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Facility design can aid or frustrate international safeguards efforts.
There has been considerable enthusiasm and promise for a nuclear renaissance, but the renaissance can only occur if there is public confidence in nuclear power. A crucial part of the effort to expand nuclear power in the United States and other technologically advanced states—and introduce nuclear power to developing states—will be the “3S” concept: safety, security and safeguards.
The nuclear power industry’s emphasis on safety has resulted in a strong safety record, while the Sept. 11 terrorist attacks in the U.S. focused industry concern on facility plant security. Safeguards, the final piece of the puzzle, have domestic and international dimensions. An efficient and cost-effective method of applying safeguards is by using the “Safeguards by Design” approach.
A nuclear facility must manage and control its nuclear material to satisfy both national laws and regulations on the use and accountancy of nuclear materials and international obligations on the peaceful use of nuclear power by the International Atomic Energy Agency (IAEA). Because I was an IAEA safeguards inspector and an engineer, this article will describe safeguards in terms of the goal of the international safeguards technical objectives.
The IAEA states that the technical objective of safeguards is “the timely detection of diversion of significant quantities of nuclear material from peaceful nuclear activities to the manufacture of nuclear weapons or of other nuclear explosive devices or for purposes unknown, and deterrence of such diversion by the risk of early detection.” All IAEA safeguards activity should attempt to fulfill that safeguards technical objective.
The IAEA’s use of nuclear materials accountancy to verify the material independently of state and operator is the key part of this effort. Containment and surveillance of nuclear material and the state’s and operator’s facility activities provide complementary measures to supplement verification of the accountancy.
If it proves difficult to measure nuclear materials, especially bulk nuclear materials such as plutonium being reprocessed or uranium being enriched, to the accuracy desired, containing the material by tamper-indicating seal or monitoring the material by radiation detectors or cameras may provide assurance that material has not been diverted. The effort, both in inspector labor and technology development and deployment, can depend on the complexity of a facility type and the ease of applying the desired safeguards measures.
Because the design of the facility, including the processes and physical layout, can facilitate or frustrate IAEA safeguards efforts, the IAEA and states attempting to fulfill their safeguards obligations have conceived and promoted the concept of safeguards-by-design, where the operator and the IAEA mold the facility design into a format to make the plant friendly to safeguards. Safeguards-by-design has three major benefits: decreasing costs for the oversight agency, improving safeguards assurances through advanced safeguards and reducing the cost of safeguards implementation to the operator.
At the Rokkasho Reprocessing Plant (RRP) in Aomori, Japan, the Japanese have attempted to make access to the material and to the processes as simple as possible so the IAEA can measure the uranium and plutonium in the reprocessing streams with the desired frequency and accuracy.
The plant is designed so that complementary measures such as containment, surveillance and process monitoring can be applied effectively to provide assurance that no material is removed or introduced to the process without IAEA knowledge. By implementing the safeguards-by-design concept, the RRP decreased costs for the IAEA by reducing inspection hours and making safeguards implementation easier. Improving safeguards assurances through advanced safeguards such as process monitoring and an on-site laboratory for accountancy verification measurements jointly run by the IAEA and the Japanese Nuclear Material Control Centre also decreased costs. By making the application of safeguards part of normal operational costs and a design feature, the operator also benefited with decreased costs.
Safeguards-by-design can also be integrated into plant design after it is complete or even into an existing plant. The IAEA and plant operator can attempt to redesign plant features during construction or facility modifications and modify operations to facilitate safeguards.
We are envisioning this mode of safeguards-by-design while reviewing safeguard approaches for the newer enrichment facilities. Here the operators have a fairly set design and the goal is to “tweak” the design in the construction phase or modify the design of the operations to facilitate best practice safeguards implementation. This is not optimal safeguards-by-design but can be a practical solution.
This is not the same as implementing safeguards at an existing plant, in that there would be more cooperation between the state, the oversight agency such as the IAEA and the operator to make design modifications specifically to facilitate safeguards implementation and to have all parties reap the three major benefits of safeguards by design.
In a Light Water Reactor (LWR), safeguards hinge on knowing the whereabouts of the nuclear fuel assemblies and that plutonium from the spent fuel assemblies is not being diverted into a weapons program. Minor modifications could assist the use of unattended and remote monitoring systems:
The fuel could be designed for ease of inspection by stamping unique identifiers such as serial numbers on it in places easily accessible for inspectors.
The plant could be laid-out so that the number of access paths for diversion could be easily monitored.
Power supplies and data lines to surveillance systems could be easily installed.
Fresh and spent fuel could be tracked moving to and from the spent fuel pool to the reactor vessel.
The greatest hope of safeguards practitioners is to make building-in safeguards the norm for Generation IV nuclear facility designs of the mid-century.
In the future, there is a strong probability advanced Generation IV reactors will actually be built. Generation IV includes high-temperature gas reactors, pebble bed modular reactors, advanced CANDU reactors, sodium-cooled fast reactors, thorium cycle reactors and the so-called cartridge reactors.
This suite of reactors has features such as on-load refueling, lifetime cores, the capability to breed fuels and transmute and burn fission product wastes, and different deployment and physical layouts from today’s plants that will in most cases need advanced safeguards beyond those used in today’s LWRs. It would be desirable for these reactors to make safeguards a part of the design process now.
Furthermore, the next generation of enrichment and reprocessing plants that inevitably will be needed must have safeguards built into them to be able to do a better job than today’s facilities.
In light of the desire to build safeguards into future nuclear power facilities, the National Nuclear Security Administration (NNSA) has created the integrated safeguards-by-design group and a proliferation resistance and risk assessment group. The proliferation resistance group has the task of analyzing various new facility designs and finding intrinsic proliferation resistance features.
The concept of safeguards by design should be seen by power plant operators and other professionals working in the nuclear fuel cycle as the wave of the future. This will be especially true since the international flavor of the nuclear power profession makes the possibility of deploying designs born here in the U.S. very desirable—and probable—in other countries that are non-nuclear weapon states with a strong safeguards obligation.
Even facility designers from a nuclear weapons state such as the U.S. will need familiarity with safeguards. Nuclear power professionals will have to be conversant on the topics discussed in this article if they want to make the “3S” concept an industry standard.
Author: Brian D. Boyer, Ph.D., is the nonproliferation team leader/project leader, International Safeguards Nuclear Nonproliferation Division N-4, Safeguards & Security Group, at Los Alamos National Laboratory in Los Alamos, New Mexico, U.S.A.
Nuclear Power International June, 2009
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