northeast of Tokyo, had risen to 1.5 times the level considered normal.

Originally Posted by bio-chem

This is interesting. Im curious whats going on over there? it doesn't explain really well what's happening. It says the cooling system is messed up, but all plants come with redundant systems. and how is the US going to deliver coolant to the plant that Japan couldn't? I get the impression this writer doesn't know shit about nuclear power and is doing a poor job reporting on whats really going on?

I've been watching CNN all day and they aren't explaining shit!

ok, so that adds a little bit to the picture. i wonder why the diesel generators stopped after only an hour? under those conditions things would go down hill pretty quick. temperatures will rise but 1.5 times normal isn't catastrophic. the thing is radiation levels in a control room are the same as radiation levels in your homes. 1000X is potentially alarming depending on what those levels really are currently. honestly worse case scenario in my mind they end up shutting down those plants, but i don't really see radiation being released outside the plant. it's pretty fucking expensive no doubt, but Chernobyl we aren't dealing with here

Originally Posted by Jodi

I've been watching CNN all day and they aren't explaining shit!

That's the norm for CNN, IMO.

But, I'm not sure a lot of info is in the hands of those outside of the nuclear people in Japan.

I just read that it's now 5 reactor with "problems."

This could be something.

We'll wait and see. (Could be an "oh sh*t.")

Excuse my ignorance, but in such an area prone to earthquakes they built nuclear reactors.

Pretty short-sighted and/or naiive, IMO.

Originally Posted by Big Smoothy

We'll wait and see. (Could be an "oh sh*t.")

Excuse my ignorance, but in such an area prone to earthquakes they built nuclear reactors.

Pretty short-sighted and/or naiive, IMO.

The "Oh Shit" is with the inability to get the Diesel generators back on line. Obviously they are not releasing much information so it's hard to tell whats going on. the way these things are built natural disasters aren't the issue. I mean an 8.9 earthquake hits and the reactor itself is just fine apparently. shows the damn thing is bulletproof. the problem is that both external and backup power to pump cooling water into the reactor has stopped. and we are not given the reason why. even when a plant "scrams" all control rods are inserted and fission stops in the reactor "decay" heat is still being produced and coolant is still needed. they need to get some damn electricity to those pumps.

Originally Posted by Big Smoothy

That's the norm for CNN, IMO.

But, I'm not sure a lot of info is in the hands of those outside of the nuclear people in Japan.

I just read that it's now 5 reactor with "problems."

This could be something.

We'll wait and see. (Could be an "oh sh*t.")

Excuse my ignorance, but in such an area prone to earthquakes they built nuclear reactors.

Pretty short-sighted and/or naiive, IMO.

I'm sure its bush'e fault

Originally Posted by Dark Geared God

I'm sure its bush's fault[IMG]:

Originally Posted by bio-chem

Originally Posted by bio-chem

ok, so that adds a little bit to the picture. i wonder why the diesel generators stopped after only an hour? under those conditions things would go down hill pretty quick. temperatures will rise but 1.5 times normal isn't catastrophic. the thing is radiation levels in a control room are the same as radiation levels in your homes. 1000X is potentially alarming depending on what those levels really are currently. honestly worse case scenario in my mind they end up shutting down those plants, but i don't really see radiation being released outside the plant. it's pretty fucking expensive no doubt, but Chernobyl we aren't dealing with here

How to Cool a Nuclear Reactor
Japan's devastating earthquake caused cooling problems at one of the nation's nuclear reactors, and authorities scrambled to prevent a meltdown
The 8.9 magnitude earthquake in Japan is causing problems for at least one of its fleet of nuclear reactors—and authorities have shut down 10 of the country's 55 units. Tokyo Electric Power confirmed that pressure had been rising inside reactor No. 1 at its Fukushima Daiichi nuclear power plant on the northeast coast, one of the largest nuclear power plants in the world. That means cooling water is not getting to the reactor core, causing a build up of steam inside the containment vessel. The problem, according to Japanese media reports, is a loss of grid electricity to run the pumps that bring in cooling water. The backup diesel generators that are supposed to provide emergency power in that case are out of order, according to the Japan Atomic Industrial Forum, but replacements were being taken to the plant. (Similar diesel generators were providing power to the nation's Rokkasho Reprocessing Plant, which recycles spent nuclear fuel.)

