Viable Nuclear Waste Disposal
Safety Methods or precautions taken when dealing with nuclear/radioactive waste and methods of disposal that follows industrial procedure.
Content
Energy Policy 39 (2011) 1382–1388
Contents lists available at ScienceDirect
Energy Policy
journal homepage: www.elsevier.com/locate/enpol
Toward a viable nuclear waste disposal program
Marvin Baker Schaffer n
RAND Corporation, 1776 Main Street, Santa Monica, CA 90407, United States
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 16 August 2010
Accepted 6 December 2010
Available online 13 January 2011
The essay deals with the lack of a suitable permanent storage site for the radioactive waste that has been
produced by more than 103 open-cycle nuclear reactors in the U.S. The DOE has recently withdrawn the
licensing application for the Yucca Mountain Repository leaving the nuclear industry responsible for the
safety of more than 800 waste-containing concrete casks currently on the open surface at 34 sites. It also has
not undertaken measures to reduce the volume of additional waste produced by both existing and newly
planned reactors. The DOE has instead opted to undertake research to develop new cycles that ’’burn’’ the
radioactive waste. This policy appears subordinated to obvious political pressures. It is short sighted in
terms of a practical program to serve the interests of the clean and safe energy requirements of the country.
The essay also describes technical initiatives and processes that are recommended for a better solution.
& 2010 Elsevier Ltd. All rights reserved.
Keywords:
Nuclear waste disposal policy
Management of commercial nuclear waste
Viable nuclear energy
1. Introduction
There is a growing consensus that increased investment in
commercial nuclear power is necessary to satisfy future national
energy demand. The U.S. Department of Energy (DOE) has forecast
that domestic electricity demand will increase about 30% by the
year 2035. That means America will require hundreds of new power
units. Nuclear energy’s share is forecast to be 11–20% depending on
whether total economic growth is low or high. New nuclear reactors
will be required to achieve either share. The U.S. Nuclear Regulatory
Commission (NRC) is now reviewing 13 license applications for 22
new nuclear power plants to address that demand.
All of the currently operating commercial nuclear plants in the
U.S. and all of the proposed facilities are of the open cycle (batch)
variety that generates highly radioactive nuclear waste. The existing
waste material is temporarily stored in underground water container pools and in concrete steel-lined casks on the surface near the
reactors. Currently, about 800 nuclear waste casks exist on 34 sites.
There are serious problems associated with long-term accumulation
of this toxic material. Alternative strategies for managing waste and
alleviating these problems are possible, as discussed later. Briefly,
the open cycle with no reprocessing will be compared to cycles with
uranium and plutonium reprocessing, full recycling, and fully sealed
waste alternatives. The phased implementation of these measures is
implied but not established herein with precision. Clearly, however,
we must manage open-cycle waste disposal early or the incentive to
open new facilities will be diminished. Uranium and plutonium
reprocessing, full recycling, and fully sealed waste alternatives are
attractive for the longer term.
n
Tel.: 13103930411 x8393; Mobile: 13109802751.
E-mail address: [email protected]
0301-4215/$ - see front matter & 2010 Elsevier Ltd. All rights reserved.
doi:10.1016/j.enpol.2010.12.010
A key issue complicating the policy discussion is that the DOE
has reversed a 30-year old commitment to provide a permanent
storage repository leaving the industry with complete responsibility for safeguarding existing nuclear waste. Not only is this
unjustifiable from an economic standpoint, it threatens the viability of new open-cycle reactors. Significantly, it also perpetuates a
situation that allows tempting targets for terrorists. These are
urgent issues that the Obama Administration either does not seem
to recognize or does not care about in its pursuit of ‘‘optimal
technology’’ for future nuclear reactors.
2. What is nuclear waste?
Nuclear fuel in America’s open-cycle reactors consists of ceramicencased low-enriched uranium oxide pellets packed into zirconiumclad tubes (rods). These are bundled into ‘‘fuel assemblies’’ each
weighing as much as 700 kg. Most open-cycle, once-through reactors
produce long-lived radioactive waste that must be stored. Their halflives range from many millions of years to one week. By way of contrast,
closed-cycle reactors either do not produce substantial amounts of
highly radioactive waste or can be coupled to reprocessors that recover
most of the troublesome bi-products.
As summarized in Table 1, low-enriched open-cycle uranium
fuel is a mixture of two isotopes, uranium-235 and uranium-238.
Uranium-235 is the workhorse. It is fissile (splits) releasing large
quantities of energy in the presence of thermal (low-energy)
neutrons that dominate light water reactors. Uranium-238 is
relatively but not completely inert to these. Only a small portion
of the uranium-238 is fissionable and splits directly, adding to the
power output. However, uranium-238 readily absorbs the sparsely
populated fast (high-energy) neutrons that are also produced and is
therefore considered fertile. The fertilized uranium-238 ultimately
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
converts to plutonium-239 that then also fissions, adding further to
the power output. Near the end of the cycle, about half the power
derives from plutonium fission.
The principal cycle however involves uranium-235 and it ends
when that isotope has been depleted by fission to about 0.7%. Other
actinides such as americium-241 and technetium-99 are produced
in small amounts. (The actinide series encompasses atomic numbers
from 90 to 103 of which only uranium and thorium occur naturally
in usable quantities.) Note that none of these waste products are
highly radioactive since they possess long half-lives. Perversely,
most of the fission products (typically strontium-90, cesium-137,
and iodine-131) have short half-lives and are highly poisonous.
3. Alternative approaches to commercial nuclear power design
All of the 103 operating commercial nuclear power plants in the U.S.
are of the open-cycle, batch variety. New plants under consideration
are more efficient, but all are still open cycle. In contrast, many facilities
operating in Europe and Asia are fundamentally different. They recycle
rather than dispose of the plutonium that is inevitably produced
thereby substantially reducing the waste problem and greatly extending the fuel supply. Still a third possibility exists, namely full recycling
wherein transuranic elements (heavier than uranium) are extracted
and burned in fast reactors. That technique has been studied extensively but has not achieved full production status.
Finally, there are TRISO-fueled reactors, including the Pebble Bed
variety, that produce highly depleted waste in small, secure containers. Each of these cycles is examined in detail from the waste disposal
point of view. A preliminary comparison is provided in Fig. 1.
