In article , Todd Rich wrote in part:

Did you bother to even read the Oak Ridge report I linked to? Here is a
highlight for you:

:Based on the predicted combustion of 2516 million tons of coal in the
:United States and 12,580 million tons worldwide during the year 2040,
:cumulative releases for the 100 years of coal combustion following 1937
:are predicted to be:

:U.S. release (from combustion of 111,716 million tons):
:Uranium: 145,230 tons (containing 1031 tons of uranium-235)

:Thorium: 357,491 tons

:Worldwide release (from combustion of 637,409 million tons):

:Uranium: 828,632 tons (containing 5883 tons of uranium-235)

:Thorium: 2,039,709 tons

Note that this is estimated totals for 35 years in the future, but for a
typical plant in 1982:

:For the year 1982, assuming coal contains uranium and thorium
:concentrations of 1.3 ppm and 3.2 ppm, respectively, each typical plant
:released 5.2 tons of uranium (containing 74 pounds of uranium-235) and
:12.8 tons of thorium that year

Keep in mind that with the uranium being about 99.3% U-238 which has a
halflife only a few times that of U-235, most of the radioactivity is from
the 238 and not the 235.

Also, a curie of uranium or thorium is not merely a curie of radioactive
material. U-238's first decay product is Th-234, which has a halflife of
24 days. So, wherever you have a curie of U-238, within a few months you
approach having a curie of Th-234 in addition to the curie of U-238.
(U-235 also does something like this, although it produces Th-231 -
halflife 25.6 years. Where you put a curie of U-235, in several decades
you approach also having a curie of Th-231.)

Neither of these thorium isotopes are much of the thorium tonnage
mentioned above, since that would be Th-232.

Th-234 decays to Pa-234, which has a halflife of about a week. So
wherever you have a curie of Th-234 you soon have a curie of Pa-234. That
becomes U-234, which thankfully has a halflife of about a quarter million
years. So a curie of pure U-238 soon becomes 3 curies of radioactive
material but then stays that way for a while - but in about a million
years you have approaching 11 curies (7 curies of shortlife alpha emitters
and 4 curies of shortlife beta emitters) of the decay products between
U-234 and Pb-206.

Th-231 decays to Pa-231, with a halflife of 34,300 years. So a curie of
U-235 becomes close to 2 curies of radioactive material within a century,
but largely levels off from there - unless you count the 100,000 year
range when that approaching-a-curie of Pa-231 will have approaching-9
curies of short-life decay products (6 of this 9 being alpha emitters and
3 of this 11 being beta emitters) on the way to Pb-207.

The main-tonnage Th-232 goes through 6 alpha decays and 4 beta decays on
the way to Pb-208, with the logest halflife product in between 1.9 years.
So within a decade, you approach having 10 curies of radioactive decay
products wherever you put a curie of Th-232.

That 5.16 or so tons of U-238 per year from a typical coal-fired power
plant amounts to 3.55 millicuries of U-238, plus 7.1 millicuries of
soon-to-materialize decay products.

That 74 pounds of U-235 per year from a typical coal-fired power plant
amounts to another .16 millicurie - plus .16 millicure of a
soon-to-materialize decay product.

The 12.8 tons of thorium amounts to another 2.9 millicuries - and the 29
millicuries of decay products.

Looks like a typical coal fired power plant emits into the environment
(including within-a-decade-appearing decay products) about 42-43
millicuries annually.
I don't know what the average annual leakage from nuclear plants and
waste storage facilities are, but I surely doubt the NRC would let me dump
42 millicuries per year of anything into the atmosphere, oceans, rivers,
landfills, etc.
It appears to me that if a nuclear plant near me leaked 43 millicuries
of anything into a river or into the air, it would be news.

- Don Klipstein )