• If you are having problems logging in please use the Contact Us in the lower right hand corner of the forum page for assistance.

Western Australians more intelligent than Canada

Kathy

Well-known member
It makes more sense to create systems where-in we are able to capture emmissions from coal/gas including C02, mercury, radon etc... than to build more nuclear plants and pollute the world with more radiation.

Absolutely, nobody wants to deal with the unmangable, catastrophic problems associated with nuclear waste storage. England even dumped it in the Ocean for a while, until they got caught. Since there is no safe storage of nuclear waste, many countries have decided to use it to make weapons, armour plating for tanks, agriculture fertilizer (hot storage water).

The Western Australian government aims to keep its committment to the people and maintain their ban on uranium mining. I wish our Canadian government would ban it also; but, then the Queen wouldn't be able to make money from the sales of the uranium holdings she owns in Canada. Him, him.


WA rejects calls to end uranium mining ban.

January 8, 2007

The Western Australia Government has rejected a federal call to end its ban on uranium mining as a way of reducing greenhouse gas emissions.

Federal Environment Minister Ian Campbell said today that WA should reassess its ban because nuclear power could be used in the fight against climate change.

Senator Campbell said there were also huge benefits for the WA and Australian economies from mining uranium as the world was hungry for it.

But acting WA Premier Eric Ripper rejected the call to dump the ban, one of Labor's central policies in the 2005 state election, calling Senator Campbell "a nuclear fanatic".

"I mean, the answer to greenhouse gas emissions is to look at clean coal technology, to promote renewables, solar, wind, wave, biomass, to invest in energy efficiency," Mr Ripper said on ABC radio.

"And, of course, Western Australia is contributing substantially to one of the other answers, which is to export LNG so that it replaces coal, for example, in Chinese power stations."

Mr Ripper said if WA lifted the ban it would come under intense pressure to accept an international waste dump.

"And that's something I know our electorate would be strongly opposed to," he said.

"We went to the people at the last election saying we're opposed to nuclear power, we're opposed to uranium mining and we're opposed to a waste dump in Western Australia, that's the contract we have with the people and we intend to honour that commitment."
 

Kathy

Well-known member
Some acknowledgement that radiation damages the containers that they try to dispose of waste in. Their 1,400 year problem, is actually much worse, as there have already been substantial leaks at various storage locations including the Hanford site, which leaked radioactive waste into the Columbia River.

Published online: 10 January 2007; | doi:10.1038/news070108-6
Canned nuclear waste cooks its container
Estimates of radiation damage to materials have been too low.
Philip Ball
Storing high-level nuclear waste without any leakage over thousands of years may be harder than experts have thought, research published in Nature today shows.

Ian Farnan of Cambridge University, UK, and his co-workers have found that the radiation emitted from such waste could transform one candidate storage material into less durable glass after just 1,400 years — much more quickly than thought1.

Current plans for disposal of some of the most dangerous material generated in nuclear power plants, such as radioactive elements extracted from spent fuel rods, differ from one country to another. A common strategy being explored is to encase the waste in a hard, crystalline ceramic material — a kind of synthetic rock — and then put it in steel canisters and bury them in cavities excavated underground.

Because many radioactive substances continue emitting radiation for a very long time, the containment must persist for an awesome duration. Plutonium-239, one of the most deadly by-products of nuclear power, has a half-life of 24,000 years, meaning that only half of any initial batch has decayed over this time. Ideally it should stay put for about ten times as long: a quarter of a million years.

Candidate ceramic

Farnan and colleagues have investigated one candidate material hoped to do the job, called zircon (zirconium silicate). The plan is that this ceramic material will hold on fast to the radioactive atoms and stop them from finding their way into the environment — for example by being dissolved and dispersed in ground water.

The problem is that the radioactive waste damages the matrix that contains it. Many of the waste substances, including plutonium-239, emit alpha radiation, which travels for only very short distances (barely a few hundredths of a millimetre) in the ceramic, but creates havoc along the way.

A fast-moving alpha particle knocks into hundreds of atoms in its path, scattering them like skittles. Worse still, the radioactive atom from which the particle comes is sent hurtling in the other direction by the recoil. Even though its path is even shorter than that of an alpha particle, the atom is much heavier, and can knock thousands of atoms out of place in the ceramic.

All this disrupts the crystalline structure of the ceramic matrix, jumbling it up and turning it into a glass. That can make the material swell and become a less secure trap. Farnan says that some zircons that have been heavily damaged in this way by radiation have been found to dissolve hundreds of times faster than undamaged ones. So if the ceramic gets wet, there could be trouble.

Hit and run

Previous estimates of the radiation damage to waste-storage ceramics have relied largely on calculations and computer simulations. Now Farnan and colleagues have measured it directly.

They used a technique called nuclear magnetic resonance spectroscopy — similar to the method of magnetic resonance imaging (MRI) used in biomedicine — to measure the relative amounts of crystalline and glassy material, both in artificial zircon containing plutonium and in naturally occurring mineral zircon, which commonly contains radioactive uranium. They estimate that each alpha-decay event of a radioactive atom displaces around 5,000 atoms in the zircon - between 2.5 and 5 times more than predicted previously.

"There's more damage than we thought," says Rod Ewing, a specialist in nuclear-waste disposal at the University of Michigan in Ann Arbor.

There are other materials that may fare better than zircon, including other zirconium minerals. But Farnan's work implies that we probably don't yet fully understand how well any of these materials might stand up to the battering of radiation. He thinks the findings should encourage engineers to think very carefully about the matrix encasing the radioactive waste, rather than focusing on the geological characteristics of the burial site. Ideally, the best material would be able to heal itself, with the atoms displaced by alpha decay moving back slowly into their crystalline positions.

Ewing notes that the technique used in this study could be used to investigate these alternative materials, hopefully to find a longer-lived candidate.

Link: http://www.nature.com/news/2007/070108/full/070108-6.html
 
Top