4. The open-cycle nuclear waste disposal problem
Spent nuclear fuel from open-cycle commercial reactors has
accumulated in temporary storage at 34 sites in the U.S. over a
50-year period. The U.S. Congress recognized the need for a
consolidated storage site when it adopted the Nuclear Policy Act
of 1982; it called for the isolation of spent fuel in deep underground
repositories, and in 1987, Yucca Mountain, Nevada was chosen as
the single focus for further development. In 2002 a timeline was
established for opening Yucca Mountain in 2017. About 10 billion
dollars has been expended toward that end thus far.
Yucca Mountain is located in the Mojave Desert about 160 km
from Las Vegas. It is intended to contain an underground network of
horizontal tunnels roughly 300 m below the surface and 300 m
above the water table. The tunnels can accommodate 70,000 tons of
nuclear waste. Fig. 2 conceptually illustrates how waste containers
are stored in the tunnels.
It is in the interest of the country for the Yucca Mountain
initiative to remain viable and on schedule. However, in response to
political pressure from Nevada officials, the DOE has filed a motion
with the NRC to withdraw (with prejudice) the license application
for Yucca Mountain operations. Moreover, the President’s fiscal
Table 1
Open-cycle transformation of nuclear fuel into waste.
Uranium-238
Uranium-235
Plutonium-239
Actinidesa
Fission productsb
Low-enriched fuel
charge (%)
Waste (%)
Half-life (years)
95.8
4.2
0
0
0
92.7
0.71
1.27
0.14
5.15
4.47 109
7.04 106
24,110
432–212,000
0.02–30.07
a
Mostly uranium-234, neptunium-237, plutonium-238, americium-241 and
technetium-99.
b
Often containing strontium-90, cesium-137, and iodine-q131.
1383
Fig. 2. Storage of nuclear waste at Yucca Mountain.
Fig. 1. Comparing nuclear fuel cycles.
1384
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
year 2011 budget request eliminated funding for the Office of
Civilian Radioactive Waste Management.
Administration policy on commercial nuclear power lacks
consistency and clarity. On the one hand, the White House has
announced that it is working to ‘‘restart America’s nuclear industry’’ coupling that policy with the objectives of meeting energy and
climate challenges and creating thousands of new jobs. Similarly,
the Administration has also stated that it is ‘‘fully committed to
ensuring that long-term storage obligations for nuclear waste are
met’’. However, the President has also made it clear that the Yucca
Mountain site is not an option for waste storage.
The inconsistencies of the foregoing are obvious. Prior to 2009,
the DOE had steadfastly defended the viability and safety of Yucca
Mountain. Yucca Mountain has an initial capacity to accommodate
all of the industry’s current backload, and the inherent potential to
increase that quantity substantially. Abandonment of the Yucca
Mountain license leaves the nuclear industry in a difficult quandary. To cushion the reversal of policy, a blue ribbon commission
under the joint chairmanship of the Honorable Lee Hamilton and
General Brent Scowcroft has been established to investigate longterm solutions. Both chairmen are distinguished politicians and
advisors to former administrations, but they have little or no
expertise in nuclear physics or geology. Opposition critics have
postulated that a delaying tactic for implementing America’s
nuclear power program has been put in place for political purposes.
To quote Voltaire, perfect is the enemy of the good.
Since the country is now without a committed permanent
nuclear waste repository site, the future of the industry in the U.S. is
in peril. Nuclear wastes for the 103 U.S. nuclear reactors continue to
be stored in on-site tanks and casks, which is risky and inefficient
and clearly unsustainable. It is risky because the storage casks on
the surface are potential targets for terrorist attack. It is inefficient
because numerous storage facilities are being maintained at
significant incremental cost as opposed to expenditures for a
consolidated facility like Yucca Mountain. The principle of economy of scale is being ignored. It is unsustainable because high-level
waste in the on-site casks has a radioactive half-life of hundreds of
thousands of years whereas the structural integrity of the casks is
only 100 years at best. In 100 years, the plant itself will be long
closed and decommissioned. The casks will either have to be moved
or monitored separately. In a consolidated facility like Yucca
Mountain, a dedicated maintenance staff can repair corrosion
and other observed damage systematically as required.
As more open-cycle nuclear plants come on line, the problem
gets worse. It can be estimated that for the 250 nuclear plants in
operation in the U.S. four decades from now, a new Yucca Mountain
(type) disposal facility will have to be opened every fifteen years.
How do we proceed with that storage facility demand when even
the first Yucca Mountain has run into obstacles?
5. Not in my back yard (NIMBY)
There are two significant components to solving the open-cycle
nuclear waste disposal problem on a permanent basis. The first is
the community confidence issue that needs to be addressed. The
NIMBY syndrome is very powerful. In the case of Yucca Mountain,
when Congress picked the site in 1987, it did so without the
approval of the state of Nevada. Even after an unsuccessful lawsuit,
Nevada officials have remained aggressively opposed to opening
the site. Some argue it is geologically inadequate despite the
extensive validating studies made by DOE. Others warn of a falloff
of tourism in Las Vegas although there is no evidence that this will
be the case. Still others maintain that transporting the waste to
Yucca Mountain is unsafe. All these issues have dubious validity but
retain significant leverage in Washington.
Presently, although existing waste material is temporarily stored in
underground water container pools and in concrete steel-lined casks on
the surface near the reactors, there is a community-endorsed requirement for permanent storage. That approach has worked well elsewhere. In Carlsbad, New Mexico, for example, the Waste Isolation Pilot
Plant for storing nuclear tailings from weapons manufacture has been
in operation since the 1970s with the strong endorsement of the local
community. Originally engaged in potash mining that was on the brink
of depletion, the locals broached the waste storage idea to the Atomic
Energy Commission (NRC predecessor) and have supported it ever
since. Countries such as Sweden have faced similar challenges and
made successful decisions after suitable research and public education
about their waste. The Swedes have a well-rounded program. For
example, they have a dedicated ship that moves used fuel from power
plants to repositories. They have two repositories for storing high-level
waste, one interim and one final. The final repository has been
established with the cooperation of local residents.
A confidence-enhancing plan should:
Spread the risks: identifying three or four sites instead of one
signals that the program is methodical and not arbitrary
Limit the term: specify storage for a nominal period (say 100 years)
Provide substantial monetary incentives
Provide transparency: extensive disclosure about risks and rewards.
With nuclear waste rationally stored for about 100 years, one or
more final geologic sites or other disposal methods could then be
selected with the help of evolving technologies. Some of those
technologies include reprocessing, discussed next.
