http://www.physorg.com/news105208623.html
Garbage. Reprocessing spend fuel for energy use is going to be very helpful in turning the country away from fossil fuels. Perhaps these scientists should direct their concerns toward Iran.
Is anyone really surprised by this development? Since when has the US ever abided by the rules it judges other countries by? Look at the situation in Iraq... we went in on the pretext that they had 'weapons of mass distruction'... but we are the world's largest repository of such weapons. Basically, the US is hypocritical when it tells the rest of the world that they can't have WMDs while maintaining the world's largest arsenal. As for the contention that nuclear energy is clean; just how 'clean' is a fuel that leave a waste product that remains toxic for millions of years? If those folks who believe nuclear power is a clean power should be the ones to have the nuclear waste deposited in thier neighborhood. After they start having 'funny looking babies', perhaps they'll change thier tune. But, of course, these are the same folks who will cry outrage if such a disposal project is suggested. Nuclear power is flat out stupid!!! If you don't think so, then you live next to a reactor or a nuclear waste dump facility... But, you won't, will you?
So what I've been hearing is:
Don't use nuclear energy, it's not clean enough.
Don't use tidal current, it disturbs that habitat too much.
Don't use wind farms, they're a blight on the land scape.
You can't use solar power because it's not efficient enough.
But for the love of CHRIST get the HELL AWAY from fossil fuels.
Nuclear is safe, clean, and efficient. For those people who love the Europeans, take a look at France's electricity production & then look at Germany's. For once the French did something right.
I'll HAPPILY live next to a nuclear reactor. The schools are better, crime is lower, all around it makes the community better. Why? Because those who work there are MORE EDUCATED. Hence they get paid better and demand higher standards from the community and are more active in their communities.
You might want to look into how many nuclear accidents we've had in this country, and of those, how many people died because of them. (Hint: the answer's VERY VERY few)
Don't use nuclear energy, it's not clean enough.
Don't use tidal current, it disturbs that habitat too much.
Don't use wind farms, they're a blight on the land scape.
You can't use solar power because it's not efficient enough.
But for the love of CHRIST get the HELL AWAY from fossil fuels.
Nuclear is safe, clean, and efficient. For those people who love the Europeans, take a look at France's electricity production & then look at Germany's. For once the French did something right.
I'll HAPPILY live next to a nuclear reactor. The schools are better, crime is lower, all around it makes the community better. Why? Because those who work there are MORE EDUCATED. Hence they get paid better and demand higher standards from the community and are more active in their communities.
You might want to look into how many nuclear accidents we've had in this country, and of those, how many people died because of them. (Hint: the answer's VERY VERY few)
QUOTE (Argiod+Aug 2 2007, 05:09 AM)
As for the contention that nuclear energy is clean; just how 'clean' is a fuel that leave a waste product that remains toxic for millions of years? If those folks who believe nuclear power is a clean power should be the ones to have the nuclear waste deposited in thier neighborhood. After they start having 'funny looking babies', perhaps they'll change thier tune. But, of course, these are the same folks who will cry outrage if such a disposal project is suggested. Nuclear power is flat out stupid!!! If you don't think so, then you live next to a reactor or a nuclear waste dump facility... But, you won't, will you?
Actually, the LONGER nuclear waste is RADIOACTIVE, generally the LESS TOXIC it is.
A hunk of Uranium 235 would make a dandy paperweight for your desktop as it is REALLY dense (about twice that of lead) and with a half life of 4.5 billion years and its primary radiation being Alpha, which WON'T penetrate your skin, would be relatively harmless.
Now that Radon, with a half live of 4 days (or less), that's radioactive, and it seeps from virtually all granite bearing rocks in the world, since they contain Radium. Worse, since its a gas, you can inhale it and thus bring it into intimate contact with your lung tissue.
Nearly one in 15 homes in the U.S. has a high level of indoor Radon.
Have you had YOUR basement air checked?
Arthur
Actually, the LONGER nuclear waste is RADIOACTIVE, generally the LESS TOXIC it is.
A hunk of Uranium 235 would make a dandy paperweight for your desktop as it is REALLY dense (about twice that of lead) and with a half life of 4.5 billion years and its primary radiation being Alpha, which WON'T penetrate your skin, would be relatively harmless.
