ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Won-Jin Cho, Jae-Owan Lee, Pil-Soo Hahn, Kwan-Sik Chun
Nuclear Technology | Volume 116 | Number 1 | October 1996 | Pages 115-126
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT96-A35316
Articles are hosted by Taylor and Francis Online.
Radionuclide release from an engineered barrier in a low- and intermediate-level waste repository is evaluated. The results of experimental studies conducted to determine the radionuclide diffusion coefficients and the hydraulic conductivities of calcium bentonite and crushed granite mixtures are presented. The hydraulic conductivity of the mixture is relatively low even at low dry density and clay content, and the principal mechanism of radionuclide migration through the mixture is diffusion. The measured values of apparent diffusion coefficients in calcium bentonite with a dry density of 1.4 Mg/m3 are of the order of 10-13 to 10-12 m2/s for cations and 10-11 m2/s for iodine. These values are similar to those in sodium bentonite. The radionuclide release rates from the engineered barrier composed of the concrete structure and the clay-based backfill were calculated. Carbon-14 and 99Tc are the important nuclides; however, their maximum release rates are <10-5 GBq/yr. To quantify the effect of uncertainties of input parameters on the radionuclide release rates, Latin Hypercube sampling was used, and the ranges of release rates were estimated statistically with a confidence level of 95%. The uncertainties of the assessment results of the radionuclide release rate are larger in the case of the sorbing nuclides such as 137Cs. Finally, the sensitivity of the input parameter to release rate is also evaluated.
