Fiscal Year 2024

Stockpile Stewardship and 

Management Plan

Report to Congress

November 2023

National Nuclear Security Administration

United States Department of Energy

Washington, DC 20585
Department of Energy/National Nuclear Security Administration | November 2023

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Message from the NNSA Administrator

The Department of Energy’s National Nuclear Security Administration’s (DOE/NNSA) largest mission is to 

design, produce, deliver, and certify the Nation’s nuclear stockpile while advancing the scientific, 

technological, and engineering skills that underpin it. Since the Manhattan Project, the talented people

of the nuclear security enterprise have applied unique capabilities to promote U.S. security in an evolving 

global security environment. Today, our nuclear deterrent remains the foundation of the Nation’s 

defense. 

The Fiscal Year 2024 Stockpile Stewardship and Management Plan (SSMP) describes how DOE/NNSA will

maintain and advance the safety, security, reliability, and effectiveness of the U.S. nuclear weapons 

stockpile without underground nuclear explosive testing. The report also details DOE/NNSA’s plans to 

accomplish the program requirements to produce 80 plutonium pits per year; achieve the first production 

units for the W80-4 Life Extension Program (LEP), W87-1 Modification Program, and W93; and continue 

production of the B61-12 LEP and W88 Alteration 370 warheads. Finally, the report examines other key 

activities that support DOE/NNSA’s weapons program, including stockpile modernization, infrastructure 

recapitalization, and science, research technology, and engineering capabilities. The SSMP discusses both 

on-going and planned activities. 

For more than 75 years, the scientific and engineering discoveries of the nuclear security enterprise have 

enhanced our national and global security in the face of changing world conditions. Our greatest asset is

the people of the nuclear security enterprise, whose expertise is the core of the United States’ nuclear 

deterrence. The nuclear security enterprise workforce is comprised of technical experts at the national 

laboratories, production plants, and sites across the country, and a Federal workforce for planning, 

budgeting, management, and oversight. The SSMP discusses efforts to attract and retain a world-class 

workforce to steward today’s deterrent and design the systems of tomorrow.

With continued support from Congress, DOE/NNSA will continue to anticipate future challenges and 

deliver innovative solutions to meet them. Pursuant to statute, this FY 2024 SSMP is provided to: 

The Honorable Patty Murray

Chair, Senate Committee on Appropriations 

The Honorable Susan Collins

Vice Chair, Senate Committee on Appropriations

The Honorable Jack Reed

Chairman, Senate Committee on Armed Services

The Honorable Roger Wicker

Ranking Member, Senate Committee on Armed Services

The Honorable Chair

Subcommittee on Energy and Water Development

Senate Committee on Appropriations 
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The Honorable John Kennedy

Ranking Member, Subcommittee on Energy and Water Development

Senate Committee on Appropriations

The Honorable Angus King

Chairman, Subcommittee on Strategic Forces

Senate Committee on Armed Services 

The Honorable Deb Fischer

Ranking Member, Subcommittee on Strategic Forces

Senate Committee on Armed Services

The Honorable Kay Granger 

Chairwoman, House Committee on Appropriations

The Honorable Rosa L. DeLauro

Ranking Member, House Committee on Appropriations 

The Honorable Mike Rogers

Chairman, House Committee on Armed Services

The Honorable Adam Smith

Ranking Member, House Committee on Armed Services 

The Honorable Chuck Fleishmann

Chairman, Subcommittee on Energy and Water Development, and Related Agencies 

House Committee on Appropriations

The Honorable Marcy Kaptur

Ranking Member, Subcommittee on Energy and Water Development, and Related Agencies 

House Committee on Appropriations

The Honorable Doug Lamborn

Chairman, Subcommittee on Strategic Forces

House Committee on Armed Services 

The Honorable Seth Moulton

Ranking Member, Subcommittee on Strategic Forces

House Committee on Armed Services 
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Should you have any questions or need additional information, please contact Jason Miller, Acting 

Associate Administrator for Congressional and Intergovernmental Affairs, at (202) 586-8368.

Sincerely,

Jill Hruby

Under Secretary for Nuclear Security

Administrator, NNSA
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Message from the Secretary

The Department of Energy’s National Nuclear Security Administration (DOE/NNSA) was established more 

than 20 years ago with the mission to enhance national security through the military application of nuclear 

science and engineering while upholding nonproliferation standards and supporting peaceful uses of 

nuclear technology. Since that time, DOE/NNSA, in close coordination with the Department of Defense,

has successfully maintained a safe, secure, and effective nuclear deterrent without underground nuclear 

explosive testing.

DOE/NNSA’s nuclear deterrence mission remains the cornerstone of our Nation’s security posture. 

Today’s uncertain global security environment and unprecedented threat landscape require the United 

States to maintain a modern nuclear deterrent and a set of flexible scientific, technical, and engineering 

capabilities to support our national security objectives. The Fiscal Year 2024 Stockpile Stewardship and 

Management Plan details DOE/NNSA’s plans to modernize the stockpile; strengthen its capabilities; and 

recapitalize the infrastructure that supports the nuclear deterrent. 

This Administration is committed to a responsive and resilient nuclear security enterprise and fully 

supports continued advancements in science and engineering that underpin our national defense. With 

the continued support of Congress, DOE/NNSA will continue to provide a safe, secure, reliable, and 

effective nuclear deterrent today and into the future. 

Sincerely, 

Jennifer Granholm

Secretary of Energy
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Executive Summary

The Fiscal Year 2024 Stockpile Stewardship and Management Plan (SSMP), including its classified annex,

describes the Department of Energy’s National Nuclear Security Administration (DOE/NNSA) program to

maintain a safe, secure, and effective nuclear stockpile over the next 25 years. DOE/NNSA publishes the 

SSMP annually, either in detailed report form or as a summary, in response to statutory requirements to 

support the President’s Budget Request to Congress for Weapons Activities. This fiscal year (FY) 2024

report describes current and future nuclear security enterprise activities and capabilities funded by the 

Weapons Activities account supporting the Nation’s nuclear deterrent.

In partnership, the Department of Defense (DoD) and DOE/NNSA plan and manage weapons 

modernization needs to meet the nuclear deterrent objectives outlined in the 2022 National Security 

Strategy (White House), the 2022 National Defense Strategy (DoD), and the 2022 Nuclear Posture Review

(DoD, interagency), while incorporating the unique deterrent effects of nuclear weapons into the Nation’s 

integrated deterrence efforts. This SSMP reflects rigorous mapping of nuclear security enterprise 

capabilities to address military requirements and the priorities identified in these strategic documents.

In 2022, DOE/NNSA continued executing its significant program of record, helping to advance the Nation’s 

nuclear security mission through innovative science and technology solutions. For Weapons Activities, 

DOE/NNSA worked to ensure the existing nuclear weapons stockpile’s safety, security, and reliability

without underground nuclear explosive testing and continued to recapitalize infrastructure and advance 

plutonium pit manufacturing and many other production modernization-related activities. 

Additionally, researchers at Lawrence Livermore National Laboratory (LLNL) made a major scientific 

breakthrough by achieving fusion ignition, a feat scientists have been working toward for decades. On 

December 5, 2022, a team at LLNL’s National Ignition Facility conducted the first controlled fusion 

experiment in history to reach ignition, also known as scientific energy breakeven, meaning it produced 

more energy from fusion than the laser energy used to drive it. This accomplishment will provide 

unprecedented capability to support DOE/NNSA’s stockpile stewardship program—which includes 

research to support the U.S. nuclear deterrent without the need for underground nuclear explosive 

testing—and will provide invaluable insights into the prospects of clean fusion energy.

In 2023, DOE/NNSA’s top priority is to deliver on its commitments in a cost-effective manner. DOE/NNSA 

will continue to cultivate transparent, productive, and enduring relationships with interagency partners, 

industrial and academic contributors, international allies and partners, and other stakeholders. By 

leveraging its innovative science and technology capabilities, DOE/NNSA will meet stockpile milestones, 

and maintain a resilient enterprise to meet the geopolitical security challenges of today and tomorrow. 

DOE/NNSA will:

Maintain the Nation’s Nuclear Deterrent’s Safety, Security, and Effectiveness 

With several warhead modernizations underway, DOE/NNSA is executing an unprecedented variety of 

complex component development and production work. Despite the continued challenges imposed by 

the current industrial base environment, such as supply chain challenges, limited vendor options, and 

changing technologies, DOE/NNSA has continued to make significant progress in its modernization 

activities.
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Near-Term and Out-Year Mission Goals:

◼ Deliver the B61-12 gravity bomb.

◼ Deliver the W88 Alteration (Alt) 370 (with a refresh of the conventional high explosives).

◼ Achieve the first production unit of the W80-4 warhead Life Extension Program and maintain

alignment with the Air Force’s Long Range Standoff cruise missile replacement program.

◼ Support initial fielding of W87-0 on Sentinel, formerly known as the Ground Based Strategic 

Deterrent, and advance the W87-1 Modification Program (formerly called the W78 Replacement 

Warhead). Decrease risks to timely delivery of the W80-4, W87-1, and W93 systems.

◼ Develop the W93 warhead, deployed on Mk7 re-entry body, to augment Navy forces with a more 

survivable weapon deployable on the Ohio-class and Columbia-class submarines.

◼ Develop an integrated plutonium pit production strategy to align and streamline complex-wide 

efforts. Provide a continuous and reliable supply of strategic nuclear weapon components and 

the key materials that make up the components, including plutonium, uranium, lithium, tritium, 

and high explosives.

◼ Provide experimental and computational capabilities and be prepared to address and mitigate 

any challenges that arise in the future.

◼ Qualify pit manufacturing processes and technologies to support first production unit and rate 

production.

◼ Identify new production technologies that leapfrog legacy processes and save cost and/or 

schedule for warhead modernization programs, including at least one Nuclear Explosive Package 

component and one non-nuclear component.

Key Accomplishments:

In 2022, DOE/NNSA:

◼ Delivered an initial operational capability (quantity of re-entry Body Assemblies) of W88 Alt 370s 

to the Navy. The updated W88 Alt 370, which can be launched on missiles from Ohio-class 

submarines, will replace older W88 warheads in the stockpile.

◼ Completed the Phase 1 Concept Study for the W93 Program and received Nuclear Weapons 

Council authorization to advance to Phase 2, Feasibility Study and Design Options. The W93 will 

hedge against technical risk in the fielded submarine-launched warheads and over-reliance on the 

W76, allowing the United States to keep pace with future threats.

◼ Executed full-scale production of the B61-12 and met Air Force shipment requirements.

◼ Delivered all scheduled limited life components for the B61, W76, W78, W80, B83, W87, and W88. 

◼ Completed seven tritium extractions at the Savannah River Site (SRS), more than doubling the 

previous record. Base capabilities for multi-system operations and maintenance support were 

sustained to meet all limited life components exchange gas transfer system (GTS) fills and gas 

transfer system Surveillance DOE/NNSA deliverables to DoD.

◼ Conducted surveillance activities for all weapon systems using data collection from flight tests, 

laboratory tests, and component evaluations to assess stockpile reliability without underground 

explosive nuclear testing, which culminated in completion of all annual assessment reports and 

submission of the annual Report on Stockpile Assessments to the President.
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◼ Achieved 100 percent safe and secure transport of nuclear materials and weapons. All shipments 

were completed without compromise or loss of nuclear weapons or components, or release of 

radioactive material.

◼ Completed the first B61-12 GTS loading run and initiated full operation for loading GTS units for 

weapons refurbishment. 

◼ Completed the W87-1 Preliminary Design review and Acceptance Group review, indicating DoD 

accepted the baseline design and its associated plan for certification.

In 2023, DOE/NNSA:

◼ Completed Long Range Standoff/W80-4 warhead joint flight testing and entered Phase 6.4, 

Production Engineering.

◼ Entered Phase 6.3, Development Engineering, for the W87-1 Modification Program after 

completing the Weapon Design and Cost Report in FY 2022

Strengthen Key Science, Technology, and Engineering Capabilities

Nuclear weapons stockpile activities are supported by the technical expertise of DOE/NNSA’s Federal and 

management and operating partner workforces. DOE/NNSA cultivates cutting-edge technical expertise 

in manufacturing, diagnostics, evaluation, and other areas at the plants and sites, and maintains

unparalleled scientific and engineering capabilities at the three national security laboratories(Los Alamos, 

Lawrence Livermore, and Sandia National Laboratories) that execute science-based stockpile stewardship.

Near-Term and Out-Year Mission Goals:

◼ Advance the innovative experimental platforms, diagnostic equipment, and computational 

capabilities necessary to ensure stockpile’s safety, security, reliability, and effectiveness:

– Deploy DOE/NNSA’s first exascale computer and establish a path forward for continued 

leadership in advanced computing while modernizing the nuclear weapons code base.

– Develop a roadmap for advanced inertial confinement fusion and pulsed power.

– Develop an operational enhanced capability (advanced radiography and reactivity 

measurements) for subcritical experiments.

– Quantify and bound the plutonium aging effects on weapon performance over time.

◼ Support an enduring, trusted, strategic, radiation-hardened microsystems supply and expand 

DOE/NNSA partnerships to leverage NNSA expertise and capabilities to address current and 

emerging challenges.

◼ Maintain and upgrade science facilities enabling continued generation of world-leading results.

◼ Maintain and advance state-of-the-art manufacturing technologies supporting production 

operations.

◼ Continue implementing the Stockpile Responsiveness Program to fully exercise the nuclear 

security enterprise’s workforce and capabilities and explore ways to improve processes without 

disrupting current operations.

◼ Nurture Strategic Partnership Programs that support other relevant needs while advancing the 

nuclear security enterprise’s long-term workforce and capabilities.
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Key Accomplishments:

In 2022, DOE/NNSA:

◼ Completed Annual Assessment Cycle 26: The three NNSA laboratory directors certified that the 

stockpile remains safe, secure, and effective, and that underground nuclear explosive testing is 

not required at this time.

◼ Completed seven developmental pit builds at Los Alamos National Laboratory (LANL), exceeding 

goals in metal production, machining, casting, and post-assembly testing. LANL sustained pit 

production activities allowing for stress-testing and identifying future informed modernization 

priorities.

◼ Performed two consecutive experiments using the Z pulsed power facility to measure the dynamic 

response of aged plutonium. These experiments were the first back-to-back plutonium 

experiments on the Z pulsed power facility, which resulted in operational efficiencies and 

returned valuable data for stockpile stewardship. Additionally, gas gun, light source, and 

benchtop experiments on aged plutonium supported the “Assess Lifetimes and Mitigate Aging”

pegpost (Chapter 4), providing data to quantify and bound changes in plutonium properties with 

age.

Ensure an Adaptive Workforce and Resilient Infrastructure

Planning and investing in advanced capabilities, infrastructure, and, most importantly, the workforce are 

critical for achieving nuclear security objectives. DOE/NNSA continues to revitalize the facilities and 

corresponding infrastructure that make up the nuclear security enterprise. These upgrades are necessary 

to create a responsive and resilient enterprise that can meet national security missions today and in the 

future. 

Near-Term and Out-Year Mission Goals:

◼ Achieve key infrastructure recapitalization milestones and improve early-stage and integrated 

infrastructure planning.

– Complete key construction projects to modernize the nuclear security enterprise, the Y-12 

National Security Complex (Y-12) Fire Station, Emergency Operations Center, Electrorefining, 

West End Protected Area Reduction interface projects, and the Sandia National Laboratories 

(SNL) Emergency Operations Center.

– Accomplish key infrastructure project milestones at LANL and SRS to support the plutonium 

pit production mission.

– Complete and communicate an integrated infrastructure priority plan.

◼ Implement enterprise-wide recruitment and retention strategies by incorporating hiring, 

compensation, and benefits flexibilities, and promoting a healthy work-life balance.

◼ Enhance cyber infrastructure and resiliency across the enterprise.

◼ Enable phasing out mission dependency on Building 9212 at Y-12 by relocating the facility’s 

enriched uranium processing capabilities into existing facilities and the Uranium Processing 

Facility and extending key existing facilities’ operational lifetime into the 2040s.

◼ Support long-term actinide chemistry and materials characterization and deliver the Chemistry 

and Metallurgy Research Replacement Project.

◼ Modernize lithium and tritium facilities.
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◼ Increase tritium production by leveraging additional capacity at two commercial power reactors

to meet stockpile needs.

◼ Recapitalize the high explosives and nuclear weapons assembly infrastructure.

◼ Provide new laboratory space and equipment within the U1a Complex at the Nevada National 

Security Site to support the Enhanced Capabilities for Subcritical Experiments portfolio through 

the U1a Complex Enhancements Project and Advanced Sources and Detectors equipment. 

◼ Provide modern office and laboratory spaces to support the world-class workforce needed to 

maintain the nuclear weapons stockpile capabilities.

◼ Reduce the total deferred maintenance, as measured by the replacement plant value, of the 

nuclear security enterprise by not less than 45 percent by 2030.

Key Accomplishments:

In 2022, DOE/NNSA:

◼ Opened the new John A. Gordon Albuquerque Complex. This $169 million, 330,000 square foot 

Leadership in Energy and Environmental Design Gold-certified complex replaces 25 buildings, 

including 1950s military barracks. It will house more than 1,200 employees who provide 

programmatic, technical support, legal, security, procurement, human resources, business, and 

administrative functions that directly support DOE/NNSA’s national security missions. DOE/NNSA 

simultaneously reduced deferred maintenance while providing modern, safer, and more efficient 

working conditions. 

◼ Developed a solution with LLNL to execute High-Fidelity Training and Operations Center plans that 

will modernize training and accelerate the Savannah River Plutonium Processing Facility path to 

full plant operations. 

◼ Completed the Exascale Computing Facility Modernization project at LLNL. The project upgraded 

the electrical and mechanical capabilities of the Livermore Computing Center, which will enable 

the facility to power the first DOE/NNSA exascale system, named El Capitan, and to provide 

exascale-class computing service to LLNL, LANL, and SNL.

◼ Reached a significant milestone in the Uranium Processing Facility project with all buildings being 

fully enclosed, or “in the dry.” The Uranium Processing Facility project is being built in a series of 

seven subprojects. The first four subprojects are complete, which prepared the site for 

construction, provided necessary infrastructure to support construction, commissioned a new 

electrical substation to support the Uranium Processing Facility project and Y-12, and constructed 

the Mechanical Electrical Building with utility equipment and support systems for the two process 

buildings. The remaining three subprojects are under way.
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Fiscal Year 2024 Stockpile Stewardship 

and Management Plan

Table of Contents

Legislative Language ..........................................................................................................................xix

Chapter 1 Overview and Strategic Context for Managing the Nuclear Weapons Stockpile................. 1-1

1.1 Policy Framework Summary ....................................................................................................1-2

1.2 The DOE/NNSA Nuclear Security Enterprise............................................................................1-3

1.2.1 National Security Laboratories..................................................................................1-3

1.2.2 Nuclear Weapons Production Facilities.....................................................................1-4

1.2.3 Nevada National Security Site ...................................................................................1-5

1.3 Introduction to the Nuclear Weapons Stockpile .....................................................................1-5

1.4 Overall Strategy, Objectives, and Prioritization of Weapons Activities...................................1-6

1.5 Partnership with the Department of Defense .........................................................................1-9

1.6 Challenges in Executing the Stockpile Stewardship and Management Plan ...........................1-9

Chapter 2 Stockpile Management ..................................................................................................... 2-1

2.1 Stockpile Sustainment..............................................................................................................2-2

2.1.1 Assessing the Stockpile..............................................................................................2-3

2.1.2 Stockpile Surveillance ................................................................................................2-4

2.1.3 Maintaining the Stockpile..........................................................................................2-6

2.2 Stockpile Major Modernization ...............................................................................................2-7

2.2.1 Phase X Process (Nuclear Weapons Life Cycle) .........................................................2-8

2.2.2 B61-12 Life Extension Program .................................................................................2-9

2.2.3 W88 Alteration 370 Program...................................................................................2-10

2.2.4 W80-4 Life Extension Program................................................................................2-10

2.2.5 W87-1 Modification Program..................................................................................2-10

2.2.6 W93 Program...........................................................................................................2-11

2.2.7 Future Warheads.....................................................................................................2-11

2.3 Weapon Dismantlement and Disposition..............................................................................2-11

2.3.1 Status.......................................................................................................................2-12

2.4 Production Operations...........................................................................................................2-12

2.4.1 Status.......................................................................................................................2-12

2.5 Nuclear Enterprise Assurance................................................................................................2-13

2.5.1 Status.......................................................................................................................2-13

Chapter 3 Production Modernization ................................................................................................ 3-1

3.1 Primary Capability Modernization ...........................................................................................3-1

3.1.1 Plutonium Modernization .........................................................................................3-1

3.1.2 High Explosives and Energetics Modernization.........................................................3-5
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3.2 Secondary Stage Capability Modernization .............................................................................3-9

3.2.1 Uranium Modernization ............................................................................................3-9

3.2.2 Depleted Uranium Modernization ..........................................................................3-12

3.2.3 Lithium Modernization ............................................................................................3-16

3.3 Tritium Modernization and Domestic Uranium Enrichment.................................................3-19

3.3.1 Tritium Modernization ............................................................................................3-19

3.3.2 Domestic Uranium Enrichment ...............................................................................3-23

3.4 Non-Nuclear Capability Modernization .................................................................................3-24

3.4.1 Status.......................................................................................................................3-25

3.4.2 Challenges and Strategies........................................................................................3-27

3.5 Capabilities-Based Investments.............................................................................................3-28

3.5.1 Status.......................................................................................................................3-29

3.5.2 Challenges and Strategies........................................................................................3-29

Chapter 4 Stockpile Research, Technology, and Engineering.............................................................. 4-1

4.1 Strategic Program Goals...........................................................................................................4-2

4.1.1 Stewardship Capability Delivery Schedule ................................................................4-3

4.2 Enduring Drivers for Stockpile Research, Technology, and Engineering .................................4-4

4.2.1 Sustaining and Assessing the Current Stockpile ........................................................4-4

4.2.2 Ensuring the Resiliency of the Future Stockpile ........................................................4-5

4.2.3 Assessing and Qualifying the Deterrent ....................................................................4-5

4.2.4 Developing Modern Materials and Manufacturing Methods ...................................4-5

4.3 Stockpile Research, Technology, and Engineering Elements and Status.................................4-6

4.3.1 Assessment Science...................................................................................................4-6

4.3.2 Engineering and Integrated Assessments ...............................................................4-10

4.3.3 Inertial Confinement Fusion ....................................................................................4-12

4.3.4 Advanced Simulation and Computing .....................................................................4-14

4.3.5 Weapon Technology and Manufacturing Maturation.............................................4-19

4.4 Nuclear Test Readiness..........................................................................................................4-20

Chapter 5 Security............................................................................................................................. 5-1

5.1 Secure Transportation Asset....................................................................................................5-1

5.1.1 Status.........................................................................................................................5-2

5.1.2 Challenges and Strategies..........................................................................................5-5

5.2 Defense Nuclear Security.........................................................................................................5-6

5.2.1 Status.........................................................................................................................5-8

5.2.2 Sustainment Investments..........................................................................................5-8

5.2.3 Challenges and Strategies..........................................................................................5-9

5.3 Information Technology and Cybersecurity...........................................................................5-10

5.3.1 Transformations to Ensure Information Security and Cybersecurity 

Throughout the Nuclear Security Enterprise...........................................................5-11

5.3.2 Information Technology and Cybersecurity Program Elements and Initiatives......5-11

5.3.3 Ongoing NNSA OCIO Activities ................................................................................5-13

5.3.4 Planned NNSA OCIO Activities.................................................................................5-13

5.3.5 Status.......................................................................................................................5-14

5.3.6 Challenges and Strategies........................................................................................5-15

Chapter 6 Infrastructure and Operations........................................................................................... 6-1

6.1 Challenges and Strategies........................................................................................................6-3
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6.2 Infrastructure Planning and Asset Management.....................................................................6-5

6.2.1 Area Planning.............................................................................................................6-6

6.2.2 Weapons Activities Line-Item Planning Integration ..................................................6-6

6.2.3 Critical Decision Acquisition Milestone Process........................................................6-7

6.3 Acquisition ...............................................................................................................................6-8

6.3.1 Programmatic Construction ....................................................................................6-10

6.3.2 Mission Enabling Construction ................................................................................6-21

6.3.3 Other Acquisition Efforts.........................................................................................6-25

6.4 Modernization Through Minor Construction and Recapitalization.......................................6-26

6.4.1 Infrastructure Recapitalization Program .................................................................6-27

6.4.2 Defense Nuclear Security Minor Construction Investment.....................................6-29

6.4.3 Site-Directed Minor Construction Investments.......................................................6-29

6.5 Sustainment...........................................................................................................................6-30

6.5.1 Infrastructure Operations and Sustainment ...........................................................6-30

6.5.2 Programmatic Facility Sustainment.........................................................................6-32

6.5.3 Site-Directed Sustainment Investments..................................................................6-33

6.6 Disposition of Excess Facilities...............................................................................................6-33

6.7 Modernization of Programmatic Equipment.........................................................................6-34

6.7.1 Programmatic Equipment Investments...................................................................6-34

6.7.2 Site-Directed Equipment Investments ....................................................................6-35

6.8 Leveraging Weapons Activities Investments Across DOE/NNSA ...........................................6-35

6.8.1 Support of Nonproliferation Efforts........................................................................6-35

6.8.2 Support of Counterterrorism and Counterproliferation and Emergency 

Operations Efforts ...................................................................................................6-39

Chapter 7 Workforce......................................................................................................................... 7-1

7.1 Workforce Composition...........................................................................................................7-2

7.1.1 Federal Workforce.....................................................................................................7-2

7.1.2 Management and Operating Workforce ...................................................................7-3

7.1.3 Non-Management and Operating Workforce ...........................................................7-4

7.2 Status .......................................................................................................................................7-5

7.2.1 Workforce Demographics..........................................................................................7-7

7.3 Managing the Workforce Career Cycle..................................................................................7-11

7.3.1 Early Engagement....................................................................................................7-12

7.3.2 Recruitment and Hiring ...........................................................................................7-14

7.3.3 Developing and Training..........................................................................................7-15

7.3.4 Retaining and Sustaining .........................................................................................7-18

7.4 Challenges and Strategies......................................................................................................7-18

7.5 Workforce Accomplishments.................................................................................................7-20

Chapter 8 Budget and Fiscal Estimates.............................................................................................. 8-1

8.1 Planning, Programming, Budgeting, and Evaluation ...............................................................8-1

8.2 Portfolio Management.............................................................................................................8-2

8.3 Fiscal Year 2024 Future Years Nuclear Security Program........................................................8-3

8.4 Stockpile Management............................................................................................................8-3

8.4.1 Budget........................................................................................................................8-3

8.4.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted 

Budget........................................................................................................................8-4

8.4.3 Key Milestones ..........................................................................................................8-6
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8.5 Production Modernization.......................................................................................................8-6

8.5.1 Budget........................................................................................................................8-6

8.5.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted 

Budget........................................................................................................................8-7

8.5.3 Key Milestones ..........................................................................................................8-9

8.6 Stockpile Research, Technology, and Engineering.................................................................8-13

8.6.1 Budget......................................................................................................................8-13

8.6.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted 

Budget......................................................................................................................8-14

8.6.3 Key Milestones ........................................................................................................8-15

8.7 Infrastructure and Operations...............................................................................................8-16

8.7.1 Budget......................................................................................................................8-16

8.7.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted 

Budget......................................................................................................................8-17

8.7.3 Key Milestones ........................................................................................................8-19

8.7.4 Infrastructure Maintenance and Recapitalization Investments..............................8-19

8.8 Other Weapons Activities......................................................................................................8-21

8.8.1 Budget......................................................................................................................8-21

8.8.2 Academic Programs and Community Support ........................................................8-21

8.8.3 Secure Transportation Asset ...................................................................................8-22

8.8.4 Defense Nuclear Security ........................................................................................8-22

8.8.5 Information Technology and Cybersecurity ............................................................8-24

8.8.6 Legacy Contractor Pensions and Settlement Payments..........................................8-24

8.9 Weapons Activities Cost Beyond the FYNSP Period ..............................................................8-24

8.9.1 Basis for Budget Projections....................................................................................8-25

8.9.2 Stockpile Major Modernization...............................................................................8-25

8.9.3 Construction ............................................................................................................8-35

8.10 Affordability ...........................................................................................................................8-36

Chapter 9 Conclusion ........................................................................................................................ 9-1

Appendix A Requirements Mapping..................................................................................................A-1

A.1 National Nuclear Security Administration Response to Statutory Reporting 

Requirements and Related Requests...................................................................................... A-1

A.2 50 U.S. Code § 2523 ................................................................................................................ A-1

A.3 50 U.S. Code § 2538a .............................................................................................................. A-8

A.4 H.R. 116-449............................................................................................................................ A-9

A.5 H.R. 244................................................................................................................................... A-9

A.6 Related Legislation: 50 U.S. Code § 2521............................................................................... A-9

A.7 Related Legislation: 50 U.S. Code § 2522............................................................................. A-11

A.8 Related Legislation: 50 U.S. Code § 2524............................................................................. A-11

A.9 Related Legislation: 50 U.S. Code § 2538b........................................................................... A-12

A.10 Related Legislation: S. 4049 NDAA for Fiscal Year 2021 ...................................................... A-12

A.11 Related Legislation: S. 1605A NDAA for Fiscal Year 2022 .................................................... A-13

Appendix B Weapons Activities Capabilities......................................................................................B-1

B.1 Weapon Science and Engineering............................................................................................B-1

B.2 Weapon Simulation and Computing........................................................................................B-3
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B.3 Weapon Design and Integration ..............................................................................................B-3

B.4 Weapon Material Processing and Manufacturing ...................................................................B-4

B.5 Weapon Component Production .............................................................................................B-5

B.6 Weapon Assembly, Storage, Testing, and Disposition.............................................................B-6

B.7 Transportation and Security ....................................................................................................B-7

Appendix C Exascale .........................................................................................................................C-1

C.1 Challenges................................................................................................................................C-2

C.2 Approaches and Strategies ......................................................................................................C-2

C.3 Collaborative Management .....................................................................................................C-3

C.4 Milestones................................................................................................................................C-4

C.5 Conclusion................................................................................................................................C-4

Appendix D Stockpile Responsiveness Program.................................................................................D-1

Appendix E Industrial Base................................................................................................................ E-1

E.1 Framework ...............................................................................................................................E-1

E.2 Risk Management ....................................................................................................................E-2

E.2.1 Monitoring.................................................................................................................E-2

E.2.2 Mitigation ..................................................................................................................E-3

E.3 Interagency Coordination ........................................................................................................E-3

Appendix F Workforce and Site-Specific Information ........................................................................ F-1

F.1 National Nuclear Security Administration ...............................................................................F-2

F.1.1 Federal Workforce.....................................................................................................F-2

F.2 National Security Laboratories.................................................................................................F-6

F.2.1 Lawrence Livermore National Laboratory.................................................................F-6

F.2.2 Los Alamos National Laboratory..............................................................................F-15

F.2.3 Sandia National Laboratories ..................................................................................F-26

F.3 Nuclear Weapons Production Facilities.................................................................................F-38

F.3.1 Kansas City National Security Campus ....................................................................F-38

F.3.2 Pantex Plant.............................................................................................................F-47

F.3.3 Savannah River Site .................................................................................................F-54

F.3.4 Y-12 National Security Complex .............................................................................F-61

F.4 The National Security Site......................................................................................................F-69

F.4.1 Nevada National Security Site .................................................................................F-69

Appendix G Glossary ........................................................................................................................G-1

Appendix H Acronyms and Abbreviations .........................................................................................H-1

Appendix I List of Figures and Tables..................................................................................................I-1
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Legislative Language

Title 50 of United States Code Section 2523 (50 U.S. Code § 2523), requires that:

The Administrator, in consultation with the Secretary of Defense and other appropriate officials 

of the departments and agencies of the Federal Government, shall develop and annually update 

a plan for sustaining the nuclear weapons stockpile. The plan shall cover, at a minimum, stockpile 

stewardship, stockpile management, stockpile responsiveness, stockpile surveillance, program 

direction, infrastructure modernization, human capital, and nuclear test readiness. The plan shall 

be consistent with the programmatic and technical requirements of the most recent annual 

Nuclear Weapons Stockpile Memorandum. 

Pursuant to previous statutory requirements, the Department of Energy’s National Nuclear Security 

Administration (DOE/NNSA) has submitted reports on the plan to Congress annually since 1998, with the 

exception of 2012.

1

 

The Fiscal Year 2024 Stockpile Stewardship and Management Plan (SSMP) is a detailed report of 

DOE/NNSA’s 25-year program of record to maintain the safety, security, and effectiveness of the nuclear 

stockpile and is primarily captured in this single, unclassified document. A classified annex to the SSMP

contains supporting details concerning the U.S. nuclear stockpile and stockpile management.

1

In 2012, a Fiscal Year 2013 Stockpile Stewardship and Management Plan was not submitted to Congress because analytical work 

conducted by the Department of Defense and NNSA to evaluate the out-year needs for nuclear modernization activities across 

the nuclear security enterprise had not yet been finalized. 
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Chapter 1

Overview and Strategic Context for 

Managing the Nuclear Weapons Stockpile

The international security environment has deteriorated in recent years, in large part due to the actions 

of the United States’ strategic competitors and their heavy investment in new nuclear capabilities. The 

People’s Republic of China has embarked on an ambitious expansion, modernization, and diversification 

of its nuclear forces and has established a nascent nuclear triad. The Russian Federation continues to 

emphasize nuclear weapons in its strategy, modernize and expand its nuclear forces, and brandish nuclear 

weapons in support of its revisionist security policy. As a result, by the 2030s the United States will, for 

the first time in its history, face two major nuclear powers as strategic competitors and potential 

adversaries. For the foreseeable future, nuclear weapons will continue to provide unique deterrence 

effects that no other element of U.S. power can provide, given the reality of today’s evolving and uncertain 

international security environment. 

Ensuring the U.S.strategic deterrent remains safe, secure, and effective without nuclear explosive testing, 

and that the United States’ deterrence commitments to its allies remain strong and credible requires 

significant and coordinated effort. Responsibility for this mission is shared by the Department of Defense 

(DoD) and the Department of Energy’s National Nuclear Security Administration (DOE/NNSA). Only 

through the two Departments aligning their priorities, programs, and funding can U.S. nuclear forces meet 

deterrence and assurance requirements. 

DOE/NNSA partners with DoD through the Nuclear Weapons Council on the joint nuclear weapons

lifecycle processto execute the Nation’s nuclear weapons programs. DoD and DOE/NNSA use this process 

to manage weapons sustainment and modernization needs, from concept assessment to full-scale 

production, and finally, to retirement and dismantlement. DoD and DOE/NNSA continue to make progress

across the current major warhead programs as DOE/NNSA performs an unprecedented level of 

component development, qualification, system integration, and production activities. In December 2022, 

DOE/NNSA achieved a major scientific breakthrough decades in the making by reaching fusion ignition at

Lawrence Livermore National Laboratory (LLNL). LLNL’s National Ignition Facility conducted the first 

controlled fusion experiment in history to reach this milestone, also known as scientific energy breakeven, 

meaning it produced more energy from fusion than the laser energy used to drive it. This first-of-its-kind 

feat will provide unprecedented capability to support DOE/NNSA’s Stockpile Stewardship Program and 

has implications for the future of clean power.

The weapons comprising the U.S. nuclear stockpile are currently assessed to be safe, secure, and effective. 

However, continued science and infrastructure investments are needed to ensure the stockpile can 

provide a timely response to threat developments, technology opportunities, and maintain effectiveness 

over time. Recapitalizing the nuclear security enterprise, including the workforce, infrastructure, 

production capacity and capability, and the scientific base that supports it, is key to ensuring these goals 

can be achieved. Therefore, DOE/NNSA is currently undertaking a risk-informed, complex, and 

time-constrained modernization and recapitalization effort to support continued mission success, 

responsive to the priorities identified in the 2022 Nuclear Posture Review. 
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DOE/NNSA draws authority for managing the Nation’s nuclear stockpile from the Atomic Energy Act of 

1954 (42 U.S. Code § 2011 et seq.) and, more specifically, the National Nuclear Security Administration

Act (50 U.S. Code § 2401 et seq.) (NNSA Act). DOE/NNSA’s broad set of enduring missions are to protect 

the Nation by maintaining a safe, secure, and effective nuclear weapons stockpile, reduce global nuclear

threats, and provide the Navy’s submarines and aircraft carriers with militarily effective nuclear 

propulsion. Activities related to DOE/NNSA’s stockpile mission conduct are referred to in this document 

as Weapons Activities.

DOE/NNSA’s annual Stockpile Stewardship and Management Plan (SSMP) has two primary purposes:

◼ Document DOE/NNSA’s plans to:

– Maintain the current stockpile

– Modernize the stockpile as needed to respond to evolving deterrent needs

– Advance the science that enablesstockpile stewardship to enhance the potential performance 

and understanding of the stockpile’s aged, modified, and modernized nuclear weapons

– Maintain and modernize supporting infrastructure

– Sustain DOE/NNSA’s highly skilled workforce

◼ Provide DOE/NNSA’s formal response to multiple statutory and administrative reporting 

requirements, which can be found in Appendix A, “Requirements Mapping,” including:

– Annual life extension program reporting required under the Explanatory Statement 

accompanying the Consolidated Appropriations Act, 2017 (P.L. 115-31)

– Actual or potential risks to, or specific gaps in, any element of the industrial base that supports 

nuclear weapons components’ subsystems or materials, in addition to any mitigation actions 

needed as requested through Section 3135 of the National Defense Authorization Act for Fiscal 

Year 2022 (P.L. 117-81) 

This fiscal year (FY) 2024 SSMP serves as the annual plan for sustaining the nuclear weapons stockpile 

required by statute. The 25-year strategic plan was developed in alignment with strategic guidance, 

including the 2022 Nuclear Posture Review, the Nuclear Weapons Council’s Strategic Plan for Fiscal Years 

(FY) 2019 – 2044, the FY 2020 – 2025 Nuclear Weapons Stockpile Plan, and other policy directives (see 

Section 1.2).

1.1 Policy Framework Summary

The NNSA Act directs DOE/NNSA “to maintain and enhance the safety, reliability, and performance of the 

U.S. nuclear weapons stockpile, including the ability to design, produce, and test, to meet national security 

requirements.” 

