Nuclear Waste Disposal

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L11
ETHICAL IMPLICATIONS OF NUCLEAR POWER AND COAL IN THE
APPALACHIAN MOUNTAINS
Claire Gillman (cdg31@pitt.edu)
INTRODUCTION: THE RISE OF NUCLEAR
POWER IN COAL COUNTRY
As the world’s population passes seven billion and
countries continue to develop new technology and
infrastructure at a rapid rate, the need for a clean, renewable
energy source that is efficient and safe grows larger. In the
United States alone, the Department of Energy has forecast
that domestic electricity demand will increase 30% in the
next 25 years [1]. Out of the many options for sustainable
energy such as solar power, wind turbines and geothermal
technology, nuclear power stands out. Nuclear power plants
do not require large amounts of space or rely on the weather
like solar power, and they produce more megawatts of
electricity per dollar than any other kind of clean energy
source [1].
I am a lead nuclear engineer at Westinghouse, a large
company that designs plants and fabricates parts for many
types of nuclear reactors, including nuclear power plants. As
nuclear power becomes a more popular energy source
around the world, our nuclear engineering sector has
experienced huge growth. Recently, Westinghouse has
expressed strong interest in a contract to build a large
pressurized water nuclear power plant in West Virginia, an
area that has historically been very active in the mining of
coal for the purpose of making electricity. This would be a
multi-million dollar, long-term project for the company that
would bring carbon-free electricity to thousands of homes
throughout the Appalachian Mountains and would also
significantly reduce the region’s dependency on coal. In the
past decade, West Virginia and Kentucky have supplied
more than 20% of coal mined in the United States [2]. Coal
mining was and still is an integral part of the culture and
history of West Virginia, but it is also needlessly destructive
to the environment and local communities. As the
production of nuclear power is carbon free, it is a more
sustainable practice than the surface mining that is currently
practiced in the region. However, nuclear power produces
radioactive waste that has to be stored for thousands of
years, and there is currently no perfect solution for storage or
disposal [3]. Both options affect the environment in different
ways. As a nuclear engineer, it is my job to not only help
with the development of new energy technologies but also to
consider the ethical implications of my actions and how they
affect the rest of the world.
MOUNTAINTOP REMOVAL MINING
University of Pittsburgh, Swanson School of Engineering 1
Submission Date 2013-10-29
The primary method of coal mining in Appalachia is
mountaintop removal mining (MTR), where the coal seams
are mined by removing the land that covers the seam,
effectively leveling the existing mountains [2]. After
removing the coal, excess rock is dumped back onto the site
of the former mountain or, as happens more frequently,
deposited in nearby valleys and streams, called “valley fills”
[2]. The environmental and community health effects of
MTR in the Appalachian region have been extensively
studied over the past 30 years. The general scientific
consensus is that MTR has a myriad of negative
environmental effects including but not limited to habitat
destruction, deforestation, decreases in biodiversity, poor
water quality and increases in airborne pollution [4]. Surface
mining has also been linked to increased rates of cancer,
depression, birth defects and respiratory diseases in mining
communities [4]. The installation of this multi-reactor
nuclear power plant would provide carbon-free power to
thousands of residents and businesses in the area,
significantly reducing the need for destructive MTR surface
mining.
ETHICAL DILEMMAS
However, there are two ethical dilemmas that the
construction of this power plant will bring up. First,
presently there is no perfect waste management solution to
dispose of the radioactive spent fuel rods and used uranium
that are produced as a part of the nuclear reaction cycle.
These rods remain radioactive and harmful to the
environment for thousands of years, and have to be stored
somewhere in order to not pose a threat to humans, animals
or the water supply. Since the rise of nuclear power in the
1960s, nuclear engineers and scientists have examined many
possible storage solutions for high level radioactive waste,
including but not limited to outer space disposal on
satellites, ocean floor disposal, synthetic concretes, storage
inside the Earth’s crust, and geologic storage sites in
mountains or cliffs [5]. The most viable of these options are
deep geologic disposal at sites like Yucca Mountain,
Nevada, where the waste is stored deep underground in
controlled environments, and deep borehole disposal, where
the radioactive material is injected into kilometers-deep
wells which are then sealed with rock and cement [5].
Currently, spent radioactive material from power plants is
kept in large concrete-and-steel dry casks that are filled with
inert gas and sealed to prevent leaks [1]. While dry cask
storage does not pose an immediate environmental threat, it
is not a long-term solution that will allow nuclear power to
become a globally accepted “green” energy source.
