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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
Louis B. Freeman, Herbert C. Hecker
Nuclear Science and Engineering | Volume 80 | Number 2 | February 1982 | Pages 338-341
Technical Note | doi.org/10.13182/NSE82-A21437
Articles are hosted by Taylor and Francis Online.
In a thorium-fueled reactor, the conversion of 232Th to 233U involves the intermediate nuclide 233Pa. This isotope has a significant reactivity effect in any thorium reactor, especially one with an important epithermal flux component. The light water breeder reactor, operating in the Shippingport atomic power station, is a 233U-Th reactor with about half the power produced at energies above thermal. The reactivity effect of full-power equilibrium 233Pa has been inferred from critical position measurements and control element reactivity worths to be ∼2.5% Δρ in this reactor, confirming calculational predictions.
