Newsgroups: sci.energy
From: John De Armond
Subject: Re: Nuclear waste disposal
Message-ID: <6374s_@dixie.com>
Date: Thu, 10 Mar 94 10:21:58 GMT

niteowl@u.washington.edu (Jamie Jamison) writes:

>	I saw an article a few days back where Hazel O'Leary stated that
>the US was going to lose about 20% of its power grid in the next five
>years due to the fact that many nuclear plants would have to shut down
>because of waste disposal problems.

>	I was looking at this and wondering why high level nuclear wastes
>aren't diluted before they are disposed of. It seems to me that many
>radionuclides would be much safer and easier to handle if you diluted
>them about 100 to 1 with iron or some other cheap metal and then disposed
>of them that way. Obviously this isn't the case as someone much smarter
>than I am would have proposed it long ago and we might be doing it now.
>Can anyone enlighten me on the problems with this solution?

It is important to understand what is going on here.  US nuclear plants
were designed to fit into a system whereby the government processes
and enriches uranium, fabricates and/or sells fuel to quasi-private
companies for fabrication into fuel elements.  They then sell the
fuel to the utilities to burn.  After removal from the reactor,
the utility would store the fuel for 6 mos or so to let the short
lived stuff die off.  Then the utility would ship the fuel back
to a government facility for reprocessing into new fuel stock.
Now us libertarians immediately recognize the formula for failure -
getting the government involved in private enterprise but nontheless,
that was the equation.

The first jam-up was that the government turned the reprocessing
project into a boondoggle, typically rife with corruption and waste.
The real monkeywrench in the works, as with the rest of the country,
was Carter.  Carter tried to hide his anti-nuke agenda behind
"proliferation".  Somehow in Carter's twisted logic, reprocessing
would enable some unnamed terrorist to somehow steal some of
the mixed plutonium isotopes refined from the old fuel and make
a bomb out of it.  That the physics involved makes it effectively
impossible was no matter.  Carter ordered a moratorium on
reprocessing.  This happened in the 77-78 timeframe.

Now the utilities were in a jam.  They had built their spent fuel
storage facilities to handle only a couple of core loads because
it was designed only as transient storage until the fuel cooled
enough to ship.  These storage facilities consist of a large
and deep swimming pool filled with water.  Typically over 100 ft
deep, the fuel is stored in racks in the bottom while the water
cools and shields it.  Since there was now no place to send the
spent fuel, the utilities were suddenly faced with on-site
storage of N cores where N could range to as much as the number
of cores consumed during the life of the plant.  A plant eats a
whole core every 3 to 5 years so this is a LOT of fuel.

The government funded a rather large amount of research that amounted to
not much more than scientific welfare for a number of labs to look at
things like dry storage and such.  Meanwhile, private companies designed
high density racks to go in the spent fuel pits.  These racks contained
neutron absorbers between the elements so that they could be stored
closer together without any risk of criticality.  Other companies
designed stacking racks that would permit more than one layer.
Many utilities built monstrous spent fuel pits designed to hold
several cores.  The underlying assumption (or maybe hope) was that
if we could just get the Georgia White Trash out of office,
a subsequent administration would address the spent fuel issue
with something more than a ban.  Unfortunately Reagan did little to
nothing other than to spend a few hundred million on the deep
repository rot.

The problem now, from the utility side, is that even the large, dense
spent fuel pits are filling up.  And we have this rabid antinuke kook
in charge of DOE who will use similar logic Reno used to justify
killing those people at Waco to attempt to shut down the nuclear
plants.  Her argument will be that no more spent fuel can be allowed
to be generated until a "solution" is found to the problem.  What
she won't tell you is that the utilities are prohibited from finding
solutions by the still-in-effect moratorium on reprocessing.

Back to your question.  The issue isn't dillution nor is it a question
of the solution being technically difficult.  The problem is
there are hundreds of tons of fuel (each core takes about 100 tons)
sitting there in spent fuel pits.  The fuel is maybe 3-5% burned.
That means that 95% of the available uranium plus whatever plutonium
was bred is wasted.  The short term fission products are decaying
or decayed.  What remains is some Cs-137, Sr-90, Kr-85 gas, some bariums
and the actinides.  The first 4 have half-lives of 30 years or less
and so will be gone inside a century.  Thus, only short term
storage is required.  The Actinides, because they are very long lived
are low in activity and thus present little radiation hazard.
Plus they can be burned as fuel in certain kinds of reactors
as the IFR zealots on this group will tell you (and tell you and tell you
and tell you....)  The amount of actual waste produced is miniscule perhaps
a gallon per 1000 mwe-year; it is simply dispersed throughout a
huge volume valuable fuel.  Recovering all this valuable fuel and
segregating the tiny volume of "high level waste" is what
our government continues to prohibit.  Not often mentioned is the
relatively large amount of valuable inert elements produced by
the fission process.  I saw a calculation done by Westinghouse in
the late 70s that showed that the precious metals (iridium, gold, etc)
recovered from the fuel would likely pay for the processing.  These
metals are pretty far down on the fission products curve but
their high inherent value makes recovery worthwhile.  Ditto the noble
gases.  Krypton and Xenon have very high market values and demand is
high, particularly since some light bulbs are now using krypton fill and
both gases are ideal fill gases for double pane insulating glass windows.
The Xenon isotopes decay in days and the Kryptons in a few years so
simply "sipping" the gases from the spent fuel and storing it until
it decays is all that is needed.