Claire Gillman
One of the biggest concerns that comes with the use of
any nuclear technology is radioactivity and its effects on
people and the environment. As shown by the 1986
Chernobyl disaster in Ukraine, where wide swaths of land
still lay abandoned and uninhabited because of the high
levels of radioactivity more than 25 years after the accident,
fallout from nuclear power plants can have a permanent,
measured effect on its surroundings if it is not properly
stored and managed [3]. For this reason, many leading
nuclear experts believe that underground storage at geologic
sites in mountains or underground is one of the most viable
current options for nuclear waste disposal.
the radioactive material and then sealed up. Opponents of
geological disposal at Yucca Mountain argue that the
nuclear waste is not significantly contained in geological
sites because it is still relatively close to the surface and
therefore poses a risk to communities [1]. With deep
borehole disposal, this risk to humans is significantly
reduced because the holes would be drilled to a depth of two
kilometers or more, putting more than a mile of the Earth’s
crust between the fuel rods and human habitation and
isolating the waste in case of any leaks or spills [8]. The U.S.
Nuclear Waste Technical Review Board, a government
regulatory agency that oversees nuclear power production
facilities, predicts “each borehole could hold between 100
and 200 metric tons (MT) spent nuclear fuel (SNF), so 10 to
20 boreholes could contain the approximately 2,000 MT
SNF discharged from U.S. nuclear power plants each
year”[8]. In addition to large storage capacity, multiple
locations throughout the US have the appropriate geological
foundation for borehole drilling, making site scouting less
difficult than it is for geological repositories [1].
Borehole disposal’s relatively small geographic footprint
and isolation from human activity make it an attractive
solution to the nuclear waste problem, but significant
engineering challenges do exist. Current drilling technology
for very deep holes is still in the early stages and can be slow
and expensive [5]. In addition, more research and
engineering is required to develop an appropriately robust
borehole seal that will isolate the radioactive material from
pressure
changes,
extreme
temperature,
weather,
earthquakes and other geological events [8]. Regardless,
deep borehole disposal shows potential as a viable storage
option for the US and other countries in the near future.
Because these storage technologies are not perfect, nuclear
engineers must always consider the risk of failure, and what
could happen.
WASTE DISPOSAL TECHNOLOGIES
Geological Repositories
The main goal of deep geological repositories is to
contain nuclear waste in a stable, isolated area that will not
be disturbed by human activities or natural disasters for the
foreseeable future. The spent fuel rods are first placed in
canisters made of cast iron and copper to prevent corrosion
and leakage [5]. The canisters are then surrounded by a rock
and synthetic clay buffer to separate the groundwater around
the storage site from any potential radioactive contamination
[6]. Scientists are currently searching for the optimal mix of
buffer ingredients that will protect the canisters from
pressure changes, high temperatures, flooding and other
random events that could compromise the security of the
waste storage site [3].
In the United States, one potential nuclear waste
repository site is Yucca Mountain, Nevada, located in the
Mojave Desert outside of Law Vegas. The repository would
consist of a network of storage tunnels 300 m below the
surface and 300 m above the water table to avoid
contamination [6]. About the Nevada site, director of the
Nuclear Regulatory Commission’s Three Mile Island
Cleanup Site Office Lake H. Barrett says: “Built in volcanic
rock high above the water table and accessed by gently
inclined ramps from the ridge slopes, a Yucca Mountain
repository would be ideally situated to serve for monitored
geologic storage of spent fuel, which ultimately could be
retrieved if, say, fuel recycling should become economically
attractive” [7].
Since 1987 when the site was chosen for consideration,
Yucca Mountain has been extensively studied as a potential
site for nuclear waste storage, with teams of geologists,
nuclear engineers, environmental engineers and chemists
examining every inch of the site for potential risks [6].
However, the government put the project on hold in 2010
and no progress has been made since [7].
THE ETHICS OF NUCLEAR POWER AND
THE ENVIRONMENT
While carbon-free nuclear power would be replacing a
comparatively less environmentally conscious technology
(MTR coal mining), nuclear power still has an effect on the
environment that needs to be taken into account when
deciding the ethicality of building the power plant. In the
National Society of Professional Engineers (NSPE) Code of
Ethics, it states that “Engineers shall at all times strive to
serve the public interest” and "Engineers are encouraged to
adhere to the principles of sustainable development in order
to protect the environment for future generations” [9]. In
light of the health problems caused by coal mining, I believe
that attempting to reduce reliance on coal through the use of
alternative sources qualifies as serving the public interest.