6. Reprocessing nuclear waste
The other component of the long-term solution involves reducing the amount of high-level waste to be stored. If wastes are
reprocessed to extract uranium and plutonium, for example, not
only will radioactive residuals be reduced, but also fuel abundance
will be enhanced dramatically.
There are well-developed (albeit complex) methods for reprocessing. They are generally based on the PUREX (Plutonium and
Uranium by Extraction) method. In that process, depleted fuel rods
are cut into pieces and dissolved in nitric acid. The resulting liquid
solution contains uranium, a smaller fraction of plutonium, and
mixed actinides. It is then possible to separate the uranium,
plutonium, and actinides using liquid–liquid extraction techniques. The extracted stream contains uranium-235 at 0.7–0.9%
which can then be burned in heavy-water-moderated reactors or
fast-neutron reactors for additional energy. The plutonium-239 can
be used to prepare MOX (mixed oxide uranium and plutonium)
fuel, which is the preferred option in Europe. Remaining actinides
can be vitrified (encased in glass) with a large volume reduction in a
configuration that is resistant to water leaching. An alternative is to
encase the actinides in stainless steel containers.
Fig. 3 summarizes the PUREX process. Note that several countries
including France and Japan already reprocess their nuclear waste
using PUREX. The U.S. does not due to a late 1970s policy that was
intended to constrain nuclear proliferation. The rationale is that
reprocessing includes isolating plutonium that can conceivably be
used for assembling nuclear weapons. However, the notion that the
U.S. cannot safeguard the plutonium it isolates is inconsistent with
all the successful precautions that have been taken for protecting
other potential bomb-making materials (such as highly enriched
uranium and tritium). Instead of reprocessing waste, Energy Secretary Steven Chu recently told Congress that efforts are underway to
develop a new generation of reactors that can burn waste (that is
discussed later). However, we are probably several decades away
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
1385
Fig. 3. The PUREX process (Benedict et al., 1981).
from having the technology to burn waste commercially whereas
the need for waste reduction is current and reprocessing is existing
technology. Administration policy about PUREX thus has at least
the appearance of a delaying tactic whose net effect endangers the
reemergence of a vibrant nuclear industry.
7. Full recycling of nuclear waste
Researchers at Argonne National Laboratory have been studying
and advocating closed-cycle fast-reactor technology for many
years (Hannum et al., 2005). They point to the advantages of an
Advanced Liquid Metal Reactor (ALMR) that is integrated with
high-temperature pyrometallurgical processing for recycling and
replenishing fuel. ALMR uses energetic neutrons to interact with
abundant uranium-238 in metallic form to eventually produce
plutonium-239. In ALMR, fast neutrons are plentiful because liquid
sodium is used as the coolant and moderator instead of water that
slows neutrons down. Fast reactors are considerably more efficient.
The net result is that uranium-235, uranium-238, plutonium-239,
and a substantial fraction of other transuranics all undergo fission
to produce power. The composite used fuel is a mixture of uranium
and transuranic elements. Pyrometallurigical processing then
separates the uranium which can be reused.
8. Pyrometallurgical processing
Pyrometallurgical processing extracts a mix of transuranic
elements from used fuel and not the pure plutonium that PUREX
reprocessing separates. This has advantages in a counter-proliferation sense since plutonium-239 is not easily separated from other
transuranic elements and that poisons potential weapon manufacturing. Pyrometallurgical processing is based on electroplating
to collect metal extracted as ions from a chemical bath.
The process is illustrated in Fig. 4. Spent fuel elements are placed in
the anode basket and dissolved in a chemical bath. Pure uranium
collects on the solid cathode, while a mixture of transuranic (TRU)
elements, uranium, and rare earth (RE) fission products deposit on the
Fig. 4. Pyroelectric refining of nuclear waste.
liquid cadmium cathode. That mixture can be burned in fast reactors
after further processing. Other fission products distribute between the
salt and cadmium phases according to the solubility of their chlorides.
Basic pyrometallurgical processes have been developed both in
the U.S. and Russia. The U.S. process produces metallic uranium
whereas the Russians produce uranium oxide. Both processes have
been demonstrated on a pilot plant basis but full production
requires extensive development. Although advantageous in theory,
they cannot substitute for the near-term need to permanently store
open-cycle wastes that have already been and continue to be
extensively accumulated.
9. Vitrifying nuclear waste
Vitrification (glass encasement) is the preferred technique
to contain and dispose of residual actinides from PUREX reprocessing and pyrometallurgic refining. It is an important process for
reducing the volume and minimizing the contamination risks of
high-level nuclear wastes. Vitrification containers are suitable for
1386
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
long-term storage in below ground facilities like Yucca Mountain.
Several countries have already vitrified high-level waste and others
are studying the technology. They include the U.S., France, U.K.,
Germany, Belgium, Japan, Russia, and India.
A typical vitrification process is illustrated in Fig. 5.
10. Self-contained, highly depleted nuclear waste
An alternative to reprocessing or refining is to produce a variety
of waste that is self-contained, depleted to the point where it is not
a proliferation problem and storable in underground sites without
concerns about water leaching or seismic damage. TRISO-fueled
reactors provide that capability (Schaffer, 2007). TRISO (tri-structural isometric) fuel is the enabling technology for an advanced
class of reactors with two major variants. One variant, called a
pebble bed reactor, permits a continuous fuel loading/unloading
process. The second employs TRISO fuel in annular prismatic blocks
that are unloaded and replaced after a suitable burn-up period.
(The first variant is closed cycle and the second is open cycle.)
A pebble-bed nuclear reactor is currently operating in China while
TRISO reactors in prismatic configurations are operating in Japan
and Russia. Pebble Bed reactors are also being considered by the
DOE for further development in the U.S.
Fig. 6 displays the design of pebble bed TRISO fuel. The fuel
consists of enriched uranium ( 8%) or thorium kernels each of
which is coated successively with layers of porous carbon, silicon
carbide, and pyrolytic carbon. The layers create a barrier against
fission product release while permitting the transfer of neutrons
and heat energy. In the pebble bed variant, the fuel kernels, each
about 1 mm in diameter, are embedded in a 50-mm graphite
(spherical) pebble. Each fuel pebble contains about 15,000 kernels
and a typical reactor contains several hundred thousand pebbles.
