... I know much more about forestry practices in temperate climates, especially in our own USA forests. We have heavy machinery which can cut selected trees from stands in mature forests and leave others intact. That way we can selectively remove trees for use now and preserve the forest for harvest next year....and so on. Additionally, new trees are replanted to grow and replace the ones we've used. Wood is a renewable resource, and it's pretty easy to do with today's methods. ...
One of the biggest things that I have seen upon moving to Maine, has been the 'tree growth' laws here.
When we lived in Washington, it was 'The Law' that when you cut timber it mus tall be re-planted within two years. But not so here in Maine. I now own a wood-lot, and in getting a 'Forestry Management Plan' from a state forester to keep it in timber growth, I learned that such is not required here. Also the local officials would very much fight you at any mention of the idea of re-planting timber trees.
The local thought is to allow nature to decide if nature wants trees growing on the land.
So instead of 'wood-lot' properties that are all timber in various stages of growth, much of it is: open fields, and brush and softwood/hardwood mixes of no commercial value.
The only thing the sate really seems to allow, is spraying broad-leaf herbicides to limit tree growth by species. The forester that I bought my land from, sprays herbicides by crop-duster to do this. He sprays many square miles with herbicides to kill everything but conifers, every summer.
We moved here thinking that we would be re-planting a few acres each year, but only if we want to buy nursery trees out-of-state and smuggle them in.
If the current age of the Earth is about five billion years, then 600,000 years of data, if we really have it, represents about a tenth of one percent of our planet's climatologic history. Try to predict exactly what will happen in your life over the next year from what happens to you in the next nine hours--one-tenth of one percent of a year.
There are things that we do know and can prove. Things like that the Sun is a slightly variable star--its energy output fluctuates a bit. Its variations are mostly irregular--no one can predict if it will put out more or less energy on Saturday as it did today. Natural disasters like volcanoes and prairie/forest fires happen suddenly, and can dump far more pollution into the atmosphere in a short period of time than any man made source short of a nuclear bomb. Factories are much cleaner today than they were 100 years ago. There are more trees in America today than there were in the 1700s. In short, if the guesses are correct and the Earth really is getting permanently warmer, human pollution is only a minor factor in it, if at all.
Researchers link wildfires, climate change By CHARLES J. HANLEY, AP Special Correspondent
Scientists worldwide are watching temperatures rise, the land turn dry and vast forests go up in flames.
In the Siberian taiga and Canadian Rockies, in southern California and Australia, researchers find growing evidence tying an upsurge in wildfires to climate change, an impact long predicted by global-warming forecasters.
A team at California's Scripps Institution, in a headline-making report this month, found that warmer temperatures, causing earlier snow runoff and consequently drier summer conditions, were the key factor in an explosion of big wildfires in the U.S. West over three decades, including fires now rampaging east of Los Angeles.
Researchers previously reached similar conclusions in Canada, where fire is destroying an average 6.4 million acres a year, compared with 2.5 million in the early 1970s. And an upcoming U.S.-Russian-Canadian scientific paper points to links between warming and wildfires in Siberia, where 2006 already qualifies as an extreme fire season, sixth in the past eight years. Far to the south in drought-stricken Australia, meanwhile, 2005 was the hottest year on record, and the dangerous bushfire season is growing longer.
"Temperature increases are intimately linked with increases in area burned in Canada, and I would expect the same worldwide," said Mike Flannigan, a veteran Canadian Forest Service researcher.
Nadezda M. Tchebakova, a climatologist at Russia's Sukachev Institute of Forestry, said southern Siberia's average winter temperatures in the 1980-2000 period were 2 to 4 degrees Celsius (3.6 to 7.2 degrees Fahrenheit) warmer than the pre-1960 norm.
"Snowmelt starts much earlier in the spring," she said by telephone from the Siberian city of Krasnoyarsk. "Precipitation is decreasing. This combination of elevated temperatures and decreased precipitation should provide conditions for greater fire occurrence."
As she spoke, newly ignited blazes raced through the conifer forests of Evenkiya, a summer fishing and hunting region north of Krasnoyarsk.
