China Syndrome

[trex]

http://www.nytimes.com/2013/09/01/world/asia/radiation-near-japanese-plants-tanks-suggests-new-leaks.html?_r=0

About 430,000 tons of contaminated water, or enough to fill 170 Olympic-size pools, are stored in rows of tanks at the plant, which appears to be running out of open space to put them all. The contaminated water increases by 400 tons every day as groundwater flows into the basements of the damaged buildings housing the three ruined reactors, which melted down in the worst nuclear accident since Chernobyl in 1986.

Tepco must draw off that water to prevent it from overwhelming jury-rigged cooling systems that keep the reactors’ melted cores from reheating and melting into the ground in a phenomenon known as the China syndrome. Tepco has struggled to safely handle and store all the water.

Is it likely that the damaged reactors' core will heat up again and cause a similar meltdown like in the Chernobyl case?

 

[flecc]

Newspapers love to exaggerate and misreport, so it's important not to be bamboozled.

Firstly Fukusima was a tsunami accident, not a nuclear accident, the nuclear repercussions a byproduct of the original accident. Certainly it's difficult to deal with, but very far from the disaster the media make it out to be.

The USA's Three Mile Island accident was a nuclear one, the second of the the major ones that the world has seen, and it's nature was identical to that at Fukushima in that it was the absence of cooling water that caused the meltdown problem for it's reactors. That was satisfactorily cleaned up and no-one ever mentions it now, most people probably don't know or even remember it happening in 1975. The relevant facts that newspapers don't report and almost certainly don't know or want to know are as follows:

The important thing to note with Three Mile Island and Fukushima that the nuclear vessels have not been breached and will not be in Fukushima's case.

The fuel in that age of BWR reactor lasts for three years and one third is changed annually. Therefore in the worst case a third of the fuel had three years life left in it, a third had two years and a third has one year. The accident occurred over two years ago so the active fuel content is now less than one third, further greatly reduced by the melt so far. So it's a rapidly reducing problem, the heat production will continue beyond that one year but it's management getting ever easier over time.

Since the nuclear vessels were not breached, the radioactivity produced was secondary, produced by heat fractioning the remains of the cooling water and the resultant gasses carrying caesium 137 and iodine 131 pollution into the air. The quantities were low as indicated by the small exclusion zone that remains, and iodine 131 has an 8 day half life. After 200 days it's barely measurable and since iodine tablets were issued to all the affected population it can cause no illness. The caesium 137 half life of 30 years means the current small exclusion zone must remain in place long term.

The Tsunami accident killed 20,000 people, the nuclear radiation byproduct has killed no-one, yet it's the latter the newspapers and public rabbit on about, barely mentioning the former. The comment is clearly driven by bigotry, fear and ignorance.

The Chernobyl RBMK accident did breach reactor number 4 which did melt down, but it did not melt down into or through the earth. So there is no "China Syndrome", that being a scientifically ignorant concept of a very silly Jane Fonda Hollywood movie.

How many people know that the Chernobyl nuclear power station resumed production from the adjoining reactor number 1 just 12 weeks after the accident and continued to supply the Russian grid for 14 years through to year 2000? Of course no newspaper will tell you that, it spoils the scare story fantasies.

Another thing the newspapers don't report is the very poor record of the Japanese with nuclear power, they've long been notorious in the nuclear world for their numerous incidents in both research and production facilities. Of course reporting that localises a problem which the media would prefer to report as being a universally frightening one.

I could go on, but you'll get the drift from the above.
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[Blew it]

That nuclear power station would have survived undamaged had they learned a lesson from the 2004 Boxing day tsunami in Indonesia.

Most nuclear power stations are usually in coastal locations, little more than a few feet above sea level. Following the Boxing Day Tsumami, all nuclear stations should have been modified to protect the emergency diesel generators and associated switch-gear and pumps. Such plant should be either elevated to prevent inundation or, in sealed ground level chambers with high level snorkels for air intake and exhaust gas handling.

The owners of all nuclear power stations in that Tsunami prone area had seven years in which to protect the vital emergency cooling systems against inundation ....they did nothing!

 

[trex]

Tepco has plenty of contaminated water to get rid off and nowhere to store it.
What happens then? let contaminated water evaporate? let it leak into the ground? load it into a ship and dump it into deep waters? I think the problem will get worse - not better. If the core heats up, then they may just as well let it go the Chernobyl way and let the core sink into the ground and bury itself into its own lava.

 

[flecc]

Tepco has plenty of contaminated water to get rid off and nowhere to store it.
What happens then? let contaminated water evaporate? let it leak into the ground? load it into a ship and dump it into deep waters? I think the problem will get worse - not better. If the core heats up, then they may just as well let it go the Chernobyl way and let the core sink into the ground and bury itself into its own lava.

You haven't seemed to read what I posted above, the core will no more go the Chernobyl way or sink into the ground than the Three Mile Island ones that suffered the identical accident, total loss of cooling water. Both that PWR and the Fukushima BWR reactors share the same physics and behave identically. Three Mile Island was successfully cleared up, albeit with great difficulty, and so will be Fukushima.

