Nuclear waste is an increasingly important topic of
discussion in today’s society.
With the
advancement of nuclear science and technology, more waste has been produced and
the question regarding the placement, destruction, or reprocessing of this
waste has been debated in several countries including the
United Kingdom,
USA, and
France.
First and foremost, it is necessary to go to the source of
nuclear waste.
Most nuclear waste comes
from
nuclear power plants.
After a
certain period, most of the reactivity of the
nuclear material, usually Uranium-235, has subsided and
thus is not longer capable of producing a specific quantity of energy needed to
supply the energy market.
Nuclear power
plants supply approximately 17% of the world’s energy, and as this process is
developed, a higher percentage is imminent in the future.
Already 75% of France’s energy is produced
by nuclear reactors.
A smaller
percentage of nuclear waste comes from professional and medical institutions
that use radioactive materials for treatment and experimental purposes.
Another source of nuclear waste is from
disarmament of nuclear weapons.
Disarmament of nuclear weapons also constitutes also a major percentage
of the world’s nuclear waste produced in the world.
Nuclear Waste can be classified into two large
subcategories:
High-Level Waste (HLW)
or Low-Level Waste (LLW).
HLW’s include
spent fuel from nuclear power plants and reprocessing waste from the refinement
of nuclear materials.
HLW’s generally
include materials that that not only produce nuclides, but also heat, making
them more dangerous to store.
During
reaction in a nuclear power plant, the Uranium releases
neutrons, which collide with other Uranium atoms, stimulating them to release more neutrons and changing the atoms own atomic mass and atomic
number.
For example,
U-235 can be converted
to plutonium if one of these neutrons were to bombard it.
These substances are now classified as
transuranic elements, or heavier-than-uranium elements, which constitute most
of the long-lived nuclear waste produced by nuclear power plants.
Opposite of HLW, LLW’s include all other
types of radioactive material that is not as highly active as HLW’s.
The average LLW activity is between
0.1-2,500 curies/cubic foot.
Examples
of LLW’s include those radioactive materials from medical institutions and some
byproducts of nuclear power plants such as contaminated metals or water used in
the processing of
nuclear energy.
Furthermore, Low-Level Waste products can be further split into 4
different subcategories based on activity.
These categories are Classes A, B, C, and GTCC level waste, A being the
least active and GTCC being most active.
In regards to different longevities of radioactive materials, LLW
includes both short-lived and long-lived radionuclides.
There are some obvious problems associated with the nuclear
waste that might affect the entire world population.
It is known that decaying radioactive substances release
radiation in the form of alpha particles, beta particles, or
gamma rays.
This radiation is known to cause genetic
mutations that eventually lead to cancer.
Large doses of radiation, for instances exposure from a nuclear blast,
can cause death within a matter of days depending on the penetration levels of
the radioactivity.
If crucial cells,
mainly of the heart and brain, are affected,
cancer and death are nearly
inevitable.
Radioactivity has the
characteristic of being long-lived.
This means that even if an organism affected by radioactivity dies, another
organism that consumes the dead organism will also be affected.
From here, an entire food chain could be
affected with concentration levels increasing as you climb up the food
chain.
Currently there are issues
regarding the leakage of radioactivity from storage sites into ground water.
This “heavy” ground water, known as such
because it contains an extra neutron in one or both of the
hydrogen molecules,
can affect us directly if we drink it.
This radioactive substance can stay in our bodies and may eventually
lead to cancer.
The “heavy” ground
water can also affect us indirectly.
For instance,
phytoplankton and zooplankton would probably be the first
organisms to be affected by radioactive water.
Fish then eat these “radioactive” plankton and are also affected.
A bear then comes along and eats the
contaminated fish and is too affected by
radioactivity.
Man comes along, shoots the bear and eats
its meat.
Thus, man is also affected by
radioactivity.
In this way, it is not
only important, but crucial that we take measures in lowering radioactive
pollution but also lowering levels of nuclear waste being produced.
If the nuclear waste were targeted first,
then pollution would not be a problem.
Over the past several years, several suggestions have been
made regarding proper
disposal and storage for nuclear waste.
However, most of the efforts in the past are
expensive and require only storage of radioactive wastes, and have not solution
on actually getting rid of them.
This
is a problem because if we continue to store our waste, then storage facilities
will become full and successive generations will have to deal with this
problem.
Yet another problem to
long-term storage is ground movements and leakage.
The earth’s crust is ever changing and although storage sites are
chosen in places where geologist deem most “dormant”, this situation might
change in another 10,000 years.
If the
radioactive waste were to be leaked into the environment, there would be severe
consequence as outlined above.
Therefore,
the solution to disposal and/or storage of nuclear waste must not create solutions
for the present and problems for the future, but should create complete
solutions that will not affect the future.
