Nov. 30, 2018


Independent Reviews, Environmental Assessments Needed to Build Trust and Inform DOE NNSA’s Plans if it Proceeds with the Dilution and Disposal Process of Surplus Plutonium

WASHINGTON – If the dilute and dispose approach for disposing of the surplus plutonium in the Waste Isolation Pilot Plant (WIPP) is fully implemented, the U.S. Department of Energy (DOE) should use two independent review teams to develop public trust in and improve its decisions, says a new interim report by the National Academies of Sciences, Engineering, and Medicine. The first team is a re-initiation of an independent review organization representing the concerns of the state of New Mexico, where WIPP is located, and the second is a separate independent team that would review the classified aspects of DOE’s conceptual plan as they are developed for Congress.

This report is the first of two in a congressionally mandated study evaluating the general viability of the DOE National Nuclear Security Administration’s (NNSA’s) conceptual plan for disposing of 34 metric tons of surplus plutonium in WIPP – a proposal  under the Plutonium Management and Disposition Agreement (PMDA) signed by the U.S. and Russian Federation in 2000 and revised in 2010.  WIPP is a DOE facility located outside Carlsbad, New Mexico, designed to safely isolate defense-related transuranic waste. NNSA’s dilute and dispose plan states that the diluted plutonium would meet the criteria for disposal at WIPP as defense-related transuranic waste. The dilution process of the surplus plutonium will be carried out at DOE's Savannah River Site in South Carolina. 

Congress asked the National Academies to evaluate the feasibility of NNSA’s plans to ship, receive, and place surplus plutonium in WIPP and the agency’s understanding of the impacts of these plans on WIPP.

So far, the dilute and dispose process has been demonstrated at a small scale by DOE’s Office of Environmental Management as it begins to process 6 metric tons of surplus plutonium, a quantity separate from the 34 metric tons.  Due to lack of information, the Academies committee that is conducting the study did not evaluate the DOE’s ability to scale up current infrastructure and processes to address the 34 metric tons or the associated risks of doing so. The report, a preliminary assessment, says the insufficient capacity within WIPP for disposal of 34 metric tons of diluted plutonium is one of several barriers to implementation in NNSA’s conceptual plan.

The dilute and dispose process includes the oxidization of surplus plutonium followed by dry blending with an adulterant to reduce the concentration (weight) of the plutonium.  This blended material is then packaged in a suitable manner for its transport and disposal.  While NNSA says this process meets the intent of the PMDA, the committee said the process is not currently a PMDA-approved method for disposition of U.S. surplus plutonium.

The previous PMDA-approved plan was to incorporate the surplus plutonium into mixed oxide (MOX) fuel to be used in commercial nuclear reactors, essentially making it available as an energy resource.  Even though construction began on the facility at the Savannah River Site in South Carolina to manufacture MOX fuel, substantial schedule delays and cost overruns led to its cancellation this year. 

Since New Mexico will be the recipient of the diluted plutonium waste and the state’s Environment Department will review DOE’s permit modification requests, the committee recommended an independent technical organization  representing concerns of the state be re-initiated, which should increase robustness of DOE plans and strengthen public trust in them. However, the committee said the strategy for developing a National Environmental Policy Act environmental impact statement (EIS) for disposing of this surplus plutonium is unknown.  An EIS is a document prepared by a federal agency if a proposed federal action could significantly affect the quality of human health and the environment.  The report calls for a full programmatic environmental impact statement to be developed that would encompass all sites, transportation, and activities involved in the process.  The statement is important because the amount of surplus plutonium being considered by NNSA’s dilute and dispose plan represents over half of the remaining surplus plutonium in the U.S. and is much larger than amounts previously considered under a supplemental environmental impact statement and would have a larger impact on multiple sites and states. 

The lack of approval from the Russian Federation for using the dilute and dispose option to meet the PMDA requirements is also a barrier, the committee highlighted.  PMDA was signed by both the U.S. and the Russian Federation to convert surplus plutonium into forms unrecoverable for use in nuclear weapons. 

The interim report also includes three sets of follow-up questions for NNSA  –

In the final report of this study, the committee may revisit and modify the findings, conclusions, and recommendations in this interim report based on NNSA’s answers to these questions.

The study was sponsored by the U.S. Department of Energy.  The National Academies of Sciences, Engineering, and Medicine are private, nonprofit institutions that provide independent, objective analysis and advice to the nation to solve complex problems and inform public policy decisions related to science, technology, and medicine.  The National Academies operate under an 1863 congressional charter to the National Academy of Sciences, signed by President Lincoln.  For more information, visit  A committee roster follows.

Riya Anandwala, Media Relations Officer
Andrew Robinson, Media Assistant
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Copies of Disposal of Surplus Plutonium at the Waste Isolation Pilot Plant: Interim Report are available from the National Academies Press at or by calling 202-334-3313 or 1-800-624-6242.  Reporters may obtain a copy from the Office of News and Public Information (contacts listed above). 


Division on Earth and Life Studies
Nuclear and Radiation Studies Board

Committee on Disposal of Surplus Plutonium at the Waste Isolation Pilot Plant

Robert C. Dynes1 (chair)
President Emeritus and Professor of Physics
University of California
San Diego

Lisa M. Bendixen
Vice President
ICF Consulting
Fairfax, Va.

Michael S. Bronzini
Dewberry Chair and Professor Emeritus
Volgenau School of Engineering
George Mason University
Arlington, Va.

George E. Dials (resigned from the committee on September 20, 2018)
Senior Adviser
Board of Directors
Pajarito Scientific Corp.
Santa Fe, N.M.

Leonard W. Gray
Chief Scientist (retired)
E.O. Lawrence Livermore National Laboratory
Livermore, Calif.

Michael R. Greenberg
Dean Emeritus and Distinguished Professor
Edward J. Bloustein School of Planning and Public Policy
Rutgers University
New Brunswick, N.J.

David W. Johnson, Jr.2
Director of Materials Research (retired)
Bell Laboratories
Lucent Technologies
Murray Hill, N.J.

Annie B. Kersting
Director of University Relations and Science Education
E.O. Lawrence Livermore National Laboratory
Livermore, Calif.

M. David Maloney
Technology Fellow, Emeritus
Jacobs Engineering Group

S. Andrew Orrell
Section Head
Waste and Environmental Safety
International Atomic Energy Agency

William C. Ostendorff
Class of 1960 Distinguished Visiting Professor in National Security
Political Science Department
United States Naval Academy
Annapolis, Md.

Tammy C. Ottmer
Program Manager
Nuclear Materials Transportation Oversight
Colorado State Patrol

Cecil V. Parks
Nuclear Nonproliferation Division
Oak Ridge National Laboratory
Oak Ridge, Tenn.

Matthew K. Silva
Independent Consultant
Albuquerque, N.M.


Jennifer Heimberg
Staff Officer

1Member, National Academy of Sciences
2Member, National Academy of Engineering