The spent fuel in a TRISO-fueled plant has favorable attributes
from both a storage and non-proliferation point of view. The spent
pebbles are safe to store without cooling, and are impervious to
water leaching. Although there is a small buildup of plutonium239, it is highly diluted with other plutonium isotopes in a difficultto-separate mixture that does not permit a useable explosive
device. The principal component of the spent fuel is uranium238 oxide. Also present is a mixture of actinides and fission
products, all securely contained. Uranium-235 has been depleted
to a level less than that of natural uranium and the spent pebbles
are considered safe for underground storage. It has also been
suggested that they can be disposed of on deep ocean floors
without concern.
11. Risk analysis
Risk is a core issue for nuclear waste disposal. Risk is frequently
cited by critics as the key rationale for stopping further commercial
Fig. 5. Exemplar vitrification design (Penrice, 2008).
0.92-mm
coated particle
Silicon carbide barrier coating
Pyrolytic coating
60-mm
fuel speres
Inner pyrolytic coating
Porous carbon buffer
0.5-33 fuel kernel
Coated particles
embedded in
graphite mix
0.5-mm fuel
kernel Uranium
dioxide
5-mm
graphite layer
Fig. 6. TRISO fuel design.
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
nuclear reactor construction. Nuclear waste disposal risk can be
broken down systematically as follows:
Terrorist attack of dry cask storage at plant site
The most effective attack would be with shaped charge weapons. Terrorists would have to penetrate to within 50 m of the
casks, through plant security, and deliver the weapons with
rocket or recoilless rifle fire. Alternatively, they could attack
with indirect fire weapons albeit with less accuracy. Since the
waste is encased in steel and concrete, the worst case is that
radioactive materials would be dispersed within a few meters of
the impacted casks. No explosion would occur. The shaped
charge jets would penetrate into the cask interiors and produce
an internal shock wave. The risk would be borne by people living
near the plant but the probability of radioactive exposure would
be slight-to-zero.
Accident or terrorist attack while transporting casks
Effects are similar to those for on-site attacks. The important
point is that no explosion would occur internal to the casks.
Radioactive dispersal risks are again limited to a few meters and
the probability of widespread contamination is slight to zero.
Risk of water table contamination while in permanent storage
The purpose of storage in sites like Yucca Mountain is to
minimize water table and other external contamination for
periods of 100 years or so. The DOE has spent billions of dollars
analyzing these risks and they are vanishingly small. It is
assumed the facility will be guarded against terrorist attack.
This is significantly less difficult than protecting several hundred nuclear plants. In 100 years or so, the situation can be
revisited, but it seems likely that time extensions will be granted
in most cases. Eventually newer technology will emerge. This
may include deep-sea storage, storage in the upper mantle of
the earth, or delivering waste into space toward the sun. For
various reasons, none of these are feasible now, but that may
change.
Risks associated with nuclear materials proliferation
These risks are real but controllable. Under present policy, there
is almost no risk. Plutonium-239 in existing waste is mixed with
Fig. 7. Comprehensive nuclear waste disposal program.
1387
contaminants that make it useless for weapons manufacture.
Uranium-235 is depleted so that it is less than or equal to natural
uranium concentration. The same is true for TRISO waste. The
proliferation risks for full recycling are similar; the uranium235 is extracted and reused as reactor fuel and the residual
transuranics are useless for weapons. Only in the PUREX process
is there a risk of plutonium-239 being stolen or diverted for
weapons manufacture. As previously noted, France and Japan
already use the PUREX process with safeguards for protecting
the plutonium-239. In the U.S., no plutonium-239 is produced as
a result of commercial refining processes, but if it was, the
safeguards could be the same as those for highly concentrated
uranium-235, tritium, and the plutonium-239 deliberately
produced for weapons.
12. Summary
The outline of a comprehensive nuclear waste program for the
U.S. is provided in Fig. 7.
A useful program should start with reopening the licensing
process for the Yucca Mountain waste disposal facility, and
investigating the feasibility of expanding its capacity. In addition,
the U.S. should restart one or more PUREX reprocessing plants to
help deal with the surplus of waste materials that Yucca Mountain
cannot cope with. New actinide vitrification facilities should also be
developed.
Concurrently, the search for more permanent storage sites
should continue. Congress should appropriate funds to educate
and assuage concerns that local communities have about nuclear
waste storage. The DOE and NRC should issue guidelines and
promotional materials to induce industry to build new TRISOfueled reactors. Finally, research into innovative technology that
burns nuclear waste should be intensified.
The Obama Administration may have misguided priorities
about commercial nuclear power. Short-shifting the national
nuclear waste storage program appears unwise and subordinated
to political pressures. Specifically, the Yucca Mountain initiative
has been terminated prematurely and defunded, and has been
replaced by a blue ribbon commission to find alternatives. That
approach does not exploit near-term, well-researched technology
for underground storage. It also does not take advantage of wellestablished techniques that are being pursued in Europe and Asia.
Significant capabilities already exist for reducing the amount and
volume of nuclear waste, specifically PUREX reprocessing, vitrification, and TRISO fuel configurations. The U.S. has a long and
successful history in all three, but this is being ignored. Current
opportunities for waste reduction are being overlooked. The
Administration has furthermore not made a serious attempt to
provide incentives to local communities for accommodating waste
storage at new sites. Inevitably, new waste storage sites in addition
to Yucca Mountain will be required. There is historical evidence
that incentives facilitate the process. The Bully Pulpit of the White
House could go a long way toward establishing a successful
incentives program.
Table 2
Comparison of risks with current policy.
Current policy
Yucca Mountain storage
PUREX refining
Full recycling
TRISO fuel
Terrorist attack
Transportation
Water contamination
Proliferation
Magnified by several hundred
Zero to slight
Less than current policy
Zero to slight
Zero to slight
Zero
Finite but slight
Finite but slight
Finite but slight
Essentially zero
Slight for about 100 years
Slight for about 100 years
Slight
Slight
Zero
Essentially zero
Zero
Finite for Pu-239
Essentially zero
Essentially zero
1388
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
A qualitative summary of the risks for various nuclear waste
disposal policies is provided in Table 2.
References
Benedict, M., Pigford, T.H., Levi, H.W., 1981. Nuclear Chemical Engineering second
ed. McGraw-Hill, New York.
Hannum, W.H., Marsh, G.E., Stanford, G.S., 2005. Smarter use of nuclear wastes.
Scientific American December, 84–91.
Penrice, C.H., 2008. Vitrification Assistance Program: International Cooperation on
Vitrification Technology. /www.wmsym.org/archives/2008/pdfs/8478.pdfS.
Schaffer, M.B., 2007. Nuclear power for clean, safe, and secure energy independence.