Recently, the 2022 National Defense Strategy and the accompanying Nuclear Posture Review stated that 

as long as nuclear weapons exist, the fundamental role of U.S. nuclear weapons is to deter nuclear attack 

on the United States and its allies and partners. The 2022 Nuclear Posture Review also reinforced that the 

United States will maintain nuclear forces that are responsive to the threats it faces and affirmed the 

following roles for nuclear weapons:

◼ Deter strategic attacks

◼ Assure allies and partners

◼ Achieve U.S. objectives, if deterrence fails
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Furthermore, the 2022 Nuclear Posture Review represented a comprehensive, balanced approach to U.S. 

nuclear strategy, policy, posture, and forces, and reaffirmed that maintaining a safe, secure, and effective 

nuclear deterrent and strong and credible extended deterrence commitments remains a top priority for 

DoD, DOE/NNSA, and the Nation. 

The 2022 Nuclear Posture Review also identified three pillars for nuclear deterrent mission success:

◼ DoD and NNSA will develop and implement a Nuclear Deterrent Risk Management Strategy to 

identify, prioritize, and recommend actions across the portfolio of nuclear programs and monitor 

the overall health of the nuclear deterrent as the United States sustains current capabilities and 

transitions to modernized systems.

◼ NNSA will institute a Production-based Resilience Program to complement the science-based 

stewardship program and ensure the nuclear security enterprise is capable of full-scope 

production for new or emerging requirements. 

◼ NNSA will establish a Science and Technology Innovation Initiative to accelerate integrating 

science and technology throughout mission requirements and help provide an increased focus on 

leveraging science and technology to support the weapon design and production phases of 

weapon development. 

DOE/NNSA, in partnership with DoD, continues to implement the direction from the 2022 Nuclear Posture 

Review.

1.2 The DOE/NNSA Nuclear Security Enterprise

The DOE/NNSA nuclear security enterprise (Figure 1–1) consists of DOE/NNSA Headquarters (located in 

Washington, DC; Germantown, Maryland; and Albuquerque, New Mexico); the DOE/NNSA field offices;

the three national security laboratories (two of which have production missions); the four nuclear 

weapons production sites; and the Nevada National Security Site (NNSS). DOE/NNSA implements the 

overall nuclear weapons strategy, in collaboration with its management and operating (M&O) partners, 

and oversees and coordinates activities to accomplish them in an efficient, fiscally responsible manner.

1.2.1 National Security Laboratories

Three national security laboratories are devoted to nuclear weapons design and data interpretation:

◼ LLNL in Livermore, California

◼ Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico

◼ Sandia National Laboratories (SNL) in Albuquerque, New Mexico, and Livermore, California

The primary mission of these nationalsecurity laboratories is to perform research to develop, sustain, and 

implement nuclear weapons design, simulation, modeling, and experimental capabilities and 

competencies. This research ensures confidence in the current and future stockpile without requiring 

nuclear explosive testing. All three laboratories are Federally Funded Research and Development Centers 

(FFRDCs).1 They engage in long-term research, development, test, and evaluation activities for the nuclear 

1 FFRDCs are unique nonprofit entities sponsored and funded by the U.S. Government to meet special long-term research or 

development needs that cannot be met as effectively by existing in-house or contractor resources. FFRDCs are operated, 

managed, and/or administered by either a university or consortium of universities, another not-for-profit or nonprofit 

organization, or an industrial firm either as an autonomous organization or an identifiable separate operating unit of a parent 

organization.
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weapons missions and apply science, technology, and engineering to solve many other national security 

challenges. Along with the national security laboratories, other DOE national laboratories also support 

the Weapons Activities and Defense Nuclear Nonproliferation programs.

Figure 1–1. The DOE/NNSA nuclear security enterprise

1.2.2 Nuclear Weapons Production Facilities

The four nuclear weapons production sites conduct a range of stockpile management activities:2

◼ The Kansas City National Security Campus in Kansas City, Missouri, produces non-nuclear 

components.

◼ The Pantex Plant in Amarillo, Texas, manufactures and tests high explosive components and 

assembles, disassembles, and refurbishes stockpile weapons and components.

◼ The Y-12 National Security Complex in Oak Ridge, Tennessee, manufactures uranium, along with

other nuclear weapon components, and dismantles and stores highly enriched uranium.

◼ The Savannah River Site in Aiken, South Carolina, extracts, recycles, and loads tritium into gas 

transfer systems.

3

In addition, the nuclear production facilities provide or contribute to critical stockpile capabilities, 

including science, production, materials, and processes that are necessary for sustaining the stockpile.

2 Some critical production capabilities also exist at LANL and SNL. 

3 DOE’s Savannah River National Laboratory at Savannah River Site also conducts research and development in support of tritium 

processing and gas transfer system design and certification activities.
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1.2.3 Nevada National Security Site

NNSS near Las Vegas, Nevada, works with the national security laboratories to provide facilities, 

infrastructure, and personnel to conduct unique nuclear and non-nuclear experiments that are essential to 

maintaining the stockpile. It is the primary location where experiments with radioactive and other 

high-hazard materials are conducted and the only location where high explosive-driven plutonium 

experiments can be conducted at weapon-scale with weapon-relevant amounts of special nuclear material. 

In accordance with the U.S. moratorium on nuclear explosive testing, such experiments and activities are 

always subcritical. NNSS also develops and deploys state-of-the-art diagnostics and instrumentation, 

analyzes data, stores programmatic materials, conducts criticality experiments, and supports other 

DOE/NNSA activities.

1.3 Introduction to the Nuclear Weapons Stockpile

The nuclear stockpile’s size and composition continues to change in response to U.S. national security 

requirements, though the average warhead age in the stockpile remains high. Many weapons systems 

are past their design life expectancy and require stockpile management activities to assess their condition 

and perform maintenance as well as enhanced surveillance to confirm weapons are operable and extend 

weapon lifetimes. With several major warhead modernization activities underway, DOE/NNSA is working 

toward reducing average warhead age while meeting emerging challenges on a timeline that does not put 

the nuclear deterrent at risk. 

The current stockpile consists of active weapons, which are maintained to meet military requirements, 

and inactive weapons, which are used to augment or replace warheads in the active stockpile as 

necessary. Retired weapons are not included in the count of stockpile weapons. Table 1–1 reflects the 

major characteristics of the Nation’s current stockpile, which is composed of two types of 

submarine-launched ballistic missile warheads, two types of intercontinental ballistic missile warheads, 

several types of gravity bombs, and a cruise missile warhead.

The classified Annex to this plan includes specific technical details about the stockpile by warhead type.

Table 1–1. Current U.S. nuclear weapons and associated delivery systems

Warheads—Strategic Ballistic Missile Platforms

Type

a

Description Delivery System Laboratories Mission Service

W78 Reentry vehicle warhead Minuteman III intercontinental 

ballistic missile

LANL/SNL Surface to 

surface

Air Force

W87-0 Reentry vehicle warhead Minuteman III intercontinental 

ballistic missile

LLNL/SNL Surface to 

surface

Air Force

W76‐0/1/2 Reentry body warhead Trident II D5 submarine‐

launched ballistic missile

LANL/SNL Underwaterto 

surface

Navy

W88 Reentry body warhead Trident II D5 submarine‐

launched ballistic missile

LANL/SNL Underwaterto 

surface

Navy

Bombs—AircraftPlatforms

B61‐3/4 Nonstrategic bomb F‐15, F‐16, certified

NATO aircraft

LANL/SNL Air to surface Air Force/Select 

NATO forces

B61‐7 Strategic bomb B‐2 bomber LANL/SNL Air to surface Air Force

B61‐11 Strategic bomb B‐2 bomber LANL/SNL Air to surface Air Force

B61-12 Strategic bomb B‐2 bomber LANL/SNL Air to surface Air Force

B83‐1 b Strategic bomb B‐2 bomber LLNL/SNL Air to surface Air Force
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Warheads—Cruise Missile Platforms

W80‐1 Air‐launched cruise 

missile strategic weapons

B‐52 bomber LLNL/SNL Air to surface Air Force

LANL = Los Alamos National Laboratory NATO = North Atlantic Treaty Organization

LLNL = Lawrence Livermore National Laboratory SNL = Sandia National Laboratories

a The suffix associated with each warhead or bomb type (e.g., “-0/1/2” for the W76) represents the modification associated 

with the respective weapon.

b The 2022 Nuclear Posture Review directed the retirement of the B83-1. Specific details of the B83-1 retirement and 

dismantlement plan remain classified.

1.4 Overall Strategy, Objectives, and Prioritization of Weapons 

Activities

DOE/NNSA continues to execute its long-standing nuclear 

warhead modernization efforts in conjunction with the 

modernization of DoD delivery platforms, along with the 

necessary modernization of its capabilities and infrastructure. 

This approach will allow the necessary flexibility for future policy 

decisions related to nuclear modernization as the United States 

adjusts to the changing international threats facing the country

and its allies and partners. The nuclear weapons stockpile is 

currently safe, secure, and militarily effective. However, the 

United States must continue to invest in the weapons and 

infrastructure modernization programs to provide the 

capabilities needed to ensure the deterrent’s viability in the 

future. DOE/NNSA’s mission is to enhance science, technology, 

and engineering capabilities to address emerging challenges,

improve production processes’ efficiency and effectiveness, and to provide a credible deterrent despite

unanticipated risks or technological surprise. Due to the long lead times necessary to prepare and 

establish nuclear capabilities, the United States will not have the weapons and infrastructure in place to 

support the nuclear stockpile unless DOE/NNSA takes action to reestablish and recapitalize these 

capabilities now. 

The FY 2024 budget for Weapons Activities includes funding for several nuclear modernization programs 

and was developed in support of the Administration’s 2022 Nuclear Posture Review:

◼ Define the Capability to Effectively Engage and Defeat Hardened and Deeply Buried Targets. 

The Nuclear Weapons Council established a joint NNSA/DoD Hard and Deeply Buried Target 

Defeat Team, coordinated through the Assistant Secretary of Defense for Nuclear Chemical and 

Biological Defense Programs/Office of Nuclear Matters, to determine future options for defeating 

such targets.

◼ Advance the W87-1 Modification Program. The W87-1 Modification Program will replace the 

aging W78 warhead using a modified existing legacy W87-0 design and will deploy new 

technologies that improve safety and security, address material obsolescence, and improve 

warhead manufacturability. In FY 2022, DOE/NNSA matured select technologies and furthered 

system test and qualification planning. In FY 2023, the Nuclear Weapons Council authorized entry 

into Phase 6.3, Development Engineering.

◼ Develop the W93. The W93 Modernization Program was established to support the Navy’s 

identified need for a new reentry body. Anchored on previously tested nuclear components, the 

Major Goals of Weapons Activities

• Ensure the nuclear weapons stockpile 

continues to meet DoD deterrent 

requirements while enhancing warhead 

safety and security

• Modernize production capabilities and 

nuclear security enterprise facilities

• Provide experimental and computational 

capabilities to support the stockpile

annual assessment and certification

• Recruit, train, and retain a highly skilled 

and diverse workforce to meet mission 

deliverables
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W93 will incorporate modern technologies to improve safety, security, and flexibility to address 

future threats. It will be designed for ease of manufacturing, maintenance, and certification. Key 

nuclear components will be based on currently deployed and previously tested nuclear designs, 

and extensive stockpile component and materials experience. It will also support the continued 

viability of DoD’s operational flexibility and effectiveness as the United States transitions from 

Ohio-class submarines to a smaller fleet of Columbia-class submarines. The W93 will not require 

additional nuclear explosive testing to be certified.

Carrying out the W93 program is vital for continuing the United States’ longstanding cooperation 

with the United Kingdom, which is also modernizing its nuclear forces. As an allied but 

independent nuclear power that contributes to the North Atlantic Treaty Organization’s nuclear 

deterrent posture, the United Kingdom’s nuclear deterrent is critical to U.S. national security. 

In summary, the United States must continue its ability to maintain and certify a safe, secure, and 

effective nuclear arsenal. Synchronized with DoD delivery platform replacement programs, DOE/NNSA 

will sustain and deliver the warheads necessary to support the Nation’s strategic and non-strategic 

nuclear capabilities on time by:

◼ Completing the B61-12 Life Extension Program

◼ Completing the W88 Alteration 370

◼ Maintaining synchronization of DOE/NNSA’s W80-4 warhead with DoD’s Long Range Standoff 

cruise missile program 

◼ Exploring future warhead options to meet the required military characteristics based on the 

threats and vulnerabilities potential adversaries pose, including possible common reentry systems 

for Air Force and Navy systems

◼ Delivering the W87-1 and W93 warheads to support the land- and sea-based legs of the triad

DOE/NNSA uses several major strategies to sustain and maintain the stockpile and support DOE/NNSA 

mission priorities, including:

◼ Assessing the stockpile annually through science-based stockpile stewardship:

– Assessing whether the current and future nuclear stockpile’s safety, reliability, and 

performance can be assured in the absence of underground nuclear explosive testing

– Renewing, developing, and enhancing science capabilities to assess effects of aging, 

remanufacture and material options, and evolving threat environments on warhead 

performance

– Maintaining the readiness to conduct an underground nuclear explosive test, if required, to 

assess safety and performance characteristics of the Nation’s stockpile, or if otherwise 

directed by the President

◼ Extending the nuclear deterrent’s life through modernizations:

– Replacing obsolete technology

– Enhancing stockpile safety and security

– Meeting military requirements

◼ Assuring the capabilities to support the nuclear deterrent in the near and long-term (these 

capabilities are discussed in the FY 2023 SSMP in Chapter 3, “Weapons Activities Capabilities that 

Support the Nuclear Security Enterprise”):
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– Developing modern materials and design and manufacturing options to enable a more modern 

and efficient production complex

– Renewing and sustaining critical production, manufacturing, and research capabilities

– Assuring a stable, reliable, and trusted domestic supply chain for nuclear weapon materials, 

components, and subsystems

◼ Advancing innovative experimental platforms, diagnostic equipment, and computational 

capabilities:

– Keeping technical expertise and capabilities on the cutting edge to support a responsive and 

resilient enterprise

◼ Providing safe and secure transport of nuclear weapons, weapon components, and special nuclear 

materials to meet mission requirements

◼ Implementing enterprise-wide recruitment and retention strategies which incorporate hiring, 

compensation and benefits flexibilities, and promoting a healthy work-life balance

◼ Enhancing cyber infrastructure and resiliency across the enterprise

The Integrated Stockpile Model in Figure 1–2 shows how the stockpile cycle’s main activities—plan, 

modernize, maintain, assess, and certify—link these strategies to sustain the stockpile and support 

mission priorities.

Figure 1–2. Integrated stockpile model
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1.5 Partnership with the Department of Defense

DOE/NNSA and DoD work collaboratively to maintain and modernize the stockpile and delivery systems. 

DOE/NNSA’s role is to ensure nuclear weapons remain safe, secure, and reliable, while DoD’s role is to 

provide a range of delivery options that can be tailored to meet the desired objectives. These 

complementary efforts are coordinated through the Nuclear Weapons Council. This council is a joint DoD 

and DOE/NNSA coordinating body established by Congress to facilitate aligning requirements and 

determine priorities as the two departments fulfill their shared responsibility to provide the Nation’s 

nuclear deterrent. 

The Nuclear Weapons Council regularly convenes to synchronize efforts between DoD and DOE/NNSA on 

the vision, strategy, and execution of the nuclear program aligned with the National Defense Strategy. 

The Nuclear Weapons Council also reviews costs and schedules for options related to the nuclear 

stockpile, driving DOE/NNSA and the Military Services to meet requirements in ways that are both costeffective and timely. The Nuclear Weapons Council fully supports DOE/NNSA’s efforts to establish a 

responsive and resilient nuclear security enterprise to meet U.S. deterrence and assurance needs. 

1.6 Challenges in Executing the Stockpile Stewardship and 

Management Plan

For most of the post-Cold War period, the focus of our nuclear security enterprise has been to sustain 

existing nuclear weapons and improve the ability to assess their safety, security, reliability, and 

effectiveness without nuclear explosive testing. When aging issues were identified in the stockpile, 

weapons were partially refurbished without changing their military characteristics. Many elements of the 

weapons production infrastructure were only required on a limited basis or not needed for these 

refurbishment efforts, causing a capability loss. 

Today, much of the stockpile has aged without comprehensive refurbishment. At a time of rising nuclear 

risks, a partial refurbishment strategy is no longer adequate to meet mission needs. A safe, secure, and 

effective nuclear deterrent requires modern weapons and a modern infrastructure, enabled by a 

world-class workforce equipped with modern tools. 

DOE/NNSA will continue to carry out robust risk management strategies within the nuclear security 

enterprise so that the deterrent is capable even in the face of significant uncertainties and unanticipated 

challenges. This proactive activity requires developing and sustaining a set of initiatives and actions that,

over time, will build resilience in the stockpile, production capabilities, and science and technology 

capabilities.

DoD also continues to make progress on the first recapitalization of the triad4since the end of the Cold 

War, and this effort cannot be accomplished alone. Consistent, on-going schedule integration between 

the warhead and delivery programs managed by DOE/NNSA and DoD, respectively, is key to delivering

timely and cost-effective capabilities that meet the Nation’s defense needs. The partnership between 

DoD and DOE/NNSA continues to be managed through the Nuclear Weapons Council, which has made 

tremendous progress to align priorities, schedules, and investments between the Departments to ensure 

the nuclear deterrent’s future viability.

4 A combination of platforms and weapons, the three legs of the U.S. nuclear triad (land, sea, and air), serve as the backbone of 

America’s national security (https://www.defense.gov/Experience/Americas-Nuclear-Triad/).
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DOE/NNSA has resourced plans to renew the essential manufacturing capabilities prioritized to meet DoD 

near-term to intermediate-term warhead deliveries and maintain workforce safety. DOE/NNSA’s plans

focus on five areas:

◼ Establishing a pit production capability

◼ Reestablishing high explosives synthesis, formulation, and production capabilities

◼ Modernizing and enhancing the facilities and capabilities needed to meet near-term to long-term 

needs for tritium

◼ Modernizing the production capabilities for secondary assemblies, radiation cases, and replacing

the current lithium production facility

◼ Modernizing and enhancing non-nuclear component research, development, testing, and 

production capabilities

Figure 1–3 shows the timeline necessary to meet warhead needs. 

Figure 1–3. Timeline for key infrastructure and capability investments for future warheads
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To support the above focus areas, other key considerations include:

◼ The nuclear weapons stockpile needs updated technologies that require investment in new 

processes, technologies, and tools for warhead design, qualification, certification, and production

in accordance with stringent and evolving stockpile specifications and requirements. The 

increased number of concurrent weapon system builds entail three requirements:

– Maturing new options with shortened development cycles

– Advancing the ability to predict weapon performance in configurations that were not tested 

underground

– Evaluating the impact of new materials and processes, reusing aging components in future 

systems, and enhancing production throughput

◼ Pursuing only the priority activities previously described does not exercise all phases and aspects 

of the joint nuclear weapons lifecycle. DOE/NNSA must devote some effort to less time-sensitive 

activities to transfer knowledge and skills to the newer generation of nuclear weapon designers 

and engineers, accelerate and enhance the weapon lifecycle, and strengthen integration between 

DoD and DOE/NNSA to sustain all required capabilities. This continued focus is reflected in the 

inclusion of Appendix D, which resubmits information on the programs, projects, and activities of 

the Stockpile Responsiveness Program. 

◼ DOE/NNSA must sustain the nuclear weapons supply chain availability and trustworthiness to 

assure industrial base viability and guard against potential counterfeit and sabotage. DOE/NNSA 

has implemented several initiatives through the Nuclear Enterprise Assurance Program to protect 

the supply chain. For example, DOE/NNSA’s nuclear security enterprise provides the tools and 

capabilities needed for trusted radiation-hardened silicon microelectronics. DOE/NNSA is 

installing new tooling and planning recapitalization efforts to extend the life of key and critical 

facilities to support continued capability. DOE/NNSA is also collaborating with partners to 

establish research and development efforts that could serve as future production capabilities. 
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Chapter 2

Stockpile Management

This chapter summarizes the activities the Department of 

Energy’s National Nuclear Security Administration 

(DOE/NNSA) manages to maintain the Nation’s nuclear 

weapons stockpile. These activities include sustaining, 

modernizing, and dismantling nuclear weapons; 

maintaining and modernizing production operations; and 

optimizing the scientific capabilities that underpin these 

efforts. 

Figure 2–1 provides an overview schematic of the Stockpile 

Management major subprograms:

◼ Stockpile Sustainment performs single-system and 

multi-system sustainment activitiesfor all warheads

in the current stockpile to include limited life 

component (LLC) exchanges, surveillance activities, 

significant finding investigations (SFI), weapons 

reliability reporting, annual assessments that 

provide a comprehensive understanding of the 

stockpile’s health, and warhead qualification and 

delivery system integration activities.

◼ Stockpile Major Modernization includes life extension programs (LEPs) to extend the lives of 

current stockpile weapons, modification programs (Mods) to change the operational capabilities

of stockpile systems, major alterations (Alts), which alter stockpile systems without changing their

operation capabilities, and warhead acquisition programs which provide modernized warhead 

capabilities designed to meet military requirements that cannot be met with other stockpile 

systems.

◼ Weapons Dismantlement and Disposition (WDD) manages dismantlement of retired weapons as 

well as disposition of weapon components, which can generate components and materials for 

Weapons Activities, including modernization programs, and other DOE/NNSA mission areas.

◼ Production Operations provides the base capabilities to enable weapon operations (i.e., 

assembly, disassembly, and production) planned for the warhead modernization, sustainment, 

and the WDD programs. Production Operations are not specific to one material stream. It 

coordinates closely with the Production Modernization program (see Chapter 3), which focuses 

on the special nuclear materials (such as plutonium and uranium) and components, as well as 

non-nuclear component modernization.

◼ Nuclear Enterprise Assurance (NEA) ensures the nuclear security enterprise actively manages 

subversion risks to the nuclear weapons stockpile and associated design, production, and testing 

capabilities.

Stockpile Management Accomplishments

• Completed Annual Assessment Cycle 27

• Achieved First Production Unit on the B61-12 

weapon and Joint Test Assembly (JTA)

• The Nuclear Weapons Council formally 

accepted the W88 Alt 370 and B61-12 into the 

stockpile and authorized entrance to Phase 6.6 

in fiscal year (FY) 2022 

• W80-4 received authorization to enter Phase 6.4

• Achieved last production unit delivery for W76-1 

MC4700 arming, fuzing, and firing system

• Achieved first production unit for MC4972-1 

Common High Efficiency Adaptable Telemetry 

Transmitter 1 month early, which is a multiprogram JTA transmitter

• W87-1 received authorization to enter Phase 6.3

• W93 received authorization to enter Phase 2
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Figure 2–1. Stockpile Management major subprograms

The remainder of Chapter 2 is organized around these five major subprograms.

Managing the stockpile requires comprehensive planning for all stockpile elements to integrate these 

activities with each other and with production capabilities. However, these activities alone cannot sustain 

the nuclear deterrent. Managing the stockpile also depends on a strong set of enabling capabilities 

covering the necessary science, technology, design, production, materials, and processes, as well as a 

workforce with the requisite skill set to execute these activities. These individual capabilities and the 

linkages to stockpile management are described at length in Chapters 3 and 4. Chapters 6 and 7 of this 

report address two specific elements of these capabilities—infrastructure and workforce—across all 

capabilities at an enterprise level, further reinforcing the need to sustain the health of capabilities to 

support the stockpile mission work.

2.1 Stockpile Sustainment

Stockpile sustainment activities are responsible for the ongoing health of the stockpile, including

surveillance; annual assessments; investigations; and ongoing maintenance such as LLC exchanges, code 

management, and surety operations to ensure weapons remain safe, secure, and effective over their 

lifecycles. Some weapons that remain in the stockpile are eventually updated or replaced through 

modernization programs to address aging issues, modified military requirements, and any anomalies, and 

to meet updated safety and security standards. These modernization activities (LEPs, Mods, Alts, and 

warhead acquisition programs) are addressed through the Stockpile Major Modernization activities 

discussed in Section 2.2.
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2.1.1 Assessing the Stockpile

The status of the stockpile is evaluated through continual, multilayered assessments of the safety, security, and military 

effectiveness of each U.S. nuclear weapon system. The annual 

stockpile assessment process evaluates the state of the stockpile 

by conducting physics and engineering analyses, experiments 

(such as hydrodynamic and subcritical experiments), and 

computer simulation/modeling. Assessments also evaluate the 

effects of aging on performance and quantify performance 

thresholds, uncertainties, and margins. Assessors gather a body 

of evidence to evaluate performance at the part, component, 

subsystem, and system levels to determine whether performance 

requirements are met. The processes combine data, analysis, and 

expert judgment with simulations and continually advancing 

capabilities to develop a final evaluation of the stockpile.

2.1.1.1 Annual Assessment

The Annual Stockpile Assessment Reporting Process is codified in 50 U.S. Code § 2525—Annual 

assessments and reports to the President and Congress regarding the condition of the United States 

nuclear weapons stockpile. The code requires the directors of the three national security laboratories to 

conduct independent annual assessment reviews on the state of all stockpile systems for which they are 

responsible. It also requires the Commander of the U.S. Strategic Command (USSTRATCOM) to assess the 

stockpile each year based in part on inputs from the national security laboratories. This process is not a 

recertification of the weapons in the stockpile; it is an assessment of each system’s existing certification 

basis. Each annual assessment builds on previous years’ experience with each weapon system and 

incorporates new information, and state-of-the-art capabilities, from stockpile maintenance, surveillance, 

experiments, simulations, and other sources to update the technical basis of each weapon system.

The assessments and conclusions in the Annual Assessment Reports are subject to inter-laboratory peer 

review by subject matter experts appointed by each laboratory’s director, program managers, and senior 

laboratory management. This effort culminates in a written summary and conclusion of the assessments 

from each laboratory director and the USSTRATCOM Commander. These findings are included as 

unabridged attachments to the statutorily required Report on Stockpile Assessments, prepared by the 

Nuclear Weapons Council for formal endorsement by the Secretaries of Energy and Defense and 

submitted to the President annually.

2.1.1.2 Weapon Reliability

DOE/NNSA publishes an annual Weapons Reliability Report, which provides an updated summary of 

reliability and yield characteristics of all weapons in the stockpile. The report’s purpose is to communicate 

to stakeholders the assessed reliability, reliability risks, and effects of test limitations. This report is the 

principal DOE/NNSA report on weapon systems reliability that USSTRATCOM uses for strategic planning 

actions. The Annual Assessment Review process informs this report, which incorporates data from 

surveillance activities.

2.1.1.3 Advanced Certification and Qualification

Advanced Certification develops tools and methods to ensure the safety and reliability of the current 

stockpile and prospective systems for stockpile modernization without further underground nuclear 

explosive testing. This subprogram delivers assessment methods, diagnostic and experimental 

Stockpile Sustainment 

Accomplishments

• Los Alamos National Laboratory, 

Sandia National Laboratories, and 

Lawrence Livermore National 

Laboratory completed annual 

assessment reviews for the deployed 

systems under their purview 

• Completed planned LLC exchanges

• Delivered modernized components 

and technology to weapons 

modernization programs

• Surveilled the deployed stockpile
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techniques, data analysis methods, and assessments of the certifiability of design options for future 

stockpile needs. Advanced Certification activities preserve and reanalyze legacy nuclear test data and 

validate simulation codes and models against improved physics models, and hydrotest and subcritical 

experimental data. These activities enhance DOE/NNSA’s understanding of a weapon system’s 

performance, improve the quantification of margins and uncertainties, and improve the fidelity and agility 

of certification methods.

DOE/NNSA qualifies nuclear weapons components, subsystems, and integrated systems to the military 

characteristics and stockpile-to-target sequence environmental requirements, including normal, 

abnormal, and hostile environments prior to their introduction into the stockpile. Qualification plans for 

each stockpile system specify the experimental data, modeling, simulation capabilities, and production 

data required to ensure system safety, security, reliability, and performance. While qualification is carried 

out by each warhead program, Advanced Qualification activities improve qualification methods by 

anticipating needs and developing the tools, capabilities, and material fabrication options that will enable 

qualification of replacement or new materials/components with a focus on increased responsiveness and 

enhanced analysis. These activities address the qualification challenges for advanced manufacturing 

methods, replacement materials, and new systems architectures. Additionally, these activities are 

focused on methods to streamline qualification processes to reduce costs, timescales, resources, floor 

space and testers, and to standardize methods and requirements across warhead systems. Advanced 

Certification and Qualification activities promote the close coordination between design and production 

agencies to capture qualification challenges early in the development process and design for easier 

manufacturing and relaxed specifications, where possible, without compromising certification needs.

2.1.1.4 Quantification of Margins and Uncertainties

Assessing weapon performance requires integrating many sources of data and expertise. One way 

performance is gauged is through the quantification of margins and uncertainties methodology, which 

evaluates the degree to which a weapon operates within the bounds of specified operating characteristics 

or requirements. This methodology supports nuclear stockpile decision-making and enables 

risk-informed decisions. A key metric is the confidence factor, or the ratio of margin (M) to 

uncertainty (U), M/U. Margin is the difference between the expected value and the minimum value of a 

parameter to ensure some aspect of warhead performance is met. Uncertainty is the degree to which 

these values are known, including the variation that exists due to design tolerances and manufacturing 

processes. Stockpile Research, Technology, and Engineering activities (also referred to as Stockpile 

Stewardship activities) evaluate approaches to increase margin when possible and to quantify 

uncertainties. These tasks are achieved by performing experiments in areas such as material properties 

to provide data for improving the reliability of the models used to simulate warhead operation. In 

summary, quantification of M/U provides an understanding of the basis for the assessed confidence in 

the weapons system performance and adds further confidence to the conclusions of the assessment

process.

2.1.2 Stockpile Surveillance

Surveillance activities provide data to evaluate the safety, security, reliability, and performance of 

weapons in the current stockpile in support of annual assessments. The cumulative body of this data also 

supports future stockpile decisions based on the assessment activities described above. The surveillance 

program has six goals:

1. Identify manufacturing and design defects that could affect safety, security, reliability, or 

performance
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2. Assess risks to the safety, security, reliability, and performance of the stockpile

3. Determine the margins between design requirements and performance at the system, 

component, and material levels

4. Identify aging-related changes and trends at the subsystem, component, and material levels

5. Further develop capabilities for predictive assessments and provide lifetime estimates of stockpile 

components and materials

6. Provide critical data for the annual Weapons Reliability Report and the Report on Stockpile 

Assessments

DOE/NNSA conducts stockpile surveillance through weapon disassembly and inspection, stockpile flight

testing, stockpile laboratory testing, component testing, material evaluation, and test equipment. 

DOE/NNSA continually refines planning requirements for stockpile evaluation activities based on new 

surveillance information, new diagnostic tool deployment, annual assessment findings, and analysis of 

historical information using modern assessment methodologies and computational tools. 

2.1.2.1 Disassembly and Inspection

Weapons sampled from the production lines or returned from Department of Defense (DoD) custody are 

inspected during disassembly. Weapon disassembly is conducted in a controlled manner to identify any 

abnormal conditions and preserve the components for subsequent evaluations. These inspections may 

detect anomalies that provide important clues about the health of the weapons, while also advancing 

knowledge and understanding of the stockpile.

2.1.2.2 System, Flight, Laboratory, and Component Testing

A subset of weapons that have undergone disassembly and inspection (D&I) are reassembled into joint 

test assembly (JTA) configurations to represent the original build to the greatest extent possible. Select 

non-nuclear components from weapon systems are used directly in the JTA, while nuclear materials are 

replaced with surrogate materials and custom diagnostic equipment. JTAs may contain extensive 

telemetry instrumentation to provide detailed information on component and subsystem performance 

during flight environments. JTA units are delivered to and flown by the DoD operational command 

responsible for the system. For each weapon system, JTAs are flown on delivery platforms to gather the 

information required to assess the effectiveness and reliability of the weapon, the launch or delivery 

platform, and the associated crews and procedures. System-level flight tests are conducted jointly with 

the Air Force and Navy.

After D&I, certain components of selected weapons are reassembled into test bed configurations using 

parent unit parts. Stockpile laboratory tests conducted at the subsystem, or component level, assess 

major assemblies and components and, ultimately, the materials that comprise the components. This 

surveillance process enables detection and evaluation of the onset of aging, trends, and anomalous 

changes at the component or material level.

Components and materials from the D&I process undergo further evaluations to assess component

physical configuration, functionality, performance margins and trends, material behavior, and aging 

characteristics. The testing can involve nondestructive and destructive evaluation techniques and can be 

used to aid in developing predictive performance and aging models of components and materials.

2.1.2.3 Test Equipment

Custom sets of test equipment (i.e., testers) can be applied to systems, subsystems, major components, 

and processes. Testers perform two key functions. First, they provide the mechanical, electrical, and 
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radiofrequency stimuli to the system in a specified sequence to evaluate component functionality relative 

to requirements. Second, they simultaneously collect data on the components and subsystems

performance and for product acceptance. The data collected are used as input to assess the performance 

and assert the continued certification of the weapon system as safe, secure, reliable, and effective.

2.1.2.4 Anomaly Investigative Process

When anomalies that could adversely affect weapon safety, security, reliability, or performance are 

discovered in surveillance data or are identified and reported to DOE/NNSA by DoD, technical analyses 

are conducted to determine whether observations warrant an SFI. Investigations can include historical 

data modeling, focused materials experiments, research and studies, major system test replication, and 

subsystem and subcomponent tests. These SFIs can continue through several annual assessment cycles. 

SFIs are closed after the impacts to system performance, reliability, or safety have been assessed and 

follow-up actions are determined, if necessary. A tracking and reporting system monitors anomalies and 

SFIs as they progress from initial discovery, as well as the status of any corrective actions taken. This 

information is also reported in the annual assessment for the weapon system.

2.1.3 Maintaining the Stockpile

Maintaining the current stockpile involves many ongoing activities:

◼ Completing LLC exchanges of gas transfer systems (GTSs), power sources, and neutron generators, 

as required, to sustain system functionality

◼ Responding to emerging issues that do not rise to the level of a major Alt or LEP through 

maintenance, minor repairs and rebuilds, incorporation of surety features, and other changes

◼ Maintaining production authorization by conducting periodic nuclear explosives safety studies

◼ Maintaining specialized support equipment, such as custom tooling, for stockpile operations

◼ Provisioning for spare and replacement parts that are consumed in stockpile operations

2.1.3.1 Limited Life Components

Weapons contain LLCs that require periodic replacement to sustain system functionality and 

performance. Age-related changes affecting these components are predictable and well understood, and 

surveillance is conducted to ensure the components continue to meet performance requirements 

throughout their projected lifetime. Periodic LLC exchanges replace these components at defined 

intervals throughout a weapon’s lifetime. DOE/NNSA produces LLCs and collaborates with DoD to jointly 

manage component delivery and installation. These components include GTSs, power sources, and 

neutron generators. 

Gas Transfer Systems

GTSs are designed, produced, filled, and delivered to DoD for existing weapon systems. Compared to 

historical GTSs, modern GTS designs increase weapon performance margins, thereby improving 

maintenance efficiency and enhancing weapon safety and reliability. Function-testing life storage units 

and development hardware validates performance characteristics and provides research and 

development (R&D) to inform current and future GTS designs. New GTS designs are evaluated to verify 

the GTSs may be loaded in the production facilities and meet weapons systems performance 

characteristics. In parallel to these R&D efforts, production facilities are maintained for gas-loading 

operations, GTS surveillance, and tritium recovery from end-of-life GTSs. 
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Power Sources

Current and future planned nuclear weapons require specialized power sources that meet stringent 

reliability and performance requirements. Requirements for size, weight, active life, responsiveness, and 

output are unique to nuclear weapon applications, and are manufactured within the DOE/NNSA complex. 

This capability supports nuclear weapons and other national security missions, including prototyping and 

parts development, the full lifecycle requirements of power source components through early-stage R&D 

and modeling, technology maturation, design and development, production, surveillance, and 

disassembly. 

Neutron Generators

Neutron generators are highly complex LLCs integral to nuclear weapon function. The DOE/NNSA neutron 

generator enterprise, which is an integrated design and production agency, manages the neutron 

generators’ entire lifecycle to meet DOE/NNSA’s requirements, including scientific understanding through 

design, development, qualification, production, surveillance, dismantlement, and disposal.

2.1.3.2 Integrated Surety Architecture

The Integrated Surety Architecture program enhances DOE/NNSA transportation surety for over-the-road 

shipments of nuclear weapons by developing enhanced capability shipping configurations to support 

transportation security. The program is implementing enhanced capability shipping configurations to 

address the maximum number of future shipments. Integrated Surety Architecture is a DOE/NNSA 

requirement for over-the-road shipment of any nuclear weapon planned to be in the active stockpile after 

2025.1

2.1.3.3 Sentinel Integration

The W87-0 will be the first warhead deployed on the LGM-35A Sentinel, formerly known as the Ground 

Based Strategic Deterrent. This effort will require extensive qualification and integration activities to 

ensure the W87-0 will function as designed in the new Sentinel environments. In addition to ground and 

flight tests, warhead subsystem production will ramp up to replace hardware consumed in Sentinel 

qualification.

2.2 Stockpile Major Modernization

Stockpile major modernization activities are performed through a 

series of planned LEPs, Mods, Alts, and warhead acquisition programs 

enabled by a strong set of science, technology, engineering, and 

production capabilities. Figure 2–2 displays these plans, which fully 

reflect the priorities established and formally authorized by the 

Nuclear Weapons Council. Some modernization programs do not yet 

have approved first production units but reflect notional first 

production units, coordinated with DoD, for planning purposes.

1 Stated in 50 U.S. Code § 2538 (d).

Stockpile Major Modernization 

Accomplishments

• W80-4 completed the first flight 

test on the Long Range Standoff 

cruise missile.
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Figure 2–2. DOE/NNSA Warhead Activities

Currently, the long-term vision for the nuclear weapons stockpile seeks to build additional flexibility for 

the Nation to enable rapid response to unforeseen contingencies, while incorporating features and 

technologies that enhance safety and security, as appropriate and practicable. DOE/NNSA will 

incorporate flexibility-enabling design strategies and manufacturing, an advanced digital enterprise that 

promotes system modernization activities, and exercise capabilities through the Stockpile Responsiveness 

Program (see Appendix D). These improvements will enhance the Nation’s ability to counter adversaries’ 

capabilities, stockpile aging, and variables associated with supporting U.S. hedge capabilities.

Qualified options for materials, components, and systems must be developed to meet resilience 

requirements for the U.S. nuclear deterrent, and matured in advance to be viable for consideration and 

available when needed to support down-select decisions, development, and production. The activities 

that lead to this state of readiness depend on advanced scientific and engineering capabilities that enable

design, qualification and certification processes, and improve the responsiveness of the nuclear security 

enterprise in terms of cycle time and digital design tools. These science-based enabling efforts are 

described in Chapter 4.

2.2.1 Phase X Process (Nuclear Weapons Life Cycle)

The responsibilities of DoD and DOE/NNSA for the development, testing, and production of proposed 

nuclear weapons were originally established through the 1953 joint agreement between the Atomic 

Energy Commission and DoD, which introduced the concept of weapon acquisition phases.

