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.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Feb 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
March 2026
Nuclear Technology
February 2026
Fusion Science and Technology
January 2026
Latest News
Fluor to serve as EPC contractor for Centrus’s Piketon plant expansion
The HALEU cascade at the American Centrifuge Plant in Piketon, Ohio. (Photo: Centrus Energy)
American Centrifuge Operating, a subsidiary of Centrus Energy Corp., has formed a multiyear strategic collaboration with Fluor Corporation in which Fluor will serve as the engineering, procurement, and construction (EPC) contractor for Centrus’s expansion of its uranium enrichment facility in Piketon, Ohio. Fluor will lead the engineering and design aspects of the American Centrifuge Plant’s expansion, manage the supply chain and procurement of key materials and services, oversee construction at the site, and support the commissioning of new capacity.
Robert W. Rice, John C. Walton
Nuclear Technology | Volume 163 | Number 1 | July 2008 | Pages 15-23
Technical Paper | High-Level Radioactive Waste Management | doi.org/10.13182/NT08-A3965
Articles are hosted by Taylor and Francis Online.
A numerical experiment was performed in order to examine the ability of multiple Monte Carlo realizations of a numerical model to reproduce the risk from a hypothetically known waste disposal situation. In the analysis, the risk was summarized by several risk metrics that could be chosen by a regulatory agency to set a risk standard. In the numerical experiment, the parameters in the numerical model are systematically varied to adjust bias (conservative or nonconservative) and to increase uncertainty relative to the hypothetically known future. The influence of parameter bias and uncertainty on the accuracy of each risk metric in predicting the nominal risk was evaluated and presented graphically. These analyses concluded that the peak-of-the-mean metric provides the least stable and least accurate risk predictions, whereas the cumulative release metric and mean of the peaks are more stable and accurate. The peak-of-the-mean and peak-of-the-median metrics exhibit risk dilution (i.e., a decrease in the predicted risk with increased uncertainty) and tend to underpredict risk. Additionally, these results illustrated how risk predictions that are made using what may be considered "conservative" assumptions can be moved in a direction that may or may not be expected or intended. Simulation relative to a hypothetical future (i.e., the nominal case) provides insight into the numerical behavior and potential accuracy of our risk assessment tools and potential issues with setting regulatory standards.