Schaub, 4:00
Group R03
MINING THE OCEANS: URANIUM EXTRACTION FROM SEAWATER
Caren Dieglio (ctd9@pitt.edu)
seems futile to not explore the extraction of uranium from
seawater.
THE AQUEOUS SOLUTION
Putting the World’s Oceans to Work
CURRENT URANIUM MINING METHODS
In today’s society, sustainability is widely emphasized
and encouraged. Yet, we are not fully utilizing one of
Earth’s most plentiful resources: seawater. Despite the
unfortunate fact that the abundance of seawater cannot be
used for drinking, the oceans teem with other uses. One of
the possibilities seawater has to offer lies in its abundance of
uranium.
Uranium is a mineral instrumental to the nuclear energy
industry that plays a vital role in electricity production.
However, traditional methods of uranium mining wreak
havoc on the environment and pose potential dangers to
public health: two matters that should be of concern to
everyone. The American Institute of Chemical Engineers
(AIChE), American Nuclear Society (ANS), and National
Society of Professional Engineers (NSPE) Codes of Ethics
reinforce that these health and environmental concerns are of
great importance to and prominent consideration of
engineers. Engineers have recently increased attention
towards extracting uranium from seawater, a preferable
alternative to previously-used methods of extraction.
Developments in adsorbent materials as well as the simple,
yet inventive, study of manufacturing shrimp shells into
absorbing mats have presented promising advances in the
field of uranium extraction from seawater.
The advancements in seawater extraction made by
engineers uphold the various Codes of Ethics and serve as
examples of innovation in engineering. These innovative
examples inspire engineering students and serve as a
connection between students’ studies and real-world
applications. Research into current engineering issues is
essential to engineering education because it forces students
to consider both the practical and ethical role of engineering
in society.
As a future engineer, I am called by the Codes of Ethics
to utilize my engineering position to promote sustainability
and public welfare. Additionally, I am compelled to act
according to the Codes of Ethics because I plan to be both an
innovative and ethical engineer. My hope for my future as
an engineer leads me to support ethical methods of uranium
extraction that protect public health and protect the
environment. I consider the antiquated uranium mining
techniques a threat to the environment and society and assert
that today’s engineers personify their Codes of Ethics and
seriously consider alternative methods of extraction. And
with a resource that covers 71% of the Earth’s surface [1], it
Open Pit and Underground Mining Produce Toxic Waste
Material
There are four main types of uranium mining: open pit,
underground, heap leaching, and in-situ leaching [2]. All
four methods pose great risks to society and the
environment. Arguably, uranium mining techniques are
very similar to the mining of other minerals, yet the
radioactive nature and byproducts of uranium pose an
elevated threat to both the environment and public health. In
open pit mining, a practice in which overburden, the rock
and earth above uranium ores, is removed by heavy drilling,
waste rock is produced. This waste rock often contains
uranium that is too low of a grade for processing and always
contains toxic byproducts. The waste rock is left as, quite
appropriately, waste after mining is completed and, due to
the presence of stagnant byproducts and uranium in the rock,
can “release radon gas and seepage water containing
radioactive and toxic materials” [2]. Dr. Gordon Edwards of
the Canadian Coalition on Nuclear Responsibility reveals
that 85% of toxic materials, which have half-lives of
hundreds of thousands of years, are left behind by mining
companies to endanger the public and environment [3].
Underground mining is a method employed in the
mining of other minerals, yet underground uranium mining
exposes miners to radon gas, a seriously toxic byproduct that
can lead to lung cancer [4]. In addition, though it seems
underground mining creates little disturbance to the drilling
site and surrounding area, the excavation process introduces
pollution in the form of waste rock. In the “cut and fill”
method, waste rock is used to fill the space left empty after
the removal of uranium ore, thus allowing the release of
poisonous radon gas and the pollution of groundwater that
occurs during open pit mining.
In the “shrinkage”
technique, only the ore that is economically useful is
removed and the remaining rock is blasted away, leaving a
large crater in the earth [4]. This crater alters the terrain and
creates difficulties of habitation for wildlife that had
previously occupied the mining site.
Open pit and
underground mining are practices that threaten workers’
health and disrupt the environment, yet heap and in-situ
leaching are seemingly less intrusive methods that introduce
even more dangerous side effects.
University of Pittsburgh, Swanson School of Engineering
October 30, 2012
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Caren Dieglio
public health that are threatened by terrestrial mining
techniques.
