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Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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!
Latest Magazine Issues
Mar 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
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.
2020 ANS Virtual Winter Meeting Plenary Session Appearance
Profile
Marilyn Kray is responsible for leading major initiatives related to current and advanced reactor designs to create growth opportunities that leverage Exelon’s nuclear operations competency. These initiatives include potential acquisition of existing plants, pursuing operational service agreements both domestically and internationally as well as engaging with advanced reactor developers in order to evaluate potential business opportunities and future deployment of the technology.
Marilyn served as President of NuStart Energy Development, LLC an industry consortium formed to develop the process for preparing the Combined Construction and Operating License applications for the first wave of new nuclear plants to be constructed in the US in over 30 years.
Professional History
Marilyn has an in-depth knowledge of the global nuclear industry. She was Vice President of Exelon Nuclear Partners, responsible for international business development and she led Exelon’s Nuclear Acquisition Support and Integration team pioneering the internal processes for due diligence and plant transitions which resulted in the successful completion of the purchases of Three Mile Island, Clinton, and Oyster Creek. More recently, she led the acquisition of the FitzPatrick plant.
She began her career with Exelon in the licensing organization for Peach Bottom Atomic Power Station. Prior to joining Exelon, Marilyn was a Reactor Engineer and Project Manager for the U.S. Nuclear Regulatory Commission (NRC). Marilyn has testified in front of Congress on multiple occasions on the subject of nuclear development in the U.S.
Industry Leadership and Awards
Throughout her career Marilyn has served in leadership roles as Exelon’s representative to the Nuclear Energy Institute (NEI) and the Electric Power Research Institute (EPRI). She was the 2019-2020 President of the American Nuclear Society. Marilyn is the 2005 recipient of the World Nuclear Association (WNA) award for Distinguished Contribution to the Peaceful Use of Nuclear Technology. In 2007 she received the American Nuclear Society’s Utility Leadership Award. Under Kray’s leadership, the NuStart organization was one of four finalists for the 2012 Edison Award.
Education
Kray is a graduate of Carnegie-Mellon University, with a Bachelor of Science degree in Chemical Engineering.
Last modified November 5, 2020, 10:21am EST