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
May 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
June 2026
Nuclear Technology
Fusion Science and Technology
Latest News
Getting back to yes: A local perspective on decommissioning, restart, and responsibility
For 45 years, Duane Arnold Energy Center operated in Linn County, Ia., near the town of Palo and just northwest of Cedar Rapids. The facility, owned by NextEra Energy, was the only nuclear power plant in the state.
In August 2020, a historic derecho swept across eastern Iowa with winds approaching 140 miles per hour. Damage to the plant’s cooling towers accelerated a shutdown that had already been planned, and the facility entered decommissioning soon after, with its fuel removed in October of that year. Iowa’s only nuclear plant had gone off line.
Today the national energy landscape looks very different than it did just six short years ago. Electricity demand is rising rapidly as data centers, artificial intelligence infrastructure, advanced manufacturing, and electrification expand across the country. Reliable, carbon-free baseload power has become increasingly valuable. In that context, Linn County has approved the rezoning necessary to support the recommissioning and restart of Duane Arnold and is actively supporting NextEra’s efforts to secure the remaining state and federal approvals.
John Avis, Nicola Calder (Geofirma Eng Ltd), Erik Kremer (NWMO)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 363-370
The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management, the federally-approved plan for the safe long-term management of Canada’s used nuclear fuel. Under this plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable host rock formation.
The NWMO completed an assessment of postclosure safety for a conceptual repository constructed at a depth of 500 m below ground surface (mBGS) in a hypothetical sedimentary rock setting in Southern Ontario, Canada. The Normal Evolution Scenario considered in that assessment postulates the release of radionuclides from defective containers and subsequent transport to the biosphere via a water supply well. Transport simulations were performed using constant climate conditions and a steady-state groundwater flow geosphere. Results indicate that doses from these postulated releases would be many orders of magnitude below the regulatory limit.
This paper presents results from a follow-up study which considers the impact of glaciation on transport, evaluating a large number of sensitivity cases for geosphere parameters, processes, and boundary conditions. Sensitivity cases are compared using transient system performance over a 1 million-year simulation period. A “snapshot” Mean Life Expectancy (MLE) approach is developed where MLE calculations are performed at 500-year intervals by assuming the flow system is constant at those times. MLE statistics from across the repository footprint are presented. Time-series results from minimum “snapshot” MLE calculations provide a useful data set for effective comparisons of temporal effects over the 1 million-year simulation period. Summary statistics provide useful comparisons of sensitivity cases.