Nuclear weapons have been historically developed, produced, maintained, retired, and dismantled in a 

process known as the Nuclear Weapons Life Cycle (now known as the Phase X Process). The seven-phase 

process includes procedures for program study, development, production, sustainment, and nuclear 

weapons systems dismantlement and has not been exercised in its entirety since the end of the Cold War, 

with the United States executing only Phases 6 and 7 in recent decades. During this time, the Nuclear 

Weapons Council approved the Phase 6.X Process for non-routine Alts, Mods, and LEPs, which defines the 

framework for refurbishment activities of existing nuclear weapon systems. This process uses the same 

phases from the Nuclear Weapons Life Cycle, all occurring during Phase 6 of the weapon’s lifecycle. Until 

Key:

Studies and Engineering Production Last Production Units for the W80-4, W87-1, and W93 are still to be determined

 Alt = Alteration CHE = conventional high explosive FPU = first production unit FY = fiscal year LEP = life extension program

26 47

Phase X/6.X Process and the

Stockpile Modernization Program

23 24 25 27 28 29 30 31 32 35 36 37 38

W87-1 Modification Program

(formerly W78 Replacement Warhead)

45 46 48 (Activities at Pantex and Y-12)

B61-12 LEP

Tactical/Strategic Bomb

W88 Alt 370 / CHE Refresh

Submarine-Launched Ballistic Missile Warhead

W80-4 LEP

Cruise Missile Warhead

33 34 39 40 41 42 43 44

W93

Submarine-Launched Ballistic Missile Warhead

Future Strategic Land-Based Warhead (FSLW)

(Enables replacement of W87)

Future Strategic Sea-Based Warhead (FSSW)

(Enables replacement of W88)

Future Air-Delivered Warhead (FAW)

Submarine Launched Warhead

(Enables replacement of the W76-1/2)

6.6

6.3-6.5 6.6 

6.3-6.5 6.6

Notional FPU

Early 2030s

Notional FPU

Mid 2030s

FPU

FY 2027

6.6

Fiscal Years

Notional FPU

To Be Determined

Notional FPU

To Be Determined

Notional FPU

To Be Determined

Notional FPU

To Be Determined

Threat Assessments

&

Design Activities including

Commonality, Diversity, etc.

Phase X Process

(Phase 1 - Phase 5) Phase 6
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recently, all DOE/NNSA’s Major Stockpile Modernization activities have been guided by the Phase 6.X 

Process.

Emerging DoD requirements for future systems necessitated updated procedural guidelines defining the 

full seven-phase Phase X Process, which revised the original agreement and the joint DoD and DOE/NNSA 

procedures governing the full lifecycle for nuclear weapons. The new process is being used for the first 

time on the W93 program. These phases, and the relationship between the Phase 6.X Process and the 

Nuclear Weapons Life Cycle, are shown in Figure 2–3.

Figure 2–3. Phase X and Phase 6.X Processes

2.2.2 B61-12 Life Extension Program

The B61-12 LEP addresses multiple components that are nearing end-of-life, in addition to military 

requirements for reliability, service life, field maintenance, safety, and use control. The life extension 

scope includes refurbishment of nuclear and non‐nuclear components and incorporates component reuse 

where possible. With the addition of an Air Force-procured tail

kit assembly, the B61‐12 LEP will consolidate and replace the 

B61-3, -4, and -7 bomb variants.

2.2.2.1 Status

DOE/NNSA delivered the B61-12 LEP first production unit in 

November 2021, and received authorization to enter Phase 6.6,

Full-Scale Production, in June 2022. The B61-12 LEP also 

reached the 50 percent completion milestone for all remaining 

DOE/NNSA achieved the first production unit for 

the B61-12 LEP on November 23, 2021
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components, including canned subassembly production in fiscal year (FY) 2023. The program met DoD 

shipment delivery requirements in 2022 and is projected to maintain all shipments in future years. The 

B61-12 LEP released an Aircraft Compatibility Control Document documenting compatibility certification 

with the F 15E, B-2A, F-35A, F 16, and PA-200 and is continuing certification activities for the B-21. The 

program is scheduled to complete production and close out in FY 2026.

2.2.3 W88 Alteration 370 Program

The W88 warhead has been deployed for more than three decades, and several updates are required to 

address aging issues and to maintain readiness. The W88 Alt 370 Program modernizes the arming, fuzing, 

and firing subsystem; improves surety; replaces the conventional high explosive and associated materials; 

and incorporates a lightning arrestor connector, trainers, joint test assemblies, and associated handling 

gear. The W88 Alt 370 conversion is scheduled to run concurrently with LLC exchanges of GTSs and

neutron generators. This program does not extend the life of the warhead.

2.2.3.1 Status

The W88 Alt 370 completed the system-level first production unit in July 2021 and conducted the final 

review of the Design Review and Acceptance Group in October 2021. The Nuclear Weapons Council 

formally accepted the W88 Alt 370 into the stockpile in December 2021 and authorized entrance to 

Phase 6.6 in June 2022. In 2022, DOE/NNSA delivered an initial operational capability (quantity of re-entry 

Body Assemblies) of W88 Alt 370s to the Navy and continues to meet all scheduled deliveries.

2.2.4 W80-4 Life Extension Program

The W80-4 LEP will deploy with the Air Force’s AGM-181 Long Range Standoff (LRSO) cruise missile. This 

integrated program will replace the aging AGM-86 air-launched cruise missile and the W80-1 warhead. 

The LRSO cruise missile will improve the Air Force’s capability to defeat adversary Integrated Air Defense 

Systems by enhancing the bomber force’s delivery and survivability capabilities.

2.2.4.1 Status

In FY 2024, the W80-4 LEP will be in Phase 6.4, Production Engineering, maturing to final design and 

transitioning the warhead design into the manufacturing process. A Nuclear Explosive Safety Design 

Review was completed, providing feedback to optimize nuclear safety aspects of the W80-4 design and 

operational concepts at the Pantex Plant. The W80-4 LEP is on track to meet a first production unit in 

FY 2027. FY 2024 deliverables include: 

◼ Continuing joint flight tests with the Air Force LRSO program supporting the warhead design

◼ Updating military characteristics and stockpile-to-target sequence

2.2.5 W87-1 Modification Program

The W87-1 will be deployed on the LGM-35A Sentinel, formerly known as the Ground Based Strategic 

Deterrent, which will initially be fielded with the W87-0. The W87-1 will replace the aging W78 warhead 

by modifying the existing, legacy W87-0 design. After the B61-12 achieves initial operational capability, 

the W78 warhead will become the oldest weapon system in the stockpile and W78 components continue 

to age. The W87-1 Mod will meet DoD and DOE/NNSA requirements for performance, safety, reliability, 

and security and is slated to deploy on the Sentinel between FY 2031 and FY 2032.
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2.2.5.1 Status

In FY 2022, the program completed the Weapon Development Cost Report as well as set the initial 

program baseline in October 2022. A Nuclear Explosive Safety Design Review was completed in FY 2022, 

providing feedback to optimize nuclear safety aspects of the W87-1 design. The program achieved 

Nuclear Weapons Council approval to enter Phase 6.3, Development Engineering, in May 2023 and the 

W87-1 system conceptual design review was completed in December 2022.

2.2.6 W93 Program

The W93 will address future Navy ballistic missile requirements. It will incorporate modern technologies 

to improve safety, security, and flexibility to address future threats and will be designed for ease of 

manufacturing, maintenance, and certification. All key nuclear components will be based on currently 

deployed and previously tested nuclear designs, and extensive stockpile component and materials 

experience. It will not require additional nuclear explosive testing to certify. The program will use the 

Phase X Processfor integrated nuclear weapons system acquisition, rather than the Phase 6.X Process(see 

Section 2.2.1 for additional information regarding these lifecycle processes). The W93 program is 

currently in Phase 2, Feasibility Study and Design Options, which evaluates warhead architectures and 

available technologies against a potential range of desired attributes, draft military characteristics, and 

known constraints. It will also inform DoD’s program activities for the associated Mk7 reentry body within 

which the W93 would be deployed.

2.2.6.1 Status

The W93 completed Phase 1, Concept Assessment, in FY 2022. The Nuclear Weapons Council authorized 

the program to proceed into Phase 2, Feasibility Study and Design Options, in May 2022.

2.2.7 Future Warheads

DOE/NNSA is coordinating with DoD to define the appropriate warheads to support anticipated future 

threats. These warheads currently include the Future Strategic Land-Based Warhead, the Future Strategic 

Sea-Based Warhead, the Future Air-Delivered Warhead, and a Submarine-Launched Warhead (to replace

the W76-1/2).

2.3 Weapon Dismantlement and Disposition

WDD activities disassemble retired weapons into major 

components. Those components are then assigned for reuse, 

storage, surveillance, or for additional disassembly and 

subsequent disposition of constituent parts and materials.

The dismantlement schedule for retired nuclear weapons is 

planned to provide the materials and components required 

for the stockpile (in particular, LEPs, Mods, and Alts), and 

considers the needs of other programs for these materials.

WDD also maintains the proficiency of technicians and 

balances work scope at the production sites.

Dismantlement rates are affected by many factors including 

weapon system complexity, availability of qualified personnel, equipment, and facilities, logistics, policy

and directives, and legislative requirements. DOE/NNSA’s current 7-year Dismantlement Plan balances 

physical constraints with legislative, policy, and directive guidance. The WDD work scope includes 

Weapons Dismantlement and Disposition 

Accomplishments

• Provided materials and components on 

schedule to meet stockpile sustainment and 

modernization requirements

• Provided materials to meet commitments to 

Naval Reactors

• Met or exceeded component 

characterization and disposition goals
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management of retired nuclear weapon systems (e.g., managing safety concerns), characterization of 

weapon components, disassembly of weapons and components, and final component disposition (e.g., 

component reuse and material recycle and recovery). WDD activities occur across all sites in the nuclear 

security enterprise.

2.3.1 Status

DOE/NNSA continues to dismantle retired weapons and disposition resulting components and materials, 

supporting DoD return schedules, and meeting the needs of the LEPs and material demand requirements. 

As detailed in the FY 2024 SSMP’s classified annex, the DOE/NNSA plans to dismantle several weapons 

systems to meet downstream requirements for material and/or weapon parts and DOE/NNSA is on-track 

to meet these responsibilities. Moreover, DOE/NNSA’s disposition schedules are on-track and several 

disposition projects are ahead of schedule. DOE/NNSA also developed return schedules to remove 

additional retired weapons from DoD facilities, while still meeting DoD operational requirements. WDD 

continues to characterize components coming off the dismantlement line, and sites are eliminating excess 

component inventories.

2.4 Production Operations

Production Operations provides the base capabilities to enable 

weapon operations (assembly, disassembly, and production) 

planned for the warhead modernization, sustainment, and the WDD

programs. Production Operations’ goal is to maintain the base 

capability required to sustain the stockpile through robust 

management and production process engineering, manufacturing, 

production technology resources, and production equipment 

maintenance. The program accomplishes this goal by maintaining 

the tools and personnel necessary for supporting major 

manufacturing, assembly, disassembly, maintenance, and 

production data management for all nuclear weapons in the 

stockpile and modernization efforts.

At individual enterprise sites, Production Operations sustains capabilities at required capacities for the 

nuclear security enterprise’s production mission, mainly through the multifaceted skilled labor force. The 

program provides the base labor capacity that is essential for preventive and corrective production 

equipment maintenance, calibrations, quality assurance, qualification, production logistics, 

manufacturing execution systems, process flow, and scheduling activities.

Production Operations maintains critical multi-weapon system supporting equipment at certain sites and 

select programmatic infrastructure. Production Operations also provides the input for the modernization 

of production capabilities to improve efficiency and maintain manufacturing operations to meet future 

requirements. The program heavily depends on infrastructure modernization to ensure base capabilities 

with adequate capacities, space, and equipment are in place.

2.4.1 Status

Production Operations is expanding the nuclear security enterprise’s base capability to provide the 

increased capacity necessary to meet the ramp up in stockpile modernization activities and Production 

Modernization projects. Production Operations has also assumed additional scope associated with 

Production Operations 

Accomplishments

• Maintained production equipment at 

98 percent availability

• Completed over 78,000 equipment 

and tooling calibrations

• Executed Tritium Process 

Computing maintenance in support 

of LLC exchange GTS production 

at 100 percent

•
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enterprise capacity modeling and planning to ensure future capacities align with the increasing demand 

signal.

2.5 Nuclear Enterprise Assurance

NEA ensures the nuclear security enterprise actively manages 

subversion risks to the nuclear weapons stockpile and associated 

design, production, and testing capabilities. Through nuclear weapon 

digital assurance, NEA enables risk-managed adoption of leading-edge 

technologies to meet emerging military requirements and reduce 

modernization schedules and costs.

NEA focuses on technical and governance activities for the assurance of digital systems integral to weapon 

systems, operational technologies directly related to weapons, and capabilities that cross-cut multiple 

weapons programs. The NEA program has four major activities:

1. Assurance Evaluations

2. Tools and Capabilities

3. Policy, Requirements, and Oversight

4. Workforce Standards

2.5.1 Status

In FY 2022, NEA established the foundation for cross-site, multi-disciplinary assurance capability. Progress 

was made establishing, updating, and expanding NEA training as well as instituting cybersecurity of 

nuclear weapon policies, requirements, and oversight. For more information on NEA, see the classified 

annex of this SSMP.

Nuclear Enterprise Assurance

Accomplishments

• Established formal program of 

record
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-1

Chapter 3

Production Modernization

The Production Modernization program is responsible for modernizing the facilities, infrastructure, 

technologies, and production methods to meet stockpile requirements. The program encompasses five 

major subprograms that sustain the Nation’s nuclear weapons stockpile and deterrent:

1. The Primary Capability Modernization program consolidates management of primary stage material 

processing and component production capabilities in the Department of Energy’s National Nuclear 

Security Administration’s (DOE/NNSA) nuclear security enterprise. The program includes 

(1) Plutonium Modernization and (2) High Explosives and Energetics Modernization.

2. The Secondary Capability Modernization program restores and increases manufacturing capabilities 

for the secondary stage of nuclear weapons in the nuclear security enterprise. This program is 

modernizing facilities and operations to process the materials, fabricate components, and assemble 

components into subassemblies. The program includes (1) Uranium Modernization, (2) Depleted 

Uranium (DU) Modernization, and (3) Lithium Modernization. 

3. The Tritium Modernization and Domestic Uranium Enrichment (DUE) Program consists of two parts: 

(1) Tritium Modernization produces, recovers, and recycles tritium to support national security 

requirements and (2) DUE ensures a reliable supply of enriched uranium to support U.S. national 

security needs. 

4. The Non-Nuclear Capability Modernization program modernizes the capabilities needed for the 

design, development, qualification, production, and surveillance of non-nuclear components for 

multiple weapon systems.

5. The Capabilities-Based Investments (CBI) Program executes projects for equipment, tools, supporting 

facilities, and infrastructure directly related to enduring, multi-program weapon activity capabilities, 

mission deliverables, and management of programmatic risk across the nuclear security enterprise. 

3.1 Primary Capability Modernization

The Primary Capability Modernization Program consolidates management of primary stage material 

processing and component production capabilities in the nuclear security enterprise. The program 

includes (1) Plutonium Modernization and (2) High Explosives and Energetics Modernization. 

3.1.1 Plutonium Modernization

The United States is restoring the capability to produce new primaries for nuclear weapons, including 

plutonium subcomponents such as pits. In May 2018, the NNSA Administrator provided Congress with 

DOE/NNSA’s course of action to produce no fewer than 80 pits per year (ppy) as required by the National 

Defense Authorization Act for Fiscal Year 2018. DOE/NNSA’s strategy to meet pit production 

requirements, endorsed by the Nuclear Weapons Council, is twofold:
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Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-2

◼ Continue to invest in the Los Alamos National Laboratory 

(LANL) to produce 30 ppy

◼ Repurpose the former Mixed Oxide Fuel Fabrication 

Facility at the Savannah River Site (SRS) as the Savannah 

River Plutonium Processing Facility (SRPPF) to produce 

50 ppy

This two-pronged approach will restore a critical production 

capability central to maintaining the Nation’s nuclear deterrent. 

Operating two geographically separated plutonium pit production 

facilities provides resilience and adaptable options to mitigate

against shutdowns, incidents, or other risks that may affect 

operations at a single site. 

Recapitalizing the Nation’s pit production capability to enable 

production of no fewer than 80 ppy addresses two major drivers:

◼ Department of Defense (DoD) and DOE/NNSA 

requirements to enhance warhead safety and security

◼ Risk mitigation against plutonium aging through 

deliberate, methodical replacement of older plutonium 

pits with newly manufactured pits

3.1.1.1 Status

In addition to dedicated pit production infrastructure efforts at 

LANL and SRS, DOE/NNSA is recapitalizing existing facilities 

throughout the nuclear security enterprise through a series of 

reinvestment projects, including several line-item projects, to 

replace the aging infrastructure that supports capabilities to

process plutonium, fabricate plutonium components, perform 

experiments, and disposition transuranic waste. These 

projects include the Chemistry and Metallurgy Research 

Replacement project, which maintains continuity in analytical 

chemistry and material characterization capabilities by 

transitioning these activities from the Cold War-era Chemistry 

and Metallurgy Research facility to newer facilities. Programs are also conducting risk reduction activities 

in material recycle and recovery by removing the nuclear material inventory currently housed in the 

Chemistry and Metallurgy facility. 

3.1.1.2 Los Alamos National Laboratory Plutonium Modernization

A modern, responsive, and resilient capability to handle, process, and characterize plutonium is essential 

to assess and maintain the nuclear weapons stockpile. A responsive plutonium infrastructure requires 

proper storage facilities, safe and secure disposal pathways, and unique facilities for research and 

development (R&D) and design realization activities. Manufacture and surveillance of plutonium 

components, as well as performance of experiments, analysis of plutonium, and plutonium processing for 

the nuclear weapons program (e.g., recovery, characterization, component fabrication, nondestructive 

analysis, and surveillance) currently occur at LANL’s Plutonium Facility (PF-4). Modernization activities 

concentrate on initiatives within PF-4, such as recapitalization and modernization of the equipment 

needed to restore PF-4’s ability to produce WR pits. Ongoing activities include projects funded by the 

Plutonium Modernization

Major Accomplishments

• Lawrence Livermore National 

Laboratory (LLNL) commenced 

certification testing on the LANL 

produced Certification 03 build. 

• LANL completed seven developmental 

pit builds in 2022.

• SRPPF approved the Dismantle and 

Removal Critical Decision (CD)-3A 

package for the main process building 

to start critical activities to prepare the 

building for the construction needed to 

establish its new pit production mission.

• Kansas City National Security Campus 

(KCNSC) began providing War Reserve 

(WR) quality components to LANL to 

support the reestablishment of pit 

manufacturing in the United States.

Molten Plutonium in Cast
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-3

Plutonium Modernization Program and line-item programs, such as the Los Alamos Plutonium Pit 

Production Project, which will increase the pit manufacturing capability to 30 ppy and maintain LANL as 

the Nation’s Plutonium Center of Excellence for R&D. 

Primary infrastructure investment for the Plutonium Modernization program at LANL include:

◼ Los Alamos Plutonium Pit Production Project

◼ Technical Area (TA)-55 Reinvestments Project, Phase 3

◼ Transuranic Liquid Waste Facility

◼ Chemistry and Metallurgy Research Replacement Project 

To meet rate production goals, workforce increases are needed. 

Therefore, DOE/NNSA must hire, train, qualify, and retain additional pit 

production personnel to meet the requirements. This increased 

workforce will need additional support, such as infrastructure 

investments for operations support, waste management, offices, parking, 

training, etc. 

To support pit production and other vital plutonium missions, LANL has 

transitioned to 24/7 facility availability to enable enhanced execution of 

programmatic work, facility maintenance, equipment installation, and 

construction activities. 

Plutonium Modernization also supports manufacturing of precision plutonium devices for scientific

evaluation and experiments, including sub-critical experiments. The data collection and analysis from this 

evaluation supports sustaining an overall healthy feedstock supply chain that will support plutonium 

processing for the nuclear weapons program. 

3.1.1.3 Savannah River Site Plutonium Modernization

SRS will establish a pit production capability in an existing facility that is already designed to meet stringent 

security and safety requirements for plutonium operations. Initial modernization activities include 

repurposing and transitioning into a safe, secure, compliant, and efficient pit production facility, the 

planned SRPPF. A new program office at SRS to sustain an enduring pit production goal of 50 WR ppy is

being established. The Critical Decision (CD)-1 (Approve Alternative Selection and Cost Range) package 

detailing the conceptual design and estimated cost range was approved in fiscal year (FY) 2021. Following 

CD-1 approval, the project team has continued to finalize the specific conceptual design for process 

operations. In parallel, the team has continued to develop a detailed, more risk-informed design 

performance baseline, aligned to a Program Requirements Document. Based on information developed 

to support the CD-1 approval, DOE/NNSA determined that achieving the required 50 WR ppy production 

rate at SRS in 2030 was not feasible. Establishing the required SRPPF pit production capacity as close as

possible to 2030 remains a high priority and is required for sustaining the effectiveness of the Nation’s 

nuclear deterrent.

There are several key steps to completing the SRPPF project and establishing an enduring capability:

◼ Complete six inter-related construction subprojects 

◼ Hire and train the workforce necessary to establish and sustain the SRS pit production mission

◼ Establish the institutional systems at SRS necessary to build WR pits

◼ Establish and manage SRS pit production interfaces across the nuclear security enterprise

TA-55 Cold Lab Simulated 

Waste Removal
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◼ Maintain a secure supply chain to support the SRS 

pit production mission

◼ Modernize SRS site-wide infrastructure that 

supports the pit production mission

The following upcoming activities will allow DOE/NNSA to 

define timelines for 50 WR ppy at SRPPF: 

1. Completion and approval of SRPPF’s CD-2 

(Approve Performance Baseline) acquisition 

milestone. This indicates that the project’s design 

is 90 percent complete and will identify when fully

operational capability (CD-4) can be achieved.

2. Lawrence Livermore National Laboratory (LLNL), 

LANL, Kansas City National Security Campus 

(KCNSC), and the ongoing W87-1 Modification 

Program’s Pit Product Realization Team to find 

ways to reduce the time needed to produce the first WR pit at SRPPF after CD-4, based on 

knowledge gained at LANL from parallel production efforts at PF-4.

3. Capture efficiencies and use lessons from production experience at LANL to apply at SRPPF.

Further activities conducted in support of CD-2 have identified opportunities to accelerate achieving the 

required production capacity.

Essential to this process will be the transition of an existing facility into the SRS High Fidelity Training and 

Operations Center, which began with design work in FY 2021. The High Fidelity Training and Operations 

Center will enable training in a safe environment, as well as high-fidelity surrogate materials training 

aimed to qualify the personnel and procedures ultimately used to build and handle pits in the SRPPF. The 

High Fidelity Training and Operations Center will also support final design by serving as a test bed for 

selected engineering equipment and to demonstrate systems integration. LANL and LLNL are supporting 

the training rotation pipeline for the SRS pit production mission through a knowledge transfer program 

initiated in FY 2020 with Savannah River National Laboratory. Additionally, a CD-3A package for 

dismantlement, removal, and site preparation was approved in August 2022 to begin removal of 

unnecessary equipment, commodities, and coatings from the existing facility and procurement of 

temporary support equipment, which will maximize beneficial use of the inventory turned over from 

Mixed Oxide Fuel Fabrication Facility materials and equipment.

3.1.1.4 Enterprise Plutonium Support

DOE/NNSA manages numerous facilities that house plutonium handling, processing, R&D, 

characterization, experimentation, and storage facilities that must be sustained. A responsive plutonium 

infrastructure requires proper storage facilities, safe and secure disposal pathways, and unique 

equipment and facilities for R&D and design realization activities.

Enterprise Plutonium Support includes activities that enable programmatic objectives across the 

enterprise, including production of non-nuclear components, certification activities, management of the 

Product Realization Team, material management activities, radioisotope thermoelectric generator 

production and surveillance, subcritical plutonium experiments, and pit certification.

SRPPF 3D Aerial with New Buildings
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3.1.1.5 Challenges and Strategies 

Table 3–1 provides a high-level summary of Plutonium Modernization challenges and the strategies to 

address them. 

Table 3–1. Summary of Plutonium Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Reestablishing required pit production 

capabilities and capacity with timely 

integration of infrastructure and 

workforce investments in alignment 

with W87-1 program needs.

Continue to invest in LANL plutonium facilities 

and workforce needs to meet pit production 

milestones—achieving the first production unit 

milestone, then completing the Los Alamos 

Plutonium Pit Production Project to increase 

production capacity to 30 WR ppy.

Drive continued improvement in 

executing equipment installation 

projects and workforce 

investments to support future pit 

production needs. 

Repurposing the former Mixed Oxide 

Fuel Fabrication Facility at SRS to 

achieve a production rate of 50 WR 

ppy.

• Implement a tailored approach for the SRPPF 

project to achieve CD-2/-3 and execute 

engineering, procurement, and construction 

activities through multiple subprojects to 

support producing 50 WR ppy.

• Use knowledge transfer from LANL and LLNL 

SMEs to support workforce development at 

SRS to achieve pit production mission 

objectives.

Maintain a supply chain for 

weapons-related components and 

commodities needed to support 

the 50 WR ppy mission.

Executing environmental 

testing/surety/qualification of 

plutonium pits without nuclear 

explosive testing.

• Use and expand chemical, thermal, and 

mechanical characterization capabilities to 

evaluate newly manufactured and legacy 

pits.

• Expand and establish new equipment and

experimental platforms to evaluate normal 

and abnormal environments that pits could 

experience.

• Leverage scientific capabilities described in 

Chapter 4 to evaluate newly manufactured 

material.

Leverage ongoing investment in 

the Enhanced Capabilities for 

Subcritical Experiments Program 

to support estimates of the 

certification uncertainty achieved 

with single and multi-point safety.

Managing glovebox fabrication and 

deliveries to support enterprise needs.

• Establish a working group to analyze demand 

and current industrial capacity and work with 

national lab partners to prioritize

procurements. 

• Examine current procurement methods to 

streamline processes.

Work with interagency and

industry partners to communicate 

growing need for gloveboxes and 

increase capacity.

CD = Critical Decision

ppy = pits per year

SMEs = subject matter experts

SRPPF = Savannah River Plutonium Processing Facility

WR = War Reserve

3.1.2 High Explosives and Energetics Modernization

The High Explosives and Energetics Modernization program addresses nuclear security enterprise

modernization of high explosives (HE) science and production facilities and the qualification of energetic 

materials (energetics) such as HE, pyrotechnics, and propellants. This program is not only responsible for 

energetic materials, but also the network of associated activities, such as the HE and Energetics business 

processes, infrastructure, production, and supply chain. This program scope spans five management and 

operating sites: the Pantex Plant (Pantex), Sandia National Laboratories (SNL), LANL, LLNL, and the Nevada 
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National Security Site (NNSS). Each site maintains 

multiple dispersed facilities engaged in Stockpile 

Research, Technology, and Engineering and Production 

Operations. 

Energetic materials are an essential component for 

each weapon system in the existing stockpile. In 

addition to existing stockpile sustainment needs, 

currently planned warhead modernization activities

(such as limited life component exchanges) and future 

modernization activities will continue to have a 

substantial demand for energetics. DOE/NNSA meets 

energetic material demands for nuclear weapon 

sustainment and modernization through investments

in developing reliable production capabilities such as:

safe and secure facilities, integrated infrastructure,

effective logistics (handling, storage, and delivery), and 

ensuring a reliable supplier base. 

3.1.2.1 Status

Most of the current facilities in the energetics 

enterprise were built over 70 years ago. These aging

facilities require extensive infrastructure and process 

modernization to meet future mission requirements.

DOE/NNSA is currently planning three major 

programmatic line-item construction projects for HE

along with additional ongoing investments across the 

HE and energetics enterprise: 

◼ The HE Science and Engineering (HESE) Facility 

at Pantex will consolidate 15 aging facilities into three new, efficient facilities to conduct science, 

technology, engineering, and production activities in weapons assembly/disassembly and HE. 

This will mitigate against current HE production and testing capability risks.

◼ The HE Synthesis, Formulation, and Production project at Pantex will address explosive and mock 

formulation operations to support multiple weapon 

programs; technology development for future 

programs; and support for strategic partners that will 

hedge against current HE production and testing 

capability gaps.

◼ The Energetic Materials Characterization Facility at 

LANL will consolidate 18 inadequate and outdated 

facilities to analyze, test, and periodically qualify HE 

parts going into or coming from stockpile systems. 

Once built, program activities at this facility will identify 

solutions to advance predictive capabilities for safety 

and performance assessments, qualification, and 

surveillance; evaluate material responses to all phases 

of the stockpile-to-target sequence; resolve significant finding investigations (SFIs) involving 

High Explosives and Energetics Modernization 

Accomplishments

• Implemented projects to modernize HE qualification 

and production facilities (HE Science and 

Engineering; and Light Initiated High Explosives 

facility).

• Achieved qualification of development lot 1 for the 

W87-1 toward main charge production.

• Completed pressing and machining operations in 

advance of the W87-1 qualification of legacy LX-17.

• Established HE and energetic requirements to meet 

W93 development and qualification requirements.

• Developed supply chain continuity of operations 

models and risk registers to inform risk mitigation 

decisions.

• Enhanced safety and viability of storage and shipping 

energetic materials, including testing to characterize 

hazards for Department of Transportation 

compliance.

• Completed our Energetics Industrial Base 

Assessment to identify available vendors and map 

their supply chains to determine vendor capability to 

convert to domestic production.

• Re-establishing production capability and processes 

for critical energetic materials.

• Sponsored an Other Transaction Agreement to 

construct a TATB (triaminotrinitrobenzene)

production facility at the Naval Surface Warfare 

Center, Indian Head Division, to manufacture 

insensitive HE for NNSA.

HESE HE Lab Blast Tank Pit Concrete Forming
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energetic materials; provide technical data on which to base annual weapon assessments; and 

develop new/replacement materials to support evolving HE technical requirements. It will also 

provide support in the design and testing of new detonators, as well as the development of HE 

formulation and explosive components for the future stockpile. This facility will create a 

consolidated set of capabilities for the development of components and materials from early 

concept and prototype design to high-volume production within a single location and provide 

internal production capability for WR energetic material and components (such as actuators, 

drivers, detonators, timers, and rocket motors) to augment the commercial supplier base.

◼ Additionally, ongoing investment in Light-Initiated High Explosive capabilities at SNL will provide 

the ability to conduct testing of full-scale mockup devices with live main charges in safe and 

effective modern facilities. These investments provide HE qualification capability to hostile 

impulse requirements.

Future infrastructure investments may include consolidation and modernization of existing facilities 

critical to providing required HE capabilities for main charges, boosters, and detonators in a modern, 

enhanced safety and security environment. DOE/NNSA will continue to pursue projects to mitigate known 

issues with the limited commercial component supplier base and provide onsite production of energetic 

materials and components for the stockpile. 

HE and Energetics Modernization activities will also include the following:

◼ Manage the HE and energetics supply chain risk portfolio to ensure a healthy infrastructure exists 

to maintain, manufacture, and deploy WR HE and energetics in support of weapons production

◼ Provide guidance for energetics surveillance, weapon response, transportation, containers, and 

explosive/electrical environments

◼ Define and monitor the qualification standards of HE and energetic material

◼ Support the future of HE and energetics development, production, component design, and 

manufacturing, testing, and qualification

Experienced and knowledgeable personnel are needed for the proper care and handling of hazardous 

components. Recruitment of skilled professionals and extensive safety training are imperative for safe 

operations. With an increased workload and the attrition or retirement of senior personnel, DOE/NNSA 

must actively develop a sustainable workforce to perform these operations competently and safely in the 

future. More detail on DOE/NNSA’s workforce strategies can be found in Chapter 7 of this report.

3.1.2.2 Challenges and Strategies

Table 3–2 provides a high-level summary of HE and Energetics Modernization challenges and the 

strategies to address them.

Table 3–2. Summary of High Explosives and Energetics Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Nuclear security enterprise 

infrastructure for energetic 

materials science, production, and

development located within aging 

critical facilities and equipment 

(many past their life expectancies).

• Coordinate with the Office of 

Infrastructure and the Programmatic 

Recapitalization Working Group to 

improve energetic readiness. 

• Keep aging equipment available for 

warhead modernization and current 

stockpile systems through rigorous 

maintenance programs and integrated 

• Transfer manufacturing and 

qualification of energetic and HE 

materials to the HE Synthesis, 

Formulation, and Production Facility, 

the HESE Facility, and the Energetic 

Materials Characterization Facility.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

equipment modernization planning 

across the nuclear security enterprise. 

• Find creative solutions to modernize 

facilities past their useful life until current 

modernization efforts are complete.

• Make short- to medium-term 

investments where reasonable.

• Engage and enable sites to reduce 

dependency or better enable external 

suppliers.

• With inputs from sites, define 

requirements, risks, and capability gaps 

to inform future investments.

• Employ creative methods to mitigate 

obsolescence issues, such as using 

additive manufacturing to produce 

parts.

• Stand up production enclaves, as DA-PA

partnerships, to enable more efficient 

response to the emerging deterrent. 

Depending on a small and shrinking 

vendor base to supply the 

explosives, constituent 

components, and specialized 

equipment needed to produce its 

energetic end products.

• When necessary, use in-house capabilities 

to restore mission schedules at risk.

• Respond to situations by collaborating 

with relevant stakeholders to develop 

innovative solutions that may stabilize 

suppliers or qualify new 

materials/supplies. 

• Support cooperative arrangements with 

DoD and Holston Army Ammunition Plant

(Holston) to improve Holston’s ability to 

deliver product requirements.

• Sponsor capital acquisition projects and 

coordinate efforts among sites and HQ 

elements to shepherd projects from 

business case to beneficial use.

• Construct the HE Synthesis, 

Formulation, and Production Facility for 

a nuclear security enterprise capability

and capacity to supply HE for WR 

energetics.

• Enable Naval Surface Warfare Center 

Indian Head Division to supply HE in the 

near term and operate as a second 

source to Holston for insensitive high 

explosive.

Developing sufficient supply chain 

capacity for energetic materials in 

current and future life extension 

programs and alterations.

• Exercise initiatives within the Defense 

Programs for Energetic Materials. 

• Refresh HE formulation, synthesis, and 

machining capabilities at Pantex. 

• Identify, assess, and perform riskinformed activities to understand, 

characterize, and develop better 

methods to produce and qualify materials 

more fully.

• Analyze and apply lessons learned from 

Defense Programs initiatives for 

energetic materials for broader 

implementation across the enterprise 

along lines of effort, such as at-risk 

materials, and requirements and 

capacity integration.

• Continue to build on external 

collaboration activities with external 

DoD stakeholders that further 

partnerships with industry to ensure 

supply chain opportunities are identified 

and assessed.

Ensuring requirements for 

energetic materials are adequately 

identified, preserved, and 

documented. 

Document the detailed processes necessary 

for the synthesis and formulation of 

energetic materials for a repeatable 

material specification that yields the 

required engineering and performance 

requirements through efforts with the 

NNSA Energetics Coordinating Committee.

• Document the technical basis for future 

process parameter choices and 

rationale for specific requirements in 

the specifications.

• Improve understanding and control over 

material specifications and 

manufacturing to improve reliability and 

repeatability and increase lot 

acceptance. Develop techniques to 

computationally assess manufacturing 

with computational fluid dynamics, 

computational chemistry, machine 

learning, and artificial intelligence.

• Develop techniques to reprocess out-ofspec material to meet requirements.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Mitigating material shortfalls for 

legacy WR HE due to a lack of 

robust plans and processes to 

control inventories. 

• Collaborate with DoD and industrial 

partners to institute a more routine 

process to exercise synthesis and 

formulation of energetic materials.

• Complete triaminotrinitrobenzene/PBX9502 specifications to improve plans and 

processes and enhance inventory control. 

Preserve and enhance in-house production 

for items such as WR detonator powder 

production.

Maintaining a trained and qualified 

a workforce for HE operations.

• Develop staffing plan for multi-year 

training operations. 

• Transfer knowledge from SMEs near 

retirement age to new SMEs.

Implement additional strategies to 

maximize knowledge retention and 

minimize workforce turnover.

DA-PA = design agency-production agency

HE = high explosives

HESE = High Explosive Science and Engineering Facility

SME = subject matter expert

WR = War Reserve

3.2 Secondary Stage Capability Modernization

The Secondary Capability Modernization Program is responsible for restoring and increasing 

manufacturing capabilities for the secondary stage to required levels in the nuclear security enterprise. 

This includes ensuring the availability of strategic materials and other sub-component streams necessary 

for the secondary stage, as well as modernizing the facilities and operations required to process these 

materials, fabricate them into parts, and assemble the final components. The areas of focus include 

(1) Uranium Modernization; (2) DU Modernization; and (3) Lithium Modernization.

3.2.1 Uranium Modernization

Highly enriched uranium (HEU) is needed to support stockpile programs, Naval Reactors, and 

Nonproliferation programs. Uranium Modernization supports these efforts through investments in the 

infrastructure surrounding HEU processing, purification, machining, and other operations. To execute this 

mission, Uranium Modernization is working to phase out mission dependency on Building 9212 at the 

Y-12 National Security Complex (Y-12) by the end of FY 2029, but the project is undergoing a federal 

rebaseline. To support the success of this transition, the program is working to:

◼ Relocate Building 9212’s HEU capabilities into the Uranium 

Processing Facility and other enduring facilities

◼ Leverage these relocations to develop and deploy new 

technologies to reduce cost, improve worker safety, and 

enhance manufacturing processes to meet future needs

◼ Invest in key production systems to sustain casting, 

machining, metal purification systems, assembly, and 

analytical chemistry capabilities to support long-term 

reliability

3.2.1.1 Status

Y-12 is home to the Nation’s primary uranium processing and storage infrastructure, including laboratory 

capabilities that supports uranium activities. Building 9212 contains the most hazardous HEU operations

but does not meet modern nuclear safety and security standards because it is nearly 80 years old. As part 

of the relocation strategy, modern capabilities will be deployed and existing processes will be simplified 

Uranium Modernization 

Accomplishments

• Demonstrated the technical readiness 

of electrorefining to purify HEU.

• Completed a years-long effort to 

remove more than 59 metric tons of 

material-at-risk from Y-12’s enriched 

uranium operations area and secured 

it in the modern HEU Material Facility.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-10

or phased out to increase the overall safety and efficiency of HEU operations. During the transition period, 

efforts to maintain a reduced level of material-at-risk will continue.

