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Re: radioactivity from fossil fuel power stations



Dr. Cohen, 



I understand your argument better now, thanks for sending a more

complete explanation.  However the coal itself does contain uranium and

thorium, and so would be a source of radon while in situ.  I don't

believe that the rocks commonly found in association with coal

(sandstones, silts, and shales) have significantly different

concentrations of uranium, thus the change in exposure would be

negligible once these are exposed.  Just as the carbon in the coal

produces no radon, neither does the silica in the sandstone.



>From Alex Gabbard's article "Coal Combustion: Nuclear Resource or

Danger"

at http://www.ornl.gov/ORNLReview/rev26-34/text/colmain.html



"Trace quantities of uranium in coal range from less than 1 part per

million (ppm) in some samples to around 10 ppm in others. Generally, the

amount of thorium contained in coal is about 2.5 times greater than the

amount of uranium. For a large number of coal samples, according to

Environmental Protection Agency figures released in 1984, average values

of uranium and thorium content have been determined to be 1.3 ppm and

3.2 ppm, respectively."



I suppose you could argue that mining and burning coal releases the

radon from the coal and remaining rocks "prematurely" compared to

natural erosion, but this would be far outweighed by the effects of

quarrying for sand and gravel operations, the largest single industry in

the U.S.



In general, I think there are stronger arguments you can use than the

geologic one.  For example, real deaths.  From a recent press release

from the Campell County (Tennessee) Historical Society: "About 300 Coal

Creek

miners, many of them veterans of the Coal Creek War, perished in mine

disasters in 1902 (Fraterville) and 1911 (Briceville).  Mine disasters

like these raised public awareness of the hazards of mining, resulting

in

advances in mine safety practices.  In the early part of the 20th

century,

thousands of coal miners died in the United States each year.  In 2000,

coal mining fatalities in the U.S. numbered 38."  Thankfully, we've made

considerable progress in this area, though I would be interested in how

38 deaths per year compares to nuclear for the same amount of energy

produced.



Regards,

Susan



BERNARD L COHEN wrote:

> 

>         My treatment of the radiation exposures from coal burning, given

> in HEALTH PHYSICS 40:19;1981, adds up effects over hundreds of thousands

> or millions of years -- very near future doses are negligible by

> comparison. Radon administers dose by percolating up thru the ground from

> roughly the top one meter, so that top meter is what we are concerned

> with. The ground surface erodes away at a rate of about one meter per

> 20,000 years, so all material in the ground will eventually spend about

> 20,000 years in this top meter, administering doses from radon which is

> killing, according to NCRP, ICRP, etc, about 15,000 Americans every year.

> If you figure out how much uranium is in the top meter of U.S. soil, and

> consider the fact that it kills 15,000 people per year for 20,000 years,

> this works out to be 3.7 deaths per ton of uranium before it is eroded

> away into the oceans. This toll will eventually be taken by every ton of

> uranium in the ground. For example, when coal is burned to generate

> electricity, the uranium (+Th + Ra) released from impurities in the coal

> (average 1 ppm) will kill 11 people per GWe-year, with these deaths

> occurring over the next 100,000 years. That is the "short term" effect.

> >From the longer term perspective, if the coal had not been mined it would

> eventually reach the top meter of the ground -- if it came from 100 meters

> deep, this would occur after 100 x 20,000 = 2 million years. During its

> 20,000 years in the top meter, the carbon in the coal would produce no

> radon, but if the coal had been mined out, in the 20,000 years during

> which it would have been in the top one meter, it is replaced by average

> rock which does contain uranium (2.7 ppm) and thus releases radon. This

> extra uranium (+Th +Ra) causes 30 deaths per GWe-year. To calculate this,

> coal burning consumes 3 E6 tons/ GWe-year so the extra uranium producing

> radon is 3 E6 x 2.7 E-6 = 8.1 tons of uranium; with 3.7 deaths per ton of

> uranium, this gives 8.1 x 3.7 = 30 deaths.

>         Note that mining uranium out of the ground to produce nuclear

> electricity - 160 tons / GWe-year - *saves* 160 x 3.7 = 590 lives per

> GWe-year. With a correction for mill tailings, this is reduced to 420

> lives saved.

>         If you object to this treatment because we shouldn't be worried

> about deaths millions of years in the future, note that this was not my

> idea to do so -- that is what the anti-nukes insist on. Similarly for my

> use of linear-no threshold theory in the calculation. my viewpoint on

> these matters is expressed in my paper on "Discounting in assessment of

> future radiation risks", HEALTH PHYSICS 45:687ff;1983.



-- 

.....................................................

Susan L. Gawarecki, Ph.D., Executive Director

Oak Ridge Reservation Local Oversight Committee

                       -----                       

A schedule of meetings on DOE issues is posted on our Web site

http://www.local-oversight.org/meetings.html - E-mail loc@icx.net

.....................................................

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