Over the last couple of months, there has been a lot of talk
about finally doing something with the spent fuel inventory that is steadily
increasing on site at our nuclear reactors.
The problem is, there is no solution to permanently dispose of this
waste, and there is no realistic technology available to even render it less
dangerous. It simply must be isolated
from the environment.
Spent fuel is the “used up” fuel from a nuclear
reactor. A fresh fuel rod contains 97%
Uranium 238, and 3% U235 (the fissionable form of Uranium.) After about 2 years of use in a reactor, it
is “spent,” and now has a composition of about 96% Uranium 238, 1% U235, 1%
Plutonium 239 (which is created by neutron capture of U238), and 2-3% fission
products (formed when U235 fissions.)
The fuel rods are typically removed and stored in a pool to keep them
cool, and provide shielding from the high levels of radioactivity that they
emit. Hence, it is called high-level
waste. After about five years, the fuel
has somewhat stabilized with many of the fission products having decayed; but
the remaining ones, as well as the Plutonium, remain highly radioactive for
many thousands of years. This material
needs to be contained and shielded, and continues to give off heat as a
byproduct of its radioactive decay.
There is about 70,000 tons of spent fuel stored at reactor
sites in the U.S., and utilities are running out of room in their fuel pools as
they keep adding to the volume. Many
are opting to place these fuel bundles into dry-cask storage…large heavily
shielded canisters that typically sit on a pad outside, and are
air-cooled. At Humboldt Bay, there are
6 casks, and it cost close to $70 million to put the fuel into dry
storage. It costs about $12
million/year for security, monitoring, and maintenance. It is estimated that we would need some
6000+ casks to contain our current spent fuel inventory. $80 billion + ??? in today’s dollars.
Nuclear fuel is owned by the government’s Department of Energy,
and it is “rented” out to nuclear utilities.
The 1982 Nuclear Waste Policy Act mandated that by 1998, the government
would have a deep geologic repository ready, and would take possession of the
spent fuel. This has not happened…not
even close. Many years, and $15 billion
have been spent on Yucca Mountain, a possible repository site north of Las
Vegas. Aside from all the politics, the
bottom line is that the DOE could not meet the EPA criteria and standards for
containment of radioactivity at this site.
This isolation from the environment needs to be for a minimum of 10,000
years, even though radioactivity will remain there for 100,000 years or
more. The sealed central storage of so
much radioactivity would produce high amounts of heat that would unpredictably
create changes in the geology of the mountain, and threaten the integrity of
the casks themselves. Cask failure
could lead to the release and mixing of fuel that could trigger fission
processes, explosions, contamination of ground water, and a host of other
unknown reactions during the thousands of years this material is active. Allison MacFarlane (the new chairwoman of
the Nuclear Regulatory Commission, and a noted geologist) concludes the obvious
in her excellent book “Uncertainty Underground.” We do not know enough to be able to model and predict what will
happen so many years into the future.
The recent push by the nuclear industry, wanting to rid
themselves of the responsibility of spent fuel, is pushing for a new
“independent” review of Yucca Mountain.
President Obama’s Blue Ribbon Committee of a few years ago came to the
conclusion that there is no solution to this waste problem. Congress will now form another committee to
“come up with a solution.” This is not
a political problem. It is the
scientific reality that radioactivity is an atomic-level process, and not a
molecular one that can be manipulated and neutralized. We cannot make it go away. The early nuclear pioneers understood this,
but in the glory days of nuclear bombs and “electricity too cheap to meter,”
they rushed ahead hoping that someday, someone would figure it out. 70 years down the road, we don’t even have a
clue. Oh, what to do?
There are several possible courses of action, which will be
looked at and proposed over the next couple of years. The first is to continue characterizing Yucca Mountain or finding
some other geologic site somewhere…Texas, New Mexico, Mississippi ??? We are not alone, since other countries are
also beginning to look at solutions for their wastes. Sweden, with its relatively small amount of spent fuel, is
currently storing it in copper casks in a geologic cave, with the idea that it
can be retrieved when a better solution is found. Problems have already begun to surface. Germany has recently reopened their investigations, going back to the drawing board. Japan doesn’t have a clue with what they are
going to do…right now they’re “underwater.”
A second option is an idea that has been around for a while
and involves creating a central Monitored Retrievable Site. Take all the casks, and ship them to one
location. The leading contender is
Skull Mountain in Utah, where the 35 members of the Goshute Indian Rancheria
were offered $50 million to use a portion of their land for this purpose. Too bad it is directly in the flight path of
an Air Force practice bombing range!
Placing all this material in one place is very risky, especially with
current terrorist and climate change possibilities. Transporting 6000+ casks and storing them in the open
air…???!!! And then transporting them
again if/when a repository is built, or maintaining/re-casking the spent fuel
50-60 years down the road?
Security? Very expensive and
dangerous.
A third option, which the nuclear industry wants, is
probably more insane than the initial creation of the entire nuclear power
business. Reprocessing, or recycling as
they call it, involves taking the fuel rods, grinding them up and dissolving
them in acids, and then separating out the U238, the unused U235, and the
Plutonium, which would then be put into new fuel. This is what was done in Hanford to acquire the Plutonium for our
nuclear bombs. The remaining liquids, containing the highly radioactive fission
products, would then be concentrated, and “vitrified”…converted into a
glass/ceramic log that will have to be disposed of in a geologic repository for
thousands of years. Sounds great? Ed Lyman, a prominent scientist with the
Union of Concerned Scientists says
“reprocessing actually increases, not decreases, the total volume of long-lived
nuclear waste that must be stored and eventually buried in a geologic
repository It only slightly reduces the volume of high-level nuclear
waste that must be disposed of in a repository.” Can we really do this? At
what cost? The “new” vitrification
plant under construction at Hanford is half completed, 12 years behind
schedule, and 13X over budget at a current $13 billion. How many of these
plants would we have to build, and where?
How would we be transporting all this dangerous material around? We’d have to build new power plants to burn
the “new” mixed-oxide fuel and Plutonium fuel?
How much would it cost to build this whole new infrastructure? We tried this in West Valley, New York back
in the 70’s and it turned into an economic and environmental disaster.
Reprocessing produces more problems that it can solve. It hasn’t worked for England, Germany, and
Japan. The French are reprocessing for
the Japanese, and are nowhere near dealing with their own spent fuel. We don’t know much about the Russian
program, but are very concerned with the possibility of Iran and North Korea
developing the process to build nuclear weapons. The bottom line is that
reprocessing would be a very, very expensive proposition that the taxpayer
would wind up funding. Hundreds of
billions of dollars.
There are other options out there…putting it in rockets and
shooting it into the sun, dumping it in the deep sea trenches, drilling a deep
hole into the earth’s crust and dropping the canisters down. The most recent moronic idea comes from the
chairman of the Oregon Republican Party…”sprinkle nuclear waste over the oceans
from airplanes…”
The best strategy seems to be to place spent fuel in
dry-cask storage, and keep that material on site until a better solution comes
up…which may be never, meaning that the 30+ nuclear sites would become defacto
waste dumps. At least the casks can be
monitored, maintained, and repaired if need be. There are several sites, such as California’s Humboldt Bay,
Diablo Canyon, and San Onofre, where special safety issues such as earthquake, tsunami, and flooding,
might require moving these casks to a more secure location.
Whatever we decide to do, it will be very EXPENSIVE for a
very long time.
Some source material:
And then, there is Low-Level Radioactive Wastes…a whole
other story:
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