14 replies to this topic

[stocks]

Going bananas over radiation

With all the worries over radiation leaks from Japan, and hoarding of potassium iodide tablets, many people might be surprised to learn that they will get more radiation from eating a single banana today than they will from Japan’s nuclear reactor problems.

Read more: http://dailycaller.c.../#ixzz1GywD0NZw

Doctor's orders: take a pill before eating a banana:

Surgeon general clarifies position on potassium iodide as protection against nuclear radiation

"We can't be over-prepared -- we learned that with 9/11, we learned that with Katrina and we learned that this week with the tsunami," she said. "Even if it's one life we save by being prepared, it's worth it."

General

[stocks]

Scientific American -> Coal Ash Is More Radioactive than Nuclear Waste

By burning away all the pesky carbon and other impurities, coal power plants produce heaps of radiation

Ash

A power plant has overexposed its workers to radiation, and the Nuclear Regulatory Commission is proposing a fine. The plant, though, is not a reactor; it runs on coal.

Coal

Some analysts suggest that coal-fired power plants expose nearby residents to higher radiation doses than nuclear plants meeting U. S. government regulations.

Among the other trace elements listed in Table 3, coal contains between <1 and 10 parts per million (ppm) of uranium, and between <2.5 and 25 ppm of thorium, as well as radioactive potassium-40.

Coal

[Rogerdodger]

It seems like the greatest danger here is slipping on a banana peel.

Is that a Banana in Your Pocket or Are You Radioactive?
March 18, 2011
If the banana is eaten, the dose equivalent is about 0.01 mrem. 0.01 mrem is equivalent to 0.1 μSv.
A radiation dose equivalent of 100 μSv (10 mrem, or 1,000 BED) increases an average adult human's risk of death by about one micromort – the same risk as eating 40 tablespoons of peanut butter, or of smoking 1.4 cigarettes.
Yesterday's spike at the Fukushima Dai-chi plant was 400 mSv per hour.

PS: "Over 2,000 nuclear explosions have been conducted, in over a dozen different sites around the world."
"The U.S. Navy has accumulated over 5,400 "reactor years" of accident-free experience, and operates more than 80 nuclear-powered ships."

Edited by Rogerdodger, 18 March 2011 - 10:58 PM.

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Some of these radiation detectors have amazing sensitivity:

One of the DOE monitors in Sacramento, Calif., detected tiny quantities of a radioisotope (xenon-133). The level of the isotope detected would result in one-millionth of the dose rate that a person would normally receive from natural background sources.

Rad

[stocks]

On prediction of “worst case” scenarios

MIT NSE Nuclear Information

At Three Mile Island, approximately 50% of the core’s nuclear fuel melted, and just 5/8 inch (out of 9 inches) of the reactor pressure vessel’s internal surface was ablated. During the corium’s contact with the bottom of the vessel, the vessel glowed red-hot for about an hour. The heat to which the vessel was exposed induced metallurgical changes in the steel, rendering it more brittle. Instrumentation penetrations in the lower vessel head also suffered damage. Nevertheless, the molten core was contained by the vessel.

In the event that molten corium does, as has been the case in some experiments, penetrate the lower head of the reactor vessel, it will drop onto the concrete basemat of the containment and spread out as far as possible. The interaction of corium with concrete is known to produce a buildup of non-condensable gases within the containment, a process called molten-core concrete interaction (MCCI).

experiments have shown that without water quenching, corium under conditions similar to those present at Fukushima Dai-ichi will ablate the meters-thick concrete pad at a rate of just millimeters per minute. Gases would build up within the containment at a rate which would require filtered ventilation of the containment in order to prevent rupture.

If, however, water is supplied to quench the corium as it spreads onto the reactor floor, the ablation occurs at 5-7% of the pre-quench rate, and production of gases is suppressed. The rate of ablation continues to undergo fits and starts, as the corium forms a solid crust, and then this crust is broken and re-formed.

Worst

[stocks]

Japan: whatever happened to the nuclear meltdown?

As one who earns his living in the media these days, I can only apologise on behalf of my profession for the unbelievable levels of fear and misinformation purveyed this week. I have never been so ashamed to call myself a journalist.

The lesson to learn here is that if your country is hit by a monster earthquake and tsunami, one of the safest places to be is at the local nuclear powerplant. Other Japanese nuclear powerplants in the quake-stricken area, in fact, are sheltering homeless refugees in their buildings – which are some of the few in the region left standing at all, let alone with heating, water and other amenities.

Nothing else in the quake-stricken area has come through anything like as well as the nuclear power stations, or with so little harm to the population. All other forms of infrastructure – transport, housing, industries – have failed the people in and around them comprehensively, leading to deaths most probably in the tens of thousands. ...
And yet nobody will say after this: “don’t build roads; don’t build towns; don’t build ships or chemical plants or oil refineries or railways”

Nuke

[stocks]

Pass the Plutonium

People think that Fukushima will mean the end of nuclear power, but I'm convinced it's the opposite. We're going to lose our nuclear virginity over this accident and start seeing the world as adults

For years we've lived with the impression that a nuclear meltdown is the equivalent of a nuclear bomb going off, killing thousands and leaving whole landscapes uninhabitable. Now we've had one and look what's happened. The fourth worst earthquake in history has failed to crack open the concrete containment and the difficulty arose only because the utility didn't have enough backup electricity on hand. Fukushima remains a horribly dangerous situation and the workers who are bringing the reactor under control ought to be given a parade down Broadway when it's finally over. But what has the toll been so far? One worker died in a steam explosion and others have been exposed to levels of radiation that may increase their chances of getting cancer somewhere down the line. But this is basically an industrial accident. As Monbiot points out, coal mining in China kills more people in a week than ever died as a result of Chernobyl.

