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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.
G. T. Yeh, T. Tamura
Nuclear Science and Engineering | Volume 82 | Number 2 | October 1982 | Pages 206-219
Technical Paper | doi.org/10.13182/NSE82-A28702
Articles are hosted by Taylor and Francis Online.
Geohydrochemical factors that affect the transport of low-level wastes in saturated-unsaturated porous media are described. Depending on the availability of those geohydrochemical parameters and the detail of information desired, three levels of analyses can be undertaken. Two examples used to illustrate these three levels of analyses are the seepage pond problem and the shallow trench burial problem. The former example indicates that the lower level of resolution gives the more conservative estimate of the breakthrough time for the contaminant. The latter example exemplifies the cases that simple levels of resolution are not adequate nor possible because the flow variables and parameters cannot be determined with rational assumptions. The level 1 model can best be used for screening purposes while level 2 analysis can be employed to rank the alternative sites. Level 3 models should be used for detailed studies of the impact of the chosen site or for predictive assessment of operational sites and decomission scenarios.