The Uranium Processing Facility will replace Building 9212 capabilities for HEU casting, special oxide 

production, chemical recovery, and decontamination. HEU casting and special oxide production will be 

housed in the Uranium Processing Facility’s Main Process Building, while chemical recovery, 

decontamination, and assay will take place in the Uranium Processing Facility’s Salvage and Accountability 

Building. A third building, the Uranium Processing Facility’s Mechanical/Electrical Equipment Building, will 

provide utilities and other support systems. Uranium Modernization is working with Y-12, the design 

laboratories, and other NNSA Offices within Defense Programs to reduce schedule and cost risk associated 

with the Uranium Processing Facility by demonstrating the effectiveness of microwave casting using a fullscale prototype system.

DOE/NNSA will relocate other Building 9212 capabilities, like HEU purification and machine chip 

processing, into an enduring facility—Building 9215. Ongoing projects, such as HEU electrorefining and 

direct chip melt, will relocate, reduce costs, and improve material processing technologies. The calciner 

technology being deployed in Building 9212 will allow for safe and efficient transition out of this facility.

These capabilities will also improve existing operations by reducing the number of production processes, 

reducing risks, and improving personnel safety.

Uranium Modernization also funds Technology Maturation efforts to develop and deploy improved 

manufacturing processes for nuclear weapon materials. When the technology is sufficiently mature, the 

development and deployment of equipment is pursued 

through capital line-item acquisition or major item of 

equipment processes, as appropriate. This technology 

development and maturation process has generated

three current major items of equipment acquisitions. The 

major items of equipment include:

◼ Electrorefining—an electrochemical HEU 

purification system designed to replace portions 

of the current HEU purification process. This 

capability, located in Building 9215, along with the 

calciner process in Building 9212, will allow for the 

shutdown of the current high-hazard wet 

chemistry process located in Building 9212. The program has already initiated the shutdown of 

the oxide conversion and reduction processes in Building 9212. The remaining portions of the 

hazardous purification process in Building 9212 will continue to operate at least until the 

completion of the Building 9212 Calciner. The program will perform its HEU metal purification 

using the electrorefining process after it achieves operational release in 2024. 

◼ Building 9212 Calciner—a dry thermal treatment process to convert low-equity HEU liquids to a 

dry stable form for storage. This capability will process material remaining in Building 9212 during 

the final clean-out of the facility. The calciner, along with the electrorefining capability (see 

above), will allow for the shutdown of the current high-hazard wet chemistry process in 

Building 9212.

◼ Direct Chip Melt—a process by which HEU machine tool chips (i.e., turnings) are recovered by 

collecting and remelting them in furnaces. This capability, located in Building 9215, will replace

the current high-hazard practices of transferring chips to Building 9212 for cleaning, briquetting, 

and storing.

The Electrorefining Development Area
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-11

Uranium Modernization continues to optimize Building 9212 resources to supply the current stockpile 

with purified HEU metal. The program provides a comprehensive storage capability to support a steady 

supply of material through peak production periods. It also enables HEU material de-inventory activities 

to increase safety, establish target working inventory levels for the production facilities, and optimize 

composition of the inventory. The program, partnering with DOE/NNSA’s Office of Environment, Safety, 

and Health, is also managing the sustainment of enduring facilities with an Extended Life Program, which 

implements risk-based infrastructure improvements on production facilities. This enables the safe and 

secure continuation of operations, including those relocated from Building 9212, through 2040 and into 

the future.

Uranium Modernization is proactively removing equipment that is no longer operationally necessary from 

these enduring facilities through its Flexible Production Capacity Initiative to improve Y-12’s 

responsiveness and resilience to meet future production needs.

3.2.1.2 Challenges and Strategies 

Table 3–3 provides a high-level summary of uranium modernization challenges and the strategies to 

address them. 

Table 3–3. Summary of Uranium Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Integrating new technologies into 

operations.

Develop and operate full-scale prototype 

systems to mitigate risks associated with 

technology maturation.

Use Operational Release Plans to 

identify issues and streamline the 

transition to operations. 

Executing process relocations with 

multiple timelines without 

interruption to operations.

Develop integrated schedule, risk plan, and 

lifecycle cost estimate. Relocate existing 

(radiography) and upgraded (direct chip 

melt, electrorefining) technologies in 

Building 9212 to enduring facilities, and 

install a calciner in Building 9212.

Bridge key capability gaps through 

partnership with commercial vendors 

and partnerships with other DOE 

laboratories.

Preparing Building 9212 for 

disposition and demolition in the

shortest achievable timetable.

• Begin deactivating systems and removing 

material immediately and maintain a 15+ 

year schedule.

• Reduce material-at-risk and overall 

uranium inventory to minimize the safety 

and security risks associated with aged 

facilities and invest in upgrades (e.g., the 

LEP) for mid-term capabilities in enduring 

facilities.

Update plan regularly to ensure 

opportunities are taken over the 

lengthy timeline.

Current component manufacturing 

capabilities relying on aging 

equipment and having limited 

capacity to meet future stockpile 

needs.

Execute the extended life plan strategy to 

reduce bottlenecks, improve space 

utilization of existing facilities, and increase 

capacity and reliability of existing processes 

to fulfill near-term mission requirements.

Build and equip a manufacturing 

facility dedicated to EU machining as 

well as material storage to meet 

future stockpile needs.

Current EU facilities experiencing

age-related failures and having

insufficient floor space to support 

future stockpile demand.

Complete the transition to Uranium 

Processing Facility and establish capabilities 

for HEU casting, special oxide production, 

chemical recovery, decontamination, and 

assay.

• Evaluate long-term EU machining 

facility options to meet future 

stockpile demands.

• Sustain existing EU facilities with an

EU LEP strategy to ensure safe and 

secure operations in existing 

facilities until the beneficial 

occupancy of the EU 

Manufacturing Complex Capability. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-12

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Maintaining a trained and qualified 

workforce for EU operations.

• Develop a staffing plan for multi-year 

training. 

• Transfer knowledge from SMEs near 

retirement age to new SMEs.

Implement additional strategies to 

maximize knowledge retention and 

minimize workforce turnover.

Completing modernization strategy 

for all HEU operations.

Implement extended life replacements in 

9215 and 9204-02E. 

Initiate acquisition processes for 

remaining EU replacements, including 

EU Manufacturing Capability and 

Assembly and Disassembly Capability.

EU = enriched uranium

HEU = highly enriched uranium

LEP = life extension program

SMEs = subject matter experts

3.2.2 Depleted Uranium Modernization

DU is a byproduct of the HEU enrichment process and has a lower concentration of the fissile isotope 

uranium-235 and a higher concentration of the fissionable isotope uranium-238 than natural uranium.

High Purity DU (HPDU) and DU Niobium alloy (binary) are required for nuclear component production to 

maintain and modernize the stockpile through life extension, modification, limited life component (LLC) 

exchange programs, and future nuclear weapons. HPDU and binary are made into precision components 

through complex processes that must meet stringent requirements. Key processes include alloying, 

casting, forging, rolling, swaging, forming, machining, assembly, welding, and inspection. Many of these 

processes are currently operable.

The DU Modernization Program is responsible for 

restarting and maintaining lapsed processes to meet 

imminent weapons delivery mission requirements. 

These capabilities lapsed in the early 2000s due to the 

reuse of materials, low demand signals, and 

prioritization of other activities. To resume full-rate 

production, the DU Modernization Program needs to 

execute HPDU and niobium feedstock procurements,

restart and maintain DU and DU alloying and 

manufacturing capabilities, invest in key new 

technologies and execute its bridging strategy to meet 

enterprise demand until 2035, when a new DU 

manufacturing facility is anticipated.

The NNSA has a long-term requirement to reestablish a 

reliable supply of HPDU before the current inventory is exhausted in the 2030 timeframe. To address this 

need, the DU Modernization Program is pursuing the establishment of a capability that converts depleted 

uranium hexafluoride (DUF6) to depleted uranium tetrafluoride (DUF4), which can then be converted to 

HPDU. To mitigate risks associated with the aggressive schedule of this project, the program has been 

working with DoD to determine the viability of recycling DU munitions and invested in procuring DU 

material to supplement existing supplies of HPDU at Y-12.

The DU Modernization Program also supports restarting and maintenance of existing DU operations and 

DU alloying capabilities to meet current and future weapon component needs. To produce new binary, 

Y-12 will restart the alloying process for production of binary ingots. Y-12 has successfully restored the 

Vacuum Induction Melt (VIM) capability and is working to do the same with the Vacuum Arc Melt (VAR). 

Depleted Uranium Modernization 

Accomplishments

• Produced recycled and alloyed binary ingots from 

the Cold Hearth Melter for rolling and forming trials.

• Completed 20 validation castings to achieve 

Technology Readiness Level 7 for the Direct Cast 

technology.

• Executed Analysis of Alternatives activities for the 

DOE Order 413.4B depleted uranium hexafluoride 

(DUF6) to HPDU conversion project to produce a 

reliable supply of HPDU metal feedstock.

• Completed Depleted Uranium Viability Study.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-13

The program will also modernize the wrought manufacturing and machining capabilities needed for 

component manufacturing to increase reliability and capacity. Lastly DU Modernization will train 

operators, develop procedures, and provide DU and binary components for qualification activities at LANL 

and LLNL.

The program is also investing in new technologies to modernize 

production and meet future demands. Direct Casting would 

improve the existing component manufacturing process by 

significantly reducing the risks of current equipment failure, 

decreasing material waste, and improving process efficiency.

Cold Hearth Melting provides an opportunity to alloy ingots 

more efficiently and introduces a material recycling capability 

by alloying certified ingots.

These new technologies could both improve the DU alloying 

process and augment production of DU and binary 

components. As shown in Figure 3–1, the implementation of 

these capabilities provides alternative processes that reduce 

the risk of single-point failure in DU and binary component production. 

Figure 3–1. Potential production process with new technology insertion

The DU Modernization Program must ensure an enduring capability to manufacture DU and binary 

components. Without additional capacity for creating binary feedstock and manufacturing components, 

the existing DU facilities at Y-12 will reach component production limits and will be unable to meet 

component deliveries in support of required weapons modernization programs beginning in 2035 based 

on the demand detailed in the 2022 Production and Planning Directive. The DU mission currently 

performed at Y-12 has capability gaps in aging infrastructure, facility constraints, obsolescence of 

equipment, and capacity constraints. 

The DU Modernization Program is implementing a bridging strategy to increase capacity and reliability to 

meet future enterprise demand. This strategy includes the continued support of planned investments in 

maturing and deploying Direct Casting and Cold Hearth Melting, while addressing the growing NNSAmission related production needs using existing capabilities. Strategic planned investments in the current 

Cold Hearth Melt 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-14

equipment set to increase capacity and reliability, shifts, and load-leveling of 

future mission-related requirements are also being pursued to augment this 

strategy.

Furthermore, the DU Modernization Program will evaluate on and offsite 

solutions to address capacity gaps in the mid-2030s, to include alternative 

acquisition approaches to supplement onsite production. Additionally, the 

program has established a task force to prioritize infrastructure projects across 

Y-12, which will allow the NNSA to focus infrastructure investments on 

capabilities that have nearer term capacity bottlenecks, beyond just the DU 

modernization program.

DU Modernization activities include the following:

1. Supply new HPDU metal feedstock by establishing a DUF6 to HPDU

conversion capability

2. Restart and maintain the VIM-VAR-VAR and component 

manufacturing processes at Y-12

3. Develop, mature, and deploy key new technologies for insertion into production to augment 

existing processes, improve material use efficiency, and reduce reliance on the existing and 

aging processes

4. Modernize existing component manufacturing processes to improve reliability, meet capacity 

and throughput demands, and reduce risk to future life extension programs (LEPs)

5. Execute a bridging strategy to meet weapons deliverables through the Production and Planning 

Directive and increase component capacity with a mixture of modernized existing capabilities 

and new technologies.

3.2.2.1 Status

The DU Modernization Program is currently engaged in many activities to meet imminent weapons 

delivery mission requirements, which include establishing a reliable supply of HPDU by 2030, executing a 

bridging strategy, and restarting and modernizing DU alloying and manufacturing capabilities.

The DU Modernization Program’s goal is to reestablish a reliable supply of HPDU before the current 

inventory is exhausted in 2030. To obtain the large quantities required, the NNSA will need to establish a 

supply chain to convert DUF6 to HPDU. The program completed an Analysis of Alternatives (AoA) to 

identify a solution that addresses the long-term need for HPDU by leveraging existing and potential 

capabilities within the DOE enterprise and through qualified vendors. To augment NNSA’s HPDU supply 

until a long-term capability is established, Y-12 has engaged 

with a vendor to establish a process to convert recycled DU 

oxide from Y-12 and decommissioned DU projectiles from the 

DoD into HPDU.

The DU Modernization program is also restarting DU alloying 

capabilities and maintaining existing manufacturing 

processes. This includes restarting alloying production 

equipment at Y-12, modernizing component and machining 

capabilities, training operators, developing procedures, and 

supporting LANL and LLNL with process qualification 

activities. Collectively, these activities allow for successful 

The Multi-Zone Direct Cast Vacuum Induction Melt

Furnace at the Testing and Demonstration Facility

The Development Vacuum Arc 

Remelt Furnace at the Testing 

and Development Facility
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-15

manufacturing of binary components. Additionally, the program has developed modernization plans for 

the facilities that increase their reliability and capacity by determining which equipment to replace and/or 

update and how to use the available space more efficiently. These plans include schedules for equipment 

removal and installation, floor plans that demonstrate the optimized machine layout for each building, 

and waste management plans for the removal of large equipment.

Along with the wrought and machining capability issues, Y-12’s current alloying process has proven 

reliable but inefficient and leads to significant material waste and excessive costs. DOE/NNSA is 

developing new technologies to replace these aging capabilities and provide a more efficient and costeffective means of producing binary components and allowing DOE/NNSA to meet future production 

demands. The DU Modernization program is accelerating technologies, such as Direct Cast and Cold 

Hearth Melting, by establishing technology readiness teams with stakeholders from production, 

development, design agencies, and technical subject matter experts (SMEs). By including the relevant 

stakeholders in the development and testing phases using high fidelity prototypes, technology transfer 

between development and production is facilitated to insert new technologies into the production 

process. 

DOE/NNSA’s Manhattan Project-era facilities continue to experience age-related failures that present 

significant risk to mission delivery and personnel safety. According to the 2021 Major Asset Plan for Y-12 

facilities associated with DU, those facilities will on average be over 80 years old by 2035. Restarting and 

sustaining DU processing capabilities requires targeted resources to address the risk associated with aging 

equipment and continued training and development of SMEs to produce components and resolve 

technical issues associated with complex processes. Furthermore, these challenges require the 

establishment of the Agile Radiation Case and Component Capability to address the capability gaps caused 

by aging equipment and infrastructure. The Agile Radiation Case and Component Capability will enable 

the DU program to meet increased demand for radiation cases and other DU and binary components,

which will exceed Y-12’s current production capabilities by 2035.

3.2.2.2 Challenges and Strategies

Table 3–4 provides a high-level summary of DU Modernization challenges and the strategies to address 

them. 

Table 3–4. Summary of Depleted Uranium Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

HPDU metal inventory is insufficient 

to meet long-term demands.

• Execute multiple mitigation efforts that

include procuring HPDU from limited 

commercial entities, recycling DU oxide from 

Y-12, and converting DU projectiles into 

HPDU. Invest in cold hearth melting and 

direct casting to increase material use 

efficiency and reduce overall HPDU demand.

• Stand up a long-term HPDU 

conversion capability.

• Bolster the supply chain for 

HPDU and other uranium 

materials by seeking additional 

vendor solutions for conversion 

processes from DUF6 to HPDU.

DOE/NNSA needs to restart, 

modernize, and maintain lapsed DU

alloying capabilities to support 

future stockpile needs.

• Invest in the restart and maintenance of the 

legacy VIM-VAR-VAR alloying processes. 

• Purchase additional equipment to reduce the 

strain on legacy equipment and processes. 

• Coordinate across production and design 

agencies to expedite qualification of binary 

with joint qualification plans. 

• Deploy cold hearth melting 

alloying production technologies 

to improve efficiency and 

recycling capabilities. 

• Integrate direct cast technology 

into production to reduce binary 

material demands and waste 

due to increased efficiencies and 

decrease process risk.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-16

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Current component manufacturing 

capabilities rely on aging equipment 

and have limited capacity to meet 

future stockpile needs.

• Execute the DU bridging strategy to reduce 

bottlenecks, improve space utilization of 

existing facilities, and increase capacity and 

reliability of existing processes to fulfill nearterm mission requirements.

• Purchase wrought critical spare parts to 

sustain the process.

• Invest in direct casting technology to produce 

components more efficiently and reliably.

Establish a DU/Binary 

manufacturing capability to meet 

future stockpile needs. Mature 

new technologies to reduce 

reliance on aging equipment and 

outdated technologies.

Current DU facilities experience agerelated failures and have insufficient 

floor space to support future 

stockpile demand.

• Identify opportunities to meet capacity 

within existing space by co-locating key 

pieces of equipment, improving existing 

processes, upgrading equipment with 

modern controllers, and continuously 

improving strategic material models. 

• Invest to recapitalize the aging physical 

infrastructure, reducing risk to produce 

strategic materials and components.

• Establish a combination of on and off-site 

storage capabilities to store required 

quantities of HPDU feedstock to meet future 

mission demand.

Evaluate long-term DU facility 

options to meet future stockpile 

demands.

Maintain a trained and qualified 

workforce for DU operations.

Develop staffing plan for multi-year training. 

Transfer knowledge from SMEs near retirement 

age to new SMEs.

Implement additional strategies to 

maximize knowledge retention and 

minimize workforce turnover.

DU = depleted uranium

DUF6 = depleted uranium hexafluoride

HPDU = high purity depleted uranium

SMEs = subject matter experts

VIM = Vacuum Induction Melt

VAR = Vacuum Arc Remelt

3.2.3 Lithium Modernization

The Lithium Modernization Program maintains the 

processes that ensure the Nation’s enriched lithium 

materials are supplied to support Defense Programs, DOE’s

Office of Science, the Department of Homeland Security, 

and other customers.

Lithium materials for the nuclear weapons stockpile and 

other customers are currently processed in Y-12’s Building 

9204-2 (a Manhattan Project-era building that has housed 

lithium processing since the 1950s) and in Building 9202. 

The historical processes are very corrosive in nature and have caused accelerated degradation to

Building 9204-02. Additionally, the facility and its processes are oversized for today’s mission, do not 

meet current codes/standards, and are well beyond their designed operational life. The program is 

responsible for the design and construction of a new Lithium Processing Facility that uses improved 

processes.

Until that effort is complete, the Lithium Modernization Program also supports operations for processing 

lithium materials to meet current and near-term mission requirements. Lithium is currently provided via 

a recycling process that relies on retired weapons dismantlement feedstock purified through the wet 

Lithium Modernization Accomplishment

(2022 and 2023)

The team completed the Material Conversion 

Equipment Refurbishment project at Y-12, which 

refurbished and re-started equipment that had 

been idle for nearly a decade. Within a few 

production runs, it is now producing 140 percent 

of program expectation in FY 2023. 
Department of Energy/National Nuclear Security Administration | November 2023

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chemistry process. As part of stockpile surveillance data collection, nondestructive and destructive testing 

is performed on lithium components in full assembly and part forms. 

The program also works with multiple 

DOE/NNSA stakeholders to plan and execute 

recapitalization projects and risk reduction 

activities to sustain the current lithium 

processing capability until the Lithium 

Processing Facility is operational in the 

2030s. Additionally, the program is 

developing the operational release plan for 

startup and transition to full Lithium 

Processing Facility operations. 

The Lithium Modernization Program also 

supports the maturation of technologies and 

development of process improvements that make lithium processing more efficient, safer for workers, 

and less impactful to surrounding infrastructure. In FY 2023, the program continued to expand lithium 

processing expertise to develop future lithium material SMEs across the enterprise, with key partnerships 

at LANL, LLNL, and the Pacific Northwest National Laboratory.

Lithium Modernization activities include the following:

◼ Produce and maintain the lithium material inventory to meet current mission requirements and 

customer deliverables

◼ Purify and convert lithium materials to lithium hydride and/or lithium deuteride, which are the 

two types of lithium materials used for component production

◼ Recapitalize lithium purification and powder production process equipment and perform risk 

reduction activities to sustain process capabilities until the Lithium Processing Facility comes 

online

◼ Develop, mature, and deploy lithium purification and production technologies in support of the 

Lithium Processing Facility baseline and beyond 

DOE/NNSA created a lithium strategy to ensure sufficient lithium processing capabilities (raw materials to 

finished assemblies) are available to meet near- and long-term requirements. The strategy includes:

◼ Sustaining the current Manhattan Project-era infrastructure and equipment until transition to the 

Lithium Processing Facility

◼ Increasing the usable supply of lithium by dismantling and recycling lithium components with 

direct material manufacturing 

◼ Using small-scale technologies to purify and convert lithium

◼ Designing and constructing the Lithium Processing Facility to house lithium processing capabilities 

by 2031

3.2.3.1 Status

A new facility is critical to the long-term strategy for lithium supply. Currently, aging infrastructure and 

antiquated equipment present risks to mission delivery that could affect the ability to meet stockpile 

requirements. The current lithium facility has housed lithium processing for more than 75 years. The 

Current Engineering Design of the Lithium Processing Facility
Department of Energy/National Nuclear Security Administration | November 2023

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historical processes are very corrosive in nature and have 

accelerated degradation of the facility. Structural issues 

due to chemical contamination pose safety and 

environmental concerns, and the facility must be replaced. 

The Lithium Modernization Program will execute 

recapitalization projects and risk reduction activities to 

sustain the current lithium processing capability until the 

Lithium Processing Facility is operational. Modernization 

activities include developing the plan for bridging

operations and transitioning from the existing facility to the 

new Lithium Processing Facility. DOE/NNSA periodically

updates the Lithium Strategy Document and has also 

developed the Lithium Technology Maturation Plan. DOE/NNSA is maturing technologies that will make 

lithium purification and processing safer for workers, more efficient, and less impactful to surrounding 

infrastructure. For example, the next-generation Lithium Electrolytic Cell will improve lithium metal 

processing efficiency and drastically reduce worker hazards by a closed cell design with automated 

processes for remote salt feed and remote metal harvesting. Other technologies being pursued include 

Near Net Shape, Homogenization, Low Temperature Chlorine-Free Lithium Production, and Advanced 

Lithium Purification. Technology Readiness Assessments will be conducted as needed to assess the 

strengths and weaknesses of identified technologies.

DOE/NNSA will continue to work with management and operating partners to develop tailored, long-term 

staffing plans that anticipate critical skills shortfalls within this capability and properly forecast staffing 

levels based on the current program of record. Sustainment of capabilities will necessitate continued 

training and development of SMEs to produce lithium components and resolve technical issues associated 

with complex production processes. 

3.2.3.2 Challenges and Strategies

Table 3–5 provides a high-level summary of Lithium Modernization challenges and the strategies to 

address them. 

Table 3–5. Summary of Lithium Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Insufficient lithium materials. • Restart a small-scale purification capability and legacy 

processing capabilities in the legacy lithium facility to 

provide additional feedstock material. 

• Deploy a production cleaning station to provide 

additional capacity. 

• Complete the Material Conversion Equipment 

Refurbishment project to recapitalize equipment that 

processes salvage solutions, converts lithium chloride to 

lithium metal, and converts the metal to lithium hydride.

• Monitor and optimize weapons dismantlement schedule 

to provide feedstock as needed.

• Construct the modern Lithium Processing Facility on 

schedule to replace infrastructure critical to stockpile 

deliverables at Y-12 by 2031.

• Implement additional 

strategies to increase capacity 

for purification of current Li6 

material not suitable/ eligible 

for Direct Material 

Manufacturing

• Continually monitor supply 

chain risks and opportunities.

Beta-2 Workers Harvest Lithium Metal from 

Electrolytic Cell
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-19

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Sustaining lithium production

in aging facilities until the

transition to the Lithium 

Processing Facility.

• Implement short- to medium-term recapitalization 

investments as appropriate.

• Construct the modern Lithium Processing Facility on 

schedule to replace infrastructure critical to stockpile 

deliverables at Y-12 by 2031. 

• Identify and prioritize future projects to include electrical, 

utility upgrades, and other structural life extending 

efforts.

• Monitor emerging needs and 

implement strategies and 

actions to mitigate risks.

• Implement additional 

strategies to maintain facilities 

past their useful lives.

Delay in transition to 

conducting lithium operations 

in the Lithium Processing 

Facility beyond 2031. 

• Prioritize recapitalization projects, process qualifications, 

and coordination with the Design Agencies to sustain 

current infrastructure to set the conditions for transition 

of operations from legacy facilities to the future Lithium 

Processing Facility.

• Continually monitor integrated schedules to identify 

opportunities for Lithium Processing Facility project 

acceleration.

• Deploy rapid response projects in the legacy lithium 

facility to mitigate aging infrastructure risks and prevent 

interruptions to production. 

• Qualify additional systems for 

Direct Material Manufacturing 

to increase the quantities of 

LiH/LiD available for reuse.

• Identify and prioritize future 

projects to include heating, 

ventilation, and air 

conditioning; electrical; utility 

upgrades; and other identified 

structural life extending 

efforts.

Inability to balance right-sized 

inventories of material with 

ongoing mission priorities and 

manufacturing capacities.

• Optimize small-scale purification capability and legacy 

processing capabilities through lean improvement 

methods.

• Add additional lithium drying capacity.

• Develop and mature strategic lithium process 

technologies (e.g., Homogenization, next-generation 

Lithium Electrolysis Cell) to introduce efficiencies into the 

Lithium Processing Facility. 

• Develop sustainment lithium process technologies (e.g.,

near-net shape forming) to introduce efficiencies into the 

current process and prepare for insertion in existing 

process facilities.

• Optimize design of the frontend wet chemistry process for 

the Lithium Processing Facility.

• Monitor evolving technologies 

and invest in existing or new 

technologies as appropriate.

Maintaining a trained and 

qualified workforce for lithium 

operations.

Develop staffing plan for multi-year training. Transfer 

knowledge from SMEs near retirement age to new SMEs.

Implement additional strategies 

to maximize knowledge 

retention and minimize 

workforce turnover.

Li6 = Lithium 6 (isotope)

LiD = Lithium Deuteride

LiH = Lithium Hydride

SME = subject matter expert

3.3 Tritium Modernization and Domestic Uranium 

Enrichment

Tritium Modernization and Domestic Uranium Enrichment is responsible for producing tritium and 

supplying unobligated low-enriched uranium (LEU) to support national security needs. 

3.3.1 Tritium Modernization

The Tritium Modernization Program maintains and operates the national capability for producing tritium. 

The tritium supply chain’s capacity is increasing as part of a multiyear plan to reliably meet national 

security requirements. Since FY 2003, DOE/NNSA has produced tritium by irradiating tritium-producing 

burnable absorber rods (TPBARs) in the Watts Bar Nuclear Plant Unit 1 (WBN1) and Unit 2 (WBN2) (nuclear 

power reactor) operated by the Tennessee Valley Authority (TVA) during normal 18-month operating 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-20

cycles. The tritium inventory is required to meet national 

security requirements, including support for limited-life 

component exchanges of tritium reservoirs that are 

deployed in the stockpile. The program establishes tritium 

production schedules, which are based on detailed 

computational models and annual tritium reconciliations, to 

maintain required tritium inventories, including reserve 

quantities. Production planning takes into consideration the 

material that is constantly being recovered and recycled 

from deployed reservoirs, including those from weapon 

dismantlements. 

3.3.1.1 Status

Tritium Production

The Tritium Modernization Program must increase capacity 

to confidently meet national security requirements. 

The tritium production goal, independently certified by the 

Nuclear Weapons Council in 2015 as requested by Congress, 

established a requirement to ramp up tritium production 

capacity at TVA by 2025. This production requirement 

necessitated the use of two reactors with 18-month 

operating cycles, as well as an increase to the previously 

established maximum number of TPBARs allowed per 

reactor cycle. WBN1 has produced tritium since 2003 and is 

loading the maximum number of TPBARs currently licensed

by the Nuclear Regulatory Commission (NRC). In 

November 2020, WBN2 began its first-ever 18-month 

tritium production cycle and is expected to reach the established maximum allowable number of TPBARs

by mid-FY 2025. In March 2023, TVA submitted a License Amendment Request to NRC to raise the 

maximum allowable TPBAR numbers by 39 percent per reactor cycle in support of the Tritium 

Modernization Program goals. The Tritium Modernization Program anticipates a 12-month review and 

approval period for the License Amendment Request by NRC. 

To support DOE/NNSA’s long-term tritium needs, TVA plans to prepare 20-year Subsequent License 

Renewal applications for submission to NRC to ensure WBN1 and 2 reactors continue production 

operations through 2055 and 2075, respectively. While DOE/NNSA is confident that the TVA reactors will 

meet or exceed tritium production needs throughout their operating lifetime, the Tritium Modernization 

Program is actively monitoring viable production alternatives, as well as trends in the civilian nuclear 

regulatory environment, to ensure supplies will continue to meet long-term needs. 

As the demand for tritium continues to rise, DOE/NNSA must increase efforts to mitigate risk to 

production plans.

Tritium Processing at SRS

DOE/NNSA operates numerous facilities at SRS that support tritium handling, processing, and storage 

functions, including recovery, nondestructive analysis, and surveillance. In addition, DOE/NNSA is 

implementing a plan to replace or recapitalize aging facilities. This plan focuses on maintenance of 

facilities as well as the need for supply chain management (e.g., vendors, tritium R&D capabilities, etc.).

Tritium Modernization Accomplishments

(2022 and 2023)

• In FY 2022 WBN2 completed irradiation of 

544 TPBARs (Cycle 4) and commenced 

irradiation of 1,104 TPBARs (Cycle 5).

• TVA completed eight shipments of TPBARs 

to SRS in calendar year 2022 (a total of 

2,400 TPBARs), including six shipments 

from November to December. 

• The final design for the thermal cycling 

absorption process column A isotopic 

separation equipment was completed in 

December 2022 in preparation for calendar 

year 2025 installation, in addition to 

awarding long-lead equipment 

procurements.

• CD-2/3 for the Tritium Finishing Facility site 

prep and warehouse subproject was 

completed and approved in December 2022.

• In March 2023, TVA submitted a License 

Amendment Request to NRC to raise the 

maximum allowable TPBAR numbers by 39 

percent per reactor cycle in support of 

Tritium Modernization Program goals. 

• In FY 2023, SRS completed six tritium 

extractions.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-21

After being irradiated, TPBARs are transported to the Tritium Extraction Facility at SRS, where tritium is 

extracted by cutting and heating the TPBARs using unique, specialized equipment. The extracted tritium 

is processed and added to the tritium inventory at SRS. Tritium is used to meet several national security 

needs. One such need is to fill gas transfer system (GTS) reservoirs that meet design agency specifications. 

To recycle tritium from returned GTS reservoirs, or other bulk containers, the gas content is unloaded and 

then processed to remove any impurities. Helium-3, a byproduct resulting from the naturally occurring 

radioactive decay of tritium, is separated from the remaining tritium contents. The recycled tritium gas 

partially replenishes tritium inventory and can be reused in future reservoir fills.

Various tritium extraction and purification processes, along with supporting functions, are performed in 

the H-Area New Manufacturing facility and the Tritium Extraction Facility at SRS. While DOE/NNSA has 

the tritium processing capabilities and capacity to meet foreseeable workload requirements, several of 

the facilities that house these processes were built in the 1990s. DOE/NNSA is currently monitoring the 

health of equipment, infrastructure, waste gas processing, and other facility attributes and is developing 

a plan to maintain and recapitalize the facilities and equipment needed to meet processing requirements 

and other delivery schedules. The plan focuses on both the need to maintain the facilities and the need 

to ensure maintenance of the supply chain, which includes unique equipment, vendors, and tritium R&D 

capabilities. A major part of the plan is the maintenance and repair of aged isotopic separation equipment 

and its supporting infrastructure in the H-Area New Manufacturing facility. This effort (comprising six 

projects) will bring equipment/processes back up to original design capacity and reduce age-related 

maintenance. Long-lead procurement and design activities are currently underway, which will culminate 

in a reservoir loading system partial outage in calendar year 2025. This outage is being closely coordinated 

within DOE/NNSA and with DoD to mitigate impacts to the 

tritium mission and deployed weapons.

The Tritium Finishing Facility (TFF) project, along with several 

minor construction projects, will replace the critical 

capabilities of the existing 65-year-old manufacturing building 

that operates 24/7 for GTS operations. The H-Area Old 

Manufacturing Facility building was designed and built prior 

to modern construction standards and is beyond its expected 

operational service life. The new facilities within the TFF 

Project will adhere to new and more stringent DOE/NNSA 

design and construction standards. For example, the TFF 

design is based on analyses of accidents/impacts from natural 

phenomena, such as earthquakes and high-wind events. TFF

achieved CD-1 in 2019, initiated design activities in 2020, and 

achieved CD-2/3 for the site preparation and warehouse subproject in December 2022. While 30 percent 

Tritium Extraction Facility Personnel Receive 

Irradiated TPBARs Shipped from Watts Bar in 

Preparation for Extracting Tritium for the Nation’s 

Nuclear Deterrent
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-22

design completion was authorized for the overall project, the project is paused from FY 2024–2026 to 

prioritize workforce requirements for the SRPPF project. Funding carried over from FY 2023 will be used to 

complete site preparation work and 30 percent of overall project design, as well as 60 percent of classified 

process design, to better position the project for resumption in FY 2027. The project was scheduled to be 

completed by FY 2031, but will now likely be completed in FY 2034. The existing manufacturing building will 

remain operational, supplying tritium-filled GTS reservoirs to DoD until TFF is operational. Some of the 

facility’s electrical systems have been upgraded to reduce the risk of failure in the short-term until critical 

capabilities can be relocated to new facilities. 

Tritium extraction operations at SRS are keeping up with the growing demand for tritium. DOE/NNSA has 

the workforce capability to meet planned workload and mission deliverables.

3.3.1.2 Challenges and Strategies

Table 3–6 provides a high-level summary of Tritium Modernization Program challenges and the strategies 

to address them.

Table 3–6. Summary of Tritium Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Maintaining a reliable tritium supply 

chain to meet inventory, availability, 

and GTS loading schedule

requirements.

Assess supply chain risks and opportunities. 

Investments are being made that will provide 

a high level of reliability, flexibility, and 

resiliency to the program.

Continue to monitor risks and 

opportunities to identify cost-effective 

solutions and maintain high reliability.

Evaluating alternative tritium 

production technologies or methods 

due to the uncertainties associated

with NRC approval of operating 

license renewal application

submissions in 2055 and 2075 for 

Watts Bar Units 1 and 2, respectively.

• Invest in studies that identify and monitor 

viable and emerging replacement methods 

and technologies as risk mitigation for 

long-term tritium production needs.

• Plan for and invest in reactor vessel 

fluence mitigation strategies to protect 

current production infrastructure and 

improve reactor longevity.

• Monitor evolving technologies and 

invest in existing or new replacement

technologies as appropriate.

• Implement developed core design 

strategies to protect current reactor 

vessels from excess fluence that 

would reduce reactor lifetime 

estimates.

Acquiring replacement limited-life 

facility components and equipment

from foreign sources opposed to the 

Tritium Modernization Program 

mission.

• When appropriate, provide assurances to 

foreign governments that desired 

components/equipment are not in direct 

support of the Tritium Modernization 

Program mission.

• When appropriate and possible, identify 

alternative sources unopposed to the 

Tritium Modernization Program mission.

Develop a supply chain of all critical 

limited-life components and equipment 

that is U.S.-based and sourced.

Maintaining facilities and equipment 

to support stockpile deliverables and 

future Alts, Mods, and LEPs, and 

reduce GTS delivery risks.

Construct the modern Tritium Finishing 

Facility to replace infrastructure critical to 

stockpile deliverables at SRS in approximately 

FY 2034. Continue long-lead procurements 

and other activities needed to support 

replacement of aged tritium isotopic 

equipment and support systems in calendar 

year 2025.

Monitor emerging needs and implement 

strategies and actions to mitigate risks.

Developing technologies that further 

enhance stockpile maintenance,

evaluation, and efficiency of 

processes throughout the tritium 

production lifecycle.

Invest in fundamental tritium science to 

include material property interactions and 

scientific research into the material 

properties and behaviors of TPBARs, GTSs, 

and tritium gas processing technologies.

Develop a strategy to acquire dedicated 

radiological tritium capabilities to 

address future technology needs 

without compromising mission 

schedule.

Alts = alterations

GTS = gas transfer system

LEPs = life extension programs

Mods = modifications

NRC = Nuclear Regulatory Commission

TPBARs = tritium-producing burnable absorber rod
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-23

3.3.2 Domestic Uranium Enrichment

The DUE Program is responsible for ensuring a reliable and 

economic supply of enriched uranium to support U.S. 

national security needs. Since the closure of the Paducah 

Gaseous Diffusion Plant in 2013, the United States has 

lacked the capability to produce enriched uranium free of 

peaceful use obligations (i.e., unobligated). DOE/NNSA 

requires unobligated enriched uranium to fuel reactors 

that produce tritium for nuclear weapons and to power the 

nuclear Navy. The DUE program is implementing a threepronged strategy to meet current enriched uranium needs 

and re-establish an enduring supply of enriched uranium to 

meet long-term needs. First, DOE/NNSA seeks to ensure 

and extend availability of its unobligated LEU fuel supply 

through 2044 by down-blending excess HEU. Second, DUE 

is preserving and advancing uranium enrichment expertise and technology. Third, DUE is executing the 

acquisition process to re-establish a long-term supply of enriched uranium to support future U.S. national 

security needs. 

3.3.2.1 Status

The status of each element of the program are as follows:

◼ Downblend HEU to LEU to extend the tritium fuel need date to 2044. DOE/NNSA has identified 

existing unobligated enriched uranium to power the TVA reactors through 2044. Much of the 

material is HEU “scrap,” which is unattractive for use by other programs. DOE/NNSA is engaged 

in an Interagency Agreement with TVA to manage downblending activities through FY 2025. This 

effort maintains continuous operations at the only commercial downblender, which would 

otherwise close in the absence of feed material. However, because the HEU inventory is finite 

and, at present, irreplaceable, downblending is a temporary solution. 

◼ Develop enrichment technology options. Following an analysis of available enrichment 

technologies, DOE/NNSA determined that centrifuge technologies have the highest technical 

maturity and lowest risk. DOE/NNSA is funding centrifuge R&D efforts at Oak Ridge National 

centrifuge design platform and will continue to 

mature multiple centrifuge designs. In FY 2024, ORNL 

plans to complete a facility extension project to house 

the engineering-scale Demonstration Cascade 2, 

which will evaluate centrifuge enrichment 

performance in a representative cascade 

configuration. 