Foresight 9 (6), 47–60.
Contents lists available at ScienceDirect
Energy Policy
journal homepage: www.elsevier.com/locate/enpol
Toward a viable nuclear waste disposal program
Marvin Baker Schaffer n
RAND Corporation, 1776 Main Street, Santa Monica, CA 90407, United States
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 16 August 2010
Accepted 6 December 2010
Available online 13 January 2011
The essay deals with the lack of a suitable permanent storage site for the radioactive waste that has been
produced by more than 103 open-cycle nuclear reactors in the U.S. The DOE has recently withdrawn the
licensing application for the Yucca Mountain Repository leaving the nuclear industry responsible for the
safety of more than 800 waste-containing concrete casks currently on the open surface at 34 sites. It also has
not undertaken measures to reduce the volume of additional waste produced by both existing and newly
planned reactors. The DOE has instead opted to undertake research to develop new cycles that ’’burn’’ the
radioactive waste. This policy appears subordinated to obvious political pressures. It is short sighted in
terms of a practical program to serve the interests of the clean and safe energy requirements of the country.
The essay also describes technical initiatives and processes that are recommended for a better solution.
& 2010 Elsevier Ltd. All rights reserved.
Keywords:
Nuclear waste disposal policy
Management of commercial nuclear waste
Viable nuclear energy
1. Introduction
There is a growing consensus that increased investment in
commercial nuclear power is necessary to satisfy future national
energy demand. The U.S. Department of Energy (DOE) has forecast
that domestic electricity demand will increase about 30% by the
year 2035. That means America will require hundreds of new power
units. Nuclear energy’s share is forecast to be 11–20% depending on
whether total economic growth is low or high. New nuclear reactors
will be required to achieve either share. The U.S. Nuclear Regulatory
Commission (NRC) is now reviewing 13 license applications for 22
new nuclear power plants to address that demand.
All of the currently operating commercial nuclear plants in the
U.S. and all of the proposed facilities are of the open cycle (batch)
variety that generates highly radioactive nuclear waste. The existing
waste material is temporarily stored in underground water container pools and in concrete steel-lined casks on the surface near the
reactors. Currently, about 800 nuclear waste casks exist on 34 sites.
There are serious problems associated with long-term accumulation
of this toxic material. Alternative strategies for managing waste and
alleviating these problems are possible, as discussed later. Briefly,
the open cycle with no reprocessing will be compared to cycles with
uranium and plutonium reprocessing, full recycling, and fully sealed
waste alternatives. The phased implementation of these measures is
implied but not established herein with precision. Clearly, however,
we must manage open-cycle waste disposal early or the incentive to
open new facilities will be diminished. Uranium and plutonium
reprocessing, full recycling, and fully sealed waste alternatives are
attractive for the longer term.
n
Tel.: 13103930411 x8393; Mobile: 13109802751.
E-mail address: [email protected]
0301-4215/$ - see front matter & 2010 Elsevier Ltd. All rights reserved.
doi:10.1016/j.enpol.2010.12.010
A key issue complicating the policy discussion is that the DOE
has reversed a 30-year old commitment to provide a permanent
storage repository leaving the industry with complete responsibility for safeguarding existing nuclear waste. Not only is this
unjustifiable from an economic standpoint, it threatens the viability of new open-cycle reactors. Significantly, it also perpetuates a
situation that allows tempting targets for terrorists. These are
urgent issues that the Obama Administration either does not seem
to recognize or does not care about in its pursuit of ‘‘optimal
technology’’ for future nuclear reactors.
2. What is nuclear waste?
Nuclear fuel in America’s open-cycle reactors consists of ceramicencased low-enriched uranium oxide pellets packed into zirconiumclad tubes (rods). These are bundled into ‘‘fuel assemblies’’ each
weighing as much as 700 kg. Most open-cycle, once-through reactors
produce long-lived radioactive waste that must be stored. Their halflives range from many millions of years to one week. By way of contrast,
closed-cycle reactors either do not produce substantial amounts of
highly radioactive waste or can be coupled to reprocessors that recover
most of the troublesome bi-products.
As summarized in Table 1, low-enriched open-cycle uranium
fuel is a mixture of two isotopes, uranium-235 and uranium-238.
Uranium-235 is the workhorse. It is fissile (splits) releasing large
quantities of energy in the presence of thermal (low-energy)
neutrons that dominate light water reactors. Uranium-238 is
relatively but not completely inert to these. Only a small portion
of the uranium-238 is fissionable and splits directly, adding to the
power output. However, uranium-238 readily absorbs the sparsely
populated fast (high-energy) neutrons that are also produced and is
therefore considered fertile. The fertilized uranium-238 ultimately
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
converts to plutonium-239 that then also fissions, adding further to
the power output. Near the end of the cycle, about half the power
derives from plutonium fission.
The principal cycle however involves uranium-235 and it ends
when that isotope has been depleted by fission to about 0.7%. Other
actinides such as americium-241 and technetium-99 are produced
in small amounts. (The actinide series encompasses atomic numbers
from 90 to 103 of which only uranium and thorium occur naturally
in usable quantities.) Note that none of these waste products are
highly radioactive since they possess long half-lives. Perversely,
most of the fission products (typically strontium-90, cesium-137,
and iodine-131) have short half-lives and are highly poisonous.
3. Alternative approaches to commercial nuclear power design
All of the 103 operating commercial nuclear power plants in the U.S.
are of the open-cycle, batch variety. New plants under consideration
are more efficient, but all are still open cycle. In contrast, many facilities
operating in Europe and Asia are fundamentally different. They recycle
rather than dispose of the plutonium that is inevitably produced
thereby substantially reducing the waste problem and greatly extending the fuel supply. Still a third possibility exists, namely full recycling
wherein transuranic elements (heavier than uranium) are extracted
and burned in fast reactors. That technique has been studied extensively but has not achieved full production status.
Finally, there are TRISO-fueled reactors, including the Pebble Bed
variety, that produce highly depleted waste in small, secure containers. Each of these cycles is examined in detail from the waste disposal
point of view. A preliminary comparison is provided in Fig. 1.
4. The open-cycle nuclear waste disposal problem
Spent nuclear fuel from open-cycle commercial reactors has
accumulated in temporary storage at 34 sites in the U.S. over a
50-year period. The U.S. Congress recognized the need for a
consolidated storage site when it adopted the Nuclear Policy Act
of 1982; it called for the isolation of spent fuel in deep underground
repositories, and in 1987, Yucca Mountain, Nevada was chosen as
the single focus for further development. In 2002 a timeline was
established for opening Yucca Mountain in 2017. About 10 billion
dollars has been expended toward that end thus far.