Now that Radon, with a half live of 4 days (or less), that's radioactive, and it seeps from virtually all granite bearing rocks in the world, since they contain Radium. Worse, since its a gas, you can inhale it and thus bring it into intimate contact with your lung tissue.
Nearly one in 15 homes in the U.S. has a high level of indoor Radon.
Have you had YOUR basement air checked?
Arthur
Ha ha Arthur. Funny.
Really, there is a very low probability of your home containing any dangerous levels of radon. Especially if you observe standard ASHRE guidlines for air changes, which you should anyway for a host of other reasons.
That is a true argument. US needs to stop thinking that international rules apply very strictly to everyone but them.
Really, there is a very low probability of your home containing any dangerous levels of radon. Especially if you observe standard ASHRE guidlines for air changes, which you should anyway for a host of other reasons.
QUOTE
the United States has a responsibility to "set the gold standard for safeguards and security" as an example for the rest of the world.
That is a true argument. US needs to stop thinking that international rules apply very strictly to everyone but them.
QUOTE (lengould+Aug 2 2007, 10:38 AM)
Ha ha Arthur. Funny.
Really, there is a very low probability of your home containing any dangerous levels of radon. Especially if you observe standard ASHRE guidlines for air changes, which you should anyway for a host of other reasons.
Well I agree, one SHOULD have decent air exchanges, but in attempts to cut down on energy losses people have also been weather sealing like crazy.
The EPA doesn't share your view on Radon.
Radon is a cancer-causing natural radioactive gas that you can’t see, smell or taste. Its presence in your home can pose a danger to your family's health. Radon is the leading cause of lung cancer among non-smokers. Radon is the second leading cause of lung cancer in America and claims about 20,000 lives annually. EPA has launched a new series of television, radio and print public service announcements encouraging people to test and fix their homes for radon. This is a good time to focus on testing and on fixing homes with a radon level of 4 pCi/L or more.
http://www.epa.gov/radon/
The EPA computes that if you have a home radon level of 4 pCi/L, and you have never smoked, then you have about the same risk of dying from radon induced lung cancer as from dying in a car crash. Its about 5 times worse if you smoke.
Arthur
Really, there is a very low probability of your home containing any dangerous levels of radon. Especially if you observe standard ASHRE guidlines for air changes, which you should anyway for a host of other reasons.
Well I agree, one SHOULD have decent air exchanges, but in attempts to cut down on energy losses people have also been weather sealing like crazy.
The EPA doesn't share your view on Radon.
Radon is a cancer-causing natural radioactive gas that you can’t see, smell or taste. Its presence in your home can pose a danger to your family's health. Radon is the leading cause of lung cancer among non-smokers. Radon is the second leading cause of lung cancer in America and claims about 20,000 lives annually. EPA has launched a new series of television, radio and print public service announcements encouraging people to test and fix their homes for radon. This is a good time to focus on testing and on fixing homes with a radon level of 4 pCi/L or more.
http://www.epa.gov/radon/
The EPA computes that if you have a home radon level of 4 pCi/L, and you have never smoked, then you have about the same risk of dying from radon induced lung cancer as from dying in a car crash. Its about 5 times worse if you smoke.
Arthur
QUOTE (adoucette+Aug 2 2007, 02:15 PM)
A hunk of Uranium 235 would make a dandy paperweight for your desktop as it is REALLY dense (about twice that of lead) and with a half life of 4.5 billion years and its primary radiation being Alpha, which WON'T penetrate your skin, would be relatively harmless.
I believe you are thinking about Uranium 238 here. Uranium 235 has a half life of 700 million years. A "chunk" on your desk, besides emitting alpha particles would be seriously blasting your body with neutrons.
I do have a DU ordnance paperweight, but even that is coated with Tungsten.
Oops.
I really don't think you would be overly concerned from radiation though, as long as the mass of U235 was like a normal paperweight though.
U235 is ~ 7 times as radioactive as U238, but still its primary decay products are alpha and some beta, neither of which are harmful at a distance of 1 foot. While there would be more Gamma radiation from U235, most of that is quite weak and would be absorbed by the Uranium itself, possibly making your U235 paper weight just slightly warmer than room temp. Counter intuitively, the reason U235 is fissionable is because the neutrons released are relatively slow moving.
The alpha radiation of the 8 alpha emitting nuclides contained in the U-238 series presents a radiation hazard only on ingestion or inhalation of uranium dust. So to be safe, paint your Uranium paperweight. The beta radiation from the 6 beta emitting nuclides in the U-238 series present a VERY MINOR external radiation hazard, but only if you are actually holding the paper weight.