◼ Execute an acquisition process to deploy an 

enrichment technology. Because of the finite nature 

of the HEU inventory, the United States will 

eventually need a new unobligated uranium enrichment capability. DOE/NNSA approved CD-0 

for this capability in December 2016. DOE/NNSA expects to conclude an AoA and make a final 

technology downselect in the mid-2020s. 

Domestic Uranium Enrichment

Accomplishments (2022 and 2023)

• Oak Ridge National Laboratory (ORNL) 

completed lab-scale cascade testing of the 

first deployable centrifuge design platform as 

part of the Domestic Uranium Enrichment 

Centrifuge Experiment (DUECE) project.

• ORNL broke ground on the facility extension 

to house the engineering-scale 

Demonstration Cascade 2 that will evaluate 

DUECE centrifuge enrichment performance in 

a representative cascade configuration.

Rendering of Demonstration Cascade 2 Facility 

Extension at ORNL
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-24

3.3.2.2 Challenges and Strategies

Table 3–7 provides a high-level summary of Domestic Uranium Enrichment challenges and the strategies 

to address them. 

Table 3–7. Summary of Domestic Uranium Enrichment challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Enrichment technologies are 

complex and difficult to develop and 

deploy.

• Continue to invest in two centrifuge 

technologies to provide optionality and 

contingency. 

• Continue to work with ORNL to increase 

confidence that centrifuge technologies 

are sufficiently matured in time for the 

LEU need date. 

Continue developing centrifuge 

technology options to provide 

additional operational data and 

reduce long-term deployment risks. 

Sources of unobligated LEU are 

finite.

Continuously assess inventory to identify any 

additional unobligated enriched uranium to 

extend the LEU need date. 

Establish a reliable and enduring 

supply of unobligated enriched 

uranium. 

DUE = domestic uranium enrichment

LEU = low-enriched uranium

3.4 Non-Nuclear Capability Modernization

The Non-Nuclear Capability Modernization program 

executes projects to ensure enduring availability of 

non-nuclear component capabilities for all weapon 

systems. The program is responsible for modernization 

efforts related to all non-nuclear components external 

to the primary or secondary stage in the nuclear 

explosive package. Non-nuclear components enable 

critical functionality in the warhead, including arming, 

fuzing, and firing, key safety and use control features, 

and other vital functions. Providing these functions 

requires a wide range of components encompassing 

radiation-hardened microelectronics, neutron 

generators, GTSs, power sources, electrical assemblies 

(e.g., radars, weapon control units, sensors), cable 

assemblies, connectors, mechanisms, structural 

elements, pads/cushions, and a multitude of other 

parts that are incorporated into the systems that 

support or weaponize the nuclear explosive package. 

The Non-Nuclear Capability Modernization program 

modernizes the extensive suite of infrastructure and 

equipment required to support the non-nuclear 

component lifecycle, including design, development, 

qualification, production, and surveillance. 

Non-Nuclear Capability Modernization

Accomplishments

• Polymer Enclave parts production at LLNL

• Established an Electronic Parts Program working 

group that created the funding model for the 

program 

• Power Sources Capability achieved CD-1 at SNL

• Agile Facility build out contract awarded in 

September 2022 with build out completion

expected in the second quarter of FY 2024 at SNL

• Saturn Facility outage preparations completed to 

allow for an effective outage for system upgrades

at SNL

• Pantex production modernization studies awarded 

to include Bays/Cells of the future and Material 

Staging Facility alternative options

• Product Realization Infrastructure for Stockpile 

Modernization (PRISM) project completed the 

combined Mission Need Statement/Program 

Requirements Document at LLNL

• KCNSC’s Strategic Sourcing saved $2.4 million in 

long-term contracting win

• Kansas City Short-Term Expansion Plan

(KC STEP) executed capital equipment

procurements totaling $25 million to support 

production and development
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-25

Non-Nuclear Capability Modernization activities include the following:

◼ Procure equipment to meet non-nuclear component manufacturing capacity requirements

◼ Provide equipment and infrastructure to enable new technology insertion 

◼ Sustain DOE/NNSA’s capability to produce trusted microelectronics

◼ Recapitalize and conduct equipment maintenance on critical environmental test and accelerator 

capabilities that support lifecycle activities (such as components qualification or surveillance) for 

weapon electrical and mechanical systems

◼ Procure equipment that supports the bridging strategy for power sources production capabilities 

◼ Introduce new processes and technologies that increase efficiency in component manufacturing

◼ Mitigate industrial base and supply chain risks for non-nuclear parts

◼ Modernize production capabilities for non-nuclear components through long range planning 

activities and line-item construction projects

3.4.1 Status

KCNSC is the center for non-nuclear component 

production, delivering the majority of 

DOE/NNSA’s non-nuclear components for 

weapon modernization and sustainment.

Completed in 2012 and designed to support 

fewer and less complex weapon modernization 

programs, the KCNSC is challenged to support 

the current program of record. Meeting this 

growing demand involves additional 

equipment procurements to outfit Building 23,

which NNSA purchased in February 2023.

Additional equipment will also be needed to support the future campus being planned. Improved 

collaboration with design agencies using Design for Manufacturing tools will also enhance use of existing 

space by increasing producibility and yield of components. Manufacturing and space needs beyond the 

Future-Years Nuclear Security Program will be addressed thru KCNExT, a multi-year phased campus 

approach that will also allow the exit of leased facilities. Non-Nuclear Capability Modernization will 

validate program requirements and provide capital equipment to fit out the new additional manufacturing 

space provided from KCNExT.

The primary design agency for non-nuclear component research, development, testing, and evaluation is 

SNL. SNL also plays a critical role in the production of non-nuclear components and subsystems. Many of 

the SNL facilities supporting these capabilities 

are beyond life expectancy and critically need 

upgrading and recapitalizing. The primary 

Power Sources facility was originally built as a 

shipping/receiving warehouse in 1949 and then 

converted to manufacturing space. Due to 

severe degradation of this facility, a new facility 

is in design, which will provide a long-term 

solution for the development and production 

of power sources needed for all weapon 

programs. The Power Sources Capability is 

KC STEP Construction Initiated, and Occupancy Contracts Awarded

Rendering of the Power Sources Capability Project

Currently Under Design, SNL
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-26

currently in the preliminary design phase (post CD-1) with an anticipated CD-4 occurring in FY 2030. As 

an interim bridging solution, an agile facility at SNL has been constructed and is being outfitted to 

accommodate a critical portion of the power sources thermal and lithium primary production mission. 

The aging facilities and equipment in SNL’s Microsystems Engineering, Science, and Applications (MESA) 

complex also pose challenges. MESA has an ongoing extended life program to sustain its capabilities 

through at least 2040, and plans are underway to evaluate future capability gaps and develop long-term 

solutions to provide microelectronics when existing facilities are no longer viable.

Aging equipment and capabilities are an issue throughout the enterprise. At SNL, this is impacting major 

testing facilities used to qualify and assess non-nuclear components. These facilities test components in

extreme environments and ensure they meet high reliability requirements. Most of these facilities, 

including the Major Environmental Test Facilities, the Saturn facility, the High-Energy Radiation Megavolt 

Electron Sources III accelerator, and the Annular Core Research Reactor, are decades old and have 

deferred maintenance over the years. Presently, the Saturn facility provides deliverables about 

30 percent of the time due to planned and unplanned maintenance and shot-to-shot irreproducibility,

causing the need to schedule additional tests. The High-Energy Radiation Megavolt Electron Sources can 

only accommodate about 85 percent of requested qualification tests, of which only 75 percent are 

executed due to unplanned outages and data acquisition inadequacies. These facilities must remain 

operational to ensure that non-nuclear components can be qualified as required by the program of record. 

DOE/NNSA is developing a model and methodology to prioritize recapitalization efforts for the 

environmental test facilities.

New Centrifuge Cooling System, Major Environmental 

Test Facilities, SNL

High Speed Camera, Major Environmental 

Test Facilities, SNL

To assist in developing non-nuclear components in a rapid and agile 

environment, LLNL has begun part development at the Polymer 

Enclave, including pads and cushions to support new polymer 

designs and enable an increased pace of technology development 

and deployment with increased production yield. The Polymer 

Enclave is expected to speed the transition from current 

manufacturing and to be used with other technologies in the future.

Leveraging the success of the Polymer Enclave, proposed projects 

such as the Product Realization Infrastructure for Stockpile 

Modernization (PRISM, previously called the next-generation LEP 

R&D facility) are intended to provide increased agility for 

manufacturing responsiveness for other non-nuclear components. 

Other design agency laboratories are also looking into similar or 

complementary facilities to advance early technologies and improve 

manufacturing yield.

Polymer Enclave, LLNL
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-27

3.4.2 Challenges and Strategies

Table 3–8 provides a high-level summary of Non-Nuclear Capability Modernization challenges and the 

strategies to address them. 

Table 3–8. Summary of Non-Nuclear Capability Modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Increased scope and complexity: 

Workload projections to produce nonnuclear components for the program of 

record exceed existing equipment and 

infrastructure capacity. Manufacturing 

space was sized for fewer, less-complex 

weapon systems.

• NNSA purchased Building 23 in February 

2023, which will provide 450,000 square feet 

of manufacturing space through 

modifications referred to as KC STEP. Of 

this new space, 250,000 square feet is 

currently undergoing modifications, 

equipment purchases, and installations. The 

remainder of the building will begin 

modifications in FY 2024. The KC STEP is 

intended to meet the non-nuclear 

component production through FY 2028.

• KCNExT is the long-term initiative to provide 

additional manufacturing and office space to 

meet projected mission requirements. This 

will enable NNSA to terminate current office 

space leases.

Determine the most prudent long-term 

solutions to provide increased 

production capacity at SNL and KCNSC

to meet the Program of Record.

Integration of New Technologies: As 

new manufacturing techniques are 

developed, qualified, and accepted, new 

production capabilities are required to 

support manufacturing methods

involving materials, multi-function 

machines, additive manufacturing, and 

other new approaches. 

Provide relief for critical equipment needs 

related to these key product lines. Investments 

in non-nuclear capabilities enable new 

manufacturing techniques to transition 

smoothly to production by encouraging early 

DA-PA collaborations.

Identify promising technologies that 

may be committed to future 

modernization programs if sufficiently 

mature. These technologies may

enable improvements to stockpile 

safety, use control, and reliability, 

while minimizing the schedule, 

performance, and risk to the 

enterprise.

With integration of new technologies on 

modernization programs (e.g., direct ink 

write polymer cushions and pads), 

KCNSC must maintain capabilities for 

legacy programs consuming significant 

manufacturing space. 

Add additional manufacturing space to support 

select legacy technologies as well as 

development work for modernization programs 

through its KC STEP plan.

DOE/NNSA is in the planning stage to 

add manufacturing space to support 

new and legacy technologies.

Material availability: Some material 

supplies are limited and remaining 

quantities continue to be in high 

demand by modernization programs. 

Continue to use a central material data 

management system to track and monitor atrisk materials and provide a transparent supply 

chain network and associated risks by industry 

experts.

• Continue monitoring supplier 

network risks for non-nuclear 

materials unavailability and provide 

recommended policy actions, 

production options, and material 

mitigation solutions to improve 

supply chain resiliency. 

• Coordinate across DOE/NNSA to 

prioritize material risks, develop 

enterprise-wide mitigation 

strategies, and leverage available 

policy tools.

Limited availability of qualified vendors 

has led to an increase in cost, in-house 

production, and an increased reliance 

on the remaining vendors.

Continue third party market and vendor 

assessments and increased investment into the 

qualification of additional vendors.

Early engagement with design 

requirements to research potential 

new qualified sources. 

DA-PA = design agency-production agency

KC STEP = Kansas City Short-Term Expansion Plan
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-28

3.5 Capabilities-Based Investments

The CBI program manages and executes projects to 

modernize and sustain equipment, tools, supporting 

facilities, and infrastructure. CBI addresses enduring, 

multi-program requirements through discrete, shortduration projects usually lasting from 1 to 3 years. These 

capital investments sustain or replace core nuclear and 

non-nuclear enterprise capabilities for weapons 

assessment, design, production, and certification. Such 

projects include recapitalization of high risk-of-failure 

test, measurement, and production equipment. The CBI 

portfolio reduces programmatic risk to missions across 

the nuclear security enterprise and ensures needed 

capabilities are available for stockpile stewardship, 

sustainment, and modernization, while providing the 

enterprise with increased agility and flexibility to respond 

to emerging requirements and mitigate evolving risks. 

The CBI program funds projects for total replacement of 

equipment or tools, including minor building 

modifications required to install and operate new 

equipment. The projects are predominantly capital 

acquisition projects, requiring CBI to fully fund equipment and installation costs the first year of execution. 

CBI funds activities at all eight NNSA sites, and coordinates closely with production operations, science 

campaigns, other production modernization offices, and additional stakeholders to reduce programmatic 

gaps and align funding sources.

The Programmatic Recapitalization Working Group was established to better understand current and 

future equipment needs across the nuclear security enterprise for all aspects of the nuclear weapons 

mission. This working group includes a combination of participants from the NNSA Office of Defense 

Programs and Office of Infrastructure, as well as full participation from each of the DOE/NNSA sites. The 

Programmatic Recapitalization Working Group helps programs assess equipment risks across the 

enterprise and deconflict planning and programming for activities to address those risks.

Improving experiment capability, Lujan Target Machining parts that support JASPER and U1a 

Complex, High-Torque Mill

Capabilities-Based Investments 

Accomplishments

• Upgraded digitizers for the U1a Complex (U1a)

Z-pinch Experimental Underground System 

Testbed at NNSS.

• Established a new capability to certify the Zeus 

Dense Plasma Focused U1a tritium operations

at NNSS.

• Provided an enclosure for operating highly 

sensitive Coordinate Measuring Machines at

NNSS.

• Replaced the Lujan Target for Los Alamos 

Neutron Science Center at LANL.

• Modernized the Multiplexed Photonic Doppler 

Velocimetry - Gen 4 used at Dual-Axis 

Radiographic Hydrodynamic Test at LANL.

• Established a debonding capability for 

Assembly/Disassembly Operations at Y-12.

• Installed a new 5-axis ultrasonic mill at Y-12.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 3-29

3.5.1 Status

CBI fulfills equipment capability recapitalization needs that do not fit under any specific program. 

DOE/NNSA’s nuclear security enterprise includes numerous laboratory and production capabilities whose 

roles are critical to the success of multiple programs, but whose outputs make up a relatively small portion 

of each program’s activities. Historically, programs prioritized equipment investments on specific, nearand mid-term program of record deliverables. In such cases, risks to multi-program capabilities were 

often overlooked. CBI provides a dedicated program office to address those cross-program risks.

Through the Programmatic Recapitalization Working Group efforts, DOE/NNSA conducts analyses of 

programmatic capital equipment to identify targets of opportunity for investment to reduce mission and 

performance risk. For example, as equipment ages through and past its expected useful life, it may pose 

increased risk of performance degradation and/or failure. Figure 3–2 depicts the useful life status of 

enterprise programmatic capital equipment as of September 2022. The specific pieces of equipment and 

capabilities within the Programmatic Recapitalization Working Group data set also help inform CBI 

investment decisions.

3.5.2 Challenges and Strategies

Table 3–9 provides a high-level summary of CBI challenges and the strategies to address them. 

Table 3–9. Summary of Capabilities-Based Investments challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Limited ability to accurately and precisely 

forecast equipment failure dates for a 

diverse collection of technologies used to 

enable a wide range of capabilities for 

developing, testing, and producing weapon 

systems and subsystems.

Emphasize recapitalization of single 

points of failure, bottlenecks, and 

equipment no longer supported by 

vendor base. Recapitalize before 

equipment begins to fail, to the 

greatest extent possible.

Develop advanced measures of 

effectiveness for equipment 

recapitalization planning to effectively 

capture and analyze data currently 

obscured by relatively long feedback 

loops.

Figure 3–2. Count of equipment by useful life consumed
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Sites have limited internal resources 

available to execute planned projects, 

limiting the amount of equipment 

recapitalization achievable in a single fiscal 

year.

Coordinate work scope that is 

challenging yet achievable based on 

past performance and forecast site 

capabilities.

Continue to grow capacity of key 

resources at NNSA sites, including 

engineering and craft labor.

Unforeseen equipment failures and 

emerging risks.

Maintain flexibility to adapt 

equipment replacement priority list 

by committing to short term projects 

and through frequent updates 

coordinated with other Federal 

program offices.

Evaluate ways to leverage advanced 

machine diagnostics for more 

accurate failure forecasts.
Department of Energy/National Nuclear Security Administration | November 2023

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Chapter 4

Stockpile Research, Technology, and 

Engineering

The Stockpile Research, Technology, and Engineering 

(SRT&E) Program is central to maintaining a credible 

deterrent and ensuring the safety, security, and 

effectiveness of the Nation’s nuclear stockpile. SRT&E is 

responsible for research, development, qualification, 

certification, testing, and evaluation support to stockpile 

sustainment, stockpile modernization, warhead 

production, and the future nuclear security enterprise. 

The program also works to sustain the science, 

technology, and engineering proficiency of the 

Department of Energy’s National Nuclear Security 

Administration (DOE/NNSA) workforce for the future

and helps maintain the readiness of its infrastructure to 

support near-term and future workloads. Innovations 

and development of advanced capabilities in SRT&E are 

key to a resilient and responsive nuclear security 

enterprise.

The drivers for SRT&E include (1) sustaining the deployed 

stockpile; (2) enabling the future nuclear deterrent;

(3) assessing and mitigating threats to the deterrent; and 

(4) developing modern materials, design and 

manufacturing options, and qualification/ certification 

techniques for the nuclear security enterprise. The 

science-based SRT&E Program advances DOE/NNSA’s 

understanding of nuclear weapon functionality through 

science, technology, and engineering research in the 

absence of underground nuclear explosive testing. 

Key activities⎯such as advanced modeling and 

simulation capabilities, subcritical and hydrodynamic 

experiments, high energy density (HED) physics 

experiments, focused experiments, and experiments 

that reproduce the environment U.S. nuclear weapons 

are expected to encounter⎯provide the capabilities to 

support current and future nuclear stockpiles. Enhanced 

experimental and simulation capabilities are required to 

recreate, interrogate, and provide data on materials and 

physics at weapon-like conditions to address these focus 

SRT&E Accomplishments

• Achieved at the National Ignition Facility (NIF) a 

chain-reaction fusion burn in the laboratory that 

generated more energy than was used to drive it.

This is a milestone not only for the NNSA, but for 

the United States and our dedication to the pursuit 

of grand scientific challenges.

• Completed eleven hydrodynamic and static 

experiments at the Dual Axis Radiographic 

Hydrodynamic Test Facility (DARHT) and the 

Contained Firing Facility to support SRT&E 

programs and weapons activities. 

• Bounded changes in plutonium properties with 

age using a combination of data from JASPER, Z, 

diamond anvil cell, and benchtop experiments, 

with supporting modeling and theory work.

• Completed plutonium compressibility experiments 

on the Z and NIF, including shots to evaluate 

changes with manufacturing variations and aging.

• Used capabilities at the NNSA-supported Dynamic 

Compression Sector at the Advanced Photon 

Source at Argonne National Laboratory to 

measure the dynamic response of materials, with 

relevance to manufacturing considerations in 

support of life extension program (LEP) and 

modification (Mod) activities.

• Predicted changes in high-pressure plutonium 

strength with age using large-scale molecular 

dynamics simulations on the Sierra 

supercomputer.

• Developed and delivered a method for rapid 

connector prototyping using advanced 

manufacturing, reducing connector lead times for 

development and Test Engineering applications 

from 6–12 months to 7–14 days at a fraction of the 

cost.

• Completed the Exascale Computing Facility 

Modernization project ahead of schedule and 

under budget, upgrading the Livermore 

Computing Complex to be capable of housing two 

exascale-class systems simultaneously with 85 

MW of power and 28,000 tons of cooling.
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areas. Capabilities developed under SRT&E drive innovation, provide data essential to stockpile 

modernization and production, and help recruit, train, and retain the next generation of the stockpile 

workforce. 

The SRT&E program continues to pioneer, develop, and deploy capabilities to provide DOE/NNSA with 

important, high-fidelity data and capabilities to maintain and modernize the stockpile and associated 

workforce. SRT&E’s world-class capabilities provide a hedge against prospective and unanticipated risks, 

prevent technological surprise, and are critical to enabling technical assessment of the stockpile without

underground nuclear explosive testing.

4.1 Strategic Program Goals

The initial Stockpile Stewardship Program established more than 20 years ago to maintain a safe, secure, 

and reliable nuclear stockpile without underground nuclear explosive testing. The program emphasized 

experimental science and simulation for existing nuclear explosive packages, namely HED science

modeling and simulation (making use of the experimental data), and high-performance computing (HPC) 

(to run the weapon models in the timeframes and detail needed). This approach has been successfully 

applied to the future needs of the nuclear security enterprise in warhead component production and 

timely weapon component design and certification. While the Stockpile Stewardship Program has made 

great advances in nuclear weapon science, experimental capabilities, technology maturation, engineering, 

simulation, and computing, challenges remain and grow with an uncertain geopolitical future, enduring 

and emerging threats, and the aging of the stockpile.

The strategic program goals of SRT&E are still applicable as DOE/NNSA embarks on the next 20 years of 

Stockpile Stewardship. SRT&E continues to address present needs and prepare for the requirements 

associated with an uncertain future. SRT&E advances DOE/NNSA’s understanding of weapon 

performance and demonstrates new component and production technologies as viable options for 

support of the future stockpile. Development of these technologies well before their use in support of 

the stockpile is required to understand the risks that such use would introduce due to aging, changing 

legacy processes, and evolving threats. These technologies enable NNSA to adapt its legacy processes to 

updated workforce and environmental regulations. Moreover, these capabilities add value to the 

program because they:

◼ Drive program plans within SRT&E (Section 4.3).

◼ Align with the 10-year program outlook in the Stewardship Capability Delivery Schedule 

(Section 4.1.1).

◼ Provide requirements for new or recapitalized capabilities that will be realized via the Weapons 

Activities Line-Item Planning (formerly capital acquisition planning) process (Chapter 6, 

Section 6.2.2).

Looking to the future, SRT&E will continue to develop and implement technologiesto address issues facing 

the nuclear security enterprise. As part of an enterprise-wide strategy, SRT&E will take leadership in:

◼ Fostering innovation aimed at improving our understanding of the stockpile and serving as the 

proving grounds for new ideas to meet current and future strategic challenges.

◼ Applying SRT&E capabilities to enable a more modern and efficient production complex.

SRT&E will employ internal and external outreach, communicate the common vision for the future of the 

enterprise more effectively, codify strategies and plans, enable appropriate risk-taking, and foster a 

diverse and skilled workforce. 
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4.1.1 Stewardship Capability Delivery Schedule

The Stewardship Capability Delivery Schedule aligns SRT&E programs with mission objectives, coordinates

efforts across Defense Programs, and serves as a communication framework for internal and external 

stakeholders. DOE/NNSA and the national security laboratories, plants, and sites use the Stewardship 

Capability Delivery Schedule to guide experimental and simulation capability development (Figure 4–1) in 

four key areas:

◼ Stockpile Sustainment guides the efforts that support the needs of the current U.S. nuclear 

stockpile, such as material aging studies and improving warhead system assessment and 

surveillance with experimental, modeling, and simulation capabilities. 

◼ Future Deterrent develops responsive technologies, architectures, and processes designed to 

address emergent threats, increase agility, improve certification processes, and reduce cycle 

times for future weapon development. 

◼ Threat Mitigation develops and matures technologies and experimental capabilities to simulate, 

assess, and mitigate combined and emerging reentry and hostile environments that current and

future weapons may encounter. 

◼ Modern Materials and Manufacturing develops advanced materials and manufacturing of 

materials and components that are robust to full stockpile-to-target sequence (STS) 

environments, extend lifetimes, minimize risk of material obsolescence, improve efficiency, and 

reduce production lifecycle, time, and cost.

Figure 4–1. Stewardship Capability Delivery Schedule – the four key focus areas needed to 

address mission delivery
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4.2 Enduring Drivers for Stockpile Research, Technology, and 

Engineering

Responsible stockpile stewardship demands computational, experimental, and testing capabilities, as well 

as continuous development of a qualified workforce to implement these capabilities. These capabilities 

are essential for stewardship of the current stockpile and must be enhanced to improve understanding of 

nuclear weapons performance to support the effectiveness of our nuclear deterrent into the future. 

Enhancing capabilities to prepare for the future also allows the nuclear security enterprise to remain 

responsive with an ability to adapt to changing geopolitical environments as needed, as well as attract, 

train, and retain the requisite stockpile expertise in the workforce. 

4.2.1 Sustaining and Assessing the Current Stockpile

Understanding the status of the stockpile is essential to planning for its sustainment. The status of the 

current stockpile is monitored through continuous, multi-layered assessments of the safety, security, and

effectiveness of each U.S. nuclear weapon system. As explained in Section 2.1.2.1, the annual stockpile 

assessment process evaluates the safety, performance, and reliability of weapons based on physics and 

engineering analyses, experiments, and computer simulations. Assessments further evaluate the effect 

of aging on performance and quantify performance thresholds, uncertainties, and margins. These 

evaluations depend on all available sources of information, including surveillance, non-nuclear 

hydrodynamic tests, subcritical experiments, HED science, materials evaluation, modeling and simulation, 

and enhanced surveillance techniques. Continuous assessment involves assembling a body of evidence 

to assess performance at the part, component, subsystem, and system levels to determine whether all 

required performance characteristics are met, and relies on new advances in tools, including 

computational and experimental advances. DOE/NNSA uses expert judgment to combine data, theory, 

experiment, and simulation, and arrive at conclusions that are underwritten by extensive peer review. 

SRT&E delivers experimental and modeling tools to evaluate current performance and study uncertainties 

around those baselines. Some of the many sources of information derived from SRT&E activities are 

depicted in Figure 4–2. 

Figure 4–2. Weapon assessments rely on many sources of information from Stockpile Research, 

Technology, and Engineering
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Weapons scientists and engineers are crucial to every aspect of the assessment process. The overall 

assessment philosophy and approach involves quantification of weapon characteristics and a deep 

understanding of the multi-physics mechanisms driving weapons performance under a variety of 

conditions. The laboratory teams responsible for each weapon system and its assessment are comprised 

of scientists and engineers who are deep technical experts in multiple areas relevant to weapons 

assessments and who review historical and new data. Several mechanisms exist to ensure each national 

security laboratory has full and complete access to all relevant weapons data to support these 

assessments. These mechanisms include regular exchanges of electronic documents and databases 

between sites and several peer-to-peer data-sharing options. In addition, DOE/NNSA sites are 

consolidating and digitizing historical weapon data to ensure it is available to future weapon designers. 

The assessments and conclusions in the Annual Assessment Reports are reviewed by independent 

reviewers, federally mandated Red Teams (i.e., subject matter experts from other national security 

laboratories who are appointed by their laboratory directors), program managers, senior laboratory 

management, and the laboratory directors. Specific results related to the stockpile systems are included 

in the latest Report on Stockpile Assessments.

4.2.2 Ensuring the Resiliency of the Future Stockpile

Evolving security environments, as well as the aging of the stockpile, create requirements for LEPs and 

modern replacements for existing stockpile systems. Ensuring the resiliency of the U.S. nuclear deterrent 

requires qualification- and certification-ready options, from materials through components to systems, to 

be matured and available when needed for down-select decisions, development, and production. This 

“readiness for use” demands advances in design, manufacture, qualification, and certification 

methodologies, improvements to the responsiveness of the nuclear security enterprise, improved 

integration with the Department of Defense (DoD), and development of new and emergent capabilities 

for the qualification and certification processes. 

4.2.3 Assessing and Qualifying the Deterrent

SRT&E collaborates with the Stockpile Management Program to steward, advance, and qualify nuclear 

weapons components, subassemblies, and integrated systems to meet the military characteristics across 

the STS environment requirements (e.g., normal, abnormal, and hostile environments specified in the 

STS). These qualification activities are defined in qualification plans and use experimental and 

modeling/simulation capabilities. Experimental capabilities include flight tests, shock and vibration tests, 

thermal environment tests, and exposure to various forms of radiation. Modeling and simulation are used 

to interpolate and extrapolate into regions not addressed by testing and experiments.

4.2.4 Developing Modern Materials and Manufacturing Methods

Thus far, with some notable exceptions, the nuclear security enterprise has continued to rely on legacy 

infrastructure, materials, and manufacturing methods established decades ago that were geared toward 

the mass production of weapons components. Robust manufacturing maturation efforts are key to 

meeting new stockpile and enterprise modernization requirements by developing innovative solutions to 

reduce schedule, cost, and improve weapons components’ reliability over the weapon’s lifecycle. 

Efforts are underway to improve communication and collaboration between the design and production 

agencies with investments in tools that allow the sharing of design data. Flexible architectures that enable 

model-based system engineering approaches should accelerate qualification and certification activities 

and overall lead to the DOE/NNSA being more responsive. 
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As new manufacturing technologies are inserted into the production enterprise, qualification of complex 

components and materials produced will present new challenges. Therefore, the SRT&E Program is 

developing new inspection technologies, such as in-line metrology, which can help detect defects during 

manufacturing earlier in the process and on the same machine, potentially reducing manufacturing times

and accelerating the acceptance process. In addition, new measurement techniques are being developed 

and deployed to more fully characterize products to enable predictive assessments of stockpile 

performance over time.

4.3 Stockpile Research, Technology, and Engineering Elements 

and Status

The five major elements that enable Stockpile Stewardship are the Assessment Science Program, the Inertial 

Confinement Fusion (ICF) Ignition and High Yield Program, the Advanced Simulation and Computing (ASC) 

Program, the Engineering and Integrated Assessments Program, and the Weapon Technology and 

Manufacturing Maturation (WTMM) Program. These elements are illustrated in Figure 4–3. 

Figure 4–3. Subprograms in Science, Research, Technology, and Engineering

4.3.1 Assessment Science

The Assessment Science Program provides the knowledge and expertise needed to maintain confidence 

in the nuclear stockpile in the absence of underground nuclear explosive testing, ensuring weapons will 

perform as required by DoD plans. Capabilities developed and maintained in the Assessment Science 

Program support the entire nuclear security enterprise by providing (1) the scientific knowledge required 

to conduct annual assessments of weapon performance and certification of modernization programs; (2) 

the scientific insight to discern the impacts of surveillance findings to ensure that the nuclear stockpile 
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remains safe, secure, and effective; and (3) the core technical expertise required to respond to technical 

developments and geopolitical drivers. Assessment Science also facilitates the assessment of current 

weapon and weapon component lifetimes, the development and qualification of modern materials and 

manufacturing processes, the exploration of concepts for component reuse, and the development of 

modern safety concepts for sustainment.

Assessment Science performs experiments to obtain the materials and nuclear data required to validate 

and understand the physics of nuclear weapons performance. These experiments include hydrodynamic 

and subcritical experiments to obtain data on the dynamic behavior of plutonium and surrogate materials 

in integral geometries. Science program experiments and data analyses also facilitate evaluation of safety, 

security, and sustainment concepts without the need for additional underground nuclear explosive 

testing. These activities develop, exercise, and strengthen the expertise and competence of the nuclear 

weapon design, engineering, and assessment community. This collection of weapons-relevant data is 

acquired using unique, small- and large-scale experimental facilities throughout the DOE nuclear security 

enterprise. In some cases, Assessment Science also stewards the relevant facilities.

The Assessment Science Program is made up of six subprograms:

Primary Assessment Technologies provides foundational capabilities for annual assessment of stockpile 

primaries, certification of future modernization programs, improvements in primary safety and security, 

and resolution of significant finding investigations (SFIs). It also designs and analyzes subcritical 

experiments that provide essential data to underwrite the performance of the evolving stockpile. This 

subprogram improves predictive ability by developing common models to quantify uncertainties; 

supports experimental platforms to validate weapons physics models; incorporates experimental data to 

improve modeling of boost, plutonium aging, and manufacturing processes; and enables threat-informed 

design and assessment advances.

Dynamic Materials Properties develops and maintains the experimental capabilities needed to describe 

and predict the behavior of weapon materials in extreme environments and ensure weapons perform as 

required by DoD plans. The subprogram provides experimental assessment of special nuclear material 

(SNM), metals, conventional and insensitive high explosives (HE), polymers, and foams under dynamic 

conditions. It furthers understanding of how fundamental material behavior affects nuclear weapon 

performance. The subprogram advances understanding of how plutonium aging and different plutonium 

and HE manufacturing methods impact weapon performance. It also maintains and expands capabilities 

to access pressure, temperature, and strain rate regimes of interest, and advances characterization 

methodologies of these high-interest materials, leading to reduced uncertainties in performance models.

Advanced Diagnostics establishes next-generation tools for delivering stockpile data by developing 

revolutionary diagnostics, novel methodologies, and advanced drivers for future hydrodynamic, 

subcritical, and other dynamic experiments. It matures leading-edge driver technologies that can create 

and diagnose dynamic experimental conditions relevant to the stockpile. It also advances innovative data 

analysis techniques that enhance and expand the results of dynamic experiments.

Secondary Assessment Technologies provides capabilities that assure confidence in the assessment of 

secondaries. This is achieved by using experimental results to validate and improve weapons physics 

models and to evaluate new manufacturing processes, replacement materials, and aged materials in the 

stockpile. This subprogram supports the prioritized development, design, and execution of experiments 

to qualify experimental platforms designed to meet the needs of current and future modernization 

programs, as well as modern investigation of historical underground test data. Through this work, 

Secondary Assessment Technologies provides foundational capabilities for conducting an annual 

assessment of the current stockpile, certifying future modernization programs, and resolving SFIs.
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Hydrodynamic and Subcritical Experiment Execution Support provides the services required to maintain 

a robust integrated weapon testing capability that supplies critical data to weapon physicists and design 

engineers. This subprogram enables execution of prioritized experiments through the National 

Hydrodynamic Test Plan and the National Subcritical Experiments Plan to deliver critical data in support 

of modernization programs, stockpile maintenance, experimental science, and global security. The 

subprogram enables assessments of potential impacts on weapon performance and safety due to design 

changes, material substitutions, or component changes associated with LEPs, alterations, or 

modifications.

Enhanced Capabilities for Subcritical Experiments (ECSE) establishes two new underground test beds 

outfitted with modern diagnostics capabilities that will evaluate the response of plutonium to aging and 

changes in manufacturing techniques, materials, and design. Plutonium data obtained from planned 

subcritical experiments in the ECSE test beds will enable design certification of nuclear systems without 

the need for explosive nuclear testing. For example, ECSE data from will help underwrite certification of 

the W87-1 Modification Program. A major capital investment element of ECSE is the Advanced Sources 

and Detectors “Scorpius” accelerator; the U1a Complex (U1a) Enhancements Project line item is preparing 

the underground U1a to receive this equipment.

4.3.1.1 Status

The Assessment Science Program is executing four major initiatives to advance our understanding of 

weapons physics and improve the capabilities that DOE/NNSA leverages to execute its assessment, 

certification, and qualification missions. The first major initiative is the completion of the Enhanced 

Capabilities for Subcritical Experiments capital acquisition program that will be at the center of 

DOE/NNSA’s modernization programs for the next three decades. This initiative includes investing in the 

workforce and manufacturing needed to support the expected three-fold increase in experimental 

cadence over the coming decade from the traditional, one subcritical experiment per year. The second 

major initiative is the execution of focused experiments that advance the physics and engineering models 

used in weapons simulations. The highest priority of these is the execution of the congressionally

requested Plutonium Aging Plan to inform future assessments of pit lifetimes and eventually enduring pit 

production requirements. The third major initiative is a concentrated effort to execute experiments in 

support of NNSA’s Production Agency. These experiments are required to implement new, more efficient 

manufacturing techniques as part of the nuclear security enterprise’s extensive production modernization 

efforts. The fourth and final initiative is the development of an integrated plan to revitalize our 

experimental science base in accordance with the Enhanced Mission Delivery Initiative report. In 

coordination with data customers, Assessment Science has embarked on a plan for maintenance and 

recapitalization of experimental infrastructure, covering everything from light laboratory and general 

experimental infrastructure to major new science and engineering capabilities and facilities.

4.3.1.2 Challenges and Strategies

Table 4–1 provides a high-level summary of Assessment Science challenges and the strategies to address 

them. 
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Table 4–1. Summary of Assessment Science challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Enable delivery and sustainment

of future weapon systems.

Achieve a robust understanding of weapons’ 

physics, including boost; radiation transport;

hydrodynamics; plasma, nuclear, and material 

properties; and platform and diagnostics 

development supported by a full range of 

experiments. Conduct subcritical experiments to 

inform modernization program decisions, assess 

aging effects, improve safety, provide needed data 

on the hydrodynamics of implosions, and 

underwrite stockpile performance. Understand the 

effects of aging (in particular, aging plutonium) on 

weapon performance through execution of the 10-

year Plutonium Aging Research Program Plan, 

studies on aging, canned subassemblies, and 

evaluations of new materials and processes 

through Production Science partnerships on 

plutonium, uranium, HE, and non-nuclear 

materials. Deliver data on materials properties at 

high-pressure, weapon-relevant regimes to 

understand how the manufacturing process and 

the resulting material structure and properties 

affect performance, safety, reliability, ang aging to 

enable new technologies and appropriate material 

tolerances to increase efficiency of production.

Conduct experiments and analyses 

to resolve principal remaining 

uncertainties, improve predictive 

capability, and expand the 

certification envelope for future 

weapon systems. Enhance 

efficiencies in experimental 

operations to reduce fielding time 

and the number of experiments 

required for assessment and 

certification. Establish domestic 

and global partnerships to leverage 

strategic scientific investments to 

realize capabilities.

Provide capabilities to support 

stockpile assessments, 

modernization options, and 

surety decisions

Deliver world-class experimental capabilities to 

support hydrodynamic testing, dynamic plutonium 

experiments including subcritical experiments, 

nuclear science, materials’ characterization, and 

HED physics.

Invest in a core suite of flexible 

experimental capabilities that 

enable access to weapons-relevant 

environments at a variety of scales,

from small, focused experiments to 

large integrated experiments that 

provide weapon designers with the 

capabilities required to respond to 

a rapidly evolving threat 

environment.

Meet the future stockpile need 

for science-informed analysis 

and evaluation of systems, 

processes, and threats.

Invest in production-oriented R&D test beds to 

accelerate evaluation of cutting-edge technologies 

for the production mission.

Deliver certification-ready options 

for LEPs and the future stockpile to 

inform down-select decisions. 

Enable assessment and certification 

of these options via a sufficient 

range of experiments. Increase 

coordination with other 

Government stakeholders to 

consider how potential new 

technologies would affect strategic 

deterrence.