Yucca Mountain is located in the Mojave Desert about 160 km
from Las Vegas. It is intended to contain an underground network of
horizontal tunnels roughly 300 m below the surface and 300 m
above the water table. The tunnels can accommodate 70,000 tons of
nuclear waste. Fig. 2 conceptually illustrates how waste containers
are stored in the tunnels.
It is in the interest of the country for the Yucca Mountain
initiative to remain viable and on schedule. However, in response to
political pressure from Nevada officials, the DOE has filed a motion
with the NRC to withdraw (with prejudice) the license application
for Yucca Mountain operations. Moreover, the President’s fiscal
Table 1
Open-cycle transformation of nuclear fuel into waste.
Uranium-238
Uranium-235
Plutonium-239
Actinidesa
Fission productsb
Low-enriched fuel
charge (%)
Waste (%)
Half-life (years)
95.8
4.2
0
0
0
92.7
0.71
1.27
0.14
5.15
4.47 109
7.04 106
24,110
432–212,000
0.02–30.07
a
Mostly uranium-234, neptunium-237, plutonium-238, americium-241 and
technetium-99.
b
Often containing strontium-90, cesium-137, and iodine-q131.
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Fig. 2. Storage of nuclear waste at Yucca Mountain.
Fig. 1. Comparing nuclear fuel cycles.
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M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
year 2011 budget request eliminated funding for the Office of
Civilian Radioactive Waste Management.
Administration policy on commercial nuclear power lacks
consistency and clarity. On the one hand, the White House has
announced that it is working to ‘‘restart America’s nuclear industry’’ coupling that policy with the objectives of meeting energy and
climate challenges and creating thousands of new jobs. Similarly,
the Administration has also stated that it is ‘‘fully committed to
ensuring that long-term storage obligations for nuclear waste are
met’’. However, the President has also made it clear that the Yucca
Mountain site is not an option for waste storage.
The inconsistencies of the foregoing are obvious. Prior to 2009,
the DOE had steadfastly defended the viability and safety of Yucca
Mountain. Yucca Mountain has an initial capacity to accommodate
all of the industry’s current backload, and the inherent potential to
increase that quantity substantially. Abandonment of the Yucca
Mountain license leaves the nuclear industry in a difficult quandary. To cushion the reversal of policy, a blue ribbon commission
under the joint chairmanship of the Honorable Lee Hamilton and
General Brent Scowcroft has been established to investigate longterm solutions. Both chairmen are distinguished politicians and
advisors to former administrations, but they have little or no
expertise in nuclear physics or geology. Opposition critics have
postulated that a delaying tactic for implementing America’s
nuclear power program has been put in place for political purposes.
To quote Voltaire, perfect is the enemy of the good.
Since the country is now without a committed permanent
nuclear waste repository site, the future of the industry in the U.S. is
in peril. Nuclear wastes for the 103 U.S. nuclear reactors continue to
be stored in on-site tanks and casks, which is risky and inefficient
and clearly unsustainable. It is risky because the storage casks on
the surface are potential targets for terrorist attack. It is inefficient
because numerous storage facilities are being maintained at
significant incremental cost as opposed to expenditures for a
consolidated facility like Yucca Mountain. The principle of economy of scale is being ignored. It is unsustainable because high-level
waste in the on-site casks has a radioactive half-life of hundreds of
thousands of years whereas the structural integrity of the casks is
only 100 years at best. In 100 years, the plant itself will be long
closed and decommissioned. The casks will either have to be moved
or monitored separately. In a consolidated facility like Yucca
Mountain, a dedicated maintenance staff can repair corrosion
and other observed damage systematically as required.
As more open-cycle nuclear plants come on line, the problem
gets worse. It can be estimated that for the 250 nuclear plants in
operation in the U.S. four decades from now, a new Yucca Mountain
(type) disposal facility will have to be opened every fifteen years.
How do we proceed with that storage facility demand when even
the first Yucca Mountain has run into obstacles?
5. Not in my back yard (NIMBY)
There are two significant components to solving the open-cycle
nuclear waste disposal problem on a permanent basis. The first is
the community confidence issue that needs to be addressed. The
NIMBY syndrome is very powerful. In the case of Yucca Mountain,
when Congress picked the site in 1987, it did so without the
approval of the state of Nevada. Even after an unsuccessful lawsuit,
Nevada officials have remained aggressively opposed to opening
the site. Some argue it is geologically inadequate despite the
extensive validating studies made by DOE. Others warn of a falloff
of tourism in Las Vegas although there is no evidence that this will
be the case. Still others maintain that transporting the waste to
Yucca Mountain is unsafe. All these issues have dubious validity but
retain significant leverage in Washington.
Presently, although existing waste material is temporarily stored in
underground water container pools and in concrete steel-lined casks on
the surface near the reactors, there is a community-endorsed requirement for permanent storage. That approach has worked well elsewhere. In Carlsbad, New Mexico, for example, the Waste Isolation Pilot
Plant for storing nuclear tailings from weapons manufacture has been
in operation since the 1970s with the strong endorsement of the local
community. Originally engaged in potash mining that was on the brink
of depletion, the locals broached the waste storage idea to the Atomic
Energy Commission (NRC predecessor) and have supported it ever
since. Countries such as Sweden have faced similar challenges and
made successful decisions after suitable research and public education
about their waste. The Swedes have a well-rounded program. For
example, they have a dedicated ship that moves used fuel from power
plants to repositories. They have two repositories for storing high-level
waste, one interim and one final. The final repository has been
established with the cooperation of local residents.
A confidence-enhancing plan should:
Spread the risks: identifying three or four sites instead of one
signals that the program is methodical and not arbitrary
Limit the term: specify storage for a nominal period (say 100 years)
Provide substantial monetary incentives
Provide transparency: extensive disclosure about risks and rewards.
With nuclear waste rationally stored for about 100 years, one or
more final geologic sites or other disposal methods could then be
selected with the help of evolving technologies. Some of those
technologies include reprocessing, discussed next.
6. Reprocessing nuclear waste
The other component of the long-term solution involves reducing the amount of high-level waste to be stored. If wastes are
reprocessed to extract uranium and plutonium, for example, not
only will radioactive residuals be reduced, but also fuel abundance
will be enhanced dramatically.
