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
Apr 2026
Jan 2026
Latest Journal Issues
Nuclear Science and Engineering
May 2026
Nuclear Technology
February 2026
Fusion Science and Technology
Latest News
NRC proposed rule for licensing reactors authorized by DOE, DOD
Nuclear reactor designs approved by the Department of Energy or Department of Defense could get streamlined pathways through the Nuclear Regulatory Commission’s commercial licensing process should applicants wish to push the technology into the civilian sector.
A proposed rule introduced April 2 by the NRC would “improve NRC licensing review efficiency, where applicable, by explicitly establishing by regulation an additional means for reactor applicants to demonstrate the safety functions of their reactor designs, and thus, would contribute to the safe and secure use and deployment of civilian nuclear energy technologies.”
E. M. Pierce, B. P. McGrail, M. M. Valenta, D. M. Strachan
Nuclear Technology | Volume 155 | Number 2 | August 2006 | Pages 149-165
Technical Paper | Materials | doi.org/10.13182/NT06-A3753
Articles are hosted by Taylor and Francis Online.
To predict the long-term fate of low- and high-level waste forms in the subsurface over geologic timescales, it is important to understand how the formation of an alteration phase or phases will affect radionuclide release from the corroding waste forms under repository-relevant conditions. To generate data to conduct performance assessment calculations for the low-activity waste (LAW) integrated disposal facility at the Hanford Site in southeastern Washington state, accelerated weathering experiments are being conducted with the pressurized unsaturated flow (PUF) test method to evaluate the long-term release of radionuclides from immobilized LAW (ILAW) glasses. The radionuclide release rate is a key parameter affecting the overall performance of the LAW disposal facility.Currently, there are three other accelerated weathering test methods being used to evaluate the long-term durability of glasses: product consistency test, vapor hydration test, and unsaturated drip test. In contrast to these test methods, PUF tests mimic the hydraulically unsaturated open-flow and transport conditions expected in the near-field vadose zone environment, allow the corroding waste form to achieve its final reaction state, and accelerate the hydrolysis and aging processes by as much as 50 times over conventional static tests run at the same temperature.In this paper, we discuss the results of an accelerated weathering experiment conducted with the PUF apparatus to evaluate the corrosion rate of an ILAW glass, LAWAN102, made with actual Hanford waste taken from Tank 241-AN-102 (U). Results from this PUF test with LAWAN102 glass showed that after 1.5 yr of testing, the corrosion rate, based on B release, reached a steady-state release of 0.010 ± 0.003 g m-2 day-1, which is approximately eight times lower than other glasses previously tested. These results indicate that 99Tc is being released from the glass congruently, whereas U is being controlled by the formation of a solubility-limiting phase or phases. These results also highlight the importance of being able to predict, with some level of certainty, the alteration phase or phases that will form and how the formation of these phases may impact the release, retention, and transport of radionuclides from the glass under the hydraulically unsaturated open flow and transport conditions that are expected in the LAW integrated disposal facility.
