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
Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Latest News
El Salvador: Looking to nuclear
In 2022, El Salvador’s leadership decided to expand its modest, mostly hydro- and geothermal-based electricity system, which is supported by expensive imported natural gas and diesel generation. They chose to use advanced nuclear reactors, preferably fueled by thorium-based fuels, to power their civilian efforts. The choice of thorium was made to inform the world that the reactor program was for civilian purposes only, and so they chose a fuel that was plentiful, easy to source and work with, and not a proliferation risk.
Rob P. Rechard, Lawrence C. Sanchez, Holly R. Trellue, Christine T. Stockman
Nuclear Technology | Volume 136 | Number 1 | October 2001 | Pages 99-129
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT01-3
Articles are hosted by Taylor and Francis Online.
Modeling of nuclear criticality was omitted from performance assessment calculations for the Waste Isolation Pilot Plant (WIPP), a repository for waste contaminated with transuranic radioisotopes, located in southeastern New Mexico, based on arguments of low probability and low consequence. Low-probability arguments are presented here. Guidance provided by the Environmental Protection Agency (EPA) - the regulator of WIPP - allowed either qualitative "credibility" arguments or quantitative probability estimates when screening features, events, and processes such as criticality. Although information to quantitatively evaluate the probability of a criticality event was mostly lacking, qualitatively reasoned discussion of the inability to assemble a critical configuration of fissile material was accepted by the EPA. Specifically, after disposal and prior to an inadvertent human intrusion into the repository, there is no credible mechanism to move radioisotopes (and particularly, fissile material) since only small amounts of brine enter the repository, as adequately demonstrated in calculations over the years. An inadvertent human intrusion (an event that must be considered because of safety regulations) might allow a large pressure gradient to move more brine through the repository, but there is still no credible mechanism to counteract the natural tendency of the material to disperse during transport. Unfavorable physical conditions on concentrating fissile material include low initial solid concentration of fissile material, small mass of fissile material transported over 10 000 yr, and insufficient physical compaction; unfavorable hydrologic conditions include the limited amount of brine available to transport fissile material. Unfavorable geochemical conditions on concentrating the fissile radioisotopes include lack of sufficient adsorption and water chemistry conducive to precipitation.