Arthur
I really don't think you would be overly concerned from radiation though, as long as the mass of U235 was like a normal paperweight though.
U235 is ~ 7 times as radioactive as U238, but still its primary decay products are alpha and some beta, neither of which are harmful at a distance of 1 foot. While there would be more Gamma radiation from U235, most of that is quite weak and would be absorbed by the Uranium itself, possibly making your U235 paper weight just slightly warmer than room temp. Counter intuitively, the reason U235 is fissionable is because the neutrons released are relatively slow moving.
The alpha radiation of the 8 alpha emitting nuclides contained in the U-238 series presents a radiation hazard only on ingestion or inhalation of uranium dust. So to be safe, paint your Uranium paperweight. The beta radiation from the 6 beta emitting nuclides in the U-238 series present a VERY MINOR external radiation hazard, but only if you are actually holding the paper weight.
Arthur
QUOTE (adoucette+Aug 3 2007, 01:49 PM)
Oops.
So to be safe, paint your Uranium paperweight. The beta radiation from the 6 beta emitting nuclides in the U-238 series present a VERY MINOR external radiation hazard, but only if you are actually holding the paper weight.
Arthur
Too make it cool
paint it with Cadmium Sulphide so it glows in the dark.
So to be safe, paint your Uranium paperweight. The beta radiation from the 6 beta emitting nuclides in the U-238 series present a VERY MINOR external radiation hazard, but only if you are actually holding the paper weight.
Arthur
Too make it cool
paint it with Cadmium Sulphide so it glows in the dark.
Thanks to the IAEA, I feel so much safer now. 
When you are talking about a paper weight of uranium? Are you talking about Natural uranium as found in nature or about "Highly Enriched Uranium" weapon grade that consists of 90 % uranium-235. You know of course that some research reactors and all U.S. naval reactors use 'HEU'. Normal power plants typically use 3 to 5 percent uranium-235 in the States. Can you point me to those links where you reached that conclusion from? I think, if i remember right, that the Hiroshima bomb was something in the size of half a kg. Hmm, i better correct that ' It contained 64 kg of uranium, of which 0.7 kg underwent nuclear fission' that was what i was referring to, that 0.7 kg.
I find it quite tasteless to joke about, even if it would be proved correct.
"The mining of uranium is also a dangerous business. Miners are exposed to the hazards of ionizing radiation from radon and radioactive dust. The environment of the mine and surrounds is destroyed. The local communities, often indigenous people, the waterways and whole ecosystems are under threat of, and often are contaminated by radioactive materials. People suffer cancer and birth defects. Other living organisms also suffer these and other fates.
Tailings dams are where all the unwanted material that is mined is stored. Once the mining stops, the tailing dams are left to become hills of fine sand like solids. This retains 80% of the radioactivity of the uranium ore body. Some of this waste material can decay into a gas (radon-222) which can spread over the region. Radioactive radium, dust and radon contaminate surrounding ecosystems. Natural disasters, such as earthquakes or flash floods are often not considered when the dams are designed, posing additional threats. The radioactive dangers persist for over 100 000 years from these uranium mining tailings dams."
"Uranium and associated decay products thorium-230 and radium-226 will remain hazardous for thousands of years. Current U.S. regulations, however, cover a period of 1,000 years for mill tailings and at most 500 years for "low-level" radioactive waste. This means that future generations--far beyond those promised protection by these regulations--will likely face significant risks from uranium mining, milling, and processing activities."
Perhaps this to belong here :)
" Repository Performance
An immobilization form is judged acceptable for disposal in a federal geologic repository according to a fitness-for-purpose criterion that includes regulatory, licensing, and long-term performance factors. The main long-term, post-emplacement performance considerations are criticality safety and the potential of the form to contaminate the biosphere. In the U.S., the regulatory performance period for high-level waste and spent fuel in a geologic repository has been specified as 10,000 years. (The pertinent regulations are currently under review and may change.) However, the emplaced plutonium and its uranium-235 decay product remain fissile over much longer periods (hundreds of thousands of years for plutonium and billions of years for uranium-235), over which criticality safety may need to be assured.
