Nuclear Wastes Technologies for Separations and Transmutation (1996) / Chapter Skim
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6 ANALYSIS OF THE ISSUES
6 ANALYSIS OF THE ISSUES
Pages 99-128
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From page 99... ...
The waste going to repositories would have less thermal power, would contain a reduced quantity of certain isotopes, and could be incorporated in waste forms with good integrity. These separated species would then be recycled in an ongoing fuel cycle of additional reactors and maintained at constant inventory per reactor until ultimately reduced in quantity in a possible phase-out of nuclear power.
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From page 100... ...
The fast fluxes in the advanced liquid-metal reactor systems would primarily affect the magnitude of and consequently, the hazards related to the TRUs. Since the separated TRUs would remain in the operating fuel cycle, potential releases from human intrusion could be reduced.
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From page 101... ...
, TRUs could be continuously recycled to provide almost constant control of their inventory and material condition within the fuel cycle. Until that time when ALMRs are discontinued, requiring disposal of their inventory of TRUs in a geologic repository, only the fission products and secondary wastes in the resulting waste stream will need to be disposed.
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From page 102... ...
TRANSPORTATION-RELATED ISSUES Transportation of nuclear materials such as spent fuel and other wastes is the aspect of the nuclear fuel cycle that is the most visible to the public and touches them most closely. This section evaluates the impacts by S&T on nuclear material transportation.
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From page 103... ...
As a consequence, the regulatory structure required for the design and certification of radioactive material transportation packages for S&T scenarios is already in place, and it does not appear that significant modifications would be necessary. Conclusions The technology and regulations required to transport materials in an S&T fuel cycle are available unless extended recycle of actinides in thermal reactors were to occur.
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From page 104... ...
Nuclear Nonproliferation and the Once-Through Fuel Cycle Each of the declared nuclear weapon nations the United States, the United Kingdom, and the former Soviet Union, followed later by France and China~reated large dedicated programs for the production of the fissionable weapon materials, as well as civil programs to develop nuclear technology for electric power production and medicine. As many nations began nuclear research and development pro~rams.
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From page 105... ...
That concern was addressed by a combined political-technical barrier, called international safeguards, instituted by the IAEA as an essential part of its responsibilities.S Thus, the LWR became the world standard for nuclear power and, as time passed, the oncethrough fuel cycle became the nonproliferation standard for the United States and many other nations. The Nuclear Nonproliferation Treaty (NPT)
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From page 106... ...
intention to give nonproliferation greater priority in diplomacy and in consideration of regional security and economic matters, to seek to promote nonproliferation efforts, and to make nonproliferation an integral part of its relations with countries around the world. The policy reinforces the use of the LWR once-through fuel cycle and discourages any S&T undertaking that uses spent LWR fuel in the United States for the foreseeable future.8 8 S&T requires spent nuclear power reactor fuel reprocessing which has weapons proliferation implications and hence is of international concern.
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From page 107... ...
For S&T systems, the terrorist scenarios present few features not raised in discussions during the evaluation by the International Nuclear Fuel Cycle Evaluation Group (1980~. At that time, governments expressed confidence that terrorist attacks could be deterred or be resisted as necessary.
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From page 108... ...
This would give about 4 x 10 - cancers/person-rem for the collective dose-risk coefficient for the case considered here. Health Elects of Fuel Cycles Various studies in recent years have quantified the health effects of various nuclear fuel cycles.
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From page 109... ...
Population per GWe-year for the Once-Through LWR Fuel Cycle, Assuming 1,000-Year Dose Commitments Occupational Mortality General Public Injury and Disease Mortalities Total General Total Injury Radiological Nonradiological (radiological) Mortality Occupational Public and Disease Uranium mining Uranium milling UFO conversion Enrichment Fuel fabrication Power generation Transportation Reprocessing Waste management Catastrophic accident Total 0.081 0.012 0.001 0.002 0.054 0.12 0.001 0.025 <0.001 <0.001 <0.00 1 <0.00 1 0.01 0.01 a a a 0.271 0.045 0.105 0.217 0.076 <0.001 <0.001 0.028 0.061 0.008 0.1 0.595 0.211 0.239 0.077 -0.002 0.054 0.158 0.072 0.008 a 0.1 0.921 3.47 2.64 a a a 5.0 0.17 a 0.083 0.168 <0.001 0.002 0.06 0.10 a 0.016 a 11.28 0.429 3.55 3.81 0.001 0.002 5.1 0.17 0.016 0.15 11.8 aThese values are not currently available, but they are expected to be small relative to those presented.
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From page 110... ...
Mining Milling Conversion Enrichment Fabrication Reactor Transportation Waste Accident Reprocessing Total 0.2lc o.os6 <0.001 <0.001 <0.001 0.002 0.005 na na o 0.105 0.217 0.076 <0.001 <0.001 0.028 0.061 0.008 0.1 o 0.27 0.60 0.083 0.172 0.061 <0.001 <0.001 0.028 0.027 <0.001 0.1 0.068 0.54 aThe values from National Council on Radiation Protection and Measurements (1987) have been multiplied by a risk coefficient of 0.04 cancer fatalities pr-Sv (4 x 10-4 cancers/pr-rem)
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From page 111... ...