The possibility of a better method of uranium extraction
is important to me as a future engineer because it provides
the opportunity for me to expand upon and even improve the
mining of a mineral that powers nuclear energy: an industry
that will assuredly be very prominent in my time as a
practicing engineer. The use of the ocean for uranium
extraction is a sustainable mining method that answers
environmental concerns. If a viable method of seawater
extraction is engineered that reduces the current elevated
cost of extraction, uranium uptake from seawater would
eradicate the environmental and health risks of terrestrial
mining and alleviate the current economic stress of seawater
extraction. Because this would be significant progress in the
field of engineering, I, as a future engineer planning to
perform my work ethically, fully support the effort to mine
uranium from seawater. Recent advances have been made in
methods of uranium extraction from seawater and should
continue to be actively pursued in order to create a more
economical and environmentally-friendly extraction
technique.
Leaching Provides Direct Contact with Groundwater
In heap leaching, the land at the mining site is leveled
and then covered in plastic, atop which uranium ore is piled.
A chemical, often sulfuric acid, is then sprayed on the ore to
extract the uranium.
This produces radon gas and
contaminated runoff that can pollute groundwater with
radioactive material.
Radioactivity can cause drastic
sicknesses in humans, including nausea, vomiting, burns,
and cancer [5]. This radioactive contamination can continue
after the mining site has been closed [2]. Similar to heap
leaching, in-situ leaching utilizes a chemical agent for
uranium extraction, yet one that is pumped directly into the
ground. This allows direct contact between the chemical
agent and groundwater and also creates an “impossibility of
restoring natural conditions in the leaching zone” [2]. This
“impossibility” of restoration is due to the fact that the
leaching zone is polluted with radioactive byproducts that
pose the aforementioned dangers to public health and, as
verified by Dr. Gordon Edwards, have half-lives of hundreds
of thousands of years. The current practice of uranium
mining creates evident dangers for the environment and
health of the community, thus making a more
environmentally-sound method of uranium extraction
necessary.
Studies Show Seawater Extraction can be
Economically-Favorable
Within the past decade, numerous lab groups and energy
companies have turned their attention to creating materials
that reduce the cost of extracting uranium from seawater.
The movement began in 1999 when the Japan Atomic
Energy Agency team prepared a sorbent of “nonwoven
sheets of amidoxime-functionalized polymer” that they
stacked into three large cages and then lowered into the
Pacific Ocean [6]. The setup extracted .5g of uranium per
kg of sorbent in 30 days. Wishing to cut costs and increase
extraction, the Japanese company created seaweed-like
braids of the sorbent and lowered them to the ocean floor via
anchors. This method tripled their extraction, producing
1.5g of uranium per kg of sorbent [6].
This increased extraction was a major breakthrough and
prompted scientists to perform extensive research into the
amidoxime-polymer materials used in making the adsorbents
and the agents used to leach the uranium. University of
Idaho professor Chien M. Wai has been studying the use of
supercritical CO2 in place of acids to leach uranium because
the acids erode the sorbents and decrease their lifetime [6].
At the University of Alabama, chemistry professor Robin
Rogers has proposed a very interesting substitute to the
polymer fibers that comprise the sorbents. Rogers and his
team discovered that a molten salt could extract chitin, an
important polymer, from crustacean shells. This chitin could
then be “electrospun” into fibers that can be made into mats
used to extract uranium [7]. Rogers pointed out that this is a
very attractive alternative because, when the mats break
down, “We’d be putting back into the ocean something that
comes from the ocean and is biodegradable” [8].
THE CALL OF THE SEA
Uranium Extraction from Seawater Receives Increased
Attention
The solution to the environmentally-hazardous uranium
mining that is currently in practice lies in extracting uranium
from seawater. According to Benjamin P. Hay, a scientist at
Oak Ridge National Laboratory, a site that has been working
extensively on this project, “It’s estimated that more than 4
billion metric tons of uranium are dissolved in the Earth’s
oceans” [6]. That is about 1000 times more uranium than
what is found in terrestrial sources [6]. So, why have
scientists not tapped into this abundance of uranium,
especially as the nuclear power industry swiftly expands?
The answer is simple: expense. Though seawater contains a
large amount of uranium, the concentration is very dilute
and marine conditions often create challenges to extracting
the uranium [6].