The Sukachev institute's satellite data show that more than 29 million acres — an area the size of Pennsylvania — have been burned in Russia already this year. Orbiting cameras see a red-and-green checkerboard in Siberia, of "hotspots" among endless evergreens.
The Intergovernmental Panel on Climate Change, an authoritative U.N.-sponsored network of scientists, has long predicted that summer drying and droughts would worsen forest fires, which in many regions are primarily set by humans.
Global temperatures rose an average 1 degree Fahrenheit in the 20th century, and warming will continue as long as manmade "greenhouse gases," mostly carbon dioxide from fossil-fuel burning, accumulate in the atmosphere, the panel says.
"The change is much more rapid than initially forecast 10 or 15 years ago," Brian Stocks, a retired Canadian Forest Service scientist, said of the fires. "It seems people are finally beginning to take a look at it."
The Scripps study, in the journal Science, was unique in collating detailed data from 34 years of U.S. western wildfires with temperature, snowmelt and streamflow records. Wildfire frequency varies widely from year to year, but the California researchers found a clear trend: The average number of large fires almost quadrupled between the first and second halves of that period.
They also looked at land-use changes and forest management practices, but concluded they were secondary factors in the upsurge of fires. There were "many more wildfires burning in hotter than in cooler years," they reported.
Such detailed data don't exist on a global scale. Doing a similar study in Russia would be difficult because Soviet-era records are unreliable. And specialists caution that wildfires remain complex phenomena. In many regions, slash-and-burn farmers, arsonists and others start most fires, and fire professionals say modifying human behavior is key.
But although humans are the prime cause, "coupled with climate change, things are becoming worse," said Johann Goldammer, director of the Global Fire Monitoring Center at Germany's Freiburg University.
A nonhuman cause, meanwhile, may be on the rise. Warming in high northern latitudes is expected to generate more lightning, igniting more forest fires, notes the report by Amber J. Soja of the U.S. National Institute of Aerospace, Tchebakova and other U.S., Russian and Canadian scientists.
Their paper, upcoming in the U.S. journal Global and Planetary Change, looks at how current reality compares with still other effects of climate change previously foreseen for northern, boreal regions — Siberia, Canada, Alaska.
"The forest in Siberia is shifting northward, and the forest-steppe (mixed forest and plain) is replacing it in the south," Tchebakova said. "Those were the predictions."
In Alaska, the international team found a decline in growth of white spruce trees and a spread of forest insect infestation — also both predicted in computerized climate-change scenarios.
Goldammer pointed out that boreal forests may be crucially linked to the fate of the global environment, since the forests and their peat soils hold about one-third of Earth's stored carbon.
Forest and peat fires release carbon dioxide into the atmosphere, adding to climate warming, which in turn will intensify forest fires, further worsening warming in a planetary feedback loop.
"This is a carbon bomb," Goldammer said of the northern forest. "It's sitting there waiting to be ignited, and there is already ignition going on."
like i said...multiplied, amplified, and exploding in our face
Todd - that was an impressive list of references in the first post above. I've only checked out the last one so far, but it seems it's carefully thought out and meets genuine scientific protocol. Thanks for that. There's many thins there I haven't come across yet.
With respect to Zixar's comments, I understand his position and I agree that politicians like to use this issue as a club to move us in a particular direction, and that does suck.
However, the things I'm looking at don't restrict themselves to the USA alone. I'm looking globally. As far as the planet is concerned, it doesn't matter which country or continent pumps the CO2 into the atmosphere - or if it's coming from forest fires or volcanos...it's just being seriously over-loaded.
Galen - I don't understand Maine's position on additional planting unless it is protecting it's own lumber interests and/or overall land management plan. It is interesting they they encourage conifers by removing deciduous trees. Nature does seem to allow both to grow at those latitudes in general, although the northernmost parts of Maine may be more suited to boreal forests.
It is true, BTW, that the total CO2 released from dead stands is the same whether it's done by burning or the action of decay organisms. The difference is in the rate of CO2 release. When decay organisms do it, the release is about the same as the uptake by living trees, so the net increase is zero.