HE = high explosive

HED = high energy density

LEPs = life extension programs

R&D = research and development
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4.3.2 Engineering and Integrated Assessments

The Engineering and Integrated Assessments Program is responsible for developing modeling, simulation, 

and experimental capabilities to evaluate weapon technologies in present and future STS and ensuring a 

responsive nuclear deterrent through collaborative partnerships, proactive integration, and assessments. 

This program supports four key mission areas: (1) strengthening the science, technology, and engineering 

base by maturing advanced technologies to improve future weapon systems; (2) providing tools for 

qualifying weapon components and certifying weapons without underground nuclear explosive testing; 

(3) supporting annual stockpile assessments through improved weapons surveillance technologies and 

warhead component and materials aging assessments; and (4) providing capabilities that accelerate the 

nuclear weapons acquisition process and strengthen the United States’ ability to respond to unexpected 

developments that could threaten nuclear security.

The Engineering and Integrated Assessments Program is made up of seven subprograms:

Archiving and Support preserves and maintains historic knowledge, records, and data related to U.S.

nuclear weapons testing and Stockpile Stewardship and provides targeted studies, multi-system 

assessments, and independent reviews that support the annual assessment of the stockpile.

Delivery Environments supports experimental and modeling capabilities, diagnostics, and data used to 

evaluate system survivability through normal and abnormal environments in current and future STS.

Weapons Survivability builds the advanced tools, models, and experimental platforms needed to ensure 

U.S. weapons will survive and operate as intended through all hostile environments. 

Studies and Assessments supports pre-Phase 1/6.1 assessments, studies, and other activities; and 

conducts program technical, cost, and feasibility assessments. These assessments inform Nuclear 

Weapons Council decision-makers of the strategic impacts of the pursuit of various nuclear security 

enterprise and weapon capabilities in coordination with U.S. Strategic Command and the Military Services. 

Aging and Lifetimes supports research and development (R&D) to understand and mitigate the impacts 

of aging on materials and components in the stockpile, and develops diagnostics used to assess 

age-induced impacts on weapon systems. 

Stockpile Responsiveness sustains, enhances, and exercises innovative techniques and capabilities 

required to conceptualize, study, design, develop, engineer, certify, produce, and deploy nuclear 

weapons. These efforts do not include the actual production or deployment of a stockpile weapon 

system, nor do they engage in the acquisition of nuclear weapons for the U.S. stockpile.

Advanced Certification and Qualification ensures the feasibility of certification or qualification paths for 

stockpile systems and new components in the absence of additional underground nuclear explosive 

testing. This is achieved by integrating computing, science, technology, and engineering advancements 

to facilitate certification of future life extensions and other warhead needs.

4.3.2.1 Status

The tools, technologies, methods, and data developed within the Engineering and Integrated Assessments 

Program ensure the viability and success of ongoing modernization programs and the rapid certification 

and qualification of future weapon systems. Success depends on diverse, highly qualified staff throughout 

the complex; close coordination and cooperation between weapon designers, weapon engineers and 

production agencies; partnerships with ongoing modernization and surveillance programs; and close 

coordination with the programmatic and technical efforts ongoing throughout the SRT&E portfolio. 
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The program routinely reviews historical records and data to understand how new weapon designs will 

depart from their tested configuration. Without underground nuclear explosive testing, indexing and 

digitizing existing records is an important task to certification. In concert, the program continues to 

expand experimental and diagnostic capabilities to collect data that inform models being developed for 

lifetime predictions and ensure the survivability of weapon systems. 

To ensure the success of new acquisition programs and reduce the associated time and cost, the 

Engineering and Integrated Assessments Program is developing methodologies, computational tools, and 

technology development capabilities to advance the technical readiness and manufacturability of weapon 

systems and components. These include ground and flight-testing capabilities; tools to improve combined 

environment testing; facilities to evaluate hostile radiation exposures; quantification of uncertainties for

engineering models; digital design; engineering and manufacturing tools; embedded sensing; and 

diagnostics. 

4.3.2.2 Challenges and Strategies

Table 4–2 provides a high-level summary of Engineering and Integrated Assessments challenges and the 

strategies to address them. 

Table 4–2. Summary of Engineering and Integrated Assessments challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Ensuring weapon survivability in a 

dynamic worldwide nuclear 

environment

Investing in improvements to sustain current 

radiation environment testing (e.g., ACRR 

sustainment and Saturn refurbishment).

Additional combined environments 

testing and simulation capabilities 

prioritized.

Anticipating the future needs of 

the enterprise

Accelerating technology design and deployment 

process: the Agile Processes and Technologies 

initiative was developed for a rapid clean-sheet 

design to prototype, including DA-PAs working 

together to streamline the development.

Engaging with current advisory panels and DoD

partners

Recurring engagements and 

workshops focused on future need; 

additional emphasis on pre-phase 1 

efforts; and approaches to enhance 

nuclear deterrence.

The highest fidelity aging 

experiments often take years to 

complete.

Providing tools and diagnostics to assess the aging 

and lifetime of the current stockpile, 

understanding age-related phenomena, and 

advancing age-aware models.

Use results of targeted 

experiments to inform bounds and 

validate models.

Invest, implement, and maintain 

multifactor testing and analyses 

rooted in a strong foundation that 

enable optimized accelerated 

aging.

Making the most of legacy data

through digital preservation and 

accessibility of pre-computer era 

nuclear testing data

Rapid digitization laboratories continue to be 

established to process physical media. A 

specialized workforce in filmography, history, 

library sciences, and archiving is being recruited.

AI/ML tools required for metadata 

tagging and database linkage.

Storing and connecting current 

data streams for future use

Build a Knowledge Management framework to 

assure critical knowledge capture, search, and 

retrieval using AI/ML.

Enterprise-wide integration of data 

and resources needed for stockpile 

modernization.

Having flexibility to rapidly adapt to 

changing threat environments

The Stockpile Responsiveness Program explores 

disrupting technologies and processes.

Apply innovative approaches to 

programs of record.

Certification of stockpile warheads

in post-underground nuclear 

explosive testing era

Expand understanding of margins and 

uncertainties; revisit archived information from 

underutilized underground test data; use results 

of AGEX experiments to inform models.

Use AI/ML driven analysis to 

uncover new causal relationships in 

existing test data.

ACRR = Annual Core Research Reactor

AI/ML = Artificial Intelligence/Machine Learning

DA-PA = design agency-production agency

AGEX = above ground experiments
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4.3.3 Inertial Confinement Fusion

The ICF Program studies the effects of the extreme conditions produced inside a detonating nuclear 

weapon. Its twofold mission is to meet immediate and emerging needs for HED data on materials and 

properties under HED conditions to support the present deterrent and to advance the R&D capabilities 

necessary to meet those needs for the deterrent of the future. The ICF Program enables access to and 

data delivery from the HED regime through (1) the design and execution of complex physics experiments 

to improve fundamental and integrated understanding of properties and processes in the HED regime; 

(2) the development of instrumentation to diagnose physics phenomena at the extreme temperature, 

pressure, and density conditions relevant to nuclear weapons performance; and (3) the development,

operation, and sustainment of experimental facilities capable of reaching those conditions.

The ICF Program leverages its experimental design expertise, computational modeling capabilities, 

diagnostic technology, target engineering and fabrication infrastructure, and national HED facilities to 

ensure high-fidelity experimental capabilities and data are available to support a range of DOE/NNSA 

missions. Its capabilities are used by program partners to assess the existing stockpile, inform design 

decisions for current LEPs, investigate hostile nuclear environments, and support DoD research.

The ICF Program supports DOE/NNSA’s long-term R&D mission by developing the knowledge and 

capabilities necessary to reach controlled thermonuclear fusion in the laboratory. Developing a robust

burning plasma1 platform and eventually producing high fusion yield2 opens the door to a range of 

important weapons physics that has been unreachable since the end of underground nuclear explosive

testing, with significant knowledge and capability development at each step along the path from burning 

plasma to ignition and high yield. Not only does the ICF Program attract, train, and challenge some of the 

Nation’s best physicists and engineers, it also represents an important component of DOE/NNSA’s 

preparation to meet the stockpile science challenges of the 2030s and beyond. The ICF Program consists 

of three subprograms.

HED and Ignition Science for Stockpile Applications supports R&D in HED physics and maintains global 

preeminence in HED science by identifying, maturing, and delivering next-generation tools and 

experimental platforms to enable weapons science studies. By supporting data delivery and advanced 

platform development to meet future needs, this area supports nuclear survivability work and 

certification and qualification activities in Assessment Science in partnership with the ASC Program. It 

pursues thermonuclear fusion and eventual high yield to provide access to weapons phenomena and 

energy densities that have been inaccessible since the cessation of underground nuclear explosive testing. 

The subprogram develops expertise and tools for partner programs to experimentally measure dynamic 

material properties; fluid and plasma hydrodynamics, hydrodynamic instability-induced mix, burn, boost;

and radiation transport. It produces unique environments relevant to nuclear weapon outputs and hostile 

radiation conditions. 

1 A burning plasma is one in which most of the plasma heating comes from fusion reactions involving thermal plasma ions. A 

plasma enters what scientists call the burning plasma regime when the self-heating power exceeds any external heating (DOE 

Office of Science website). 

2 High fusion yield is a release of fusion energy in excess of 200 megajoules (MJ) from an ICF target. This is two orders of 

magnitude greater than today’s best performing experiments.
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ICF Diagnostics and Instrumentation establishes new 

diagnostics capabilities and experimental support systems 

for use at the three national HED facilities—NIF, the 

Omega Laser Facility, and the Z pulsed power facility (Z) to 

execute experiments studying matter under extreme HED 

conditions. It develops and deploys transformational 

diagnostics using specialized technologies necessary for

acquiring high-fidelity data during HED experiments. It 

also leverages diagnostic advancements from NIF, 

engineering them to enhance capabilities within the Z 

environment. Diagnostics are often coordinated with 

Assessment Science to meet priority data requirements.

ICF Facility Operations operates and maintains national 

flagship HED facilities and conducts R&D for long-term 

sustainment of facilities and capabilities. Sustainment of NIF and Z is essential to maintain capabilities for 

stockpile assessment, and demand for HED experiments for modernization programs is increasing.

4.3.3.1 Status

ICF remains a critical scientific pursuit of the Stockpile Stewardship Program. In December 2022, the ICF 

Program achieved a historic milestone when a deuterium and tritium-filled capsule ignited at the NIF, 

generating more fusion energy out (3.15 megajoules [MJ]) than laser energy used to drive the experiment 

(2.05 MJ). Secretary of Energy Jennifer M. Granholm hailed this milestone as a “landmark achievement” 

and reaffirmed the Department’s commitment to supporting this world-class scientific effort to both 

combat climate change and maintain the nuclear deterrent without underground nuclear explosive 

testing. Confident in its ability to advance the understanding of the physics of thermonuclear burn, the 

ICF Program has defined goals to accelerate progress toward a robust fusion platform for Stockpile 

Stewardship Program experiments and is investigating the fundamental scientific questions that govern 

the HED processes in ICF capsules and nuclear weapons. These goals also support development of the 

technologies required for future pulsed-power and laser-driven ICF facilities. Such investments are 

necessary to go beyond the recent scientific breakthrough of achieving ignition and realize the goal of 

generating high-yield (200+ MJ) experimental capabilities in the laboratory. A true high-yield platform 

would provide a scientific capability unique in the world and allow the investigation of weapons physics 

regimes that have been out of reach since the end of the underground nuclear explosive testing era, 

realizing the full potential of ICF for nuclear modernization, assessment, and survivability missions.

4.3.3.2 Challenges and Strategies

Table 4–3 provides a high-level summary of ICF challenges and the strategies to address them. 

Sandia National Laboratories’ (SNL) pulsed power 

facility provides experimental data that support 

weapons designers in creating effective models without 

underground nuclear explosive testing
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Table 4–3. Summary of Inertial Confinement Fusion challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Understand the fundamental 

physical phenomena that govern 

the HED processes in ICF capsules 

and nuclear weapons.

Execute experiments targeting key aspects of 

material properties and complex hydrodynamic 

flows in the HED regime using novel diagnostics 

to acquire data that benchmarks our models of 

the interactions between radiation and 

materials. Use HED facilities to provide 

precision data at regimes that were previously 

only accessible by theory or models to enable 

future assessments and certification of device 

performance in the absence of underground 

nuclear explosive tests. Coordinate as 

appropriate with Assessment Science and 

provide timely access to experimental data.

Develop and pursue an integrated 

investment strategy to sustain 

existing HED capabilities and provide 

ongoing and timely access to 

experimental HED needs by the 

program of record.

Accelerate progress toward a 

robust fusion platform for 

Stockpile Stewardship Program 

experiments.

Develop an ignition platform to achieve 

controlled thermonuclear fusion in the 

laboratory that accesses a range of important 

weapons physics phenomena that have been 

unreachable since the end of underground 

nuclear explosive testing to enable new design 

and certification capabilities.

Generate the full range of nuclear 

weapon environments within 

experimental facilities via 

sustainment and development of 

existing Office of Experimental 

Sciences facilities to reach the critical 

portions of the weapons physics 

parameter space, investment in nextgeneration facilities to reach weapons 

physics regimes beyond current 

capabilities, and development of 

novel facility instrumentation and 

advanced diagnostics to measure 

within these regimes with high 

fidelity.

Access energy and density 

regimes required to support work 

on future systems.

Pioneer new experimental platforms, diagnostic 

technologies, and data science and analytical 

tools to meet emerging assessment needs by 

making new and higher fidelity data available in 

HED regimes of interest. Provide intense X-ray 

and neutron sources that can be used to 

support the design and qualification of 

components of U.S. systems in partnership with 

the Assessment Science and ASC Programs to 

meet nuclear survivability requirements.

Develop new driver technologies and 

facility capabilities to provide access 

to energy densities necessary for 

emerging radiation effects and 

assessment science needs. Develop 

HED capabilities to address potential 

changes in STS environments (i.e., 

outputs and effects, thermal and 

mechanical environments), including 

development of experimental 

capabilities required for assessments, 

with increasingly more realistic 

source environments.

ASC = Advanced Simulation and Computing

HED = high energy density

ICF = Inertial Confinement Fusion

STS = stockpile-to-target sequence

4.3.4 Advanced Simulation and Computing

The ASC Program provides high-end simulation capabilities (e.g., modeling codes, computing platforms, 

and supporting infrastructure) to meet the requirements of the Stockpile Stewardship Program. Modeling 

the complexity of nuclear weapons systems is essential to maintaining confidence in the performance of 

our stockpile without underground nuclear explosive testing. The ASC Program develops the weapon 

codes that provide the integrated assessment capability supporting annual assessment and future 

qualification and certification needs for the stockpile. ASC is integral to the execution of the Stewardship 
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Capability Delivery Schedule and provides critical capabilities that help inform decision-making related to 

the sustainment of the nuclear stockpile in support of U.S. national security objectives. The program also 

coordinates within NNSA and with other government agencies, including the intelligence community, to 

support nonproliferation, emergency response, nuclear forensics, adversary capability assessments, and 

attribution activities. 

The ASC simulation capabilities are the key integrating mechanism across the nuclear weapons program 

through the integrated design codes (IDCs), which contain mathematical descriptions of the physical 

processes of nuclear weapons systems and functions. Combined with weapon-specific data, these IDCs 

support high-fidelity, physical models used to carry out design studies, maintenance analyses, annual 

assessment reports, sustainment programs, SFIs, and weapons dismantlement activities, all without 

additional underground nuclear explosive testing. The IDCs currently perform well for general 

mission-related activities. However, issues such as aging, potential new threats, and new manufacturing 

techniques require IDCs with new, enhanced-fidelity physical models that use HPC resources more 

effectively. For the past 28 years, ASC capabilities that support the stockpile stewardship mission were 

built on the relatively stable, commercially available computing technologies and associated programming 

models. To provide increased computing power for both ASC and general consumer markets, the 

computing industry has evolved to more specialized accelerator-based hardware designs that provide 

large potential performance gain. However, that can require codes to be modified or even completely 

rewritten. ASC must stay current with, and continue to influence, the computing industry to ensure 

continued performance of the IDCs on the next-generation compute platforms, as required to maintain a 

credible nuclear deterrent and address potential additional mission needs in non-proliferation, 

emergency response, nuclear forensics, and attribution programs. ASC also develops weapons science 

(single-physics) codes and makes significant use of those codes to underwrite model development and to 

deliver key physical data. Therefore, ASC continues to invest in the portability and improved performance 

of its IDCsto run on next-generation computing platforms. The ASC program consists of five subprograms:

Integrated Codes subprogram produces and maintains large‐scale IDCs that allow the performance of 

detailed nuclear weapons assessments without the need for additional underground nuclear explosive

testing. IDCs and science codes are used for physics and engineering stockpile assessments to support 

concept studies, certification, maintenance analyses, LEPs, alterations, SFIs, and weapons dismantlement 

activities. The IDCs represents a repository of knowledge gained from experiments on DOE/NNSA’s wide 

range of facilities, legacy nuclear explosive tests, and enhancements made to support the Stockpile 

Management Program. These codes enable nuclear forensics, assessments of foreign capabilities, and 

device disablement techniques related to nuclear counter-terrorism efforts and the study of nuclear 

weapons behavior in normal, abnormal, and hostile environments.

The Integrated Codes subprogram also maintains select legacy codes and is responsible for ancillary tools 

that support the weapons mission. These specialized codes enable simulation workflow, generate models 

or information used by the IDCs, and validate the IDCs by comparison with experimental data obtained 

from facilities, such as Z and NIF. In this way, the Integrated Codes subprogram serves as an integrating 

tool for activities across SRT&E.

Physics and Engineering Models subprogram develops and provides the models and databases used in 

simulations supporting the U.S. stockpile. These models and databases describe a wide variety of physical, 

engineering, and manufacturing processes occurring in a nuclear weapon lifecycle, such as equation of 

state (EOS) tables of critical materials such as plutonium, uranium, and various HE formulations. The 

capability to accurately simulate these processes is required for annual assessment; design, qualification, 

and certification of warheads; resolution of SFIs; and development and evaluation of future stockpile 

technologies. The Physics and Engineering Modelssubprogram is closely linked to the Assessment Science 
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Program within the SRT&E, which provides the experimental data that informs development of new 

models used in simulation codes.

Verification and Validation subprogram provides evidence that the models in the codes produce 

mathematically credible answers that reflect physical reality. The verification and validation subprogram

focuses on establishing soundness in integrated simulation capabilities by collecting evidence that the 

numerical methods and simulation models are being solved correctly and establishing that the simulation 

results from mathematical and computational models implemented into the codes are in alignment with 

real-world observations. The verification and validation subprogram funds the critical skills needed to 

systematically measure, document, and demonstrate that the models and codes predict physical 

behavior.

The Verification and Validation subprogram bridges the Integrated Codes and Physics and Engineering 

Models subprograms together with other SRT&E activities to evaluate the capability and accuracy of the 

IDCs. Verification activities demonstrate that the codes and models are correctly solving their respective 

governing equations. Validation activities ensure that both science codes and IDCs are solving the 

equations accurately, and that the models themselves are sufficiently precise for the intended application. 

Together, these subprogram activities provide a technically rigorous, credible, and sensible foundation for 

computational science and engineering calculations by developing, exercising, and implementing tools 

that provide confidence in the simulations of high‐consequence nuclear stockpile problems.

Computational Systems and Software Environment subprogram builds a portfolio of integrated, 

balanced, and scalable computational capabilities to provide the needed computing environment to 

protect DOE/NNSA’s investment in IDCs. In addition to the Commodity Technology and Advanced 

Technology systems that the program fields, the supporting software infrastructure deployed on these 

platforms includes many critical components, ranging from system software to input/output services, 

storage and networking, post-processing (visualization and data analysis tools), and next-generation 

computing technologies. The Computational Systems and Software Environment subprogram also 

examines possible future technologies beyond exascale, such as quantum, neuromorphic, and noncomplementary metal-oxide-semiconductor based computing techniques. 

Facility Operations and User Support subprogram provides and manages the facilities and services 

required to provide nuclear weapons simulation, including physical space, power, cooling, and other utility 

infrastructure; local area/wide area networking for local and remote access; system administration; 

cybersecurity; and operations services. The subprogram also provides computer center hotline and help

desk services, account management, web-based system documentation, system status information tools, 

user training, trouble-ticketing systems, common computing environment, and application analyst 

support.

4.3.4.1 Status

With the conclusion of the ASC Advanced Technology Development and Mitigation (ATDM) subprogram 

at the end of fiscal year (FY) 2023, all next-generation code development, production readiness, user 

engagement, and next generation hardware and software development activities will continue to mature 

within the Integrated Codes and Computational Systems and Software Environment subprograms.

The ASC program is also advancing several internal initiatives, or special projects, to leverage developing 

technologies and capabilities to support the sustainment of the nuclear stockpile. The Large-Scale 

Calculations Initiative was initiated to determine the limitations and scaling potential of our current 

assessment capabilities. It assesses what is achievable with current ASC platforms, codes, and qualified 

personnel, along with what cannot be achieved with those capabilities. “Large-scale calculations,” as 

defined by this initiative, are impractical to perform on available capacity computing platforms due to 
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size, run length, or a combination of the two. The initiative directs the national security laboratories to 

look beyond current computing abilities and ask how calculations on this scale enhance delivery of our 

mission. 

HPC platforms are also evolving in response to the computer industry’s movement toward heterogeneous 

computing, in which accelerators such as graphics processing units, are combined with traditional central 

processing units to increase computing capacity. Recognizing the challenge that this evolution presents 

to use of current IDCs, DOE/NNSA has developed next-generation application codes, which contain new 

capabilities in numerical methods, software technologies, and programming models to optimize the use 

of these emerging HPC technologies. The ASC program continues this work in preparation for DOE/NNSA’s 

first exascale system, El Capitan, to be deployed at Lawrence Livermore National Laboratory (LLNL) by end 

of FY 2024. DOE/NNSA continues to collaborate with the U.S. computer industry to manage the expected 

effects of technological disruptions while continuing to deliver productive compute cycles for Defense 

Programs mission workloads.

In addition to using heterogeneous architectures, the computing industry has evolved new technology 

paradigms that are more energy efficient and has developed artificial intelligence/machine learning 

(AI/ML) capabilities and infrastructure that greatly magnify the capabilities of traditional 

high-performance, physics-based simulation. In response, the ASC program has introduced an Advanced 

Machine Learning Initiative to expand the use of AI/ML capabilities to better manage complexity in 

physics-informed simulations. This initiative will significantly increase efficiency, improve models to 

better match experimental data, and tighten the integration of multi-scale and multi-dimensional models, 

while addressing concerns with validation of these techniques and improving understanding of when new 

errors are introduced. Finally, the ASC Program is driving efficiencies into the manufacturing process 

through the new Production Simulation Initiative. Efforts such as the Simulation First initiative, or 

“SimFirst,” incorporate physics-based simulation into production operations to optimize solutions prior 

to full-scale manufacture. 

As the fidelity of the simulation codes increase, especially those with three-dimensional features, run 

times to reach solution increase dramatically. This presents an increasing challenge in providing timely 

support for mission and experimental needs. To address this challenge, DOE/NNSA continues to follow 

its clearly defined strategy of re-capitalizing its HPC infrastructure at regular intervals; however, evolution 

of these platforms creates increased demand on supporting infrastructure. Power, cooling, and 

mechanical requirements have grown dramatically with the introduction of exascale computing and are 

being addressed through minor construction projects and construction line items. The Exascale 

Computing Facility Modernization project was completed in FY 2022 to upgrade the LLNL HPC facility to 

85 megawatt of power and 2,000 tons of cooling. The nuclear security enterprise will continue to manage 

and coordinate code development and facility upgrades with HPC system acquisitions to provide the 

necessary modeling and simulation services in support of DOE/NNSA stockpile stewardship management 

and production missions.

4.3.4.2 Challenges and Strategies for Advanced Simulation and Computing Program

Table 4–4 provides a high-level summary of ASC challenges and the strategies to address them. 
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Table 4–4. Summary of Advanced Simulation and Computing challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

New physics, engineering, and materials 

applications are needed to support the 

evolving stockpile.

Work with the Stockpile Management, 

Assessment Science, Engineering and 

Integrated Assessments, and Weapons 

Technology and Manufacturing Maturation 

programs to understand the physics of 

these changes, establish requirements, and 

continue to improve modeling.

Higher-fidelity modeling of nuclear 

and non-nuclear components will be 

needed to address interactions in 

new cross-domain environments.

The evolving threat space requires new 

ways for weapons to be certified.

Coordinate through the Nuclear Posture 

Review implementation to understand the 

new needs for threat response and to 

respond with credible simulation 

capabilities.

Modeling of combined threats, 

including those identified in 

coordination with Nuclear Posture 

Review implementation.

Next generation code adoption by the 

Stockpile Modernization and Production

programs and the ability to 

mechanistically simulate the material 

response of weapons effects, aging, and

changes to production and

manufacturing.

Develop and implement a broader range of 

tools for rapid design, evaluation, and 

qualification of new materials. 

Develop models and databases in 

conjunction with experiments to improve 

the performance, reliability, and safety of 

weapons.

Adapt weapon science codes to the most 

advanced computing architectures to reach 

time and spatial scales of greatest interest.

Ensure performance of IDCs and supporting 

codes on increasingly powerful platforms to 

allow quicker time-to-solution for 

applications of simulation enhancements.

Apply agile approaches to code 

development, increasing the rate of 

new capability development.

Engage Defense Programs mission 

programs early and often to fold 

their requirements into design and 

development of new code features.

Place a high priority on code 

usability and user experience.

Performing rapid evaluations of new 

materials and modeling additive 

manufacturing techniques.

Continue current efforts to model additive 

manufacturing processes and couple these 

with molecular dynamics and mesoscale 

modeling to enhance their use.

Develop machine-learned techniques that 

can capture these effects efficiently for 

routine use in part-scale simulations

Develop and mature production 

simulation capabilities with built-in

capabilities to provide quantitative 

risk assessment.

Maintaining current IDC operations to 

deliver on near-term needs, while 

preparing the IDCs for future computing 

architectures

Optimize current codes for advanced 

technology hardware. Develop 

programming model abstractions that allow 

architecture-specific programming to be 

insulated from the code developer

Evolve HPC tools for next-generation

IDCs to achieve sophisticated 

programming models, software 

designs, and numerical algorithms.

Respond to more specialized hardware 

designs from industry to avoid large 

code modifications or mitigate the need 

for wholesale rewrites.

ASC must stay current with, and continue to 

influence, the computing industry to ensure 

continued performance of the IDCs on the 

next-generation compute platforms.

None needed.

More complex facility and infrastructure 

needs (power and cooling) to support

exascale platforms.

Continue to execute the ASC strategy. 

Continually survey HPC vendors’ facility 

requirements, identify gaps, and proceed 

with modernization or new infrastructure 

solutions to meet HPC utility demands.

None needed.

ASC = Advanced Simulation and Computing

HPC = high-performance computing

IDC = integrated design code
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4.3.5 Weapon Technology and Manufacturing Maturation

The WTMM Program is responsible for developing agile, 

affordable, assured, and responsive technologies and capabilities 

for nuclear stockpile sustainment and modernization.

Primary responsibilities of this program include: 

◼ Developing innovative technologies that minimize the 

probability of unauthorized use and meet reliability 

requirements. 

◼ Leading technology and system demonstration efforts, 

with various mission partners, to speed development,

improve acceptance of advanced technologies and 

processes into the stockpile, develop system integration 

technical basis, and reduce risk for future programs of 

record.

◼ Improving agility, effectiveness, safety, and efficiency in 

the design and manufacture of war reserve components 

using advanced technologies and manufacturing 

processes.

The WTMM Program comprises three subprograms, whose 

elements are described below.

Surety Technologies Program is dedicated to simultaneously 

minimizing the probability of unauthorized use and maximizing 

the reliability of authorized use of a U.S. nuclear weapon while 

maintaining the highest levels of safety. Surety Technologies 

creates, develops, and matures advanced safety, security, and 

use-control or denial technologies to minimize the probability of 

an accidental nuclear explosion, and in the unlikely event that security fails and unauthorized access is 

gained, reduces the risk of an unauthorized nuclear yield to the lowest practical level. 

Weapon Technology Development is responsible for developing technology options that are responsive 

to changing global security environments and for activities that reduce risk and increase the likelihood of 

insertion of those technologies into the stockpile. The focus of Weapon Technology Development is to 

improve existing capabilities, provide solutions for addressing capability gaps and shortfalls, evolve 

capabilities to meet emerging threats and changing policy, and use improved technologies and methods

to reduce lifecycle costs. 

Advanced Manufacturing Development designs, develops, demonstrates, and transitions improved 

production processes, including tools, fixtures, parts, and materials designed to ensure the safety, 

security, and performance of the nuclear weapons stockpile. This development enables the nuclear 

security enterprise to respond to emerging issues with the current stockpile and adapt new processes for 

follow-on use, with the objective to provide significant reductions in production time, material waste, and 

floor space. In accomplishing its mission, this program enables DOE/NNSA to meet DoD requirements 

while enhancing safety and security and remaining vigilant and responsive to evolving national security 

requirements.

Direct Ink Write (DIW) silicone pad and 

cushion technology is a polymer Additive 

Manufacturing technique jointly developed 

by LLNL, SNL, and the Kansas City 

National Security Campus (KCNSC). 

DIW is a digital process and is one of the 

advanced manufacturing technologies 

pushing the nuclear security enterprise

into the digital manufacturing realm. 

Technology development has progressed 

from multiple Plant Directed Research 

and Development funded projects at 

KCNSC to the establishment of a highly 

innovative Polymer Production Enclave 

with parallel, nearly identical capabilities 

at LLNL and KCSNC focused on DIW 

technology. The Enclave is expected to 

speed the transition from manufacturing to 

production and the enclave model is 

expected to be used with other 

technologies in the future. The use of 

DIW on modernization programs is a high 

priority at both LLNL and KCNSC 

because the technology enables 

performance that would cost hundreds of 

millions of dollars and could not be 

achieved within the time frame to support 

the programs if attempted with any other 

approach.
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4.3.5.1 Status

WTMM continues to focus on its core areas of work: 

Improved Performance. WTMM seeks to innovate existing capabilities and technologies by improving 

existing performance margins. This ensures stockpile and production technologies can survive long 

lifecycles and continue to be an effective deterrent in emerging threat environments.

Improve Producibility. WTMM engages in innovation of technologies and capabilities that result in 

reduction of production costs. This includes but is not limited to developing technologies that are more 

time and resource efficient to produce technologies that require fewer process steps or less infrastructure 

to produce; and technologies that leverage systems engineering principles for seamless transitions from 

weapon component designers to weapon component manufacturers.

Agile, Assured, and Affordable Technologies. WTMM strives to add flexibility to the stockpile by 

developing and modernizing technologies and processes to be more agile, assured, and responsive to 

change, as well as shortening design qualification, certification, and manufacturing cycles and timelines 

to improve future affordability.

Skilled Technical Workforce and Enhanced Capabilities. WTMM works to maintain a qualified technical 

workforce and enhanced capabilities by transferring knowledge, skills, and direct experience with respect 

to all stockpile technologies and processes.

4.4 Nuclear Test Readiness

The United States continues to observe its 1992 nuclear test moratorium and has not conducted a nuclear 

explosive test in over three decades. While President Biden most recently issued test readiness guidance 

in January 2022, readiness requirements have existed across multiple Administrations and the United 

States has no plans to conduct a nuclear explosive test. DOE/NNSA maintains the readiness to conduct 

an underground nuclear explosive test, if required, to ensure the safety and effectiveness of the Nation’s 

stockpile or if otherwise directed by the President. DOE/NNSA’s evaluation of the response time has 

changed over the years, and the fundamental approach taken to achieve test readiness has also changed. 

Nuclear test readiness covers a broad range of potential activities. Assessments of nuclear test readiness 

require a clearly defined technical basis and well-understood assumptions. Key considerations include:

◼ DOE/NNSA is required to maintain the capability to conduct a nuclear test. National Security 

Memorandum-7 establishes as U.S. policy an expectation that the United States must be ready to 

perform an underground nuclear explosive test using a test article drawn from the existing 

stockpile and limited diagnostics within 36 months, assuming current barriers to achieving this 

timeline in relevant laws and regulations will be overcome. Nuclear test timeline and cost would

depend on the specific details of the test.

◼ Assuring full compliance with domestic regulations, agreements, and laws related to worker and 

public safety and the environment, as well as international treaties, would significantly extend the 

time required to execute a nuclear test. 

◼ DOE/NNSA assumes that a test would be conducted only when the President has declared a 

national emergency or other similar contingency and only after any necessary waiver of applicable 

statutory and regulatory restrictions. 

Since FY 2010, there has been no funding specific to nuclear test readiness as a separate program. 

DOE/NNSA maintains test readiness by exercising capabilities and workforce at the national security 

laboratories and the Nevada National Security Site (NNSS) through the Stockpile Stewardship Program
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and other NNSA programs. Test readiness is a product of a robust, technically challenging science-based 

Stockpile Stewardship Program that exercises essential underground testing elements at NNSS, such as 

mining, as well as investments in the personnel and infrastructure of the nuclear security enterprise. 

Operations such as subcritical experiments at the U1a are exercising some of the possible workforce, 

physical assets, and infrastructure required for an underground nuclear explosive test. These experiments

involve critical skills and formality of operations, including design, preparation, and fielding of advanced 

diagnostics; modern safety analysis; experimental execution; and recovery and analysis of the data. 

Subcritical experiments also exercise critical skills and concept of operations with respect to weapon 

design.

DOE/NNSA continues to leverage subcritical experiments for test readiness, as such experiments are 

challenging, multi-disciplinary efforts that enhance the technical competency of the nuclear security 

enterprise workforce. DOE/NNSA also leverages experiments on HED physics platforms such as NIF, Z, 

and the Omega Laser Facility to preserve the capability for maintaining relevant measurement 

capabilities, such as prompt measurement of optical, X-ray, gamma-ray, and neutron flux from 

experiments with next-generation technologies similar to underground nuclear explosive test 

measurements. The Stockpile Responsiveness Program also contributes to ensuring the readiness of the 

workforce.

Some of the capabilities and technologies used during testing continue to be updated or replaced. 

Migrating to newer technologies entails maintaining legacy capabilities while assessing options that 

adhere to the foundational data of previous tests. The test readiness strategy is to reconstitute 

underground nuclear explosive testing elements if or when needed, rather than maintaining obsolete 

facilities and capabilities. DOE/NNSA assesses that the current nuclear test readiness complies with 

current Presidential directives and public law.
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Chapter 5

Security

This chapter covers several aspects of security within the Department of Energy’s National Nuclear 

Security Administration (DOE/NNSA): The Secure Transportation Asset (STA) program, the Defense 

Nuclear Security (DNS) program, and the Information Technology (IT) and Cybersecurity program. 

Together, these programs provide the safe and secure transportation of nuclear weapon assets; security 

of the Nation’s nuclear materials, physical infrastructure, and workforce; and security of information 

assets at DOE/NNSA Headquarters and its field offices, national security laboratories, nuclear weapons 

production facilities, and the Nevada National Security Site (NNSS). 

5.1 Secure Transportation Asset

The STA provides safe, secure transport of the Nation’s 

nuclear weapons, weapon components, and special 

nuclear material (SNM) throughout the nuclear security 

enterprise to support DOE/NNSA missions. Nuclear 

weapon warhead modernization, limited life component 

(LLC) exchanges, surveillance, dismantlement, 

nonproliferation activities, and experimental programs rely 

on STA’s safe and secure transport. 

The fiscal year (FY) 2024 President’s Budget Request 

supports modernizing and sustaining STA transportation 

assets, including life extension of the Safeguards

Transporter (SGT) until it is replaced by the Mobile 

Guardian Transporter (MGT); vehicle sustainment; 

replacement armored tractors, escort vehicles, and support 

vehicles; upgrades of the Tractor Control Unit to 

accommodate for communications and security: and 

continued development and testing of the MGT. The MGT 

will replace the current SGT through a phased in approach. Program Direction resources in this account 

provide salaries and expenses for the secure transportation workforce.

While STA’s highest priority is Weapons Activities missions, it also provides secure transport for other 

DOE/NNSA programs and offices, such as NNSA’s Nuclear Counterterrorism and Incident Response 

Program, NNSA’s Office of Naval Reactors, and DOE’s Office of Nuclear Energy, as well as the Department 

of Defense (DoD) and other U.S. Government agencies. STA is U.S. Government-owned and operated 

because of the control and coordination required and the potential security consequences of material loss 

or compromise.

Secure Transportation Asset 

Accomplishments

• Completed approximately 150 safe and 

secure deliveries in fiscal year (FY) 2022.

• Completed Test Article 2 (TA2) Over-theRoad Testing, delivered the Pre-Production 

Unit Rolling Chassis, and completed the 

Qualification Door Assembly in support of the 

Mobile Guardian Transporter.

• Completed 3 Nuclear Material Courier Basic 

training courses graduating 36 new Federal 

Agents.

• Executed vehicle sustainment efforts to 

ensure mission vehicles are upgraded and 

maintained to provide reliable mission 

support.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-2

5.1.1 Status

STA has continued its record of 100 percent safe and secure 

shipments without compromise, loss of components, or release of 

radioactive material. This record is enabled by the core 

components of the STA security concept of specialized vehicles, 

secure trailers, specially trained Federal Agents (FAs), and 

leading-edge communication systems. To maintain its exemplary 

record, STA must continue to modernize the transportation assets 

and communication systems for convoy safety and security, and 

recruit and retain the FA and program staff workforce to meet 

mission capacity and customer requirements. These efforts are 

described below. STA must maintain assets to sustain convoy safety 

and security to support missions based on changing customer needs, and current and future threats. 

These assets include vehicles (trailers, armored tractors, escort vehicles, and support vehicles), aircraft, 

and a highly trained FA workforce. The process of identifying, designing, procuring, and manufacturing 

vehicles takes several years. The SGT fleet vehicles reached the end of the projected design lifecycle in 

2018. STA has implemented a standard 4-year maintenance, risk mitigation, and refurbishment program 

to extend the life of the SGT until replaced by the MGT. The MGT will assure weapon-related cargo and 

containers, safety, and security; protect the public; and meet nuclear explosive safety standards. 

In FY 2021, STA procured its first Boeing 737-700 aircraft replacement which was delivered in FY 2023 to 

begin mission operations. 

5.1.1.1 Vehicles

Modernizing and sustaining STA’s vehicle assets requires an integrated 

strategic plan and a substantial investment for lifecycle replacement. 

The STA strategy includes steady-state initiatives such as eliminating 

outdated vehicles, refurbishing operational vehicles to extend their 

useful life, and procuring new vehicles.

The process of identifying, designing, procuring, and manufacturing 

these vehicles takes several years. The current armored tractor and 

escort vehicle are being replaced by the Next Generation Armored 

Tractor (T4) and Escort Vehicle (EV4). STA continues to assess and 

refurbish vehicles to extend lifecycles until replacements are available. 