As a precautionary measure, the Japanese government has declared a nuclear emergency and asked people living within three kilometers of the facility to evacuate and people living within 10 kilometers to remain indoors. Tokyo Electric Power, for its part, planned to vent some of the radioactive steam from inside the containment building.

Scientific American spoke with Scott Burnell, public affairs officer at the U.S. Nuclear Regulatory Commission (NRC), the government agency charged with monitoring the safety of the 104 nuclear reactors in the U.S., about what it takes to cool down a reactor.

[An edited transcript of the interview follows.]

How do you typically cool a reactor?
The approach to cooling is very simple: push water past the nuclear core and carry the heat somewhere else. The chain reaction that actually runs the reactor can be shut off in a matter of seconds. What's left over in the core, the radioactive material, will continue to give off heat for a long time. Unless you have a mechanism to remove that, the heat can build up and can eventually damage the radioactive fuel or the reactor.

Pushing water past the core means pumps that are generally run by electricity. What happens when a reactor gets disconnected from the grid?
There are emergency diesel generators. You also have a battery system to keep instruments running, but that can also provide power to safety systems [which prevent a meltdown by cooling the reactor core]. It's all meant to provide defense in depth. First you rely on the grid. If the grid is no longer available, you use diesel generators. If there is an issue with the diesels, you have a battery backup. And the batteries usually last long enough for you to get the diesels going.

How much time is there before a meltdown?
It depends on the plant. It depends on whether it's a boiling-water reactor or a pressurized-water reactor. Basically, [in both] you have the benefit of natural forces such as convection. There is a coolant loop no matter what, so you end up to some degree cooling the core because the heated water rises and colder water gets pulled in. But that's not as effective as a pump bringing in cool water. Just to speak very broadly, you have many hours to restore power to the system to get normal cooling going. It's really not possible to get more specific than "many hours."

But generally, less than 24 hours.
That's fair to say.

What's the worst-case scenario?
The event we are looking to avoid is damaging the core. Once you start damaging the core, you are then releasing radioactive material into the coolant and thereby increasing the chances that something travels outside the reactor.

The reactor that was not cooling properly in Japan, the Fukushima Daiichi No. 1 reactor, was a boiling-water type. How are these different from pressurized-water reactors in terms of cooling?
Particularly useful to boiling-water reactors is a system that is steam driven. It does not require an outside power source. Steam generated by the heat of a cooling down reactor has enough force to run a turbine, which then runs a pump that provides coolant to the core. That sort of system is supposed to withstand an earthquake, and that can run for an extended period. It's a self-limiting condition. That system does use batteries for the controls, but it can also be operated manually. So even in the face of a complete station blackout—you don't have any power at all—there are methods for using the steam-driven pump to continue to keep cooling going.

Are there other coolants besides water?
Water would be it, essentially. The reserve tanks at a reactor contain the same grade of water in terms of purity and chemical composition that are normally used in the core. It is possible, if you have a situation where you have exhausted that source of coolant to introduce, quote–unquote, regular water. That will do the job of cooling.

Why do nuclear power plants need electricity to be cooled?
Nuclear reactors are net positive in terms of supporting the grid. They produce much more electricity than they need to run their systems. As a basic design feature in the U.S., plants are not literally self-powering. That's by design, because you don't want to end up in a situation where a problem at the plant cuts off its own power source. Therefore, the primary means of power for a plant in order for it to run is electricity from the grid. As a general matter, for U.S. plants, if you can't use power from the grid, you shut down.

What kinds of events could knock out a diesel generator?
You always have the possibility of just plain old failure. That's why you have multiple diesels at a plant for redundancy's sake. It can be the case that diesel itself is running properly but the distribution system, the buses or the cabling could be misaligned to the point where the diesel detects that its power is not being accepted by the plant. It's not going to run if it's trying to generate power and that power's not going anywhere. When we say a diesel fails, it's not always a problem with the diesel [itself].

How long does it take to cool down a reactor?
There are design specific variables there. The easiest way to answer that question is that NRC regulatory requirements for emergency power supplies is that they be available on the order of a month. You can render a plant in an acceptable condition within a few hours. However, heat is still being generated. If you had to stop, at any point, carrying away that heat, it would start building up again. Emergency cooling systems have to be available for weeks.