The way this planet works amazes me all the time. All of the standing vegetation, and animal populations are made of carbon compounds and the source of this carbon is ultimately CO2 from the atmosphere. When speaking about CO2 as a greenhouse gas, we think in terms of thousands of pounds/year or more. Yet, in the real scheme of things, the average % of CO2 in the air hovers around a bit less than 0.5% - - one half of one percent of the total atmosphere by volume (at sea level, of course). Of course this has accumulated over many millions of years, however it is still an impressive accomplishment for the process of photosyntheses - - which has been calculated by bio-physicists to be around 33% efficient! These things make me scratch my head and go WOW! That impresses me.
Galen - I don't understand Maine's position on additional planting unless it is protecting it's own lumber interests and/or overall land management plan. It is interesting they they encourage conifers by removing deciduous trees. Nature does seem to allow both to grow at those latitudes in general, although the northernmost parts of Maine may be more suited to boreal forests. ...
Lumber mills are shutting down. Not enough timber.
We do have lots of college educated 'foresters' who charge to consult, and to own a 'tree-lot' you have to pay a forester every ten years to make a 'management plan' for your property. Pay extra and instead of handing you one from a big stack they had printed, they will actually print it off their computer with your name on the front page.
So the forestry industry seems to have a lot of folks in it, just fewer and fewer loggers, timber-mills, logging trucks, and paper mills, and chip mills.
:)
The 'modern forest industry' is more college graduate, college research studys and state forester oriented. They are phasing out the folks who actually touch trees and wood.
Our local papermill just closed a couple months ago. They accounted for just over a 1/3 of the local town's tax budget. [Well not in MY town, but the next town over, they are a bigger town, they have a post office and a gas station. My town is much smaller. But we do share their zip code.]
I dont know. it seems to me, that with so much empty forest land. If they would jsut require replanting, then every 20 years or so each plot could be timbered again, and it would keep the industry going.
Instead they aim at being able to re-timber in 80 years, from the previous cutting. Which seems to me is really stupid. But I am not a native Mainiac, so I just dont get it.
It is pretty, and rural and has lots of hunting and fishing. :)
We are way off-topic here, sorry folks!
I did not want anyone to think that re-planting was being done everywhere in all of U.S. forests.
I'm sorry, it's just really hard for me to take anything seriously that has Gore's name attached to it. dry.gif
I'm with you, Belle, Gore has the personality of a fence post and might be smarter than the average high school graduate, but imho, if it was 3pm and he said it was 3 o'clock, I'd still call time service.
I think of him and a lot of people like him as though they were "town cryers". Shouting at the rain because they think it will get them all wet. (It won't if they get out of it).
The only things that are truly economical to recycle are aluminum and plastics. Recycling paper generates more toxic waste than harvesting new trees. The paper companies know this. They are also the biggest tree farmers on the planet, because paper is literally a cash crop for them. It doesn't matter much if the tree is "old growth" or "new growth", they all scrub CO2 from the atmosphere.
I guess my biggest question would be your definition of "economical". I know that scrap steel is so valuable that China's demand for it has pushed up the price of finished steel dramatically. And the price of both lumber and concrete with it.
The price paid for scrap copper and brass just jumped off the charts, alledgedly because of the China demand to build their infrastructure.
I watch containers loaded with steel, AL and electronics scrap heading for China and India every week at the local scrap/recycling yard.
If, by economical, you mean that it would be recycled in this country, without subsidies, by US citizens, then yes, many things that are recycled, would not be. Then there's the question of long-term capital investment and whether it is wiser to pay more to recycle or take a huge cash hit to dig mines and build primary refining plants. As I'm sure you're aware, those issues are decided by quarterly profits, government subsidies and environmental regulations.
I think you did miss lead-acid batteries. Shops wil *pay* an unsubsidized premium of $6 ea for large scrap lead acid batteries.
Now my personal rant is spent reactor fuel rods. They absolutely, positively *should* be recycled, but the political stigma of fuel recycling created by Carter and propagated by all the subsequent presidents has forbidden it. So they sit in storage ponds at the reactor sites while the environmentalists wring their hands and whine about long-term storage. Recycling the spent fuel would create a huge amount of zero CO2 potential energy *and* solve the storage problem.
