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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Oklo completes end-to-end demonstration of advanced fuel recycling
Oklo Inc. has announced that it has completed the first end-to-end demonstration of its advanced fuel recycling process as part of an ongoing $5 million project in collaboration with Argonne and Idaho National Laboratories. Oklo’s goal: scaling up its fuel recycling capabilities to deploy a commercial-scale recycling facility that would increase advanced reactor fuel supplies and enhance fuel cost effectiveness for its planned sodium fast reactors.
Dwayne A. Chesnut
Nuclear Technology | Volume 104 | Number 2 | November 1993 | Pages 182-192
Technical Paper | Special Issue on Waste Management / Radioactive Waste Management | doi.org/10.13182/NT93-A34882
Articles are hosted by Taylor and Francis Online.
Waste packages for a U.S. nuclear waste repository are required to provide reasonable assurance of maintaining substantially complete containment of radionuclides for 300 to 1000yr after closure and of permitting only controlled release of radionuclides for 10000 yr. The waiting time to failure for complex failure processes affecting engineered or manufactured systems is often found to be an exponentially distributed random variable. Assuming that this simple distribution can be used to describe the failures of hypothetical singlebarrier waste packages, bounding calculations show that the mean time to failure would have to be >107 yr in order to provide reasonable assurance of meeting this requirement. If such a waste package could be manufactured, it would be practically impossible to demonstrate its performance within the repository preclosure time of 40 yr. With two independent barriers, each would need to have a mean time to failure of only 105 yr to provide the same reliability, illustrating that the use of redundant independent barriers is the key to both achieving and demonstrating regulatory compliance. However, even this demonstration would require testing tens of thousands of two-barrier systems for several decades. As more barriers are added, the mean lifetime required of each individual barrier decreases, and the demonstration of performance becomes more feasible, although still requiring extensive testing and observation during the preclosure period for performance confirmation. In any case, the results illustrate that neither the engineered barrier system nor the geologic barrier system alone is likely to provide the required degree of assurance of repository safety.