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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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Findings of the ANS Executive Order Expert Advisory Group
On May 23, President Donald Trump signed four Executive Orders (EOs) designed to “usher in a nuclear energy renaissance” by building on federal policies and programs and directing efficiencies in the licensing, siting, development, and deployment of advanced reactor technologies.
In order to evaluate the specific proposals contained in the EOs, a group of experts was convened from various sectors of the U.S. nuclear technology enterprise, under the auspices of the ANS External Affairs Committee, to compare the EOs against existing ANS board-approved Position Statements and to offer constructive input for subsequent implementation by the Trump administration.
The group’s findings and feedback, which were delivered by ANS CEO Craig Piercy to ANS President Lisa Marshall and the Board of Directors, are listed below, grouped by individual EO.
Chih-Tien Liu, Hund-Der Yeh
Nuclear Technology | Volume 143 | Number 3 | September 2003 | Pages 322-334
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT03-A3420
Articles are hosted by Taylor and Francis Online.
This paper is to study the effects of fracture width on the transport of a radionuclide in a multiple and parallel fractured rock formation. The equation describing the transport of the radionuclide released from the geological repository includes the following mechanisms: advection, dispersion, radioactive decay, and adsorption on the fracture surfaces. The concentration at the inlet of each fracture is assumed constant. An analytical solution was derived based on such a mathematical model by the Laplace transform technique. The solution indicates that identical concentration distributions can be observed in each fracture of the equal-width parallel fractured system. In an unequal-width fractured system, the penetration distances along wide fractures are generally larger than that in a single uniform fractured system. The radionuclide concentration in the wide fracture quickly reaches source concentration in the near-field environment, confirming that the fracture width plays an important role in radionuclide transport through a system of multiple and parallel fractured media.