While nuclear power has its own set of inherent risks,
including the safe disposal of radioactive fuel, to me the
benefits of cleaner energy and reduced carbon emissions
Deep Borehole Disposal
An alternative but significantly less well-developed waste
containment technology is deep borehole disposal, in which
well-like holes are drilled into the Earth’s crust to contain
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Claire Gillman
outweigh the risks and therefore help serve the public
interest. In addition, the Code of Ethics of the American
Nuclear Society, a nonprofit open to nuclear scientists,
engineers and educators, states that engineers should “work
to protect the environment,” which implies that engineers
have an obligation toward sustainability [10]. Despite the
environmental hazards of working with radioactive
substances, I believe that it is a far more sustainable energy
source than the practice of mountaintop removal mining.
Waste disposal technology is rapidly improving as nuclear
power grows in countries like India, and as the technology
for containing radioactive material improves, arguments
against nuclear power diminish. In recent years, many
scientists and engineers have been arguing that social justice
and sustainability should be included in the list of
professional obligations of an engineer [11]. Based on these
ethical codes and data about nuclear reactors and the effect
of surface mining on the Appalachian region, I believe it is
ethical to continue with the construction of the power plant.
[5]J. Kim, S. Kwon, M. Sanchez, G. Cho. (16 February
2011). “Geological Disposal of High Level Nuclear Waste.”
KSCE Journal of Civil Engineering. (Online article). DOI:
10.1007/s12205-011-0012-8. 721-737
[6]N. Chapman, A. Hooper. (17 October 2011). “The
disposal of radioactive wastes underground.” Proceedings of
the Geologists' Association. (Online article). DOI:
10.1016/j.pgeola.2011.10.001. 46-63.
[7] L. Barrett, L. Carter, K. Rogers. (Fall 2010). “Nuclear
waste disposal showdown at Yucca Mountain.” Issues in
Science and Technology. (Online article). URL:
http://go.galegroup.com/ps/i.do?id=GALE%7CA240623034
&v=2.1&u=upitt_main&it=r&p=AONE&sw=w&asid=01e7
238a022c36ae85621dfe99334748. 80.
[8]“Deep Borehole Disposal of Spent Nuclear Fuel and
High-Level Waste.” U.S. Nuclear Waste Technical Review
Board. (Online report). URL:
http://www.nwtrb.gov/facts/BoreholeFactSheet.pdf. 1-3.
CONCLUSION: PROMOTING PUBLIC
WELFARE THROUGH NUCLEAR
ENGINEERING
[9] “NSPE Code of Ethics for Engineers.” National Society
of Professional Engineers. (2007). Webpage.
http://www.nspe.org/Ethics/CodeofEthics/index.html
Determining ethical actions in situations involving
nuclear power is a complicated affair and engineers must
take into account many different factors including impact on
the environment, people, and the economy [12]. As an
engineer, I feel I have an obligation to promote the welfare
of the public and to advance scientific discovery in my field
[11]. After examining the consequences of coal mining in
West Virginia and the pros and cons of various nuclear
waste disposal methods, I have determined that the most
ethical course of action is to build the nuclear power plant.
[10] “Code of Ethics.” American Nuclear Society. (2003).
Webpage. http://www.ans.org/about/coe/
[11] D. Michelfelder, S. Jones. (2011). “Sustaining
Engineering Codes of Ethics for the Twenty First Century.”
Science and Engineering Ethics. (Online article). DOI:
10.1007/s11948-011-9310-2
[12] W. Abulfaraj, M. Hassan. (2007). “The Teaching and
Assessment of Professional Ethics in the Nuclear
Engineering Education According to ABET Engineering
Criteria.” American Society for Engineering Education.
REFERENCES
[1] M. Schaffer. (6 December 2010). “Toward a viable
nuclear waste disposal program.” Energy Policy. (Online
article). DOI: /10.1016/j.enpol.2010.12.010. 1382-1388.
ACKNOWLEDGEMENTS
I would like to thank my peer advisor Becca Schaefer for
giving me some wisdom about this assignment, and my
roommate Kim Dickinson for helping me look for typos. I
would also like to thank the librarians at Hillman Library
who assisted me in accessing online databases, and my
writing instructor Dan Mcmillan for his constructive
comments on my previous writing assignment that helped
me craft this paper.
[2] J. Amos, W.Galloway. (2013). “The Overlooked
Terrestrial Impacts of Mountaintop Mining.” Bioscience.
(Online article). DOI: 10.1525/bio.2013.63.5.7
[3] “Backgrounder on Chernobyl Nuclear Power Plant
Accident.” (20 June 2013). United States Nuclear
Regulatory Commission. (Web page). URL:
www.nrc.gov/reading-rm/doc-collections/factsheets/chernobyl-bg.html
[4] M.A. Palmer, E. Bernhardt. (2010). “Mountaintop
Mining Consequences.” Science. (Online article). DOI:
10.1126/science.118054
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