One by one, the nuclear myths have fallen. In the immediate aftermath, reporters and commentators right up to Bill O'Reilly were anticipating a dreaded "meltdown" would be the equivalent of a nuclear bomb. In fact, a meltdown simply means the fuel has melted to the bottom of the steel pressure vessel, which is inside the concrete containment structure. In days of yore environmentalists dreamed up "The China Syndrome," which had the fuel melting through the pressure vessel, then through the concrete containment and continuing on its way to China until it hit groundwater, at which point it would cause a steam explosion that would kill everybody in Los Angeles -- or at least that's what Jane Fonda was told. Three Mile Island proved this wouldn't happen. Fukushima has confirmed it.

In the effort to portray nuclear power as the devil's handiwork, Ralph Nader once labeled plutonium "the most toxic substance ever known to mankind." In fact it is about as toxic as caffeine. Bernard Cohen, the tireless crusader for nuclear common sense, offered many times to eat as much plutonium as Nader would eat caffeine on "The Tonight Show" but Nader never took him up.

Nuke

[stocks]

Comments on the radiation levels resulting from the damaged nuclear power plants
in Fukushima and the impact of these levels on human health.

Jacquelyn, C. Yanch Ph.D. MIT
4 April 2011

Overview:
The radiation doses and dose-rates experienced by residents of Japan, particularly those in
Fukushima prefecture, are examined and the expected impact of these elevated radiation
conditions on human health is discussed. Overall, doses are very low and the impact on health, if
any, is expected to be minimal for reasons outlined within.

A similar examination is performed for the most heavily exposed workers at the Daiichi
nuclear power plant. Elevated risks of a fatal cancer that might be diagnosed years or decades in
the future are calculated using standard risk models utilized in occupational radiation protection.

Summary:
• There is no evidence demonstrating that the dose-rates measured in Iitate Village or the
cumulated dose (to date) of 7600 microSievert results in harm. [Doses to other areas of
Japan are substantially lower than those measured in Iitate Village in Fukushima
prefecture.]
• The cumulative dose of 7600 microSievert is similar to that received from a CT scan of
the chest and substantially less than that received from a CT scan of the abdomen.
• Doses have been spread out in time, a situation that results in substantially less biological
impact than the same dose delivered acutely.
• Doses to a small number of radiation workers at the damaged nuclear power plant are
substantially higher than doses to the public. Applying standard risk models used in
radiation protection predicts increased fatal cancer risk of 1.7-3.9% for these radiation
workers.

MIT

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Why nuclear power is still a good choice

The irony of Fukushima is that in forcing us all to confront our deepest fears about the dangers of nuclear power, we find many of them to be wildly irrational — based on scare stories propagated through years of unchallenged mythology and the repeated exaggerations of self-proclaimed "experts" in the anti-nuclear movement

The science on radiation tells us that the effects of Fukushima are serious but so far much less so than some of the more hyperbolic media coverage might suggest. The power plant operator, Tokyo Electric Power Co., has been releasing enormous quantities of radioactive water into the sea, for example. It sounds scary, but a member of the public would have to eat seaweed and seafood harvested just one mile from the discharge pipe for a year to receive an effective dose of 0.6 millisieverts. To put this in context, every American receives on average 3 millisieverts each year from natural background radiation, and a hundred times more than this in some naturally radioactive areas. As for the Tokyo tap water that was declared unsafe for babies, the highest measured levels of radioactivity were 210 becquerels per liter, less than a quarter of the European legal limit of 1,000 becquerels per liter. Those leaving Tokyo because of this threat will have received more radiation on the airplane flight out than if they had been more rational and stayed put.

Nuclear energy is not entirely safe, as Fukushima clearly shows, even if the current radiation-related death toll is zero and will likely remain so

LA Times

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Nuclear energy is not entirely safe, as Fukushima clearly shows, even if the current radiation-related death toll is zero and will likely remain so

Banqiao Dam

The Banqiao Reservoir Dam is a dam on the River Ru in Zhumadian Prefecture, Henan province, China. It infamously failed in 1975, causing more casualties than any other dam failure in history, and was subsequently rebuilt.

The Banqiao dam and Shimantan Reservoir Dam are among 62 dams in Zhumadian Prefecture of China's Henan Province that failed catastrophically or were intentionally destroyed in 1975 during Typhoon Nina.
The dam failure killed an estimated 171,000 people; 11 million people lost their homes. It also caused the sudden loss of 18 GW of power, the equivalent of roughly 9 very large modern coal fired power stations or about 20 nuclear reactors, equalling about 1/3 the peak demand on the UK National Grid.

Banqiao