Archived posting to the Leica Users Group, 2006/02/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]OK, now I get it - but our nuclear power companies are starting to make caves. All the best! Raimo K Personal photography homepage at: http://www.uusikaupunki.fi/~raikorho ----- Original Message ----- From: "Douglas Sharp" <douglas.sharp@gmx.de> To: "Leica Users Group" <lug@leica-users.org> Sent: Friday, February 03, 2006 7:44 PM Subject: [Leica] Radioactive waste - out of sight, out of mind > Sorry Raimo, > I should have written "for its volume", that's why it's called enriched > uranium.i.e. more radiation in a small space. As a comparison, a chunk of > haematite iron ore is not strongly magnetic, but processed into iron or > steel the magnetism can be significantly stronger (in effect also a form > of radiation). > As to the usability of radioactive substances, you have to consider the > radiating isotopes U-235 and U-238, the former is common, the > concentration of the latter is the result of the enrichment process which > makes uranium suitable as a nuclear fuel. The common ores, such as > pitchblende, are relatively harmless before processing. > On a geological time scale caverns are a very dodgy business, as are salt > domes. What may appear impervious at first sight just isn't - think about > it - why are most caves and tunnels damp? Why do engineers tunneling > through the raw mountain rock of the Alps have such massive problems with > water, liquified clay slurries (a by-product of eroded granites), sand > slips and structural failure of bed-rock under pressure? > > Geology is in a state of constant movement, not usually at a scale at > which we can actually watch it, but let's say a few cm or inches a year - > up down and sideways, this mounts up to a fair amount when you consider > the half-life of radioactive waste - the time it takes for half of the > radioactivity to dissipate - after these tens of thousands of years the > stuff is only half as radiactive as it was in the first place. > Particularly in the case of dense igneous rocks there is a high degree of > tension caused by movements which is often revealed in earthquakes - when > the tension or pressure is released all at once, this may be along fault > lines, above magma bodies or plumes, or just a matter of two continental > plates, which usually slide sedately over or under each other > (subduction), at a rate of inches per year at shelf boundaries, which tend > to get stuck to each other and then rip apart when the pent up force is > too much. > In your country, the Fenno-Scandian Shield is one of the slower moving > parts of plate-tectonics, but it does move all the same - that's why there > are so many sharp edged mountains and deep Fjords in Scandinavia. > Although the Belgian solution seems, at first sight, to be rather > adventurous, a relatively thin clay layer (Boom-clay in this case) is less > pervious to gases and liquids, and more flexible in accomodating movement > than are granites, basalts or rock salt. Radiation is worse than liquids > and gases, it will penetrate just about anything and leave a path of > destruction in its wake. > Nuclear waste disposal is a matter of thinking "out of sight, out of mind" > maybe our great-great squared grandchildren will be the ones having > problems with it. > None of us should ever stop worrying about this slowly ticking time-bomb. > Hope this clarifies it a bit > cheers > Douglas > > Raimo K wrote: > >> How can used stuff have more radiation than unused? If it had, it would >> be usable. >> OK, it is concentrated into granules but if you store it deep in stable >> rock caves (like we plan to do in Finland) and take into account the >> immense mass of stone around the storage I see no way it can have >> increased radiation compared with hot uranium mines. >> All the best! >> Raimo K >> Personal photography homepage at: >> http://www.uusikaupunki.fi/~raikorho >> >> >> ----- Original Message ----- From: "Douglas Sharp" <douglas.sharp@gmx.de> >> To: "Leica Users Group" <lug@leica-users.org> >> Sent: Thursday, February 02, 2006 12:51 AM >> Subject: Re: [Leica] RE: LUG Digest, Vol 31, Issue 221 >> >> >>> Hello Frank, >>> the refined stuff has a much higher radiation output than the ores - >>> think of tiny granules of uranium mixed in with great chunks of rock >>> which, at least partially stop the radiation, and, btw, make uranium >>> mines so hot. >>> There is one method of sealing nuclear waste which is effective as far >>> as it goes, sealing it in glass with a large proportion of lead (which >>> doesn't shield from radiation, it absorbs it and changes over time) this >>> has again the inherent problem of heat, the energy has to come out >>> somewhere. Before somebody suggests dropping it into volcanos, the >>> molten lava is much too close to the surface, getting sprayed with >>> molten rock is bad enough, but making it radioactive too is a bit much. >>> >>> As to the plastics, there are some fascinating developments on the way >>> with high quality plastics made from potato starches and waste straw >>> from maize crops, then there's always multitudes of natural vegetable >>> oils which haven't really been tested for making the polymers we need >>> for plastics. >>> The power of biological products can be seen in the recipe for casein >>> glue - just mix curds and chalk - one of the best and oldest glues there >>> is. >>> The energy business is going to become one of the main areas for the >>> development of genetically modified plant strains, the other area is the >>> creation of bacteria which can reduce waste plastics to their original >>> source materials - but that is a pandora's box I don't care to think >>> about - just let a bacterium like that get out of hand or mutated and >>> start chewing up plastics just where it shouldn't, I shudder at the >>> thought. >>> It's interesting that most of the large oil companies are working very >>> hard in this direction, particularly Shell and BP, they want to have the >>> market cornered when the time is ripe. There was a research project for >>> loosening up heavy oil deposits in a reservoir by dropping anaerobic >>> bacteria down through the borehole, but I left the business before >>> hearing more about it. >>> The last stuff I was working on was the localisation of deep seated >>> magma bodies for geothermal energy production in Tuscany >>> (Larderello,where they've been doing it since the early 1920s) my theory >>> for variations in their heat production was that these bodies are also >>> subject to tidal forces caused by the position of the moon pulling them >>> closer to the surface, unfortunately I never did hear what came of that >>> either. At least there was a significant increase in microseismicity >>> (tiny earth tremors) at full moon, which seems to support my theory. >>> To get back on track, the visit to ENEL GreenPower in Pisa was a >>> wonderful opportunity to wander around that beautiful city with a >>> camera. >>> cheers >>> Douglas >>> >>> Frank Dernie wrote: >>> >>>> Douglas, >>>> I have always wanted to ask a specialist this question, and it looks >>>> like you may just be the person......... >>>> What is wrong with burying nuclear waste in the exhausted mines from >>>> which it originated? Presumably it won't be any more dangerous there >>>> than the raw nuclear material originally mined???? >>>> The biggest concern I have re oil is not its use as a fuel, that seems >>>> a terrible waste to me, but as the raw material for manufacturing >>>> materials such as plastics for which we have no reasonable >>>> alternative. >>>> Frank >>>> >>>> On 1 Feb, 2006, at 19:30, Douglas Sharp wrote: >>>> >>>>> The technologiy is clean enough, and close to being as safe as it can >>>>> be - the problem is still nuclear waste. As a production and >>>>> exploration geophysicist I've worked on nuclear waste storage sites, >>>>> working and prospective, in Germany, Belgium, Switzerland and a few >>>>> other places. For the long-term storage of nuclear waste there is NO >>>>> really safe solution, that stuff stays highly radioactive on a >>>>> geological time scale. >>>>> Salt dome caverns are no good - salt moves and migrates so you've >>>>> never got a constant thickness shielding your waste, the Swiss >>>>> solution of putting it in caverns blasted out of native impervious >>>>> (supposedly) rocks is better but radiactive gases (Radon for example) >>>>> always manage to find a way to the surface. The Belgian method of >>>>> hiding it under a thin layer of impervious clay isn't a long term >>>>> solution either. >>>>> So what do we do with it? Shooting it into the sun is the only real >>>>> way of getting rid of it, there's been enough dropped into the sea >>>>> and more than enough buried already, these "fly-dumps" will take >>>>> their revenge on the environment one of theses days. >>>>> You say that present day technologies are safe, I agree - problem >>>>> is, even the most recent reactors just haven't been built with these >>>>> new technologies, Temsvar in the Czech Republic is one of the newest >>>>> NPSs >>>>> and is just not safe, the same applies to the latest French reactors, >>>>> Germany's reactors have been plagued with problems and Sellafield in >>>>> the UK is a dirty word already. No need to mention reactors in the >>>>> former soviet block countries....... >>>>> >>>>> Fusion power is pie-in-the-sky (unless the billions for defence are >>>>> re-channeled), you might just as well try a further development of >>>>> Nikolaus Tesla's idea by building orbiting spaceborne solar power >>>>> stations transmitting power as high energy microwave frequencies back >>>>> to earth, though I dread to think what would happen if a plane flew >>>>> through one of those tight banded transmissions. >>>>> The only clean options are terrestrial solar energy farms, wind and >>>>> tidal energy and geothermal energy - these are the only future I can >>>>> see in power production. >>>>> >>>>> Some of the latest developments reek of science fiction but could be >>>>> effective - half mile high chimneys set up in desert regions, the >>>>> temperature differential between ground level and the top creates >>>>> winds of incredible velocities, all you have to do is put aturbine in >>>>> the way of it. Using waste energy (off peak production is always too >>>>> high and just gets wasted) from conventional power stations to pump >>>>> water into high level reservoirs >>>>> to run hydroelectric turbines at peak demand times, storing energy as >>>>> compressed air in salt domes is another option, use it to supply the >>>>> energy needed to get gas turbines running. >>>>> >>>>> None of these, however give us any kind of solution for automotive >>>>> transport - when the oil runs out we're going to back with sailing >>>>> ships and steam engines again, individual or personal transportation >>>>> will be the rich man's game. >>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> Leica Users Group. >>>> See http://leica-users.org/mailman/listinfo/lug for more information >>>> >>>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >> >> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information >> >> > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information