Archived posting to the Leica Users Group, 2006/02/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]A few, fortunately very few, years after we bought our farm in Easton NY, a lovely old (for this country) 1860 farmhouse, we discovered that there were faint traces of radon in our cellar, a bare dirt floor and heavy limestone walls. Thereafter, we regularly left cellar windows open to vent. Seth ----- Original Message ----- From: "Adam Bridge" <abridge@gmail.com> To: "Leica Users Group" <lug@leica-users.org> Sent: Friday, February 03, 2006 8:57 PM Subject: Re: [Leica] RE: LUG Digest, Vol 31, Issue 221 > Radon is definitely one of the sources to avoid. Radon is an > alpha-emitter. Normally alpha isn't a big deal as long as you don't > let it into your body - a piece of paper will stop it. But Radon is a > gas and so the gas goes into your lungs where the radiation is applied > directly to unprotected internal tissues - so caring about radon makes > a lot of sense. Fortunately basements can be vented. > > Adam > > On 2/3/06, Douglas Sharp <douglas.sharp@gmx.de> wrote: >> Most of Cornwall (UK) is built on granite bed-rock, many houses there >> suffer from high concentrations of naturally occuring radioactive radon >> gas seeping into cellars through the bedrock. >> Douglas >> >> Raimo K wrote: >> >> > Thanks for the clarification of the picture - but I still see no >> > radiation escape from the deep granite caves. >> > All the best! >> > Raimo K >> > Personal photography homepage at: >> > http://www.uusikaupunki.fi/~raikorho >> > >> > >> > ----- Original Message ----- From: "Adam Bridge" <abridge@gmail.com> >> > To: "Leica Users Group" <lug@leica-users.org> >> > Sent: Thursday, February 02, 2006 7:55 PM >> > Subject: Re: [Leica] RE: LUG Digest, Vol 31, Issue 221 >> > >> > >> >> When Uranium is fissioned two different elements are created and each >> >> of these elements is unstable (usually quite seriously unstable) and >> >> so they decay into different nuclides by various mechanisms, all of >> >> which give off serious amounts of gamma radiation. The half-lives of >> >> these fission products vary but the entire chain takes tens of >> >> thousands of years to reach low-level proportions. The spent fuel >> >> isn't explosive although it does produce heat as a result of the >> >> radioactive decay. They don't burn, in general they are metals >> >> >> >> The amount of radiation in a reactor core which has never been >> >> critical, that is to say a self-sustaining nuclear reaction has never >> >> happened in it, is quite small. Before the core was loaded into PARCHE >> >> I was able to look up inside it with no protection except for the >> >> requirement to keep everything VERY clean. >> >> >> >> But at the end of life the amount of radioactivity is quite vast - >> >> many mega-Curies of radioactivity. (The Curie itself is a huge amount >> >> of radioactivity, it represents a certain number of disintegrations >> >> per second. Normal limits for things are normall expressed in >> >> micro-micro-Curies to give you an idea.) >> >> >> >> As a rough approximation, if you are 1 meter away from a 1 Curie >> >> source of gamma-emmiting you'll receive an exposure of 1 REM/hr. REM >> >> is a measure of biological damage produced by radiation. >> >> >> >> The limit for non-radiation workers are .1 REM/year over and above >> >> what you get from normal background radiation - ie cosmic rays etc. If >> >> you live at altitude you get more than if you live at sea level for >> >> example. Medical/Dental x-rays aren't counted in this either. You >> >> typically get about 200 mili-rem from natural souces - radon gas which >> >> happens naturally is the biggie - and 40 mili-REM from x-rays per >> >> year. >> >> >> >> An exposure of (oh boy these numbers are hazy, it's been a long time) >> >> of 50 REM over a short period will produce identifiable changes in >> >> your blood. 100 Rem acute will make you ill, the threshold of >> >> mortality is 150 REM and I think the 50/50 dose is 500 REM IF you get >> >> the best medical treatment - meaning 50% of the people exposed will >> >> die. 100% mortality is 800 REM. >> >> >> >> Radioactive waste from nuclear reactors is in the realm of mega-REM. >> >> The decay of the fission products produces heat. Many of the elements >> >> are themselves corrosive. So it's a tricky problem - especially if you >> >> want to have something stored unguarded. Most fuel-rods are stored >> >> deep under water in pools that are on the grounds of the reactor plant >> >> that produced them. In fact, in the US this is where they have to STAY >> >> since there is no long-term storage facility. >> >> >> >> As you might guess they are not easy to steal, either. Somehow you'd >> >> have to take over a facility, find a big lead container, use remote >> >> handling equipment, remove the rods, put them into the container, >> >> move them. They are typically in stainless steel or zirconium cladding >> >> of some sort or other. Trying to grab one without the remote handling >> >> would be seriously ugly for the people attempting it. It ain't like >> >> the movies. >> >> >> >> I hope this was useful and not too technical. My days as a reactor >> >> operator are three decades past. I know that new units of measure are >> >> now included in the SI system but I haven't had a reason to keep up. >> >> >> >> Adam Bridge >> >> >> >> On 2/2/06, Raimo K <raimo.m.korhonen@uusikaupunki.fi> 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 >> > >> > >> > >> > _______________________________________________ >> > 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 >