fusion

storage areas. Only about 4 percent of this fuel, 176 metric
tons, is HLW that would be separated out during reprocessing.
By the year 2000, more than 98,000 metric tons
of spent fuel is expected, with about 3,920 metric tons of
this as HLW.
In addition, the amount of reprocessed HLW currently
in the United States consists of approximately 70 million
gallons from the Department of Defense and only 0.6
million gallons from the one commercial U.S. reprocessing
plant, the now-closed facility at West Valley, New York.
Reprocessing fuel and separating out the waste will reduce
by more than 25 times the quantity of waste material that
must be disposed of. This, combined with the reduced
radioactivity and heat generation, is an additional important
advantage of a fuel reprocessing system.
Storage Technology
There are two technical problems in handling and
storing radioactive nuclear fission waste material. The first
is the radioactivity from the decay of unstable elements
by either alpha or beta particles and gamma rays. This
radiation is dangerous to human beings from external or
internal sources; therefore, it must be kept isolated from
the biosphere for as long as the activity remains high.
The second problem is that radioactive decay produces
energy in the orm of heat, and this heat must be dissipated
for as long a time period required in order to keep
material temperatures below certain design limits. Both
the shielding ind the heat removal must be resolved
simultaneously,
The most technically developed process for high-level
waste disposal 5 to store the waste in concentrated liquid
form at ground level for a cooling period of 5 to 10 years.
At that point it can be solidified into small canisters and
buried in a de^p underground location in thick, stable
rock-salt strata. Liquid storage of the waste and eventual
solidification al will take place on the reprocessing plant
site (for examf le, the Barnwell facility) in a completely
controlled and monitored environment. For years storage
of liquid wastes has been a state-of-the-art technology. In
fact, the Depar ment of Defense has used storage in this
form since the early 1940s and has highly developed the
technique (Figure 2).
This propose I solidification process uses an automated
system that cor verts the liquid waste by evaporation to a
fine powder, rrixes it with a fine glassy frit material, and
converts it to a olid glassy cylinder by heating the mixture
to melting and hen solidifying it (Figure 3). This is already
a developed te< hnology and is now used commercially in
France, as sho vn in the photograph. The solid waste
What the Experts Say
About Radioactive
Nuclear Waste
American Institute of Chemical Engineers,
Nuclear Engineering Division
policy statement, 1977:
". . . Satisfactory techniques exist
today for safe radioactive materials
handling, the reprocessing of spent
fuel, and solidification of high-level
wastes. . . . Several candidate options
for ultimate disposal are ready for
demonstration. These techniques are
being improved rapidly as the technology
continues to advance. Other
countries have recognized this, and
have overtaken the United States in
the rate of introduction of efficient
nuclear power plants and waste treatment
techniques. . . . The Institute
believes that actual demonstration of
radioactive waste disposal is sufficiently
urgent that it is far better to
proceed with an acceptable solution
than to delay by looking for unnecessary
minor benefits which might
possibly emerge from alternatives.
. . ."
wastes disposal at the earliest possible
time, as a part of a national nuclear
waste disposal program. . . ."
American Physical Society, study on
Nuclear Fuel Cycles and Waste Management,
published in Reviews of
Modern Physics, 1978:
". . . The technology exists for recoverable
storage of the spent fuel
with minimal deterioration to preserve
the associated resources, but
full-scale demonstration is required
before use. . . .
"Effective long-term isolation for
spent fuel, high-level or transuranic
waste can be achieved by geologic
emplacement. A waste repository can
be developed in accord with appropriate
site selection criteria that would
ensure low probability that erosion,
volcanism, meteorite impact and
other natural events could breach the
repository. . . ."
Association for Cooperation in Engineering,
Coordinating Committee on
Energy (This association represents 24
major engineering professional societies
in the United States, with a combined
membership of more than
700,000 engineers.), 1980:
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August 198(
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