Evaluating demands on vehicles is a continuous effort to keep pace with operational requirements.

5.1.1.2 Trailers

The trailer fleet is a critical asset for transporting nuclear cargo on 

public highways. The design, engineering, testing, production, 

and use of these trailers can span several decades. The design 

and construction features address public safety, unique cargo 

configurations, and protection systems. The SGT fleet began 

reaching its end-of-design lifecycle in FY 2018, years before the 

first MGT will enter production. STA has implemented an 

aggressive SGT maintenance, risk reduction, and refurbishment 

program to ensure safe and secure transport. The maintenance 

Escort Vehicle

Mobile Guardian Transporter – Test Article

Nuclear Material Courier Basic 

Graduates
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-3

program ensures the trailers remain operational, while the risk reduction will help prevent issues such as 

components becoming obsolete. 

The MGT program has been delayed due to staffing challenges and supply chain disruptions that emerged 

during the Coronavirus Disease 2019 pandemic. The delay has impacted the first production unit delivery 

schedule; however, efficiencies and strategies are being implemented to help mitigate further adverse 

program impacts. In FY 2022, MGT completed Test Article 2 (TA2) Over-the-Road Testing and site visits, 

Pre-Production Unit delivery, and the Qualification Assembly. Planned milestones for FY 2023 include 

completion of TA2 Stage Assembly Build, TA2 Testbed Integration Testing, and Thermal Testing, and 

Initiation of Active Delay System Energetics Production. Major planned activities for FY 2024 include TA2 

Head-On Crash Test, completion of the Pre-Production Unit Assembly, and Qualification Post Crash 

Testing. The photo below shows the completed MGT Pre-Production Unit Rolling Chassis prepped for the 

first road trip. 

5.1.1.3 Aviation

The fleet of U.S. Government-owned aircraft provides for the efficient and flexible airlift of LLCs, nuclear 

incident response elements, FAs, joint test assemblies, training assemblies, and personnel and equipment 

associated with national emergencies and disasters. STA is required to maintain an aircraft on continuous 

alert with a rapid response time to nuclear incidents. STA must also support evacuation and relocation of 

key personnel to maintain the continuity of U.S. Government operations. 

STA aircraft support the NNSA Nuclear Emergency Support 

Team, which includes the Joint Technical Operations Team, the 

Accident Response Group, and the Radiological Assistance 

Program. STA procured a Boeing 737-700 aircraft in FY 2021 

(shown) that replaced a 1969 DC-9 aircraft and was delivered in 

FY 2023. STA’s current fleet of two Boeing 737-400 aircraft are 

over 30 years old and are planned for lifecycle replacement in 

FY 2027 and FY 2032, respectively. 

5.1.1.4 Communications

Reliable, secure, real-time communication is crucial to STA mission success. Essential communications 

include information that is obtained, analyzed, and disseminated for mission planning; continuous 

monitoring and updating of that information during mission execution; and continuous communication 

Replacement Aircraft (Boeing 737-700)

Mobile Guardian Transporter – side view Mobile Guardian Transporter – rear view
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-4

during convoy operations. These various tiers of communication must be executed seamlessly in real 

time, while balancing the evolving need for cybersecurity to ensure system reliability and integrity. STA 

is continually evaluating risk, researching emergent technologies, and implementing new tools and 

practices, such as incorporating new vehicle communications, (Global Positioning System and Trailer 

Status Interfaces), including Radio Frequency Identification in fixed-site communications, and ensuring 

Exercise Command and Control support.

5.1.1.5 Workforce 

STA is committed to strategies to recruit and retain people with the requisite skills to meet priorities and 

mission requirements, and considers the many years it takes to achieve growth in the FA workforce due 

to the extensive hiring process, security clearances, and attrition. STA is encountering many of the 

workforce challenges described in Chapter 7 and is implementing initiatives to attract, hire, and maintain 

the FA workforce. 

Once hired, FAs receive cutting edge training, accredited by 

the Federal Law Enforcement Training Center, in full-scale 

emergency and tactical operational scenarios, tactical driving 

techniques, and a variety of weapons and explosives. Each FA 

Command has facilities and staff to refresh primary skills and 

accomplish qualification training. The Training Command in 

Arkansas supports basic to advanced training, including special 

weapons, tactical scenarios, and other general training 

covering all aspects of convoy operations, as well as an initial 

Nuclear Material Courier Basic training program for FA 

candidates. The Federal Law Enforcement Training Center in Georgia provides a follow-on course for FAs, 

emphasizing legal authorities and law enforcement concepts. FA law enforcement authority and 

specialized training are continually evaluated to respond to the dynamic operational environment. STA 

continues to recruit and retain the FA workforce to meet mission capacity and customer requirements. 

5.1.1.6 Safety and Security

Validation Force-on-Force exercises are assessments designed to test STA’s Active Security Doctrine and 

determine system effectiveness for the STA’s Site Security Plan. The vulnerability assessment team 

designs, performs, evaluates, and documents the conduct of these assessments; the training and logistical 

staff support the Validation Force-on-Force exercises and integrate them with the emergency command 

and control elements to provide the most realistic convoy scenarios possible. STA also executes safety 

studies and safety engineering for the safety basis, nuclear explosive safety, and over-the-road safety 

issues. The Site Security Plan and the Documented Safety Analysis outline compliance with security and 

safety orders and regulations as related to nuclear operations within DOE/NNSA.

5.1.1.7 Liaison

STA maintains a liaison program with agencies and organizations that may be in contact with a convoy or 

must respond to an STA emergency. This interface extends across the United States, with a focus on 

primary and secondary convoy routes. The scope of the liaison function includes Federal, state, Tribal, 

and local agencies and involves interactions with law enforcement officers, firefighters, emergency and 

hazardous materials responders, dispatchers, and military personnel. 

Federal Agent Training
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-5

5.1.2 Challenges and Strategies

Table 5–1 provides a high-level summary of Secure Transportation Asset challenges and the strategies to 

address them.

Table 5–1. Summary of Secure Transportation Asset challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

The SGT fleet is beyond its design life and 

sustaining it involves challenges such as 

unavailable or obsolete parts, difficulty 

finding new manufacturers, the high cost of 

limited-run production, and meeting Nuclear 

Explosive Safety Study requirements. 

Support SGT risk-reduction program 

and continue design and production 

activities toward development of the 

MGT. Work with partners to identify 

mitigation strategies, address Nuclear 

Safety Study requirements, and sustain 

the required readiness posture of the 

STA fleet. 

Evaluate, update, and replace STA 

assets as required to meet mission. 

Incorporate MGT into mission 

operations as fleet becomes 

available.

STA is facing FA staffing challenges. 

Feedback and analysis have shown that pay 

is not competitive with other organizations, 

it takes too long to be promoted, and there 

is a lack of financial assistance to move to 

duty locations. 

Continue to implement initiatives to 

attract, hire, and maintain FA end 

strength. Initiatives include increasing 

starting pay for incoming FAs, offering 

recruitment incentives, and creating 

ladder positions for FAs.

Evaluate and monitor results from 

STA hiring initiatives (to support 

increases FA end strength and 

decreases in attrition).

Delayed schedule to MGT first production 

unit have resulted due to supply chain 

disruptions which are impacting deliverables

(emanating from supply chain issues for

materials/piece parts and a loss of critical 

skills within the vendor workforce bases). 

Custom electronic printed wiring 

board/printed wiring assembly fabrication 

needed to support MGT have been 

especially impacted.

Allowing for longer lead times and 

making parallel purchases from 

multiple vendors to reduce schedule 

risk has had some success. Alternate 

parts to address shortages have been 

identified to circumvent fabrication 

delays but often require design 

modifications. 

Strengthen the U.S. industry base of 

suppliers in custom electronics 

design.

FA = Federal Agent

MGT = Mobile Guardian Transporter

SGT = Safeguards Transporter

STA = Secure Transportation Asset
Department of Energy/National Nuclear Security Administration | November 2023

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5.2 Defense Nuclear Security

DNS leads, develops, and implements the 

security program to enable DOE/NNSA’s 

nuclear security enterprise missions. DNS 

provides protection for DOE/NNSA personnel, 

facilities, and nuclear weapons and materials 

from a full spectrum of threats, ranging from

minor security incidents to acts of terrorism, 

across all the sites of the nuclear security 

enterprise. In addition, DNS provides nuclear 

security expertise for a broad set of 21st century 

national security needs, such as those in 

defense nuclear nonproliferation, homeland 

security, and intelligence, in line with its core 

mission. Employing more than 1,700 Protective 

Force officers, DNS secures SNM, classified 

materials, and more than 6,000 buildings in 

addition to protecting more than 57,000 

personnel at its national laboratories, 

production plants, processing facilities, and 

NNSS. DNS also provides personnel security 

clearance processing and adjudication for the 

nuclear security enterprise. The major 

elements of the DNS program are illustrated in 

Figure 5–1.

Dedicated and specially trained security 

professionals address general and site-specific 

threats and carry out the physical security 

mission at each field location. DNS comprises 

Safeguards and Security elements that provide 

the day-to-day secure environment necessary 

to execute DOE/NNSA’s national security 

mission. DNS also provides facility clearances 

for contractor organizations that perform 

classified and unclassified work; processes 

personnel security clearance actions for 

DOE/NNSA; and administers the classification 

program to ensure information is properly identified for appropriate handling and protection. Table 5–2

provides a brief description of each DNS program element. 

Defense Nuclear Security Accomplishments

• Completed operational capability of counter uncrewed 

aircraft systems (CUAS) for operations:

- 2018 – Los Alamos National Laboratory

- 2022 – Nevada National Security Site

- Q2-2023 – Pantex Plant

• FY 2022: Successfully implemented Trusted Workforce 1.5. 

This included submitting over 30,000 fingerprint requests 

and enrolling over 90 percent of DOE clearance holders into 

the Record of Arrest and Prosecution Back system, which 

supports near real-time evaluation of clearance holders.

• FY 2022: Granted over 6,000 new security clearances in 

support of mission growth across the NNSA nuclear security 

enterprise.

• FY 2022: Initiated efforts to streamline security approvals for 

medically necessary personal electronic devices used in 

security areas.

• FY 2022: Started construction on first Security Infrastructure 

Revitalization Program (SIRP) project at the Y-12 National

Security Complex (Y-12).

• FY 2023: Achieved full operating capability of the Portable 

Intrusion Detection System, a rapidly deployable detection 

system/compensatory measure developed in partnership 

with DoD.

• FY 2023: Collaborated with the DoD Office of Nuclear 

Matters to improve threat assessments, technology 

development, policy, and other areas of mutual benefit.

• FY 2023: Implemented Local Area Nuclear Material 

Accountability System software enhancements at all user 

sites. This enables accurate material accounting.

• FY 2023: Co-led the Enduring Organizational Improvement 

Initiative for the Risk Management sub-group of the 

Governance and Management effort to identify safety and 

security requirements that could be retired permanently or 

modified to improve efficiency without increasing risk.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-7

Figure 5–1. Defense Nuclear Security Program elements (excludes construction)

Table 5–2. Defense Nuclear Security Program elements

DNS Element Description

Protective Force Protective Force officers are an integral part of a site’s security posture and are trained in 

tactics and techniques necessary to protect DOE/NNSA sites. These forces are each site’s 

primary front-line protection and consist of armed and unarmed uniformed officers. 

Physical Security Systems Physical Security Systems oversees counter uncrewed aircraft systems, intrusion detection 

and assessment systems, performance testing and certification/recertification, access 

control systems, barrier and delay mechanisms, canine explosive detection programs, and 

tactical systems. This element includes the Security Infrastructure Revitalization Program.

Information Security Information Security provides classification guidance, technical surveillance 

countermeasures, operations security, classified matter protection and control, and 

administration of special access programs.

Personnel Security Personnel Security includes access authorizations, badging, portions of the Human 

Reliability Program, classified and unclassified visits, and foreign national assignments. It 

encompasses administrative support for the site clearance process, including security 

clearance determinations at each site.

Nuclear Material Control and 

Accountability

Nuclear Material Control and Accountability controls and accounts for special and 

alternate nuclear materials through measurements, quality assurance, accounting, 

containment, surveillance, and physical inventory. Management of the Local Area Nuclear 

Material Accountability System, or LANMAS application, as well as training and 

operational support, is provided to DOE/NNSA sites and facilities.

Security Program Operations and 

Planning

Security Program Operations and Planning manages development of budgets; responses 

to audits and information requests; reviews of Site Security Plans, security planning, and 

assessments (including vulnerability/risk assessments); and performance testing and 

assurance. It also includes security incident and reporting management, security surveys 

and self-assessments, activities related to deviation requests, and control of security 

technology transfer activities. Lastly, it supports facility clearance processing and foreign 

ownership, control, or influence determinations for security contracts.
Department of Energy/National Nuclear Security Administration | November 2023

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5.2.1 Status

5.2.1.1 Counter Uncrewed Aircraft System

DNS is focused on addressing the threat posed by uncrewed aircraft systems (UAS) and the need for 

effective countermeasures, which is among DOE/NNSA’s top security priorities. The first DOE/NNSA CUAS 

platform was deployed at Los Alamos National Laboratory in 2018. NNSS and the Pantex Plant achieved 

full operational capability in 2022 and mid-2023, respectively. DNS participates in the CUAS National 

Action Plan Interim Planning Committee and continues to work closely with departmental security 

counterparts and interagency partners, including DoD, the Department of Homeland Security, the Federal 

Aviation Administration, the Department of Justice, and appropriate congressional stakeholders to 

maintain an effective CUAS capability. 

5.2.1.2 Security Infrastructure Revitalization Program 

The Security Infrastructure Revitalization Program (SIRP) is a multi-year program designed to addresses 

critical security systems and related security infrastructure across DOE/NNSA, focusing on revitalizing 

aging security infrastructure by providing Physical Security Systems upgrades and lifecycle management 

across the nuclear security enterprise through General Plant Project. SIRP project requirements were 

derived from the data obtained during a detailed condition assessment completed at each DOE/NNSA 

facility. The condition assessment identified the oldest systems and systems with the highest risk for 

failure and assessed these systems’ contributions to the overall security posture. DNS recently began 

work on the Quadrant 1 Perimeter Intrusion Detection and Assessment System refresh and completed 

the Post 8 Booth Replacement SIRP projects at Y-12. 

5.2.1.3 Departmental Collaboration

DNS participates in the Capital Acquisition process, the Integrated Planning Group, the Management 

Council, the Chief Security Officer Committee, and the Insider Threat Steering Committee to maintain 

close collaboration with other NNSA and DOE entities. DNS recently revitalized collaboration with the 

United Kingdom’s Ministry of Defence and its Atomic Weapons Establishment, as well as DoD, to identify 

opportunities for partnership on respective nuclear security programs. This effort focuses on 

opportunities to identify and implement improvements in how the two agencies harmonize their 

respective nuclear security programs, including threat assessments, technology development, policy, and 

other areas of mutual benefit.

5.2.1.4 Personnel Security

DNS successfully implemented Trusted Workforce 1.5, which included submitting over 30,000 fingerprint 

requests and enrolling over 90 percent of DOE clearance holders into the Rap Back system. In addition, 

the web-based Clearance Action Tracking System was recently upgraded to track and manage Trusted 

Workforce changes. This system was also adopted by DOE as the adjudication system of record for 

clearance activities and provides Trusted Workforce workload intake, case management, and adjudicative 

support. 

5.2.2 Sustainment Investments

DNS has a process in place for funding operations and sustainment of Safeguards and Security 

infrastructure, equipment, and facilities. During the annual programming process, management and 

operating (M&O) partners submit requests for funding these requirements, which include upgrades to, 

and replacement of, security infrastructure, security systems, equipment, and facilities. This routine 

Planning, Programming, Budgeting, and Evaluation process, accomplished in close coordination with 

NNSA’s Office of Management and Budget, is essential to the protection of DOE/NNSA’s critical missions. 
Department of Energy/National Nuclear Security Administration | November 2023

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5.2.3 Challenges and Strategies

A continuing challenge for DOE/NNSA, and the U.S. Government overall, is identifying and addressing new 

and emerging security threats. Each threat is assessed and prioritized according to national security 

importance, taking into consideration the effectiveness of existing security measures. Through tactical and 

strategic planning and collaboration with counterparts, DOE/NNSA remains focused on addressing these 

security challenges. Table 5–3 provides a high-level summary of various DNS challenges and the strategies 

developed to address them.

Table 5–3. Summary of Defense Nuclear Security Program challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Increasing presence of CUAS DOE/NNSA currently employs three fully 

operational CUAS platforms and will achieve 

full operational capability in FY 2023 at the 

remaining planned Category I sites. In 

addition, DOE/NNSA continues to engage 

with other government agencies on the CUAS 

threat and furthering CUAS technologies.

DNS plans to leverage future technologies 

and next-generation efforts to continue 

addressing emerging threats.

Modernizing aging security 

systems and infrastructure, 

while leveraging new technology

DOE/NNSA is in the final stages of 

development and initial stages of 

deployment for Caerus, a modern security 

system that will replace Argus, which has 

been in use for over 25 years. Caerus is a 

modernized and upgraded version of an 

integrated system that can incorporate 

commercial off-the-shelf technologies while 

possessing improved cybersecurity. 

In addition, NNSA continues to prioritize 

security infrastructure recapitalization efforts 

through the SIRP and WEPAR project.

Partner with various 

organizations/agencies to assess and 

deploy future technologies designed to 

enhance the overall effectiveness of inplace security measures, aid in the 

development of enhanced cybersecurity, 

and incorporate the use of artificial 

intelligence.

Addressing Insider Threat DOE/NNSA has implemented a robust 

process that includes continuous vetting as 

part of Trusted Workforce, screening 

technologies to deter and detect insiders, 

and insider vulnerability interviews of 

employees and contractor partners designed 

and conducted by the site vulnerability 

assessment analysts and the Local Insider 

Threat Working Groups. In addition, steps 

taken to identify and mitigate insider threats 

include utilizing the DOE Employee Concerns 

Program website to report potential insider 

threats, continuous evaluation conducted by 

supervisors and cybersecurity personnel, 

security and law enforcement reporting, and 

administrative reporting on employees who 

are members of the Human Reliability 

Program. 

Collaborate with DOE partners to 

strengthen the current insider threat 

mitigation techniques, establish a 

DOE/NNSA-managed Insider Threat 

Program, and identify opportunities to 

address the increased insider threat 

resulting from the advancement of 

technology and popularity of social media. 

CUAS = Counter Uncrewed Aircraft System

DNS = Defense Nuclear Security

SIRP = Security Infrastructure Revitalization Program

WEPAR = West End Protected Area Reduction project
Department of Energy/National Nuclear Security Administration | November 2023

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DOE/NNSA began analyzing new and emerging threats, including weaponized UAS, in the Design Basis 

Threat Change 1 Order. By late 2023, all DOE/NNSA Category I site CUAS platforms will have full 

operational capability. These systems currently provide DOE/NNSA with a capability to counter UAS; 

however, the increasing sophistication of UAS will require frequent updates and additional investments 

to continue to address the threat. DNS is exploring options to transition to a more adaptable approach 

necessary to detect, track, identify, and deny current and future technologies from threatening the 

security enterprise.

The continuation of increased weapons requirements has led to mission growth across the nuclear 

security enterprise, especially in the areas of weapon modernization and infrastructure investment and 

recapitalization. This mission growth drives increased security program resource requirements across 

every security discipline. For example, increases in site staffing necessitate additional personnel clearance 

action, and increases in square footage require additional personnel and physical security infrastructure; 

Protected Force support; classified matter protection and control; technical surveillance 

countermeasures; classification program support; and programmatic management. Figure 5–2 illustrates 

these requirements.

Figure 5–2. Infrastructure and Weapons Program expansion

5.3 Information Technology and Cybersecurity

DOE/NNSA’s Office of the Associate Administrator for Information Management and Chief Information 

Officer (NNSA OCIO) is the organization responsible for Federal information management and IT and 

complex-wide cybersecurity for DOE/NNSA. The NNSA OCIO is a mission partner that enables DOE/NNSA 

to accomplish its strategic goals and objectives through the delivery of secure, agile, and risk-informed IT 

and cybersecurity solutions.
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NNSA OCIO accomplishes its mission by improving network connectivity and resilience, maturing 

DOE/NNSA’s cybersecurity posture, and providing and directing cybersecurity across DOE/NNSA 

enterprise and to its mission partners. This office manages the IT portfolio, Federal IT investments, 

services, and projects in alignment with DOE/NNSA and departmental strategies, as well as other national 

policy drivers. Services are provided through three offices: Cybersecurity, Mission Integration, and IT. 

These offices work in tandem to:

◼ Increase organizational efficiency and effectiveness

◼ Protect classified and unclassified information assets

◼ Enhance communication with internal and external partners

◼ Provide continuous monitoring and support effective incident response

◼ Ensure information is protected from unauthorized access and malicious acts

◼ Comply with statutory requirements governing classified data protections and information 

assurance 

5.3.1 Transformations to Ensure Information Security and 

Cybersecurity Throughout the Nuclear Security Enterprise

Digital Transformation

In FY 2022, the NNSA OCIO embarked on a digital transformation effort that: 

◼ Improved, upgraded, and enhanced the mission unclassified and classified logical infrastructure

◼ Enabled Artificial Intelligence and Machine Learning

◼ Performed IT and application modernization

The goal of the transformation was to implement sufficient management, operational, technical 

operation, and safeguards throughout the nuclear security enterprise to maintain adequate protection of 

information and information assets. 

Enterprise Transformation

DOE/NNSA continues to implement an enterprise transformation initiative that will deliver a modern, 

reliable, comprehensive, secure computing environment that supports the enterprise and aligns with 

current and future IT service delivery models. With the managed services model, DOE/NNSA’s networks 

will benefit from industry best practices and receive ongoing patching and monitoring. They will 

incorporate hardened configurations from a security perspective, fine-tuned settings for performance, 

and dynamic configurations to meet evolving business environments. 

5.3.2 Information Technology and Cybersecurity Program Elements 

and Initiatives

The IT and Cybersecurity Program focuses on the development of integrated IT initiatives that provide an 

effective technology infrastructure and support to the DOE/NNSA nuclear security enterprise shared 

services. These initiatives will fundamentally redesign the IT and cybersecurity environments to provide 

a more secure and responsive set of capabilities, including unified communication, agile cloud 

infrastructure, and next-generation collaboration services across the nuclear security enterprise. The 

major elements and initiatives of the IT and Cybersecurity Program, supported by Mission Integration, are 

illustrated in Figure 5–3. Table 5–4 provides a brief description of each of these program elements.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 5-12

Figure 5–3. Information Technology and Cybersecurity major elements and initiatives

Table 5–4. Elements of the Information Technology and Cybersecurity Program

NA-IM Element Description

IT Modernization An enterprise transformation initiative that will grow cloud services over time and 

deliver a modern, well-managed, secure computing environment that will eliminate 

many of the inefficiencies and performance degradations currently experienced by the 

workforce.

Logical Infrastructure To improve and enhance the classified infrastructure for its Enterprise Secure Network.

Application Modernization To perform application rationalization for mission IT applications. This evaluation of 

applications will be used to determine the best method of migration for current 

applications onto the modernized classified network.

OT Assurance A methodology to secure the operational technology used in nuclear weapons 

production, testing, and facility control capabilities across the enterprise.

Enterprise Secure Network Increases the capability, capacity, and responsiveness of the DOE classified 

infrastructure in direct support of DOE/NNSA missions and the statutory requirements 

governing classified data protections and information assurance.

RD Working collaboratively with other Government agencies (such as DoD and the FBI) to 

identify interagency needs and opportunities for accessing, sharing, and leveraging RD.

FITARA OMB Memorandum M-15-14, Management and Oversight of Federal Information 

Technology. The NNSA FITARA Implementation Framework, approved in September 

2019, provides details on how NNSA will implement the Act in accordance with the 

OMB memorandum.

Mission Integration Oversight 

Support

To provide oversight support to core IT and cybersecurity operations and achieve 

organizational, strategic, and mission goals.

Collaboration Efforts with DOE 

Partners

Physical Security Systems – The application of technology to improve physical security.

Integrated Joint Cybersecurity Coordination Center – Provides 24/7 situational 

awareness of evolving cybersecurity threats, operational status, and associated risks to 

DOE mission essential functions.

TEMPEST Management – To evaluate and mitigate technical risks to systems in support 

of its risk management oversight and control authorities.

FBI = Federal Bureau of Investigation

FITARA = Federal IT Acquisition Reform Act

IT = information technology

OMB = Office of Management and Budget

OT = operational technology

RD = Restricted Data
Department of Energy/National Nuclear Security Administration | November 2023

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5.3.3 Ongoing NNSA OCIO Activities

NNSA OCIO continues to manage IT and cybersecurity projects designed to help reduce risks. While these 

efforts are projectized, they are not managed under the same acquisition policies as the line-item 

construction or minor construction projects.

5.3.4 Planned NNSA OCIO Activities

Figure 5–4 are the recent and ongoing accomplishments for NNSA OCIO and the office anticipates 

completing the following activities in FY 2023:

◼ Pilot classified mobility solutions

◼ Expand the Center of Excellence for threat intelligence beyond DOE/NNSA

◼ Execute the acquisition strategy to provide additional IT mission and cybersecurity support to 

critical classified and unclassified systems

◼ Complete the development of the next level of operational technology (OT) classes in 

collaboration with the Office of Defense Programs

◼ Complete deployment of multifactor authentication and encryption for national security systems 

data-at-rest and data-in-transit

◼ Support field office IT services provisioned by M&O and oversee the M&O unclassified IT 

programs

◼ Implement the application modernization project and enterprise Voice over Internet Protocol as 

a service

◼ Provide oversight of activities related to, and ensure agency compliance with, the provisions of 

the Federal IT Acquisition Reform Act (FITARA)

◼ Enable IT operations and maintenance of the critical infrastructures and networks

◼ Cybersecurity improvements identified in Executive Order 14018, Improving the Nation’s 

Cybersecurity Infrastructure

◼ Address specific findings from the Institute for Defense Analyses (IDA) Cybersecurity Assessment:

– DOE/NNSA contracted with the IDA, a Federally Funded Research and Development Center, 

to conduct the assessment.

– The cybersecurity assessment was completed in the spring of 2022.
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Figure 5–4. Ongoing and recently completed information technology and cybersecurity projects

5.3.5 Status

5.3.5.1 Significant Changes Since the Last Stockpile Stewardship and Management Plan

The NNSA OCIO continues to make enhancements to the Enterprise Secure Network infrastructure, and 

is implementing additional IT modernization, with an emphasis on addressing risks related to software 

assurance, operational OT assurance, and supply chain management. The IT and Cybersecurity Program 

continues to support working from home and extensive videoconferencing, including classified 

videoconferencing for a large portion of the workforce.

5.3.5.2 The Current and Future Anticipated Mission Requirements

Due to the increased demand for advanced technology to protect information, agility is critical to respond 

to cybersecurity threats and technology requirements.
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5.3.5.3 Current State of the Infrastructure

The NNSA OCIO is currently securing unclassified and classified networks in place that adequately support 

nuclear security enterprise needs, but require constant evaluation and ongoing upgrades against changing 

threats.

5.3.5.4 Current State of the Workforce

There are continuing challenges recruiting and retaining top talent due to competition for IT and 

cybersecurity resources. NNSA OCIO will continue its efforts to meet current and future workforce needs 

by analyzing job requirements to meet the mission’s evolving needs. By doing so, NNSA OCIO will continue 

to be a competitive employer that can recruit, develop, and retain top talent in the IT and cybersecurity 

workforce. 

5.3.5.5 Technologies Deployed to Address Cybersecurity Threats

NNSA’s IT and Cybersecurity program maintains management, operations, and technical security 

safeguards throughout the nuclear security enterprise for adequate protection of information assets. The 

workforce that develops, deploys, and uses the security tools listed in Table 5–5 to provide the first lines 

of defense against known adversaries and emerging threats. 

Table 5–5. Technologies deployed or to be deployed to address Information Technology and 

Cybersecurity threats

Cybersecurity Framework 

Core Function Technology

Identify

Enterprise Governance, Risk, and Compliance

Center of Excellence Sensor Platform for Cybersecurity Intelligence 

Vulnerabilities Asset Management

Supply Chain Management Center Solution

Protect

Multifactor Authentication Identity and Access Control Management Solution

Encryption

Firewalls

Intrusion Prevention System

Detect

Network Monitoring

Configuration Management

Respond

Incident Response

Enterprise Forensics

Recover The nuclear security enterprise maintains overlapping cybersecurity technology capabilities 

that ensure defense-in-depth and continuity of operations at alternate locations.

5.3.6 Challenges and Strategies

The highly complex and global nature of DOE/NNSA and its nuclear security enterprise, coupled with 

limited resources, makes it critically important that information and information assets are secured, 

managed, and protected using a risk-management approach. As the cybersecurity threat landscape 

constantly evolves, it is critical for NNSA OCIO to keep up and adapt to the ever-changing IT, OT, and 

cybersecurity defenses and to respond rapidly to the evolving and sophisticated threats. Table 5–6

provides a high-level summary of IT and cybersecurity challenges and the strategies developed to address 

them.
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Table 5–6. Summary of Information Technology and Cybersecurity challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Ensure purchased equipment is from 

the manufacturer, as designed, and 

without modification.

Move toward centralized purchasing and 

equipment review before issuing equipment 

to the field will address current supply chain 

and software assurance issues. This will align 

to OMB Memo 22-18: Enhancing the Security 

of the Software Supply Chain through Secure 

Software Development Practices.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.

Insider Threat Continue to work with counterintelligence on 

an insider threat program.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed

Network Aging Infrastructure/IT 

Support

• Improve network infrastructure by updating 

and enhancing networking equipment 

through public/private cloud services, 

managed services, software, and hardware 

enhancements.

• Mature capabilities of aging infrastructures 

enterprise-wide to identify and alert 

concerning emerging threats.

• Ensure faster capabilities development and 

implementation to counter such threats.

Threat analysis will determine 

future strategies. 

Identify, inventory, and ensure proper 

cybersecurity hygiene is applied to OT 

• Collaborate early with program managers, 

operations, and engineering teams to plan 

for IT and cybersecurity requirements 

during the planning stage.

• For legacy OT and Industrial Control 

systems, perform analysis to identify and 

inventory systems, devices, and all assets.

• Ensure applicable cybersecurity hygiene is 

applied to OT and industrial control 

systems.

Threat analysis will determine 

future strategies.

Current network monitoring services 

restrictions

• Upgrade sites across the enterprise through 

deploying new cybersecurity solutions.

• Ensure all networks, IT, and OT systems are 

monitored 

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.

Not all buildings support network 

speeds are fast enough for today’s 

scientific computing, and with 

technology’s reliance on computers, 

capacities are being exceeded across 

the nuclear security enterprise.

Continued investment is needed in network 

communications systems and in the central 

networking and telecommunications facilities.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.

Program effects from 2022 Nuclear 

Posture Review Implementation

• Ensure IT and cybersecurity capabilities 

keep pace with increases in weapons 

program workloads.

• Ensure a secure, protected, and innovative 

work environment.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.

Fill critical cybersecurity and IT 

vacancies across the enterprise.

Bolster cybersecurity and IT workforce as 

recommended in the IDA cybersecurity 

assessment report.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Fulfill OMB guidance to consider and 

use cloud solutions in a secure 

manner.

Modernize current services by capitalizing on 

cloud technology to increase performance and 

strengthen security.

Threat analysis will determine 

future strategies. However, 

ongoing threat analysis will 

determine whether further 

strategies are needed.

Fully adopt cybersecurity 

improvements identified in Executive 

Order 14028 (Improving the Nations 

Cybersecurity Infrastructure).

• Conduct baseline inventory and state of 

existing threats, risks, and mitigations 

associated with current enterprise IT 

systems.

• Work with IT and program offices to 

implement a strategy to migrate to zero 

trust across environments.

Threat analysis will determine 

future strategies.

Accommodate current and future 

teleworking needs across the NNSA 

complex.

• Continue to develop and implement 

services and solutions to increase 

teleworking security and ease of use, while 

transitioning focus to recruiting retention.

Apply future technology to ensure 

services and solutions are available 

to enhance operational 

connectivity and transition focus to 

recruiting retention. 

Artificial Intelligence/Machine Learning 

(AI/ML)

• Develop an AI/ML strategy.

• Improve supply chain security processes 

using business intelligence.

• Unlock the power of data to make riskbased decisions.

• Set policy for artificial intelligence and 

machine learning for the enterprise.

• Seek technical applications to meet 

business/mission requirements.

The current strategy is sufficient. 

However, ongoing threat analysis 

will determine whether further 

strategies are needed.

IDA = Institute for Defense Analyses

IT = information technology

OMB = Office of Management and Budget

OT = operational technology
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Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 6-1

Chapter 6

Infrastructure and Operations

Infrastructure modernization is essential to the Department 

of Energy’s National Nuclear Security Administration’s 

(DOE/NNSA) mission to ensure a safe, secure, and effective 

stockpile, reduce mission risk, and improve employee, 

public, and environmental safety. Demand on the existing 

infrastructure is increasing due to multiple concurrent 

stockpile modernization programs and the need to advance 

science, technology, and engineering activities at 

DOE/NNSA’s laboratories, plants, and sites. These factors 

present many complex challenges, particularly given 

DOE/NNSA’s aging infrastructure. In light of these 

challenges, DOE/NNSA, with congressional support, has 

increased the resources allocated to and made significant 

progress in modernizing its infrastructure, eliminating 

excess facilities, and improving management practices.

Figure 6–1 illustrates the size, age, and scope of 

DOE/NNSA’s nuclear security enterprise infrastructure that 

drives the challenges and strategies discussed in this 

chapter. Comprehensive enterprise asset management 

requires continuous, multi-level planning across the entire 

spectrum of asset types, resulting in balanced enterprise 

investment decision-making across the entire asset 

management lifecycle, as shown in Figure 6–2. Planning 

initiates an asset’s lifecycle, followed by acquisition through 

new construction, lease, or purchase. 

The majority of an asset’s life is spent in continuous 

sustainment through maintenance, repairs, and 

replacements-in-kind, with periodic recapitalizations to 

upgrade and extend the asset’s service life prior to 

disposition. These lifecycle asset management activities are 

presented in the rest of this chapter.

Chapter 6 begins with a set of high-level, enterprise-wide 

challenges to lay the foundation for subsequent discussions. More specific challenges are contained in 

the discussions for each subsection, as appropriate. The asset management lifecycle model shown in 

Figure 6–2 is used to frame the discussion for different types of investments across a variety of funding 

sources and sponsoring programs. Sections 6.2 through 6.6 each reflect the activities within each element 

of the model. Infrastructure planning and asset management, described in Section 6.2, estimates future 

repair of and modernization investments in facilities as they age, forecasting facility replacement 

schedules, planning for new and replacement acquisitions, and anticipating the disposition needs and 

Infrastructure and Operations Major 

Accomplishments

• The Standardized Acquisition and 

Recapitalization Initiative (STAR), which uses

a standard design to reduce costs and 

accelerate construction of small office and 

light laboratory facilities across the nuclear 

complex, has been the basis for 17 projects, 

with four completed in fiscal year (FY) 2023. 

• Three Emergency Operations Centers at 

Lawrence Livermore National Laboratory 

(LLNL), Y-12 National Security Complex 

(Y-12), and Sandia National Laboratories

(SNL), as well as a Fire Station at Y-12, were 

all executed within the pilot program for 

Enhanced Minor Construction and 

Commercial Practices (EMC2) under budget 

and ahead of schedule.

• In April 2022, NNSA completed construction 

on the John A. Gordon Albuquerque 

Complex, a modern, energy efficient, 333,000 

square foot building that provides workspace 

for over 1,200 NNSA employees and 

contractors along with great common areas.

• In March 2023, DOE/NNSA purchased 

Building 23 to support the Kansas City 

National Security Campus (KCNSC) mission. 

This facility will help KCNSC meet mission 

demands and be more strategic with 

manufacturing space to accommodate nearterm facility needs while supporting long-term 

manufacturing requirements.
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costs of excess facilities for completion in a timely manner. Sections 6.3 through 6.5 describe the different 

acquisition strategies and funding approaches necessary to build long-term infrastructure modernization 

programs, and Section 6.6 addresses the disposition of excess facilities. Programmatic equipment, when 

acquired independently of other infrastructure projects, is discussed in Section 6.7, rounding out the 

discussion of the Weapons Activities capability element that consists of facilities, infrastructure, and 

equipment.1 Section 6.8 discusses how the DOE/NNSA programs outside the direct nuclear weapons 

mission areas benefit from Weapons Activities investments for their own national security mission needs. 

Section 6.9 concludes the chapter with a discussion on management and performance.

Within Sections 6.2 through 6.6, the various funding strategies and acquisition approaches provide the 

organizing framework for discussion. The wide range of programs, processes and funding types discussed 

are testament to the complexity of aligning investment needs to funding sources. The funding strategy 

to support any given type of project can vary greatly due to the project’s size, scope, and other factors. 

Facility acquisition occurs through line-item projects, minor construction, purchase, or leasing. Operating, 

maintaining, and revitalizing existing facilities are funded through Recapitalization, Maintenance, and 

other programs. 

Figure 6–1. DOE/NNSA infrastructure size and scope

1 The Weapons Activities capability elements were discussed in detail in Chapter 3 of the Fiscal Year 2023 Stockpile Stewardship 

and Management Plan (FY 2023 SSMP).
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Figure 6–2. Asset management lifecycle

In addition to modernizing DOE/NNSA’s physical infrastructure, continuous investments are required to 

sustain and modernize critical physical security and cybersecurity elements across the nuclear security 

enterprise. Specific construction and recapitalization activities related to security are included in 

Sections 6.3 and 6.4. Additional physical security and information technology/cybersecurity activities are 

described in Chapter 5, Security. 

6.1 Challenges and Strategies

To enable the nuclear deterrent mission, DOE/NNSA develops and implements infrastructure 

modernization strategies to meet significant challenges:

◼ The need to address the poor, but improving, conditions of DOE/NNSA facilities

◼ Continued execution of comprehensive, enterprise-wide lifecycle asset management

◼ The need for a more responsive, resilient enterprise

◼ The need for more efficient, effective execution

More than half of DOE/NNSA facilities are not in sufficient condition to serve mission needs (e.g., poor or 

very poor condition). Nearly 25 percent are in fair condition and must be vigilantly maintained to avoid 

degradation (see Figure 6–3). Nearly 60 percent of facilities are more than 40 years old, nearly 30 percent 

of facilities were constructed during the early Cold War era, and 8 percent are deemed excess to mission 

needs. The success of DOE/NNSA’s unique national security mission depends on creating a safe, reliable, 
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and modern infrastructure. However, the current state of DOE/NNSA’s infrastructure poses risk to the 

availability, capacity, and reliability of Weapons Activities capabilities.