Now my personal rant is spent reactor fuel rods. They absolutely, positively *should* be recycled, but the political stigma of fuel recycling created by Carter and propagated by all the subsequent presidents has forbidden it. So they sit in storage ponds at the reactor sites while the environmentalists wring their hands and whine about long-term storage. Recycling the spent fuel would create a huge amount of zero CO2 potential energy *and* solve the storage problem.
Sure. I'm gonna cut some corners because I'm not a nuclear physist and I don't want to type all night.
Brand new nuclear fuel rods are essentially pure mixture of uranium 238 and uranium 235. The U238 is the common component of uranium ore. U235 the stuff bombs can be made out of and is separated at great cost from the U238. The fuel rod have about 96% U238 and 4% U235.
The new fuel rods have very low levels of radioactivity. On a tour of a power reactor I actually walked up within 5 feet of a bundle of new fuel rods.
Once the rods are placed into a reactor, the low numbers of neutrons naturally emitted by the rods becomes greatly multiplied. As a uranium atom emits a neutron, it is then reabsorbed by another atom, which can then emit more than one neutron. These additional neutrons go on to hit more U atoms and liberate more neutrons. In the case of a nuclear weapon, 60 or so generations of this multiplication happen in a very tiny fraction of a second, resulting in a horrific explosion.
In a power reactor, the neutrons are slowed down by a moderator, resulting in a controllable climb of radioactivity and power. Neutron absorbing control rods can be moved in and out of the core to absorb neutrons and throttle the reaction.
Anyway, as the neutron slams into uranium atom, the uranium atom doesn't remain a uranium atom. As it radiates energy and more neutrons it also splits into two or more lighter elements. The problem is the lighter elements. As the fuel "burns up", the lighter elements absorb the neutrons without emitting any. By the time 1 percent of the uranium is "burned up", there are too many of the lighter elements absorbing neutrons and the fuel rods must be replaced.
So, reprocessing involves chemically processing the "spent" fuel rods to separate out the uranium and remanufacture it into fuel rods.
Some of the problems are that in addition to the lighter elements and the unburned uranium, there is also heavy elements such as plutonium which could be separated and diverted. The plutonium can be blended back into the new fuel rods and burned again, but plutonium is a dirty word and it's not likely to happen. Another is that we are currently blending a large amount of U235 into our fuel from ex-soviet warheads, distorting the cost-savings benefits of fuel reprocessing. Another issue is the high radioactivity of the spent fuel rods, which creates some engineering challenges in the design of a reprocessing plant. These issues are not insurmountable, as the old guys at Hanford, Washington knew how to do it in the 40's.
So, I've kinda glossed over an incredably difficult and complicated matter and probably oversimplified it.
I was speaking of recycling economies at the consumer level. At the industrial level, Jim is quite correct about recycling steel, copper, lead, etc.
He's also correct about recycling uranium from reactors. It's not all that difficult to do. But, in an earlier example of political hysteria quashing good science, the nuclear waste problem was hyper-exaggerated in the 70s and 80s. So we went back to CO2-producing fossil fuel electric plants instead of pursuing nuclear power. "Not in my back yard" has turned into "in everybody's atmosphere". Yes, nuclear waste products are pretty nasty. But we know exactly where they are at the end of the day--they aren't just belched into the atmosphere.
There was an interesting editorial in this month's "Machine Design" magazine stating that curbside recycling is a net loss to the environment. The pollution and fuel costs of driving another garbage truck to each home once a week to pick up an average of 4 pounds of recyclables per household cannot be offset in recycling savings, either financially or environmentally.
Thanks, Jim. I understand about the Plutonium - but it sure seems like we're wasting a whole lot of uranium and looking for places to keep it......when we could be recycling it.
Back when we had curbside recycling pickup (we don't anymore--budget cuts), the same truck picked up the recycling trash at the same time as the rest of the trash, on the same truck. They just put the stuff in separate sides of the garbage truck.