I think every reactor should be built deep underground or in sides of mountains just for this reason, I don't care how many protective measures are taken it's a dangerous game we play, I think the biggest problem here is that it was built to withstand Japan's historic earthquakes in the 7. to lower 8. range and this one was off the scales, then we got to worry about in times of war they can be used against us, just a regular bomb could be used to blow these things and do much worse destruction.....

Originally Posted by maniclion

, I think the biggest problem here is that it was built to withstand Japan's historic earthquakes in the 7. to lower 8. range and this one was off the scales, then we got to worry about in times of war they can be used against us, just a regular bomb could be used to blow these things and do much worse destruction.....

I don't know the specifications of this reactor being built to withstand 7-8 earthquakes, but not higher. This earthquake was an 8.9 and I've not read anything that states there was structural damage to the plant/core/reactor vessel. If there is I'd love to see it.

I also don't think its smart to post untrue information about 'regular bombs' being able to "blow these things and do worse destruction" that part just simply isn't true. bunker busters would have trouble doing enough damage to open up the core.

Mino. nice job of posting factual information out there for people to educate themselves on the issue of nuclear power safety.

Originally Posted by bio-chem

Mino. nice job of posting factual information out there for people to educate themselves on the issue of nuclear power safety.

I also learned something....which will definitely ooze back out of my brain.

Originally Posted by min0 lee

I also learned something....which will definitely ooze back out of my brain.

Keep hanging on son, I'll learn you something.

Originally Posted by min0 lee

Keep hanging on son, I'll learn you something.

The govt is most definately worried. They have been loading the locals with iodine pills so their thyroids don't absorb the radiation. Very scary situation.

Kinda reminds you of how dangerous nuclear power can be

Originally Posted by BlueLineFish

The govt is most definately worried. They have been loading the locals with iodine pills so their thyroids don't absorb the radiation. Very scary situation.

there are two very specific things to talk about when dealing with radiation. radiation contamination, and radiation exposure. iodine pills only help when there is a concern of internal radiation contamination. like eating food with radioactive material in it. iodine pills do nothing for radiation exposure such as an x-ray will give. right now i've not read anything that says radiation contamination has left the plant systems. anyone have any kind of information otherwise? right now there is a massive misunderstanding of radiation/radiation exposure/nuclear power. this is a very bad accident. absolutely it is going to cost a lot of money. however i've yet to read anything credible that shows danger to the populace.

I just saw on the news that 17 people have tested positive for contamination with 3 being seriously contaminated.

Originally Posted by BlueLineFish

I just saw on the news that 17 people have tested positive for contamination with 3 being seriously contaminated.

are these employees? and was this internal contamination? as long as this is not internal contamination a simple shower can take care of contamination. Does everyone here realize that eating a banana provides internal radiation? bananas are high in potassium and potassium has a naturally occurring radioactive isotope. so much education needs to be done on this subject. I hope people take this as an opportunity to educate themselves so they know what the real dangers are here

As usual news didn't say. Keep up the scare tactics. I am aware of the differences between the two forms of contamination as a have training from work.This entire ordeal should be a wake up call for us here. Japans nuclear regulations and program is more advanced and more strictly regulated than ours here

Originally Posted by BlueLineFish

Japans nuclear regulations and program is more advanced and more strictly regulated than ours here

I've not seen any evidence of this in my experience. I've worked with and spoken to quite a few guys that have done outages both here and in Japan and other countries. Japan is different for sure, but not more regulated or advanced

I read that in a few places but obviously sources may be flawed. If I am not mistaken they rely far more on nuclear power than we do. Is this not correct?

Originally Posted by bio-chem

I've not seen any evidence of this in my experience. I've worked with and spoken to quite a few guys that have done outages both here and in Japan and other countries. Japan is different for sure, but not more regulated or advanced

The real problem is that those particular plants are designs that are over 40 years old and don't even have the second cover that 3 Mile Island did. If they at least had that, it would be so much less of an issue.

It would be a non-issue if they plants were completely modern.

But, oh no! It's nuclear!

On a morbidly funny note, at a news site that I use, the story has been tagged with "Godzilla".