Scenarios for criticality events can be divided into three categories of criticality safety: safety of the essentially undisturbed emplacement waste package, safety of disrupted waste packages, and safety of disposed fissile materials released from the disposal form followed by possible transport within the repository or in the geosphere.
In general, the criticality safety of the first category of scenarios can be assured with very high confidence, but assuring the safety of the latter two categories is more difficult and will depend on such factors as the fissile material content of the disposal form, canisters, and waste package; the geometry of the disrupted configuration; and the degree of degradation of the disposal form and its interactions with surrounding rock and water.
Notwithstanding the complexity of the problem, key properties of disposal forms that affect criticality safety have been identified. They are fissile loading of disposal forms, concentration of the neutron absorber, and neutron absorption properties of the immobilization matrix. Other factors are resistance of disposal form constituents to release and transport by groundwater and the rates and relative timing of releases of different components.
Characteristics of elemental release from disposal forms may be very different for different disposal forms (especially glass and ceramic) and are affected by compositions of water and disposal form, solubility of the constituents, active surface areas available for reaction with water, compositional and thermal stability of disposal forms, physical and chemical homogeneity of disposal forms, and radiation effects (damage in disposal form and radiolysis in water). Researchers are particularly concerned about the susceptibility of the disposal form to cracking during fabrication and after emplacement and to the development of permeable channels within the disposal form caused by preferential dissolution of certain phases or along grain boundaries. "
And i do agree on that they (US) should prove their relative safety by allowing it to be inspected by the IAEA. Any other act can only be seen as sheer arrogance in the face of the world community. Then i would suggest the US to withdraw from the UN too, and start to act unilaterally, ahhh :) but they already does, don't they :)
I find it quite tasteless to joke about, even if it would be proved correct.
"The mining of uranium is also a dangerous business. Miners are exposed to the hazards of ionizing radiation from radon and radioactive dust. The environment of the mine and surrounds is destroyed. The local communities, often indigenous people, the waterways and whole ecosystems are under threat of, and often are contaminated by radioactive materials. People suffer cancer and birth defects. Other living organisms also suffer these and other fates.
Tailings dams are where all the unwanted material that is mined is stored. Once the mining stops, the tailing dams are left to become hills of fine sand like solids. This retains 80% of the radioactivity of the uranium ore body. Some of this waste material can decay into a gas (radon-222) which can spread over the region. Radioactive radium, dust and radon contaminate surrounding ecosystems. Natural disasters, such as earthquakes or flash floods are often not considered when the dams are designed, posing additional threats. The radioactive dangers persist for over 100 000 years from these uranium mining tailings dams."
"Uranium and associated decay products thorium-230 and radium-226 will remain hazardous for thousands of years. Current U.S. regulations, however, cover a period of 1,000 years for mill tailings and at most 500 years for "low-level" radioactive waste. This means that future generations--far beyond those promised protection by these regulations--will likely face significant risks from uranium mining, milling, and processing activities."
Perhaps this to belong here :)
" Repository Performance
An immobilization form is judged acceptable for disposal in a federal geologic repository according to a fitness-for-purpose criterion that includes regulatory, licensing, and long-term performance factors. The main long-term, post-emplacement performance considerations are criticality safety and the potential of the form to contaminate the biosphere. In the U.S., the regulatory performance period for high-level waste and spent fuel in a geologic repository has been specified as 10,000 years. (The pertinent regulations are currently under review and may change.) However, the emplaced plutonium and its uranium-235 decay product remain fissile over much longer periods (hundreds of thousands of years for plutonium and billions of years for uranium-235), over which criticality safety may need to be assured.
Scenarios for criticality events can be divided into three categories of criticality safety: safety of the essentially undisturbed emplacement waste package, safety of disrupted waste packages, and safety of disposed fissile materials released from the disposal form followed by possible transport within the repository or in the geosphere.
In general, the criticality safety of the first category of scenarios can be assured with very high confidence, but assuring the safety of the latter two categories is more difficult and will depend on such factors as the fissile material content of the disposal form, canisters, and waste package; the geometry of the disrupted configuration; and the degree of degradation of the disposal form and its interactions with surrounding rock and water.
Notwithstanding the complexity of the problem, key properties of disposal forms that affect criticality safety have been identified. They are fissile loading of disposal forms, concentration of the neutron absorber, and neutron absorption properties of the immobilization matrix. Other factors are resistance of disposal form constituents to release and transport by groundwater and the rates and relative timing of releases of different components.