I don't know the answer, but I'm sure it's not creating massive landfills all over the country, full of Pepsi bottles and newspapers and cans.
Maybe we should go back to not being such a disposables-addicted society; for example, we could return to returnable glass soda pop bottles. Look at all the fun kids could have gathering up empties and cashing them in at the local store, like we did. :)
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Galen
One of the biggest things that I have seen upon moving to Maine, has been the 'tree growth' laws here.
When we lived in Washington, it was 'The Law' that when you cut timber it mus tall be re-planted within two years. But not so here in Maine. I now own a wood-lot, and in getting a 'Forestry Management Plan' from a state forester to keep it in timber growth, I learned that such is not required here. Also the local officials would very much fight you at any mention of the idea of re-planting timber trees.
The local thought is to allow nature to decide if nature wants trees growing on the land.
So instead of 'wood-lot' properties that are all timber in various stages of growth, much of it is: open fields, and brush and softwood/hardwood mixes of no commercial value.
The only thing the sate really seems to allow, is spraying broad-leaf herbicides to limit tree growth by species. The forester that I bought my land from, sprays herbicides by crop-duster to do this. He sprays many square miles with herbicides to kill everything but conifers, every summer.
We moved here thinking that we would be re-planting a few acres each year, but only if we want to buy nursery trees out-of-state and smuggle them in.
:)
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sirguessalot
hi all
i just saw the flic last night
and it seems as if we have the temperature and carbon data going back 600,000 years
as well as all kinds of other data (that many either refuse to look at, or are simply unaware of)
and there seems to be a lot of misconceptions and disinformation surrounding this topic
and misplaced concern for economical factors
as well as denial of responsibility
it is the 3rd millenium,
and it seems as if the tragedy of the commons has been multiplied, amplified and exploded in our face
along with the population growth and materialism and narcissism
old habits die hard, i guess
and old habits and new toys don't go together very well
just my 2 cents
peace,
Todd
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Zixar
If the current age of the Earth is about five billion years, then 600,000 years of data, if we really have it, represents about a tenth of one percent of our planet's climatologic history. Try to predict exactly what will happen in your life over the next year from what happens to you in the next nine hours--one-tenth of one percent of a year.
There are things that we do know and can prove. Things like that the Sun is a slightly variable star--its energy output fluctuates a bit. Its variations are mostly irregular--no one can predict if it will put out more or less energy on Saturday as it did today. Natural disasters like volcanoes and prairie/forest fires happen suddenly, and can dump far more pollution into the atmosphere in a short period of time than any man made source short of a nuclear bomb. Factories are much cleaner today than they were 100 years ago. There are more trees in America today than there were in the 1700s. In short, if the guesses are correct and the Earth really is getting permanently warmer, human pollution is only a minor factor in it, if at all.
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sirguessalot
well...for what it's worth, here are some relevent links
Global Change Master Directory especially check out the "Environmental Impacts" section under "Human Dimensions"
EPA on Global Warming
Global Change Data and Information System
NOAA Global Warming FAQs
Compendium of Data on Global Change
Wikipedia: Climate Change...and here is an interesting look at the trends versus the non-trends
Climate Change: New Antarctic Ice Core Data (especially check out the last blip of the graph on this one...that red line going straight up)
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sirguessalot
like i said...multiplied, amplified, and exploding in our face
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krys
Todd - that was an impressive list of references in the first post above. I've only checked out the last one so far, but it seems it's carefully thought out and meets genuine scientific protocol. Thanks for that. There's many thins there I haven't come across yet.
With respect to Zixar's comments, I understand his position and I agree that politicians like to use this issue as a club to move us in a particular direction, and that does suck.
However, the things I'm looking at don't restrict themselves to the USA alone. I'm looking globally. As far as the planet is concerned, it doesn't matter which country or continent pumps the CO2 into the atmosphere - or if it's coming from forest fires or volcanos...it's just being seriously over-loaded.
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krys
Galen - I don't understand Maine's position on additional planting unless it is protecting it's own lumber interests and/or overall land management plan. It is interesting they they encourage conifers by removing deciduous trees. Nature does seem to allow both to grow at those latitudes in general, although the northernmost parts of Maine may be more suited to boreal forests.
