Posted by Karl Johanson on June 19, 2005, 2:04 am
Chernobyl spread a fair amount of Plutonium about. The only confirmed
long term effects in the area have been Thyroid tumours, related to
radio-Iodines. Lung cancers (what you'd expect from significant doses of
inhaled Plutonium), haven't increased.
Above ground nuclear weapons testing spread thousands of pounds of
Plutonium into the atmosphere. In spite of some claims that doing that
with one pound of Plutonium would kill everyone, there's still around
6.3 billion people alive. Plutonium has significant dangers, but the
dangers aren't as great as some have suggested.
The collapse of the World Trade Centre released natural radio-isotopes.
The following is a rough estimation only of the amount of naturally
occurring radioactive material released by the WTC collapse. The numbers
are not intended to be exact. The estimation is listed here merely to
show that there was a significant release of radioactive material (and I
would personally appreciate any feed back which may lead to fine tuning
of the figures).
-Each tower of the WTC had roughly 600,000 tons of concrete, for a total
of around 1,200,000 tons for the two towers combined.
-Uranium exists in the Earth's crust at roughly 4 parts per million.
-If we assume that the Uranium content of the concrete was roughly 4
parts per million (it likely varied from that average somewhat) then
there would be roughly 4.8 tons of Uranium.
-Thorium is about 4 times as common as Uranium. Making a similar
assumption as for Uranium, we could expect somewhere around 19 tons of
-There'd also be around 37 tons of Potassium 40 and around 33 tons of
Rubidium 87 (also assuming they are in the concrete in roughly the
percentages they are in the Earth's crust).
-When Thorium and Uranium break down, they form series of other
radioactive materials, including isotopes of Radium and Radon. These
daughter isotopes of Thorium and Uranium would, of course, be in the
concrete as well.
If a 'dirty bomb' released say 1% of the above materials over New York,
I expect there would be some suggesting the city be evacuated.
Posted by Roy Boy on June 23, 2005, 4:10 pm
Karl Johanson wrote:
I would not consider the greater Chernobyl area to be a hotbed of
economic activity. To turn 50 of our greater metropolitan areas into
the radioactive equivilents of Chernobyl plus a 5 mile radius would be
Above ground nuclear weapons testing was banned at the height of the
cold war. There were a number of reasons for this timing, one of them
being that plutonium has significant dangers.
I have no doubt that I will be educated if the following information is
incorrect, but I beleive the old meme about a 1 pound dose of plutonium
being globally lethal had a tag line that it be ingested.
I also think the one-pound amount refered to a certain Plutoimium
isotope, and I regret that I cannot supply the information as to which
isotope is referenced with the one-pound plutonium meme.
This is the assumption that underpins all else in the chain of
reasoning leading to an estimate of 4.8 tons of uranium in the Twin
Towers concrete plus other radiactive goodies.
Should your assumption prove correct, then one can extend your
reasoning way past the Twin Towers to all concrete structures. That
would be pretty scary.
I suspect that while uranium may exist in the Earth's crust at roughly
4 parts per million, using your number, that the distribution of
uranium in the Earth's crust is highly uneven, so that raw materials
used to make concrete have a much lower incidence of radioactive
element concentration than the local Uranium mine.
Never-the-less, I believe your basic point about radioactive materials
being present in building materials, and in building sites is ususally
very much under-appreciated and that good documentation SHOULD exist to
prove that the raw materials used to produce building supplies are
below any health hazard thresh-hold as well as documention showing that
a proposed building site also falls well below levels of radioactivity
In regards to the Twin Towers and the potential contamination of
thousands of people, I am much more concerned about the amount of
asbestos used in the construction of the Twin Towers.
In the aftermath of their collapse, there were no special measures
taken to ensure that the local population was protected from potential
asbestos contamination and EPA tests reported a lack of asbestos in the
thick cloud of dust many inhaled. I am leery of these EPA tests, as
asbestos doesn't simply disappear from the planet due to a building
collapse and because the concrete dust cloud would be a natural trap
for asbestos fibres. But, we shall see.
Assuming that 1% of the quantities that you estimate were released in a
dirty bomb over New York; given worst-case wind patterns, I certainly
agree with you that many would suggest the city be evacuated.
In summary, I do not think one can apply average radioactive element
concentrations in a concrete way when analysing the radiactive
lethality of our local environment, including homes, businesses, and
Posted by Richard Bell on June 24, 2005, 12:46 am
The first step to turning any region into an equivalent of Chernobyl is to
get an RBMK1000 reactor built there. Hard enough to do when we did not
know how bad the design was. The amount of radioactives spread by the
Chernobyl disaster is measured by the truckload. Terrorists stealing a few
pounds of radioactives is not too difficult to imagine, but for a Chernobyl
scale contamination, we need a reactor's worth of irradiated material.
Do you seriously expect anyone to afford to build anything?
There is enough potassium40 in a banana peel to cause it to be treated as
low level radioactive waste.
As for requiring building sites to be below a "safe" level of radioactivity,
there are only two alternatives: Evacuate most of the continental US east
of the Mississippi, or seriously increase what constitutes a safe exposure.
I prefer the second, as realistic exposure guidelines would make nuclear
power cost less.
Posted by Roy Boy on July 10, 2005, 6:02 pm
Richard Bell replied to Roy Boy's post and replied:
Imagine this. Imagine a concerted attack on a large American city's
subway system with just the few pound of radiactives that you describe
exploded at many key locations in the transit system. Imagine how long
it would take to put the subway infrastructure back into service in the
aftermath of such an event. Imagine running New York without the use
of its subway system for 3-6 months. Imagine the amount of economic
dislocation such an event would cause in NYC and its subsequent ripple
effects throughout the US economy.
I do not believe Gieger Counters or their modern equivilents to be
economic deal breakers if they were used to survey potential building
I am afraid I cannot see the huge cost adders you envision to be the
result of checking materials and builing sites to ascertain their
natural radiation level. It just isn't that hard to do.
This is a fascinating statement. I do not disbelieve it, but I would
certainly love to know the source of your data that supports your
The arguments that rage over what constitutes a "safe" level of
background radioactivity continue, with no end in site. Again, it
would be most helpful were you to supply the specifics concerning the
amount and type of radioactivity that should propell such a mass
The arguments over what constitutes realistic plant exposure guidlines
do not appear to be settled either. But our nuclear power plants,
baring accidents, and not considering the waste end-products of the
power production process, emitt extreamly low levels of any type of
radiation, so I think a new and looser standard would be a moot point
as far as power plant cost is concerened.
No one would seriosly wish to reduced the splendid radiation
containment that our current plants now have, so new plants would most
likly be built to the same standard, if for no other reason than PR.
Its pretty tough to go backwards in standard-setting in such a
politically sensitive area.
Posted by Eric Gisin on July 11, 2005, 2:53 pm
Nope, you do it.