The concentration of uranium in seawater is 3.3mg per
cubic meter [6]. This miniscule amount creates a large gap
between the expense of extracting uranium and the profit
gained at current market prices for uranium. Nevertheless,
with the overabundance of uranium present in seawater, it is
well worth the effort of scientists and engineers to research
new, innovative ways to “mine” the oceans for uranium
because there is a possibility to protect the environment and
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Caren Dieglio
Finally, the most impressive advancement made in the
transition from terrestrial mining to seawater extraction was
at the Oak Ridge National Laboratory in collaboration with
Hills Inc. in Florida. The two companies have created a new
adsorbent called HiCap, “a material that can rapidly,
selectively, and economically extract valuable and precious
dissolved metals from water” [8]. Chris Janke of ORNL
claims, “Our adsorbents can extract 5 to 7 times more
uranium at uptake rates 7 times faster than the world’s best
adsorbents” [8]. At 3.4g of uranium per kg of sorbent, Janke
may be exaggerating HiCap’s superiority over other
adsorbents, yet this is still a major improvement in the
amount of uranium extracted, thus helping to close the fiscal
gap between cost and profit of extraction [7]. A recent
analysis by University of Texas mechanical engineering
professor Erich A. Schneider found that the new methods of
uranium extraction cost about $600 per kg: a significant
decrease from the previous cost of $1200 per kg [6]. The
research conducted by these scientists has resulted in
adsorbents that reduce the cost of extraction and could open
the door to seawater extraction serving as the most economic
and environmentally-conscious method of uranium mining.
uranium only after the sorbents have been removed from the
oceans and placed in a secure mining facility [6].
Uranium extraction from seawater creates another use for
one of the most abundant natural resources. I have always
considered it to be a shame that seawater cannot be used for
drinking, but uranium extraction from seawater presents a
new possibility from the oceans. The oceans may not offer
energy to our bodies through water, but they can now
provide a source of nuclear energy to keep our electricity on,
our industries running, and our medical devices up to speed.
Extraction of uranium from seawater solves the
environmental and health problems of terrestrial mining and
serves to power an energy industry upon which much of
society is dependent. Now, we must encourage the science
and engineering community to continue the efforts to find an
economically-favorable method of extraction.
ETHICAL CONSIDERATIONS PROVIDE
ADDITIONAL INCENTIVE FOR A SHIFT
FROM TERRESTRIAL MINING TO
SEAWATER EXTRACTION
Codes of Ethics Urge Engineers to Take Action
PROMISING FUTURE FOR URANIUM
EXTRACTION FROM SEAWATER
A portion of the incentive to develop a more reliable
method of uranium extraction from seawater is
economically-based and seeks to maximize profit, yet this
study is partially driven by ethical responsibility as well.
Environmental and health hazards, such as those created by
terrestrial uranium mining, should be of concern to all
people and are of the utmost interest to engineers because
they are equipped with the tools and knowledge to alter
these dangerous practices. Thus, engineers are rightfully
called by the National Society of Professional Engineers
Code of Ethics and by the various engineering disciplines’
Codes of Ethics to utilize their positions as engineers to
rectify any ethical violations.
The case of uranium mining applies directly to chemical
and nuclear engineering; disciplines whose Codes of Ethics
both necessitate that the engineers involved in uranium
mining perform their duties in a manner that is beneficial to
society, health, and the environment. The engineers
exploring and crafting the new tools for uranium extraction
from seawater are held accountable to the NSPE Code of
Ethics as well, whose first fundamental canon asserts all
engineers must “hold paramount the safety, health, and
welfare of the public” [9]. Both the American Institute of
Chemical Engineers and the American Nuclear Society
Codes of Ethics reinforce this concern for public welfare,
but also include that engineers are to “protect the
environment in performance of their professional duties”
[10]. The engineering Codes of Ethics are consistent with
my position that the welfare of the public and environment
are of greater importance than gaining a profit from uranium
mining. Public safety and environmental preservation are
Continued advancements in seawater extraction
necessary to salvage terrestrial mine sites
Scientists and engineers have applied large amounts of
time and energy to the study of more economical methods of
extracting uranium from seawater, which has produced very
promising results. However, in order to solidify seawater
uptake as the preferred and universal method of extraction,
these studies must continue. Scientists agree that “the work
is promising enough to begin to remove a concern about the
sustainability of terrestrial sources and any stumbling block
that may present to growth in the nuclear power industry”
[7]. Not only are terrestrial sources very limited in the face
of increased demand for uranium in the energy industry, but
mining sites on land pose great threats to health and the
environment. Waste rock and chemical agents alter the land
and groundwater of the mining site and contain radioactive
materials that are released into the environment, posing
serious risks to public health. The dangers and lifespan of
these poisonous substances are threats that seawater
extraction could eradicate.
As a future engineer and concerned citizen, I encourage
the continued, rigorous study into extraction of uranium
from seawater and applaud the strides made thus far. I
believe we should utilize natural resources in the most
efficient and least threatening manner. The extraction of
uranium from seawater does not damage the water or
surrounding area. The amidoxime-polymer sorbents do not
remain in the water and are treated with acids to extract the
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Caren Dieglio
both at risk under current uranium mining techniques.