It is true, BTW, that the total CO2 released from dead stands is the same whether it's done by burning or the action of decay organisms. The difference is in the rate of CO2 release. When decay organisms do it, the release is about the same as the uptake by living trees, so the net increase is zero.
The way this planet works amazes me all the time. All of the standing vegetation, and animal populations are made of carbon compounds and the source of this carbon is ultimately CO2 from the atmosphere. When speaking about CO2 as a greenhouse gas, we think in terms of thousands of pounds/year or more. Yet, in the real scheme of things, the average % of CO2 in the air hovers around a bit less than 0.5% - - one half of one percent of the total atmosphere by volume (at sea level, of course). Of course this has accumulated over many millions of years, however it is still an impressive accomplishment for the process of photosyntheses - - which has been calculated by bio-physicists to be around 33% efficient! These things make me scratch my head and go WOW! That impresses me.
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Galen
Lumber mills are shutting down. Not enough timber.
We do have lots of college educated 'foresters' who charge to consult, and to own a 'tree-lot' you have to pay a forester every ten years to make a 'management plan' for your property. Pay extra and instead of handing you one from a big stack they had printed, they will actually print it off their computer with your name on the front page.
So the forestry industry seems to have a lot of folks in it, just fewer and fewer loggers, timber-mills, logging trucks, and paper mills, and chip mills.
:)
The 'modern forest industry' is more college graduate, college research studys and state forester oriented. They are phasing out the folks who actually touch trees and wood.
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krys
Sorry, Galen. I didn't realize how depressed that industry is in Maine.
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Galen
Our local papermill just closed a couple months ago. They accounted for just over a 1/3 of the local town's tax budget. [Well not in MY town, but the next town over, they are a bigger town, they have a post office and a gas station. My town is much smaller. But we do share their zip code.]
I dont know. it seems to me, that with so much empty forest land. If they would jsut require replanting, then every 20 years or so each plot could be timbered again, and it would keep the industry going.
Instead they aim at being able to re-timber in 80 years, from the previous cutting. Which seems to me is really stupid. But I am not a native Mainiac, so I just dont get it.
It is pretty, and rural and has lots of hunting and fishing. :)
We are way off-topic here, sorry folks!
I did not want anyone to think that re-planting was being done everywhere in all of U.S. forests.
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YIdon'tgotochurch
Belle replied,
I'm with you, Belle, Gore has the personality of a fence post and might be smarter than the average high school graduate, but imho, if it was 3pm and he said it was 3 o'clock, I'd still call time service.
I think of him and a lot of people like him as though they were "town cryers". Shouting at the rain because they think it will get them all wet. (It won't if they get out of it).
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Galen
Dont forget that it was Gore who inented the internet, right after he invented the computer.
:)
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Jim
Zixar wrote:
I guess my biggest question would be your definition of "economical". I know that scrap steel is so valuable that China's demand for it has pushed up the price of finished steel dramatically. And the price of both lumber and concrete with it.
The price paid for scrap copper and brass just jumped off the charts, alledgedly because of the China demand to build their infrastructure.
I watch containers loaded with steel, AL and electronics scrap heading for China and India every week at the local scrap/recycling yard.
If, by economical, you mean that it would be recycled in this country, without subsidies, by US citizens, then yes, many things that are recycled, would not be. Then there's the question of long-term capital investment and whether it is wiser to pay more to recycle or take a huge cash hit to dig mines and build primary refining plants. As I'm sure you're aware, those issues are decided by quarterly profits, government subsidies and environmental regulations.
I think you did miss lead-acid batteries. Shops wil *pay* an unsubsidized premium of $6 ea for large scrap lead acid batteries.
Now my personal rant is spent reactor fuel rods. They absolutely, positively *should* be recycled, but the political stigma of fuel recycling created by Carter and propagated by all the subsequent presidents has forbidden it. So they sit in storage ponds at the reactor sites while the environmentalists wring their hands and whine about long-term storage. Recycling the spent fuel would create a huge amount of zero CO2 potential energy *and* solve the storage problem.