As for the contaminated water, you've given the best answer. Ship it out to mid Pacific by tanker and run out it gradually as the ship makes way over the central zone. Over time in the vastness of the Pacific it will be impossible to measure any change in the natural radioactivity of the sea water. There's no need to even endanger a crew, long ago one of the major oil companies experimentally ran crewless remote control supertankers around the coasts of Africa with complete success. A trip straight out to mid-Pacific will be child's play in comparison.

But of course newspapers and those who believe them will not like these simple practical solutions or the facts, so will prefer to maintain the hysteria.

 

[flecc]

That nuclear power station would have survived undamaged had they learned a lesson from the 2004 Boxing day tsunami in Indonesia.

Most nuclear power stations are usually in coastal locations, little more than a few feet above sea level. Following the Boxing Day Tsumami, all nuclear stations should have been modified to protect the emergency diesel generators and associated switch-gear and pumps. Such plant should be either elevated to prevent inundation or, in sealed ground level chambers with high level snorkels for air intake and exhaust gas handling.

The owners of all nuclear power stations in that Tsunami prone area had seven years in which to protect the vital emergency cooling systems against inundation ....they did nothing!

Agreed Bob. However the silliest aspect of this whole affair was the positioning of this major station complex on the fault line side of the island. On the other side of that very large island no tsunami would be possible and the installation would be as safe as our coastal nuclear stations. This is just one example of the Japanese poor record with nuclear power that I commented on above.

 

[trex]

dumping in the middle of the Pacific is not possible, due to inernational treaty. Dumping into the sea of Japan is permitted. In the mean time. radioactive water containing Strontium 90 (28.79 yr half life - it goes straight to your bones) is leaking into the sea. Fishing will probably be banned all along the Eastern seaboard of Honshu island soon. There is no solution at present to stop water from the mountain aquifer getting into the sub soil of the damaged reactor.

 

[flecc]

dumping in the middle of the Pacific is not possible, due to inernational treaty. Dumping into the sea of Japan is permitted. In the mean time. radioactive water containing Strontium 90 (28.79 yr half life - it goes straight to your bones) is leaking into the sea. Fishing will probably be banned all along the Eastern seaboard of Honshu island soon. There is no solution at present to stop water from the mountain aquifer getting into the sub soil of the damaged reactor.

The strontium 90 level is 3 times the legal rate. That's far below the level of release we suffered from our Windscale accident in 1955 and even further below the releases from the USA's aerial testing of nuclear bombs in their southern deserts in the 1950s. Three times is peanuts, such are the huge safety margins in the permitted radiation levels from any source, which is why no-one is demonstrably being affected, past or present.

The gradual ocean release of contaminated water is perfectly practical, the probable fishing ban making it even more so. Slow intermittent releases taking advantage of the home waters current and tidal flows in the timing will ensure the pollution spread is maximised and shared by international waters. The point remains that the pollution of the vast volume of the Pacific and ultimately the whole of the world's oceans would be infinitesimal. Remember, all sea water is already radioactive at almost three times the level of fresh water due to the natural accumulation of 4.6 billion years. That measurement of level would be unchanged by the amounts from Fukushima.

Once again, why the panic and scaremongering? In 38 years time the Fukushima accident will be as forgotten by most of the world as Three Mile Island is now from 38 years ago. In that next 38 years there will be numerous disasters due to other causes taking tens of thousands of lives, and the lives lost by other methods of power generation will figure largely in those numbers. So once again, why the hysteria over an accident which has cost no lives and probably will cause none at all?

 

[trex]

the way Tepco manages Fukushima's decommissioning is going to influence public opinion about future electricity generation. Personally, I suspect oil companies have vested interest in failures of other sources of energy.

 

[flecc]

the way Tepco manages Fukushima's decommissioning is going to influence public opinion about future electricity generation. Personally, I suspect oil companies have vested interest in failures of other sources of energy.

Fully agree on that first point, the public take more note of danger messages than safety ones, and the Japanese record in this area is poor as I've commented before.

Oil companies involvement in other generation source accidents is impossible, it's just a well-worn conspiracy theory. Those 300 odd in ten years who fell to their deaths or were otherwise killed during wind power generation or construction could hardly be caused by big oil. The 800 plus killed when a dam collapsed during that same ten years again could not be due to that reason. And the average 80 men per week killed in Chinese coal mining for power generation again could hardly be due to oil company activity!

It's an inconvenient fact that nuclear power stations worldwide are the safest way to generate bulk electricity that's ever existed, simply because we are very aware of their potential danger and take so much more care with them.

Who would you prefer to travel with, a very capable driver in a high performance car or a poor driver in an average car?
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[Scimitar]

As for the contaminated water, you've given the best answer. Ship it out to mid Pacific by tanker and run out it gradually as the ship makes way over the central zone. Over time in the vastness of the Pacific it will be impossible to measure any change in the natural radioactivity of the sea water. There's no need to even endanger a crew, long ago one of the major oil companies experimentally ran crewless remote control supertankers around the coasts of Africa with complete success. A trip straight out to mid-Pacific will be child's play in comparison.

I can already hear the Greenies howling and chittering in the bushes.

 

[flecc]

I can already hear the Greenies howling and chittering in the bushes.

Good!
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