Uranium extraction from seawater does not pose a threat to
either health or the environment, thus making it vital that a
more economically-feasible method of seawater extraction is
engineered.
Study of Current Engineering Issue Introduces Students
to Engineering Applications Outside of the Classroom
The engineering Codes of Ethics remind engineers that
their work does not only impact them, but affects the
surrounding community as well. Oftentimes, engineers
become intensely involved in their work and forget that their
work is intended to engineer a better world. The NSPE
Code of Ethics reminds engineers of their role in society
when it states, “Engineering has a direct and vital impact on
the quality of life for all people” [9]. Like engineers,
students must be reminded at times that there exists a world
beyond their schoolwork.
My study into the current practices of uranium mining,
the new, innovative methods of seawater extraction, the
health and environmental hazards that terrestrial mining
produce, and the ethical dilemmas that result from these
risks, has enlightened me to an issue that extends beyond the
classroom and affects the larger community. My research
has built a bridge between my schoolwork and my future,
introducing me to how the material I am currently studying
will apply to my future as a practicing engineer. I was able
to perceive how knowledge, which the engineers working on
uranium extraction from seawater clearly possess, and
rigorous research, which they have been conducting, serve
as vital tools in engineering careers. In addition, the
research I performed and consideration I applied to ethics
introduced me to a current engineering issue and its effects
of which I likely would have remained unaware were I not to
research.
Too often, engineering students consider their studies to
be the first priority in all cases, leading to a hermit-like
lifestyle in which these future engineers confine themselves
to their rooms until studying is complete. The findings of a
2011 National Survey of Student Engagement support this
claim. The survey found that 42% of engineering students
reported studying more than 20 hours each week, thus
making engineering the major whose students “spend the
most time studying and the least on outside demands” [12].
Of course, studying is an essential practice that engineering
students must master, yet mastery of this skill must not blind
students to important matters in the greater community My
experience researching uranium extraction from seawater
and forming a position on the issue has broadened my
perspective beyond the classroom, thus acquainting me with
current engineering topics and introducing me to dilemmas,
both practical and ethical, I may face in my future as an
engineer. Because of the positive effects this assignment has
had on my learning experience, I regard it as a valid and
effective educational tool that encourages engineering
students to set down the books for a moment and consider
the advancements their future coworkers are making in the
world and the ethical aspects involved in the engineering
discipline.
Uranium Extraction from Seawater Proves to be an
Ethical Alternative
The possibility of poisonous radon gas being emitted during
terrestrial mining and then inhaled by miners and
surrounding communities is unacceptable. In addition, the
land around mining sites is irreversibly altered and adversely
affected by the toxic groundwater pollution, waste rock, and
craters that result from uranium mining. The environmental
and health dangers are ethical dilemmas that all three
aforementioned Codes of Ethics regard as the responsibility
of engineers to solve. The ANS makes it evident in its Code
that the environment and safety are not to be neglected when
the Code reads, “We will formally advise our employers,
clients, or any appropriate authority . . . when we perceive
that pursuit of our professional duties might have adverse
consequences for the present or future public and fellow
worker health and safety or the environment” [11]. In
addition to its earlier statement on public welfare, the NSPE
Code obliges engineers “to adhere to the principles of
sustainable development in order to protect the environment
for future generations” [9]. The engineers researching
uranium extraction from seawater, and all chemical and
nuclear engineers, are held to these ethical guidelines that
necessitate protection of public welfare and the environment,
thus making the progress of this study even more pressing.
These codes of ethics strongly reinforce my belief and
assertion that alternate methods of uranium mining be
explored and devised. I consider the health risks and
environmental perils created by terrestrial mining to be
unnecessary dangers that can be avoided if different mining
techniques are employed. The Codes of Ethics make it
evident that engineers are morally obligated to the task of
eradicating these risks by creating those new mining
techniques. As a future engineer, I am concerned for the
environment and promote sustainability, and as an ethical
being, I care for the safety and health of the community.
Thus, it is encouraging that various Codes of Ethics across
the engineering disciplines support my position by holding
engineers to high ethical standards and, consequently,
leading to an increased concern for safety and the
environment. Consideration of the ethical expectations to
which they are held should serve as an impetus for the
engineers devising methods of seawater extraction to create
a product that protects public welfare and salvages the only
environment we have.
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Caren Dieglio
[5] (7 August 2012). “Health Effects.” U.S. Environmental
Protection
Agency.