It is because of the waste’s longevity that all current and past
solutions to this problem incomplete and create problems for future
generations.
Already opposition to
storage of nuclear waste has sprung from grass-roots movements, NGOs and other
environmentally concerned organizations.
However, they too do not have a solution.
Some say that we should eliminate the use of nuclear power
plants.
This measure is ridiculous
because 17% of the world’s energy is supplied by nuclear power plants, and if
we discontinue this energy source, we must find different and cost effective
energy production methods which are not available presently.
Considering that nuclear power plants
replaced coal, oil and gas power plants because it was deemed to be less
polluting and healthier for the
environment, we should not revert back to our
old methods and technology when our goal is to go to less polluting, energy
proficient ways of producing energy.
Others say that we should ban the use of radioactive substances all
together.
This too is absurd because
there are several benefits to radioactive substances such as treatment of
cancer, other medical uses such as tracers, and the advancement of the
scientific knowledge through experimentation of radioactive substances.
As you can see, radioactive substances do
have both a positive side and negative side to them.
However, because of its dangerous side effects, most people tend to
focus on the negative problems and ignore the advantagesof nuclear power.
There have been several suggestions about what should be
done about nuclear waste.
They are
listed as follows:
1)
Package the nuclear waste, put them in a
rocket, and fire it toward
the sun.
This suggestion is plausible
but extremely dangerous, unpredictable, and costly.
It is extremely dangerous because of possible flaws in the rocket's design and engineering
that might cause the rocket to explode prematurely, and because the transportation of the radioactive
chemicals is extremely dangerous.
Because of the dangers involved, not many scientific studies have been conducted to
conclude whether or not it is safe to transport and subject radioactive substances to the
extremes of space, and the reaction once the rocket crashed into the sun is entirely unknown.
This suggestion is costly because of the
amount of investment needed to finance the rockets, engineering team,
scientific experts, and
transportation costs necessary for such a project.
Because of the growing amount of nuclear
waste in the world, several rockets will have to be launched, adding more to
the cost of this project.
2)
Storage of nuclear waste in active trenches so they are
crushed and melted by the
earth’s crust movements.
Once again, this suggestion is unpredictable and also
dangerous.
It is unpredictable because
we don’t know exactly when the tectonic plates will shift pushing the waste
into the mantle.
This suggestion is
also dangerous because if one of the containers were to burst from the high
pressure, it would spread radioactive material into the sea, harming
aquatic
life and perhaps having an effect on the entire food chain.
3)
Storage of nuclear waste in geologically stable
environments.
This is what several
countries are doing at this moment.
The
United States of America has been investigating the Yucca Mountain site in
Nevada for the past decade and have deemed it a possible site for waste
storage.
In the United Kingdom,
Sellafield has storage sites as well as Thorp.
As stated earlier, this does not do anything to correct the problem, but
to put the problems aside for future generations.
4)
Reprocessing of nuclear waste/fuel.
This is also what countries are undertaking presently to minimize
the amount of waste that goes into storage.
This involves extracting uranium from nuclear waste to be reused.
Sellafield in the UK is a major reprocessing
site responsible for the refining of waste from countries such as France,
Switzerland, and Japan.
This seems to
be a good plan, however, reprocessing does not completely get rid of the waste.
The byproducts of reprocessing are still
radioactive and must be stored, again creating problems for
future generations.
5)
Stop the usage of nuclear fuel and building of nuclear
weaponry.
Although stopping the
advancement of nuclear weaponry would benefit all of man, stopping the usage of
nuclear fuel as a source of energy is not beneficial at the present time.
If a new method of energy production were to
be discovered, possibly
cold fusion between
deuterium molecules or nitrogen
based fuel sources, then it would be imaginable that we could scrap the use of
uranium and plutonium as energy supplies.
However, through years of research, it has been proven that by splitting
the bonds inside the atom, a huge amount of energy can be extracted and
processed, so it would seem that our best fuel source in terms of power
production and efficiency, is nuclear power.
In conclusion, although we have greatly benefited from the
advancement of nuclear science, we are also subjected to a great burden that we
must remove before it gets too late.
A
clean, reliable, and pragmatic method of waste removal, storage, and/or
destruction must be implemented; however, science and research have proved to
be futile in this field of science.
Perhaps in the future, a new and innovative method of waste destruction
will be created.
But for now, efforts
must go on in either finding a new way of efficiently producing energy for the
mass market.
Already, research has gone
into nuclear fusion, as opposed to fission, which leaves almost no harmful
byproducts and releases a huge amount of energy.
Hopefully, we can propose a better solution than storage for
nuclear waste in the future.
Source: J.Sy; British School in the Netherlands