There are well-developed (albeit complex) methods for reprocessing. They are generally based on the PUREX (Plutonium and
Uranium by Extraction) method. In that process, depleted fuel rods
are cut into pieces and dissolved in nitric acid. The resulting liquid
solution contains uranium, a smaller fraction of plutonium, and
mixed actinides. It is then possible to separate the uranium,
plutonium, and actinides using liquid–liquid extraction techniques. The extracted stream contains uranium-235 at 0.7–0.9%
which can then be burned in heavy-water-moderated reactors or
fast-neutron reactors for additional energy. The plutonium-239 can
be used to prepare MOX (mixed oxide uranium and plutonium)
fuel, which is the preferred option in Europe. Remaining actinides
can be vitrified (encased in glass) with a large volume reduction in a
configuration that is resistant to water leaching. An alternative is to
encase the actinides in stainless steel containers.
Fig. 3 summarizes the PUREX process. Note that several countries
including France and Japan already reprocess their nuclear waste
using PUREX. The U.S. does not due to a late 1970s policy that was
intended to constrain nuclear proliferation. The rationale is that
reprocessing includes isolating plutonium that can conceivably be
used for assembling nuclear weapons. However, the notion that the
U.S. cannot safeguard the plutonium it isolates is inconsistent with
all the successful precautions that have been taken for protecting
other potential bomb-making materials (such as highly enriched
uranium and tritium). Instead of reprocessing waste, Energy Secretary Steven Chu recently told Congress that efforts are underway to
develop a new generation of reactors that can burn waste (that is
discussed later). However, we are probably several decades away
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
1385
Fig. 3. The PUREX process (Benedict et al., 1981).
from having the technology to burn waste commercially whereas
the need for waste reduction is current and reprocessing is existing
technology. Administration policy about PUREX thus has at least
the appearance of a delaying tactic whose net effect endangers the
reemergence of a vibrant nuclear industry.
7. Full recycling of nuclear waste
Researchers at Argonne National Laboratory have been studying
and advocating closed-cycle fast-reactor technology for many
years (Hannum et al., 2005). They point to the advantages of an
Advanced Liquid Metal Reactor (ALMR) that is integrated with
high-temperature pyrometallurgical processing for recycling and
replenishing fuel. ALMR uses energetic neutrons to interact with
abundant uranium-238 in metallic form to eventually produce
plutonium-239. In ALMR, fast neutrons are plentiful because liquid
sodium is used as the coolant and moderator instead of water that
slows neutrons down. Fast reactors are considerably more efficient.
The net result is that uranium-235, uranium-238, plutonium-239,
and a substantial fraction of other transuranics all undergo fission
to produce power. The composite used fuel is a mixture of uranium
and transuranic elements. Pyrometallurigical processing then
separates the uranium which can be reused.
8. Pyrometallurgical processing
Pyrometallurgical processing extracts a mix of transuranic
elements from used fuel and not the pure plutonium that PUREX
reprocessing separates. This has advantages in a counter-proliferation sense since plutonium-239 is not easily separated from other
transuranic elements and that poisons potential weapon manufacturing. Pyrometallurgical processing is based on electroplating
to collect metal extracted as ions from a chemical bath.
The process is illustrated in Fig. 4. Spent fuel elements are placed in
the anode basket and dissolved in a chemical bath. Pure uranium
collects on the solid cathode, while a mixture of transuranic (TRU)
elements, uranium, and rare earth (RE) fission products deposit on the
Fig. 4. Pyroelectric refining of nuclear waste.
liquid cadmium cathode. That mixture can be burned in fast reactors
after further processing. Other fission products distribute between the
salt and cadmium phases according to the solubility of their chlorides.
Basic pyrometallurgical processes have been developed both in
the U.S. and Russia. The U.S. process produces metallic uranium
whereas the Russians produce uranium oxide. Both processes have
been demonstrated on a pilot plant basis but full production
requires extensive development. Although advantageous in theory,
they cannot substitute for the near-term need to permanently store
open-cycle wastes that have already been and continue to be
extensively accumulated.
9. Vitrifying nuclear waste
Vitrification (glass encasement) is the preferred technique
to contain and dispose of residual actinides from PUREX reprocessing and pyrometallurgic refining. It is an important process for
reducing the volume and minimizing the contamination risks of
high-level nuclear wastes. Vitrification containers are suitable for
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M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
long-term storage in below ground facilities like Yucca Mountain.
Several countries have already vitrified high-level waste and others
are studying the technology. They include the U.S., France, U.K.,
Germany, Belgium, Japan, Russia, and India.
A typical vitrification process is illustrated in Fig. 5.
10. Self-contained, highly depleted nuclear waste
An alternative to reprocessing or refining is to produce a variety
of waste that is self-contained, depleted to the point where it is not
a proliferation problem and storable in underground sites without
concerns about water leaching or seismic damage. TRISO-fueled
reactors provide that capability (Schaffer, 2007). TRISO (tri-structural isometric) fuel is the enabling technology for an advanced
class of reactors with two major variants. One variant, called a
pebble bed reactor, permits a continuous fuel loading/unloading
process. The second employs TRISO fuel in annular prismatic blocks
that are unloaded and replaced after a suitable burn-up period.
(The first variant is closed cycle and the second is open cycle.)
A pebble-bed nuclear reactor is currently operating in China while
TRISO reactors in prismatic configurations are operating in Japan
and Russia. Pebble Bed reactors are also being considered by the
DOE for further development in the U.S.
Fig. 6 displays the design of pebble bed TRISO fuel. The fuel
consists of enriched uranium ( 8%) or thorium kernels each of
which is coated successively with layers of porous carbon, silicon
carbide, and pyrolytic carbon. The layers create a barrier against
fission product release while permitting the transfer of neutrons
and heat energy. In the pebble bed variant, the fuel kernels, each
about 1 mm in diameter, are embedded in a 50-mm graphite
(spherical) pebble. Each fuel pebble contains about 15,000 kernels
and a typical reactor contains several hundred thousand pebbles.
The spent fuel in a TRISO-fueled plant has favorable attributes
from both a storage and non-proliferation point of view. The spent
pebbles are safe to store without cooling, and are impervious to
water leaching. Although there is a small buildup of plutonium239, it is highly diluted with other plutonium isotopes in a difficultto-separate mixture that does not permit a useable explosive
device. The principal component of the spent fuel is uranium238 oxide. Also present is a mixture of actinides and fission
products, all securely contained. Uranium-235 has been depleted
to a level less than that of natural uranium and the spent pebbles
are considered safe for underground storage. It has also been
suggested that they can be disposed of on deep ocean floors
without concern.