There is no new technology needed to handle the tiny volume of high
level waste produced by reprocessing.  The French, in particular, have
refined glass vitrification, that is, sealing the waste into inert
glass.   This is just one of many known fixative methods already researched
and developed.  Though it is typically assumed that this glass
would be buried, there may be other uses such as process heat from
the heat of decay.  This high level stuff gives off a LOT of heat
and if the gamma emitters are separated, the radiation is easily
shielded.

So when you hear O'leary prattling on about how she'll have to shut
down nuclear plants because of the "waste problem", understand that
she is lying just as much as Clinton is about Whitewater gate.  Realize
too that the utilities have been paying into a fund for years to finance
waste disposal so it is NOT a matter of money.  It is simply the same
kind of lying and corruption that has marked the Clinton administration
to date.

John

Newsgroups: sci.energy
From: dietz@cs.rochester.edu (Paul Dietz)
Subject: Re: Nuclear waste disposal
Message-ID: <1994Mar10.200601.3686@cs.rochester.edu>
Date: Thu, 10 Mar 1994 20:06:01 GMT

In article <6374s_@dixie.com> jgd@dixie.com (John De Armond) writes:

 > The problem is
 > there are hundreds of tons of fuel (each core takes about 100 tons)
 > sitting there in spent fuel pits.  The fuel is maybe 3-5% burned.
 > That means that 95% of the available uranium plus whatever plutonium
 > was bred is wasted.

The 3-5% is misleading, as most of what is not burned is U-238.
Most of the U-235 that started in the fuel is burned, not wasted.


 > I saw a calculation done by Westinghouse in
 > the late 70s that showed that the precious metals (iridium, gold, etc)
 > recovered from the fuel would likely pay for the processing.  These
 > metals are pretty far down on the fission products curve but
 > their high inherent value makes recovery worthwhile.  Ditto the noble
 > gases.  Krypton and Xenon have very high market values and demand is
 > high, particularly since some light bulbs are now using krypton fill and
 > both gases are ideal fill gases for double pane insulating glass windows.
 > The Xenon isotopes decay in days and the Kryptons in a few years so
 > simply "sipping" the gases from the spent fuel and storing it until
 > it decays is all that is needed.

The yield of gold and the heavy platinum group elements (Pt, Ir, Os,
Re) should be negligible.  Rather, the economically important
(non-fuel) elements are ruthenium, rhodium and palladium.  Of these,
ruthenium is the most abundant, with about 10% of fissions leading to
a stable ruthenium nucleus.  This would be somewhere around 70 kg of
ruthenium per GW(e)-year, or about $2M of metal.  The rhodium would be
worth about 1/3 of this, the palladium much less.  I believe there is
at least one long-lived palladium radioisotope, which could make
the palladium unsaleable.

As for xenon and krypton: these sell, last I checked, for around
$3/gram and $.3/gram, respectively.  Roughly 20% of fissions should
lead to xenon, or about 180 kilograms/year -- worth about half a
million dollars per GW(e)-year.  The krypton would be laced with the
10 year halflife isotope Kr-85.  I doubt it would be economical to
store the krypton for a century or two, just so you could use it in
windows.

One would have to be careful not to saturate markets.  The current
market for xenon is only about 15 tonnes/year.  The market is growing,
however.

Whether you could reprocess 1 GW(e)-year's worth of spent fuel for a
few million dollars is not something I am competent to judge.

	Paul

Newsgroups: sci.energy
From: dietz@cs.rochester.edu (Paul Dietz)
Subject: Re: Nuclear waste disposal
Message-ID: <1994Mar11.193235.7939@cs.rochester.edu>
Date: Fri, 11 Mar 1994 19:32:35 GMT

I wrote:

> (non-fuel) elements are ruthenium, rhodium and palladium.  Of these,
> ruthenium is the most abundant, with about 10% of fissions leading to
> a stable ruthenium nucleus.  This would be somewhere around 70 kg of
> ruthenium per GW(e)-year, or about $2M of metal.

This is wrong; I got some bogus information for the price of
ruthenium.  Currently it would be less than $100/oz, or
$.2M/GW(e)-year.  Rhodium, on the other hand, is more valuable, at
least as of 1991 (> $150/gram), and so would be worth several million
dollars per GW(e)-year -- assuming not too much was destroyed by
neutron activation (its thermal neutron cross section is > 100 barns).

	Paul F. Dietz
	dietz@cs.rochester.edu