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krys
Would you please explain this a bit?
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Jim
Sure. I'm gonna cut some corners because I'm not a nuclear physist and I don't want to type all night.
Brand new nuclear fuel rods are essentially pure mixture of uranium 238 and uranium 235. The U238 is the common component of uranium ore. U235 the stuff bombs can be made out of and is separated at great cost from the U238. The fuel rod have about 96% U238 and 4% U235.
The new fuel rods have very low levels of radioactivity. On a tour of a power reactor I actually walked up within 5 feet of a bundle of new fuel rods.
Once the rods are placed into a reactor, the low numbers of neutrons naturally emitted by the rods becomes greatly multiplied. As a uranium atom emits a neutron, it is then reabsorbed by another atom, which can then emit more than one neutron. These additional neutrons go on to hit more U atoms and liberate more neutrons. In the case of a nuclear weapon, 60 or so generations of this multiplication happen in a very tiny fraction of a second, resulting in a horrific explosion.
In a power reactor, the neutrons are slowed down by a moderator, resulting in a controllable climb of radioactivity and power. Neutron absorbing control rods can be moved in and out of the core to absorb neutrons and throttle the reaction.
Anyway, as the neutron slams into uranium atom, the uranium atom doesn't remain a uranium atom. As it radiates energy and more neutrons it also splits into two or more lighter elements. The problem is the lighter elements. As the fuel "burns up", the lighter elements absorb the neutrons without emitting any. By the time 1 percent of the uranium is "burned up", there are too many of the lighter elements absorbing neutrons and the fuel rods must be replaced.
So, reprocessing involves chemically processing the "spent" fuel rods to separate out the uranium and remanufacture it into fuel rods.
Some of the problems are that in addition to the lighter elements and the unburned uranium, there is also heavy elements such as plutonium which could be separated and diverted. The plutonium can be blended back into the new fuel rods and burned again, but plutonium is a dirty word and it's not likely to happen. Another is that we are currently blending a large amount of U235 into our fuel from ex-soviet warheads, distorting the cost-savings benefits of fuel reprocessing. Another issue is the high radioactivity of the spent fuel rods, which creates some engineering challenges in the design of a reprocessing plant. These issues are not insurmountable, as the old guys at Hanford, Washington knew how to do it in the 40's.
So, I've kinda glossed over an incredably difficult and complicated matter and probably oversimplified it.
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Zixar
I was speaking of recycling economies at the consumer level. At the industrial level, Jim is quite correct about recycling steel, copper, lead, etc.
He's also correct about recycling uranium from reactors. It's not all that difficult to do. But, in an earlier example of political hysteria quashing good science, the nuclear waste problem was hyper-exaggerated in the 70s and 80s. So we went back to CO2-producing fossil fuel electric plants instead of pursuing nuclear power. "Not in my back yard" has turned into "in everybody's atmosphere". Yes, nuclear waste products are pretty nasty. But we know exactly where they are at the end of the day--they aren't just belched into the atmosphere.
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Jim
Zixar,
There was an interesting editorial in this month's "Machine Design" magazine stating that curbside recycling is a net loss to the environment. The pollution and fuel costs of driving another garbage truck to each home once a week to pick up an average of 4 pounds of recyclables per household cannot be offset in recycling savings, either financially or environmentally.
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krys
Thanks, Jim. I understand about the Plutonium - but it sure seems like we're wasting a whole lot of uranium and looking for places to keep it......when we could be recycling it.
Is anybody anywhere recycling it?
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Linda Z
Back when we had curbside recycling pickup (we don't anymore--budget cuts), the same truck picked up the recycling trash at the same time as the rest of the trash, on the same truck. They just put the stuff in separate sides of the garbage truck.
I don't know the answer, but I'm sure it's not creating massive landfills all over the country, full of Pepsi bottles and newspapers and cans.
Maybe we should go back to not being such a disposables-addicted society; for example, we could return to returnable glass soda pop bottles. Look at all the fun kids could have gathering up empties and cashing them in at the local store, like we did. :)
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