11. Risk analysis
Risk is a core issue for nuclear waste disposal. Risk is frequently
cited by critics as the key rationale for stopping further commercial
Fig. 5. Exemplar vitrification design (Penrice, 2008).
0.92-mm
coated particle
Silicon carbide barrier coating
Pyrolytic coating
60-mm
fuel speres
Inner pyrolytic coating
Porous carbon buffer
0.5-33 fuel kernel
Coated particles
embedded in
graphite mix
0.5-mm fuel
kernel Uranium
dioxide
5-mm
graphite layer
Fig. 6. TRISO fuel design.
M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
nuclear reactor construction. Nuclear waste disposal risk can be
broken down systematically as follows:
Terrorist attack of dry cask storage at plant site
The most effective attack would be with shaped charge weapons. Terrorists would have to penetrate to within 50 m of the
casks, through plant security, and deliver the weapons with
rocket or recoilless rifle fire. Alternatively, they could attack
with indirect fire weapons albeit with less accuracy. Since the
waste is encased in steel and concrete, the worst case is that
radioactive materials would be dispersed within a few meters of
the impacted casks. No explosion would occur. The shaped
charge jets would penetrate into the cask interiors and produce
an internal shock wave. The risk would be borne by people living
near the plant but the probability of radioactive exposure would
be slight-to-zero.
Accident or terrorist attack while transporting casks
Effects are similar to those for on-site attacks. The important
point is that no explosion would occur internal to the casks.
Radioactive dispersal risks are again limited to a few meters and
the probability of widespread contamination is slight to zero.
Risk of water table contamination while in permanent storage
The purpose of storage in sites like Yucca Mountain is to
minimize water table and other external contamination for
periods of 100 years or so. The DOE has spent billions of dollars
analyzing these risks and they are vanishingly small. It is
assumed the facility will be guarded against terrorist attack.
This is significantly less difficult than protecting several hundred nuclear plants. In 100 years or so, the situation can be
revisited, but it seems likely that time extensions will be granted
in most cases. Eventually newer technology will emerge. This
may include deep-sea storage, storage in the upper mantle of
the earth, or delivering waste into space toward the sun. For
various reasons, none of these are feasible now, but that may
change.
Risks associated with nuclear materials proliferation
These risks are real but controllable. Under present policy, there
is almost no risk. Plutonium-239 in existing waste is mixed with
Fig. 7. Comprehensive nuclear waste disposal program.
1387
contaminants that make it useless for weapons manufacture.
Uranium-235 is depleted so that it is less than or equal to natural
uranium concentration. The same is true for TRISO waste. The
proliferation risks for full recycling are similar; the uranium235 is extracted and reused as reactor fuel and the residual
transuranics are useless for weapons. Only in the PUREX process
is there a risk of plutonium-239 being stolen or diverted for
weapons manufacture. As previously noted, France and Japan
already use the PUREX process with safeguards for protecting
the plutonium-239. In the U.S., no plutonium-239 is produced as
a result of commercial refining processes, but if it was, the
safeguards could be the same as those for highly concentrated
uranium-235, tritium, and the plutonium-239 deliberately
produced for weapons.
12. Summary
The outline of a comprehensive nuclear waste program for the
U.S. is provided in Fig. 7.
A useful program should start with reopening the licensing
process for the Yucca Mountain waste disposal facility, and
investigating the feasibility of expanding its capacity. In addition,
the U.S. should restart one or more PUREX reprocessing plants to
help deal with the surplus of waste materials that Yucca Mountain
cannot cope with. New actinide vitrification facilities should also be
developed.
Concurrently, the search for more permanent storage sites
should continue. Congress should appropriate funds to educate
and assuage concerns that local communities have about nuclear
waste storage. The DOE and NRC should issue guidelines and
promotional materials to induce industry to build new TRISOfueled reactors. Finally, research into innovative technology that
burns nuclear waste should be intensified.
The Obama Administration may have misguided priorities
about commercial nuclear power. Short-shifting the national
nuclear waste storage program appears unwise and subordinated
to political pressures. Specifically, the Yucca Mountain initiative
has been terminated prematurely and defunded, and has been
replaced by a blue ribbon commission to find alternatives. That
approach does not exploit near-term, well-researched technology
for underground storage. It also does not take advantage of wellestablished techniques that are being pursued in Europe and Asia.
Significant capabilities already exist for reducing the amount and
volume of nuclear waste, specifically PUREX reprocessing, vitrification, and TRISO fuel configurations. The U.S. has a long and
successful history in all three, but this is being ignored. Current
opportunities for waste reduction are being overlooked. The
Administration has furthermore not made a serious attempt to
provide incentives to local communities for accommodating waste
storage at new sites. Inevitably, new waste storage sites in addition
to Yucca Mountain will be required. There is historical evidence
that incentives facilitate the process. The Bully Pulpit of the White
House could go a long way toward establishing a successful
incentives program.
Table 2
Comparison of risks with current policy.
Current policy
Yucca Mountain storage
PUREX refining
Full recycling
TRISO fuel
Terrorist attack
Transportation
Water contamination
Proliferation
Magnified by several hundred
Zero to slight
Less than current policy
Zero to slight
Zero to slight
Zero
Finite but slight
Finite but slight
Finite but slight
Essentially zero
Slight for about 100 years
Slight for about 100 years
Slight
Slight
Zero
Essentially zero
Zero
Finite for Pu-239
Essentially zero
Essentially zero
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M.B. Schaffer / Energy Policy 39 (2011) 1382–1388
A qualitative summary of the risks for various nuclear waste
disposal policies is provided in Table 2.
References
Benedict, M., Pigford, T.H., Levi, H.W., 1981. Nuclear Chemical Engineering second
ed. McGraw-Hill, New York.
Hannum, W.H., Marsh, G.E., Stanford, G.S., 2005. Smarter use of nuclear wastes.
Scientific American December, 84–91.
Penrice, C.H., 2008. Vitrification Assistance Program: International Cooperation on
Vitrification Technology. /www.wmsym.org/archives/2008/pdfs/8478.pdfS.
Schaffer, M.B., 2007. Nuclear power for clean, safe, and secure energy independence.
Foresight 9 (6), 47–60.