(Online
Website).
http://www.epa.gov/rpdweb00/understand/health_effects.ht
ml
[6] M. Jacoby. (2012). “Extracting Uranium from Seawater.”
Chemical and Engineering News. (Online Article).
http://cen.acs.org/articles/90/i36/Extracting-UraniumSeawater.html. pp. 60-63
[7] (2012). “Uranium from Seawater Idea Boosted with
Shrimp
Shells.”
BBC
News.
(Online
Article).
http://www.bbc.co.uk/news/science-environment-19335708
[8] DOE/Oak Ridge National Laboratory. (2012). “Moving
Closer to Extracting Uranium from Seawater.” ScienceDaily.
(Online
Article).
http://www.sciencedaily.com/releases/2012/08/1208212126
34.htm
[9] (July 2007). “NSPE Code of Ethics for Engineers.”
National Society of Professional Engineers. (Online
Website).
http://www.nspe.org/Ethics/CodeofEthics/index.html
[10] “Code of Ethics.” American Institute of Chemical
Engineers.
(Online
Website).
http://www.aiche.org/about/code-ethics
[11] (June 2003). “Code of Ethics.” American Nuclear
Society.
(Online
Website).
http://www.new.ans.org/about/coe/
[12] R. Perez-Pena. (17 November 2011). “Would-Be
Engineers Hit Books the Hardest, a Study Finds.” The New
York
Times.
(Online
Article).
http://www.nytimes.com/2011/11/17/education/collegestudent-survey-shows-balance-of-work-andstudy.html?_r=1&
Breaking Down the Economic Hurdle of Uranium
Extraction from Seawater
A concern for the environment and public safety and an
awareness that terrestrial sources of uranium are limited
compels me to support the extraction of uranium from
seawater. Additionally, study of the NSPE, AIChE, and
ANS Codes of Ethics reveals that the engineering
community shares my concern for public welfare and the
environment. Traditional uranium mining methods concern
me for they expose miners to gaseous poisons and pose
dangerous possibilities of radon emission and water
pollution. I support the viable and preferable alternative of
seawater extraction, yet the fiscal burden this method carries
is a challenging obstacle.
Studies and experiments
conducted worldwide have begun to break down this hurdle,
yet the economic stress of uranium uptake from seawater
still remains. Nevertheless, an economic burden must not be
considered of greater importance than health and
environmental considerations that the Codes of Ethics
enforce. With promising advancements made in recent,
innovative research into the adsorbents used in uranium
extraction, a path is being laid for engineers to continue their
work towards discovering a method of extraction that will
both reduce cost and salvage the environment and health of
communities surrounding current terrestrial mining sites. It
is essential that engineering students recognize the
innovation occurring within their future field of work,
continue to educate themselves in the classroom, and
familiarize themselves with current engineering research.
An assignment such as the one upon which I just endeavored
is a unique tool that educates engineering students both in
and out of class. The creation of a sound method of uranium
extraction from seawater yields positive results for public
welfare and the environment, adheres to engineering Codes
of Ethics, and raises awareness of advancements being made
by engineers. Thus, uranium extraction from seawater
should continue to be actively and aggressively studied and
pursued by engineers.
ADDITIONAL SOURCES
[1] “What is Uranium Used For?” Uranium & the
Community.
(Online
Article).
http://www.uraniumsa.org/uses/uses.htm
ACKNOWLEDGEMENTS
REFERENCES
I would like to thank Professor Len Kogut, who
introduced me to the concept of extracting uranium from
seawater in his General Chemistry for Engineers class. A
special thank you is also in order for Janine Carlock and
Beth Bateman Newborg, who provided assistance and
guidance during the writing of this paper. A final thank you
goes to Br. Philip Smith, my Advanced Placement English
12 teacher, who provided me with a strong, solid foundation
in research and writing.
[1] “Ocean.” National Oceanic and Atmospheric
Association.
(Online
Article).
http://www.noaa.gov/ocean.html
[2] P. Diehl. (2011). “Uranium Mining and Milling Wastes:
An Introduction.” WISE Uranium Project. [Online Blog].
http://www.wise-uranium.org/uwai.html
[3] “Gordon Edwards of CCNR: Should Uranium Mining be
Allowed?” MiningWatch Canada. (29 November 2011).
(Video). http://www.miningwatch.ca/gordon-edwards-ccnrshould-uranium-mining-be-allowed
[4] “How is Uranium Mined and Processed?” Keep the Ban.
[Online Blog]. http://keeptheban.org/?page_id=744
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Caren Dieglio
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