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NRC proposed rule for licensing reactors authorized by DOE, DOD
Nuclear reactor designs approved by the Department of Energy or Department of Defense could get streamlined pathways through the Nuclear Regulatory Commission’s commercial licensing process should applicants wish to push the technology into the civilian sector.
A proposed rule introduced April 2 by the NRC would “improve NRC licensing review efficiency, where applicable, by explicitly establishing by regulation an additional means for reactor applicants to demonstrate the safety functions of their reactor designs, and thus, would contribute to the safe and secure use and deployment of civilian nuclear energy technologies.”
David J. Loaiza, Rene Sanchez
Nuclear Science and Engineering | Volume 145 | Number 2 | October 2003 | Pages 256-266
Technical Paper | doi.org/10.13182/NSE03-A2381
Articles are hosted by Taylor and Francis Online.
The basic characteristics of waste materials such as silicon dioxide, aluminum, and iron fueled with highly enriched uranium (HEU) and moderated and reflected by polyethylene were investigated. These critical experiments were performed at the Los Alamos Criticality Experiments Facility. The primary intention of these experiments is to provide supplementary data that can be used to validate and improve criticality data for the Yucca Mountain and the Hanford Storage Waste Tanks Projects. The secondary intention of the 2×2 experiments is to reduce the H/U ratio and increase the waste material/U ratio from previously published experiments. These experiments were designed to supply data for interlaced waste material/fuel/moderator systems on the thermal region. The experiments contained silicon dioxide (SiO2), aluminum (Al), and iron (Fe) mixed with 93.23% enriched uranium and moderated and reflected by polyethylene. This analysis systematically examines uncertainties associated with the critical experiments as they affect the calculated multiplication factor. The systematic analysis is separated into uncertainties due to mass measurements, uncertainties due to fabrication, and uncertainties due to composition. Each type of uncertainty is analyzed individually, and a total combined uncertainty is derived. The SiO2-HEU experiment had a measured keff of 0.993, the Al-HEU experiment had a measured keff of 0.990, and the Fe-HEU experiment had a measured keff of 1.000. The calculated keff values tend to agree well with the experimental values. The sensitivity analysis of these critical experiments yielded a total combined uncertainty on the measured keff of ±0.0044 for SiO2, of ±0.0048 for Al, and of ±0.0046 for Fe.