Characteristics of elemental release from disposal forms may be very different for different disposal forms (especially glass and ceramic) and are affected by compositions of water and disposal form, solubility of the constituents, active surface areas available for reaction with water, compositional and thermal stability of disposal forms, physical and chemical homogeneity of disposal forms, and radiation effects (damage in disposal form and radiolysis in water). Researchers are particularly concerned about the susceptibility of the disposal form to cracking during fabrication and after emplacement and to the development of permeable channels within the disposal form caused by preferential dissolution of certain phases or along grain boundaries. "
And i do agree on that they (US) should prove their relative safety by allowing it to be inspected by the IAEA. Any other act can only be seen as sheer arrogance in the face of the world community. Then i would suggest the US to withdraw from the UN too, and start to act unilaterally, ahhh :) but they already does, don't they :)
QUOTE (yor_on+Sep 22 2007, 06:02 PM)
When you are talking about a paper weight of uranium? Are you talking about Natural uranium as found in nature or about "Highly Enriched Uranium" weapon grade that consists of 90 % uranium-235. You know of course that some research reactors and all U.S. naval reactors use 'HEU'. Normal power plants typically use 3 to 5 percent uranium-235 in the States. Can you point me to those links where you reached that conclusion from? I think, if i remember right, that the Hiroshima bomb was something in the size of half a kg. Hmm, i better correct that ' It contained 64 kg of uranium, of which 0.7 kg underwent nuclear fission' that was what i was referring to, that 0.7 kg.
I find it quite tasteless to joke about, even if it would be proved correct.
I was talking about Natural Uranium, but it wouldn't be that much different.
Enriched Uranium is still not a very radioactive material with a half life of over 700 million years.
And, no, it wasn't a joke and had nothing to do with enriched Uraniums use in atomic bombs.
Its about PHYSICS.
The fact that Uranium 235 can become a critical mass, setting off a chain reaction of fissioning Uranium atoms resulting in a nuclear explosion has nothing to do with its level of radiation danger when in subcritical quantities.
A common misconception is because Uranium is used in reactors and bombs is it must be highly radioactive, but such is NOT the case. Uranium is WEAKLY radioactive.
Which is a GOOD thing since its part of virtually ALL the rocks, soil and water on the planet.
The reason Uranium 238 is not particularly radioactive is because of its incredibly long half life of 4.5 BILLION years. The second reason it is not particularly dangerous is its radioactive decay primarily release alpha radiation (which won't penetrate your skin) and which only presents a radiation hazard when ingested or when you inhale uranium dust. Which is why I said that to be safe you should paint your Uranium paperweight.
Even when ingested the fact is, Uranium is much more TOXIC because of its chemical properties (does in your kidneys) than from radiologic issues.
According to Wiki:
Arthur
I find it quite tasteless to joke about, even if it would be proved correct.
I was talking about Natural Uranium, but it wouldn't be that much different.
Enriched Uranium is still not a very radioactive material with a half life of over 700 million years.
And, no, it wasn't a joke and had nothing to do with enriched Uraniums use in atomic bombs.
Its about PHYSICS.
The fact that Uranium 235 can become a critical mass, setting off a chain reaction of fissioning Uranium atoms resulting in a nuclear explosion has nothing to do with its level of radiation danger when in subcritical quantities.
A common misconception is because Uranium is used in reactors and bombs is it must be highly radioactive, but such is NOT the case. Uranium is WEAKLY radioactive.
Which is a GOOD thing since its part of virtually ALL the rocks, soil and water on the planet.
The reason Uranium 238 is not particularly radioactive is because of its incredibly long half life of 4.5 BILLION years. The second reason it is not particularly dangerous is its radioactive decay primarily release alpha radiation (which won't penetrate your skin) and which only presents a radiation hazard when ingested or when you inhale uranium dust. Which is why I said that to be safe you should paint your Uranium paperweight.
Even when ingested the fact is, Uranium is much more TOXIC because of its chemical properties (does in your kidneys) than from radiologic issues.
According to Wiki:
QUOTE
The greatest health risk from large intakes of uranium is toxic damage to the kidneys, because, in addition to being weakly radioactive, uranium is a toxic metal. Radiological effects are generally local because this is the nature of alpha radiation, the primary form from U-238 decay. No human cancer has been seen as a result of exposure to natural or depleted uranium,
Arthur
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