However, for the reactor-based cycles and the once-through cycle with good information bases, the total radiation exposure of the general public from the entire nuclear fuel cycle is very small. An ORNL report estimates that for the LWR oncethrough fuel cycle the mortality rate from fatal cancers among the general U.S.
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From page 112... ...
To furnish TRUs for starting a transmutation reactor, the new reprocessing plant for highyield recovery of all actinides from spent LWR fuel would have to begin operation well in advance of the first commercial transmutation reactor.~° For example, DOE's ALMR program proposes a centralized commercial facility capable of reprocessing 2,700 Mg/yr of LWR spent fuel. It could supply the actinides for the annual introduction of one 1.4 GWe ALMR.
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From page 113... ...
Relative Economics of Reprocessing versus Once-Through Fuel Cycle for LWRs Since all of the transmutation concepts would involve reprocessing and recycle of actinides from LWR spent fuel, it is instructive to examine the cost of conventional aqueous reprocessing to recycle uranium and plutonium in the LWR fuel cycle, even neglecting the expected higher cost of highyield recovery and recycle of all the actinides as proposed by the transmutation concepts. A recent study of LWR fuel-cycle costs by the Nuclear Energy Agency (NEA)
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From page 114... ...
Utility Financing The rationale for utility ownership of a project requiring both a special-purpose, non-LWR reactor technology to transmute radionuclides and an integrated fuel reprocessing plant based on first-of-a-kind, nonproven technology is difficult to understand. The Nuclear Waste Policy Act of 1982 essentially relieves utilities of the responsibility for postirradiation processing and permanent disposal of spent fuel.
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From page 115... ...
Financing For this study unit reprocessing costs were calculated for a conventional aqueous reprocessing plant with an annual throughput of 900 Mg/yr, if owned by the government, utilities, or by private industry. An overall capital cost of $5,370 million was adopted, based on the new THORP facility, as shown in Table 6-7.
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From page 116... ...
Even lower estimates of capital costs were presented earlier by the ALMR project (Salerno et al., 1989) for PUREX/ TRUEX reprocessing plants designed for high-recovery yield of all TRUs from LWR spent fuel.
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From page 117... ...
117 comparisons with published reprocessing prices and with other estimates of reprocessing costs are given in Appendix J Summary Costs of contemporary aqueous reprocessing plants in the United Kingdom, France, and Japan are important benchmarks to compare with U.S.
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From page 118... ...
These changes greatly increased costs and prolonged construction schedules for many nuclear facilities, and in some cases, provoked outright cancellation. Requirements were changed at the regulatory level (e.g., retrofits to reactor safety systems and the West Valley Fuel Reprocessing Plant)
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From page 119... ...
Moreover, the operation of an S&T cycle is certain to be more expensive than the once-through fuel cycle, until the price of uranium fuel makes the actinides from LWR fuel an economical substitute fuel source (which is many decades in the future)
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From page 120... ...
If any one of the components of the system cannot be developed, licensed, and operated with reasonably high reliability, the desired benefits will be foreclosed. Implementation of S&T technology would require the construction and licensing of the following four new types of fuel-cycle facilities in addition to those currently used or planned for a once-through LWR fuel cycle: · LWR fuel reprocessing: One or more large plants would be required to receive LWR spent fuel, reprocess it to recover the radionuclides to be transmuted, and treat wastes in preparation for transportation and disposal.
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From page 121... ...
The NRC radiation protection standards (lOCFR20) apply, as do the EPA nuclear fuel-cycle standards (40CFR190)
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From page 122... ...
and special nuclear material (lOCFR70~. They are also subject to NRC radiation protection standards (lOCFR20)
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From page 123... ...
Even though the regulatory definition looked as though it might 123 encompass accelerators, it had been written more expansively than the statutory definition in order to encompass reprocessing facilities that, although they do not produce special nuclear material anew, do separate it into a usable form and therefore could be said to "produce" it. The AEA defines a utilization facility as "any equipment or device, except an atomic weapon, determined by rule of the Commission to be capable of making use of special nuclear material in such quantity as to be of significance to the common defense and security, or in such manner as to affect the health and safety of the public, or peculiarly adapted for making use of atomic energy in such quantity as to be of significance to the common defense and security, or in such manner as to affect the health and safety of the public ...." NRC regulations, however, currently limit the definition of a utilization facility to "any nuclear reactor other than one designed or used primarily for the formation of plutonium or 233U." Whether an accelerator used to transmute waste would be considered a utilization facility hinges on whether neutron bombardment of the waste material would produce heat used to generate power.
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From page 124... ...
. yielded in or made radioactive by exposure to the radiation incident to the process of producing or utilizing special nuclear material....
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From page 125... ...
Civilian Reactor Spent Fuels It should be recognized at the outset that S&T (i.e., enhanced recovery and destruction of selected radionuclides) is inextricably intertwined with standard spent-fuel reprocessing.
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From page 126... ...
The amount of radionuclides relative to that in LWR spent fuel is simply too small to justify such an effort. Research and development for Hanford, Savannah River, and Oak Ridge can be coordinated and shared, and the longer-term research component should benefit all those sites.
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From page 127... ...
1992. Impact of Actinide Recycle on Nuclear Fuel Cycle Health Risks.
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