Figure 6–3. Asset condition by replacement plant value percentage

The Need for Enterprise-Wide Lifecycle Asset Management

Though major production capabilities have received strong support, DOE/NNSA must appropriately 

prioritize sustainment of all capabilities that enable Weapons Activities programs throughout the lifecycle 

of those capabilities. Going forward, DOE/NNSA must balance executing a handful of high-visibility 

megaprojects needed to produce strategic materials and recapitalizing the many smaller components or 

systems and facilities necessary for the design, production, and qualification of U.S. nuclear weapons

components. Additionally, DOE/NNSA continues to invest in and sustain facilities and capabilities to 

support important nonproliferation and counter-terrorism missions at DOE/NNSA.

DOE/NNSA’s assets include over 5,500 facilities, including major programmatic, office and laboratory 

buildings, electrical distribution systems, and security infrastructure. More than half of those assets are 

currently in insufficient condition and beyond their life expectancy. Upgrading or replacing aging 

infrastructure will require significant and sustained investment. By addressing infrastructure needs, 

DOE/NNSA can improve the overall condition of the physical infrastructure, increase efficiency of 

operations, and improve worker morale thereby increasing the ability to attract and retain the 

next-generation workforce.

A More Responsive, Resilient Enterprise

Supporting multiple concurrent warhead modernization programs requires a more responsive and 

resilient infrastructure. The modern nuclear security enterprise lacks resiliency, and aging facilities and 

equipment present a risk to mission execution. Further, the existing infrastructure lacks the capacity in 

some areas to meet emerging mission requirements, with the result being that the enterprise may not be 

sufficiently responsive for future anticipated mission.

To meet expected future demands, DOE/NNSA’s challenge is to transform the infrastructure so it is

responsive and resilient enough to enable development and deployment of new weapon designs and 

refurbishments more rapidly and at lower risk than is currently possible. This transformation also includes 

continued sustainment and advancement of the DOE/NNSA’s research and development (R&D) 

capabilities to facilitate technological advancements to support the future stockpile. 
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More Efficient, Effective Execution

DOE/NNSA is taking steps to addressthe declining state of infrastructure through enhanced and optimized

resources, including use of innovative management tools to facilitate a data-driven, risk-informed 

planning process to guide investment decisions. Sites are also making investmentsto recapitalize facilities 

and equipment in support of multiple capabilities. The nuclear security enterprise demands best-in-class

safety and physical security practices, emergency preparedness and response, and enhanced 

cybersecurity to counter the unexpected. Additional investments in these areas ensure those demands 

are met.

The remainder of the chapter describes how DOE/NNSA is resolving these challenges through continuing 

improvements in data-driven long-term planning and project execution.

6.2 Infrastructure Planning and Asset Management

Infrastructure planning and asset management covers the 

planning phase for operational and capital investment needs. 

Operational planning involves the maintenance, repair, and 

operation of facilities, utilities, and equipment at the sites. 

Strategic investment planning includes major system upgrades 

and replacement. Capital investment planning involves 

identifying future and anticipated emerging needs in the weapons 

programs, as well as science and technology investments to 

support those missions into the foreseeable future. Operational 

and capital investment planning must work in tandem to achieve 

the desired balance and cost-effectiveness that reflects capable 

asset management.

DOE/NNSA has taken considerable action over the last 5 years to 

better understand the nuclear security enterprise’s long-term strategic investment needs. DOE/NNSA is 

using data driven, risk informed tools to better pinpoint when and where infrastructure investments are 

needed. These tools are reducing mission risk by improving decision making, increasing buying power, 

and accelerating delivery. Direct mission needs are integrated and aligned with routine infrastructure 

sustainment and renewal processes to create a comprehensive plan for long-term investments. 

Bottom-up planning across the nuclear security enterprise is completed through area planning, described 

below, and deep dive reviews. Asset management software has provided accessible data for maintenance 

and sustainment-needs planning. Because of this expanded, more integrated planning, DOE/NNSA has a 

comprehensive understanding of the state of its physical assets and the actions needed to acquire, 

sustain, recapitalize, and dispose of its assets. These processes are also aligned with industry standards.

The asset management lifecycle, shown in Figure 6–2, is the basis for all investment planning within 

DOE/NNSA. It can be applied to a single facility or, if applied to numerous facilities, it can be used to 

organize the way the infrastructure program operates. The elements of the cycle must remain in balance 

to allocate resources appropriately to optimize the nuclear security enterprise’s ability to accomplish the 

mission and keep the nuclear security enterprise assets healthy. While the model appears 

straightforward, the processes used to achieve that balance across multiple facilities for the purpose of 

meeting multiple competing priorities are not. The following sections include some definitions of terms 

and background to understand these intricacies and to aid in understanding the nuclear security 

enterprise’s broad extent of investment planning and execution.
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6.2.1 Area Planning

The newest element of DOE/NNSA’s planning process is area 

planning, which connects DOE/NNSA’s Strategic Vision for the 

future nuclear security enterprise with planned infrastructure 

investments. The area plans provide detailed information on the 

lifecycle management strategies of co-located or functionally 

similar facilities, buildings, and other structures at each site. Area 

plans are part of an integrated planning process that flows from 

high-level requirements to interdependent project plans. 

Frequent communication among stakeholders at all levels through 

infrastructure deep dives and other forums keeps the planning 

process in alignment with DOE/NNSA mission needs. Area plans 

consider multiple funding sources and are regularly updated to 

reflect the latest developments and priorities.

DOE/NNSA and its management and operating (M&O) partners have developed area plans which align 

mission capabilities with associated assets across the nuclear security enterprise. These area plans 

showcase important elements of each capability’s long-term infrastructure plans and span direct mission 

and mission-enabling capabilities. They cover a myriad of topical areas, from flagship experimental 

facilities, weapon component production facilities, to utilities and emergency services. When viewed 

collectively, area plans provide a roadmap for modernizing DOE/NNSA infrastructure to deliver the 

mission.

6.2.2 Weapons Activities Line-Item Planning Integration

The Weapons Activities line-item planning integration process 

establishes procedures to consolidate the line-item data 

collection process and synchronize infrastructure planning 

across Weapons Activities programs. The integrated planning 

process is conducted in collaboration with the DOE/NNSA 

laboratories, plants, and sites to identify and prioritize major 

line-item construction projects for Weapons Activities 

programs. This prioritization informs near- and long-term 

planning efforts for programmatic and mission-enabling 

construction projects. It also informs the Future Years Nuclear 

Security Program programming and budgeting process as 

projects reach appropriate milestones.

Programmatic infrastructure investments are linked to 

mission-specific capabilities within Weapons Activities, such as 

plutonium modernization. They address investment needs for 

direct programmatic infrastructure including facilities, 

computers, diagnostic equipment, weapon-related production 

facilities and equipment, or anything else that enables the nuclear security enterprise to carry out 

research, testing, production, and sustainment activities to meet its national security missions. In 

contrast, mission enabling infrastructure provides support for programmatic activities, including general 

purpose office buildings, site-wide support facilities, utilities, and equipment. Both types of investments 

are required to sustain Weapons Activities capabilities in the near-term and for the foreseeable future.

Savannah River Site (SRS) Transition 

As the SRS mission requirements for 

DOE/NNSA increase and DOE’s Office 

of Environmental Management 

progresses toward a defined end state of 

the site’s clean-up mission, the primary 

authority, accountability, and site 

stewardship responsibility for SRS is 

planned to transition to DOE/NNSA by 

2025. An implementation plan for the 

necessary infrastructure, contract, and 

budgetary transfers is underway.

DOE/NNSA Construction Categories

Line-item – a construction project with total 

estimated cost greater than the minor 

construction threshold, so called because the 

project requires its own line-specific 

authorization and appropriation by Congress.

Minor Construction – any plant project not 

specifically authorized by law for which the 

approved total estimated cost does not 

exceed the minor construction threshold of 

$30 million.

Institutional Minor Construction – a minor 

construction project that addresses an 

institutional, multi-program, general site need 

rather than a specific program need, using 

funding derived from indirect cost pools.
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Consolidating line-item investment proposals combine 

multiple data collection processes currently in use and 

ensures a consistent, repeatable planning process for all 

line-item construction projects. The program offices’ 

comprehensive review of project proposals prior to 

Critical Decision (CD)-0, Approve Mission Need, ensures

all current and proposed line-item construction projects 

(detailed in Sections 6.3.1–6.3.2) represent necessary 

investments to support the program of record. The cost 

estimation process for proposals within capital 

acquisition has been improved by the Cost Estimating 

and Analysis Group (CEAG) and is further described in 

Chapter 8, Section 8.9.3.

6.2.3 Critical Decision Acquisition Milestone Process

A basic understanding of DOE’s CD acquisition milestone process is integral to understanding current and 

planned line-item construction projects and major item of equipment (MIE) projects. DOE Order 413.3B, 

Chg 6, outlines a series of staged approvals for line-item and MIE projects greater than $50 million, each 

of which is referred to as a CD. Each CD stage requires specific deliverables prior to and during the process 

to progress to the next stage. Figure 6–4 shows the four phases of the CD process (Initiation, Definition, 

Execution, and Closeout), with their corresponding CD stages.

Figure 6–4. Critical Decision process

Cost Estimating and Analysis Group (CEAG)

The CEAG, a DOE/NNSA organization led by 

headquarters and including cost estimating 

experts from each DOE/NNSA site, aims to

improve programmatic cost estimating capabilities 

across the nuclear security enterprise. To 

improve cost estimating for line-item capital 

acquisition projects, CEAG developed a Capital 

Acquisition Estimating Framework reminiscent of

that developed for weapons modernization to 

ensure consistent program cost estimating 

support and improved data stewardship among 

headquarters and the sites.
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Activities prior to CD-0, Approve Mission Need, through approval of CD-1, Approve Alternative Selection 

and Cost Range, constitute the Definition Phase. These activities are prerequisites to commencing the 

Execution Phase, which includes approval of CD-2, Approve Performance Baseline, approval of CD-3,

Approve Start of Construction, and activities up to CD-4.

2

 Approval of CD-4, Approve Start of Operations 

or Project Completion, reflects project completion based on previously determined criteria and the 

approval to transition to operations. DOE/NNSA Supplemental Directive 413.3 provides further guidance 

on this process, including that DOE/NNSA typically combines CD-2 and CD-3. The beginning of CD-4 marks 

the transition into the Closeout Phase. The approval of CD-4 is predicated on the readiness to operate 

and maintain the system, facility, or capability. Transition and turnover do not necessarily terminate all 

project activities. In some cases, it marks a point at which the operations organizations assume 

responsibility for operating and maintaining the new facility.

6.3 Acquisition

DOE/NNSA has more than 5,500 facilities with an average age of 

47 years. Many of the largest and most complex facilities will 

require line-item construction projects to accomplish 

modernization or replacement. Since aging facilities represent 

increasing risk to mission execution and line-item projects 

require significant coordination and funding over multiple years, 

DOE/NNSA continues to evaluate line-item construction project 

proposals as a part of the overall 25-year plan for Weapons 

Activities to identify for decision-makers the long-term funding 

levels required to replace infrastructure that has or will be aging 

out in that time period.

DOE/NNSA also actively works to improve its acquisition process 

to make efficient use of the funding that is provided. For 

example, DOE/NNSA recently launched two initiatives with the goal of streamlining design and acquisition, 

while decreasing cost and schedule impacts.

Enhanced Minor Construction and Commercial Practices (EMC2)

In 2019, DOE/NNSA launched the EMC2 pilot, which is successfully piloting a streamlined approach to 

executing $25–$50 million line-item projects that utilize a tailored DOE Order 413.3B processes. The pilot 

has established a new, streamlined process for a class of commercial-like, low-risk, low-cost construction 

using the International Building Code, Federal Safety Regulations (e.g., 10 Code of Federal Regulations 

[CFR] 851), and the Federal Acquisition Regulation as the framework. The EMC2 pilot is challenging nuclear 

security enterprise historical processes to create a streamlined process for acquiring non-complex, 

non-nuclear capital construction projects. Key elements of the approach include: 

◼ Clearly defining decision making authority, project supervision, direction, and oversight to the 

lowest levels to prevent redundancy and miscommunication

◼ Applying commercial construction standards and streamlining Environment, Safety, and Health 

requirements to match the project risks to project complexity

◼ Simplifying the project delivery model for some similar DOE/NNSA projects

2 See DOE Order 413.3B for details regarding projects requiring long-lead procurement. If long-lead procurements are executed 

prior to CD-3 approval for the project, this is designated as CD-3A and requires an additional stand-alone CD by the Project 

Management Executive.
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Cost savings up to 31 percent were realized on the 

four pilot projects. An additional six EMC2 projects 

that support vital mission work are projected to result 

in estimated cost savings of 20–40 percent. In 

support of increasing buying-power and accelerating 

delivery, the EMC2 pilot is testing and measuring the 

effectiveness of using existing successful minor 

construction project management instead of 

standard DOE Order 413.3B requirements and using 

commercial practices for oversight (e.g., 

Occupational Safety and Health Administration-like 

safety) for non-complex projects. This approach 

aligns with the fiscal year (FY) 2018 National Defense 

Authorization Act mandate to streamline the process 

for construction of non-nuclear facilities that have a 

total estimated cost of less than $100 million. A DOE/NNSA Supplemental Directive which incorporates 

EMC2 processes for non-nuclear, non-complex construction projects with a Total Project Cost less than 

$100 million is in the process of being issued. Ongoing and proposed projects that are making use of the 

EMC2 pilot are indicated in Section 6.3.2, Mission Enabling Construction.

Standardized Acquisition and Recapitalization (STAR) 

The goal of the Standardized Acquisition and Recapitalization (STAR) initiative is to simplify the design and 

delivery of commercial-like buildings starting with small offices and light laboratories while meeting DOE 

standards, such as the Guiding Principles for Sustainable Federal Buildings. It has two elements: 

◼ Design Library: STAR has created a library of concept-level designs that are submitted by sites, 

owned by DOE/NNSA, and can be reused or referenced by any site. By the end of 2022, there 

were 20 designs in the library, 10 STAR projects underway, and three more planned. Reusing 

successful designs is expected to save time and money. 

◼ Design Criteria: LANL and Nevada National Security Site (NNSS) are leading the development of 

unified design standards and creating a standard design process for office buildings that can be 

used by all sites. By the end of 2021, they delivered conceptual designs for two buildings, each 

with construction estimates under $25 million, and completed their detailed designs in FY 2023. 

This initiative has expanded to include conceptual design for a $50 million building. Moving 

forward, the remaining six sites’ criteria and processes will be reviewed and incorporated into the 

current model to create an Enterprise-wide standard.

In addition to the EMC2and STAR initiatives, DOE/NNSA continues to review line-items across the nuclear 

security enterprise to better ensure infrastructure is in place to meet mission requirements, while 

improving DOE/NNSA’s facility condition and reducing the average facility age to a sustainable level. 

Figure 6–5 shows the DOE/NNSA’s facilities’ historical average age growth and the planned reduction in 

average age after completing the projects described in the following sections. The average age calculation 

considers all DOE/NNSA facilities.

Management and Performance

DOE/NNSA is committed to encouraging competition 

and increasing the universe of qualified contractors by 

streamlining major acquisition processes. DOE/NNSA 

will continue to focus on delivering timely, best-value 

acquisition solutions for all programs and projects, by 

using a tailored approach to contract structures and 

incentives that are appropriate for the special missions 

and risks at each site. DOE/NNSA continues to: 

• Lead improvements in contract and project 

management practices

• Provide clear lines of authority and accountability

• Improve cost and schedule performance
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 6-10

Figure 6–5. Historical and projected average age of all DOE/NNSA facilities

This section discusses the current and planned line-items for the nuclear security enterprise. 

Programmatic line-items are presented by Weapons Activities capability area, followed by 

mission-enabling line-items. The third section details other recent acquisition efforts undertaken by 

DOE/NNSA.

6.3.1 Programmatic Construction

Programmatic construction projects are categorized according to the Weapons Activities programs, which 

are detailed in Chapters 3, 4, and 5. The Stockpile Management Program does not fund programmatic 

construction projects. Sections 6.3.1.1–6.3.1.3 describe current and proposed line-item projects within 

each program, including their projected schedules and cost ranges. Project proposals (Pre-CD-0) capture

potential mission gaps and emerging requirements across the nuclear security enterprise. However, they 

have not yet formally achieved approval of their mission need (per the CD process) nor accomplished the 

alternatives analysis to determine the best way to meet the need. The projected schedules and cost 

ranges shown represent one potential planning scenario and may change in future Stockpile Stewardship 

and Management Plans (SSMPs) as stockpile and enterprise requirements are refined and alternatives are 

formally assessed.

6.3.1.1 Production Modernization

Line-item projects in this section encompass the suite of subprograms within Production Modernization, 

including Primary Capability Modernization, Secondary Capability Modernization, Tritium and Domestic 

Uranium Enrichment, Non-Nuclear Capability Modernization, and Warhead Assembly. Additional 

information about these subprograms can be found in Chapter 3. Current planning estimates and 

schedule dates for projects in this program are listed in Figure 6–6.
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Figure 6–6. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Production Modernization

The Production Modernization program is currently executing 10 programmatic line-item construction 

projects that are past CD-1. Cost and schedule estimates for these projects vary from conceptual 

design-based estimates to baselined project estimates:

◼ The Chemistry and Metallurgy Research Replacement (CMRR) project will maintain continuity in 

enduring analytical chemistry and materials characterization capabilities for DOE/NNSA 

actinide-based missions, such as pit production, and to maintain LANL as the Nation’s Plutonium 

Center of Excellence missions. Active subprojects include reconfiguring space and installing 

additional analytical chemistry and materials characterization equipment in the Radiological 

Laboratory Utility Office Building and in the Plutonium Facility (PF-4).

◼ The Transuranic Liquid Waste Facility will support transuranic liquid waste treatment, which is a 

key support capability for DOE/NNSA operations at PF-4 at LANL. The current facility that treats 

liquid waste is past its useful life and does not meet current codes requirements. The Transuranic 

Liquid Waste Facility is designed to receive up to 29,000 liters of liquid waste annually from PF-4 

operations, which produces pits for the Nation’s enduring stockpile.
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◼ The Technical Area (TA)-55 Reinvestments Project, Phase 3 has begun and supports design and 

construction for new fire alarm systems in PF-4 at LANL and removal of the old system. Due to 

the current system’s age, replacement parts are no longer readily available, adding risks to the 

program.

◼ The High Explosive Science and Engineering 

(HESE) Facility will construct three new 

buildings to qualify and surveille high 

explosives, provide a technology development 

laboratory and office space for technical staff. 

It will replace 15 current Manhattan Project-era 

facilities at the Pantex Plant (Pantex), support 

the high explosives (HE) Center of Excellence 

for Manufacturing mission for DOE/NNSA, and 

help sustain high-quality scientific staff. The 

average age of the facilities to be replaced is 68 

years old. The HESE facility will be 

approximately 73,000 square feet. Project 

design is complete and received CD-2 and -3 

approval in April 2022. Site preparation and long lead procurement activities began in FY 2021. 

The main works contract has been awarded and construction started in May 2022.

◼ The Los Alamos Plutonium Pit Production Project (LAP4) will support plutonium pit production 

at LANL. The LAP4 project replaces aging and outdated equipment with pit manufacturing 

equipment in the PF-4 at LANL to increase throughput. LAP4 achieved CD-2 and -3 for the 

Decontamination and Decommissioning subproject in the first quarter of FY 2022. Additionally, 

CD-3a was approved for long lead procurement of gloveboxes to support the 30 pits per year

equipment subproject.

◼ The Savannah River Plutonium Processing Facility (SRPPF) will support plutonium pit production 

by repurposing the former Mixed Oxide Fuel Fabrication Facility into a safe, secure, compliant, 

and efficient pit production facility. The former Mixed Oxide Fuel Fabrication Facility is a Security 

Category I/Hazard Category II3structure that provides an opportunity to achieve pit production in 

a facility designed to meet stringent security and safety requirements for plutonium operations. 

The Savannah River Plutonium Processing Facility will provide a sustained production capacity of 

no fewer than 50 War Reserve pits per year as close to 2030 as possible at SRS. The project 

achieved CD-1 in FY 2021.

◼ The Uranium Processing Facility (UPF) project will complete the Uranium Mission Strategy’s first 

phase and ensure the long-term viability, safety, and security of DOE/NNSA’s enriched uranium 

capability. It will provide a modernized capability to manufacture weapon subassemblies 

containing enriched uranium components and convert excess enriched uranium into forms 

suitable for safe, long-term storage and reuse. The new facility will support Y-12 National Security 

Complex’s (Y-12) enriched uranium processing capabilities currently located in Building 9212, 

which is an original Manhattan Project-era facility that is degraded, poorly configured to meet 

today’s strategic needs, and poses multiple risks to meeting the mission.

3 A Security Category I facility is one designed to contain certain quantities of strategic special nuclear materials that trigger the 

most rigorous level of security protections. Hazard Category II facilities are those for which a hazard analysis shows the potential 

for significant off-site consequences in the event of an accident. 

Construction on the High Explosive Science and 

Engineering Facility at Pantex
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Manhattan Project-era Building 9212 at Y-12 (left) and construction on its replacement, the Uranium Processing 

Facility, in September 2022 (right)

◼ The High Explosives Synthesis, Formulation, and Production Facility (HESFP) project at Pantex

will establish HE production capability within the nuclear security enterprise to address the need 

to meet DOE/NNSA production requirements. This project will consolidate limited legacy facilities 

that are inadequate for the mission need and will ensure the required capability and capacity is 

available to meet the future HE workload and mission requirements. Areas to be addressed 

include explosive and mock formulation operations to support multiple weapon programs, 

technology development for future programs, and support for strategic partners. CD-1 was 

awarded in February 2021. However, as DOE/NNSA is facing issues like higher-than-expected 

inflation and supply chain and craft worker shortages while executing multiple large construction 

projects in parallel at individual sites, DOE/NNSA rebalanced line-item construction portfolio in 

recognition of the nuclear security enterprise’s capacity to execute construction. As this project 

can be deferred at this time without significant mission impact, it is planned to be paused between 

FY 2024–2026.

◼ The Lithium Processing Facility (LPF) will construct a new facility to replace lithium processing 

capabilities in Building 9204-2 at Y-12. At 80 years old, the current lithium facility is one of the 

oldest operating facilities in the nuclear security enterprise. Until the new LPF is operational and 

qualified, much of the risk to lithium sustainment is associated with the existing facility’s age and 

degradation. A site for LPF has been selected at Y-12 and the former Biology Building was 

demolished to make room for this project. Lithium process design is 60 percent complete. Facility 

design and site civil exploratory boring activities have commenced. 

◼ The Tritium Finishing Facility (TFF) project at SRS will construct two new process buildings and 

relocate the reservoir-related and other capabilities from the current 65-year-old facility to the 

newer, centralized facilities. This alternative will significantly increase facility reliability specific to 

natural phenomena hazards, addressing Defense Nuclear Facilities Safety Board concerns. While 

30 percent design completion was authorized for the overall project, the need to prioritize staffing 

for SRPPF at SRS led DOE/NNSA to pause TFF from FY 2024–2026. Funding carried over from 

FY 2023 will be used to complete site preparation work and 30 percent overall project design, as 

well as 60 percent of classified process design, to better position the project for resuming in 

FY 2027. 

◼ The Power Sources Capability (PSC) project will support all current and planned nuclear weapon 

systems that require power source research, development, design, qualification, production, and 

surveillance activities. Requirements for these power sources are stringent and unique to nuclear 
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weapons, and very few commercial suppliers are viable for this work. The current facility cannot 

meet anticipated mission requirements due to increasing workload and poor facility condition, 

which poses increasing risks to meeting weapon program deliverables. DOE/NNSA also supplies 

advanced power sources for other national security mission needs that cannot be commercially 

sourced. This project will mitigate risk by establishing a new facility that is adaptable to changing 

needs, enables engagement with supply chain partners, supports technology development, and 

fosters innovation.

The following programmatic line-item projects under Production Modernization are in the Definition 

Phase of the CD process (CD-0 to CD-1):

◼ The Domestic Uranium Enrichment (DUE) project will analyze options for (and if necessary, 

establish) a reliable and economic supply of enriched uranium to support U.S. national security 

needs. The U.S. Government does not currently have the capability to enrich uranium for defense 

missions.

◼ The Energetic Materials Characterization (EMC) project will support R&D to advance predictive 

capabilities for safety and performance assessments, component qualification and surveillance, 

evaluate material responses to all aspects of the stockpile-to-target sequence, resolve significant 

finding investigations (SFIs) involving energetic materials, provide technical data on which to base 

annual weapon assessments, and develop new/replacement materials to support evolving HE 

technical requirements. The project will consolidate 18 structures at LANL into a single modern 

facility to increase operational efficiency and reduce operating costs. However, as DOE/NNSA is 

facing issues like higher-than-expected inflation and supply chain and craft worker shortages

while executing multiple large construction projects in parallel at individual sites, DOE/NNSA 

rebalanced line-item construction portfolio in recognition of the nuclear security enterprise’s 

capacity to execute construction. As this project can be deferred at this time without significant 

mission impact, it is planned to be paused between FY 2024–2026.

◼ The Radiography/Assembly Capability Replacement (RACR) project received CD-0 approval in 

October 2022. However, an integrated project team has since been tasked to investigate 

alternative strategies of meeting the program requirements in lieu of a single line-item 

investment. The pre-analysis of alternatives effort is underway to support acquisition, and further 

decisions have yet to be made regarding a path forward and preparation for initial design and 

baseline cost. Once constructed, RACR will consolidate existing assembly and radiography 

operations, currently conducted in a multitude of facilities dating to the 1950s. Safety, security, 

schedules, and quality assurance will all improve with RACR, while risk to the public, workers, and 

program will decrease. RACR will position the DOE/NNSA nuclear weapons program for nuclear 

explosive package assembly and radiography capability for the next 40 to 50 years for all site and 

surveillance mission assignments.

◼ The Material Staging Facility (MSF) at Pantex was placed on hold in April 2021. The project will 

provide a new safe, secure, and sustainable below-grade facility adjacent to Zone 12 South 

Material Access Area that meets weapon and special nuclear material (SNM) component staging 

capacities for the next 75 to 100 years. Prior to the project being placed on hold, SRS surplus 

plutonium material and Hanford Unirradiated Fuel Packages were also planned into the project. 

Significant cost reduction can be realized in the project with these items removed from 

consideration now that the State of South Carolina has settled its lawsuit with DOE. It will include 

shipping and receiving docks for SNM, and for transporting weapons in the Mobile Guardian 

Transporter and Safe Secure Transport.
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In addition to projects in the Definition and Execution Phases, Production Modernization is considering 

several programmatic line-item proposals (Pre-CD-0). These project proposals are a part of the planning 

process, but should not be considered part of the program of record until they achieve appropriate 

approvals. Scope descriptions are illustrative, with DOE/NNSA evaluating options during the Analysis of 

Alternatives and making decisions at CD-1:

◼ The Agile Radiation Case and Component Capability (ARCCC), formerly the Depleted Uranium 

(DU) Manufacturing Complex, would consolidate several processes required to meet the DU 

mission, and replaces capabilities currently located in other buildings. DU production facilities 

that support canned subassembly production at Y-12 were constructed in the 1940s and 1950s. 

These facilities perform production work for DU, and general manufacturing and are vital to 

canned subassembly production. They are oversized for today’s mission, do not meet current 

codes and standards, are costly to operate, have many operating issues, and have exceeded their 

expected life. These facilities must be upgraded or replaced to ensure continued mission 

availability and to reduce annual operating costs.

◼ The Product Realization Infrastructure for Stockpile Modernization (PRISM) facility, formerly the 

Next Generation Life Extension Program (LEP) Research and Development Component Fabrication 

Facility, is a joint design agency-production agency-owned collaborative space and testbed that 

can assess, develop, tailor, and transition new manufacturing technologies and designs that would

enable DOE/NNSA to accelerate the development and production of non-nuclear components for 

future modernization programs.

◼ The Tritium Development Laboratory (TDL) would reestablish the radiological research and 

development capability required for maturation and de-risking of new tritium and gas transfer 

system (GTS) processing technologies to meet mission requirements, address obsolescence, 

increase efficiency, and maintain core competencies. A DOE/NNSA study is underway to assess 

current capabilities across the DOE to establish whether TDL is needed. Due to this ongoing study, 

the proposal is not included in Figure 6-6 above.

◼ The Microelectronic Components Capability (MC2) project, formerly the Heterogenous 

Integration Facility, would provide modern and agile clean room space to support microelectronic 

design and production at the Microsystems Engineering, Science, and Applications (MESA) 

complex at SNL. Determination that a new facility is needed is based on analysis of MESA’s age 

and space limitations, the rapid evolution of microelectronics fabrication technologies, and 

expectation of the potential need to continuously produce Trusted and Strategic RadiationHardened microelectronics while simultaneously installing new fabrication and production 

capabilities. The proposed facility would provide state-of-the-art cleanroom space, integrate a 

variety of microelectronic technologies, and would accommodate the evolving tool-size platforms 

that are not possible in the current MESA complex.

◼ The Neutron Generator Enterprise Consolidation project would optimize manufacturing by 

consolidating existing facilities for neutron generator operations that are currently conducted in 

several buildings across multiple sites. Additionally, modernizing aging infrastructure and 

providing flexible-use space is needed to accommodate agile responses to advancing 

requirements and technology, develop material and personnel flows, improve efficiency, 

consolidate processes, and reduce redundancies, waste, and risks to mission work.

◼ The Consolidated Environmental Test Facility aims to upgrade, modernize, and consolidate 

environmental testing capabilities in support of stockpile modernization programs and limited life 

components associated with enduring the stockpile.
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◼ The California Environmental Test Revitalization project is intended to improve the efficiency, 

effectiveness, agility, and responsiveness of the California environmental test capabilities through 

structural upgrades to aging facilities to meet modern security standards and current energy 

codes.

◼ The Analytical Chemistry project would construct a stand-alone laboratory to replace the current 

analytical chemistry capabilities at Y-12 and remove the analytical chemistry laboratory capability 

from the future Enriched Uranium Manufacturing Center. This would enable replacement in an 

earlier year, and ensure the capability is viable to support all future mission requirements.

◼ The Test Capability Revitalization - Thermal Shock (Phase 3) and Test Capability Revitalization -

Vibration Blast (Phase 4) projects focus on large subsystem- and system-level test facilities in 

thermal, fire, acceleration, impact, shock, and other environments. Phases 3 and 4 would

renovate or replace existing capabilities and/or develop new capabilities at current facilities.

◼ The Integrated Technology for Advanced Manufacturing (ITAM) Campus project would create 

modern infrastructure with capabilities for development of advanced assembly system 

technologies (robotics and automation, welding, inspection, etc.) to accelerate deployment. 

ITAM would collocate several capabilities, including manufacturing, assembly, computing, 

characterization, and inspection expertise, in an open, collaborative space with the ability to 

elevate to secure, when needed.

◼ The Gas Transfer Systems and Surety (GTS/S) Laboratory would provide what is needed to meet 

GTSs and Surety enduring mission needs for future systems, such as the W93. The current facility 

is over 60 years old and has had several modifications made to temporarily shore up capabilities 

to meet past and current mission work. The future laboratory would provide a modern, lower 

maintenance structure capable of meeting the expanded, future demands of the weapons 

program. Work areas and equipment require an efficient layout and current state-of-the-art 

technology to meet future testing needs.

◼ The General Manufacturing Capability project would consolidate all the general manufacturing 

capabilities into a single, separate new build at Y-12. The non-nuclear general manufacturing 

operations provide components to support all secondary component fabrication, assembly, and 

inspection. Portions of the capability in the current facility have been identified for relocation to 

the future DU Manufacturing Center; however, this project would account for those processes

not currently identified for replacement.

◼ The Enriched Uranium Manufacturing Center (EUMC) would complete the second phase of the 

Enriched Uranium Strategy. The new facility would support Y-12’s enriched uranium processing 

capabilities. Functional Areas include machining, chip cleaning and conversion, dimensional 

inspection, and enriched uranium recycle and recovery operations.

◼ The Assembly and Disassembly Center project completes the third and final phase for the 

Enriched Uranium Strategy. The new facility would support Y-12’s enriched uranium processing 

capabilities. Capabilities include product certification, quality evaluation and surveillance, 

assembly of components, dismantlement and disassembly of components, radiography, and 

dimensional inspection.

◼ The Weapon Assembly/Disassembly Replacement Facility would focus on increasing throughput 

and efficiencies, lowering operating costs, and reducing the number Technical Safety 

Requirements controls during weapons assembly/disassembly operations at Pantex. Weapons 

assembly/disassembly includes assembly, disassembly, refurbishment, maintenance, and 
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surveillance of stockpile nuclear weapons and weapon components, as well as dismantlement of 

retired stockpile nuclear weapons. These weapon assembly and disassembly operations are 

conducted in 60 bay and cell facilities, as well as special purpose satellite facilities. The facilities 

are, on average, 47 years old with many facility systems using outdated technology and nearing 

the end of their useful life.

6.3.1.2 Stockpile Research, Technology, and Engineering (SRT&E)

Projects in this section, including both line-items and MIEs, encompass the suite of subprograms within

Stockpile Research, Technology, and Engineering (SRT&E), including Assessment Science, Engineering and 

Integrated Assessments, Inertial Confinement Fusion, Advanced Simulation and Computing, and Weapon 

Technology and Manufacturing Maturation. Additional information about these subprograms can be 

found in Chapter 4. Current planning estimates and schedule dates for projects in this program are listed 

in Figure 6–7.

Figure 6–7. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Stockpile Research, Technology, and Engineering

SRT&E is currently executing two programmatic construction projects that are past CD-1. Cost and 

schedule estimates for these projects vary from conceptual design-based estimates to baselined project 

estimates:

◼ The Advanced Sources and Detectors (ASD) project is an MIE that will fill the pulsed X-ray 

radiography capability gap through developing a multi-pulse linear induction electron accelerator. 

The scope includes design, technical maturation, fabrication, testing, installation, commissioning, 

and readiness execution at the U1a Complex (U1a). The ASD project achieved CD-3 in 

November 2022.

◼ The U1a Complex Enhancements Project (UCEP) comprised of two subprojects, UCEP10 and 

UCEP20, and will provide infrastructure modifications to the U1a at NNSS to house and field 
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multi-pulse radiography. This project includes structures, systems, and components necessary 

for deploying Enhanced Capabilities for Subcritical Experiment Advanced Sources and Detectors 

Project’s pulsed X-ray radiography equipment. UCEP10 achieved CD-4 in June of 2022. UCEP20 

achieved CD-2/3 in June of 2022. 

The following programmatic line-item project under SRT&E is in the Definition Phase of the CD process 

(CD-0 to CD-1):

◼ The Z-Pinch Experimental Underground System (ZEUS) Test Bed Facilities Improvement project

at NNSS includes the design, construction, and commissioning of the ZEUS Test Bed and systems 

to support dense plasma focus diagnostics. The area will be used for neutron diagnosed 

subcritical experiments. Due to changes in scope that have impacted the cost estimate, 

DOE/NNSA is requesting the conversion of the project from a minor construction project to a lineitem construction project. 

◼ The Combined Radiation Environments for Survivability Testing (CREST) project will provide an 

advanced radiation environmental test capability to fill a mission gap for R&D, qualification, and 

certification data in combined survivability/threat environments. The Annular Core Research 

Reactor’s (ACRR) current capability provides high-fidelity neutron and gamma-ray environments 

that emulate nuclear weapon environments to support weapons development and certification. 

Every weapon system in the stockpile undergoes testing at the ACRR and demand is increasing. 

The facility’s age and condition mean ACRR is unable to keep pace with demand. The proposed 

CREST project will provide a facility that will replace and enhance the legacy capability. This new 

facility will combine the current ACRR capabilities with an independent gamma-ray irradiation 

capability in a purpose-built facility specifically designed to meet current and future stockpile 

modernization needs.

In addition to projects in the Definition and Execution Phases, SRT&E is considering several programmatic 

line-item proposals (Pre-CD-0). These project proposals are a part of the planning process but should not 

be considered part of the program of record until they achieve appropriate approvals. Scope descriptions 

are illustrative, with DOE/NNSA evaluating options during the Analysis of Alternatives and making 

decisions at CD-1:

◼ Mesoscale Science Gap: The future of DOE/NNSA’s predictive models used in assessment of the 

U.S. nuclear stockpile, and qualification of materials for future weapons systems would be 

increasingly reliant on experimental data interrogating physics and chemistry at the mesoscale. 

The mesoscale (1–100 m) is the length scale in which many important materials, chemistry, and 

physics behaviors relevant to DOE/NNSA missions exist. Assessment of the future stockpile, 

maintenance of the current, aging stockpile, and qualification of new materials and manufacturing 

process changes will rely heavily on an understanding of materials behaviors at the mesoscale in 

weapons-relevant environments, particularly under the thermal, thermodynamic (including 

shock), and radiation environments encountered in the nuclear weapons. DOE/NNSA is pursuing 

a two-site strategy which would leverage the multi-billion dollar investments from the DOE’s 

Office of Science to address this mesoscale science gap: (1) The Dynamic Materials Properties 

Laser (DMPL) is an MIE that would be a high energy (5 kilojoule) long pulse laser capability in 

partnership with the DOE’s Office of Science/Fusion Energy Sciences to complement the Matter 

in Extreme Conditions-Upgrade line-item project at the Linac Coherent Light Source, and (2) The 

Defense Materials Science Sector (DMSS) would feature a dynamic experiments hutch in addition 

to a materials science and qualification hutch using enhanced X-ray properties from the Advanced 

Photon Source – Upgrade project.
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◼ The Los Alamos Neutron Science Center (LANSCE) Modernization Project (LAMP) would replace 

technologically obsolete and high-risk accelerator systems with modern, sustainable technologies 

to ensure that LANSCE continues to provide a robust capability for dynamic multi-frame proton 

radiography, neutron scattering on defense-relevant materials, neutron radiography of 

components and subsystems, and nuclear physics on defense-relevant isotopes. The LAMP scope 

would address LANSCE accelerator end-of-life system failures and technology obsolescence by 

modernizing major accelerator systems to optimize beam quality and performance. This 

modernization would improve reliability, maintainability, efficiency, sustainability, and 

performance, while ensuring the ability to increase scheduled beam time to LANSCE science 

stations to meet increased demand. The LANSCE facility’s unique capabilities will enable 

resolution of SFIs, assess the stockpile, evaluate and qualify components for the future stockpile, 

assess foreign systems, analyze historic and current experiments, and improve computational 

models. The facility continues to function as a user facility for scientific studies.

◼ The Increased Laser Power and Energy on National Ignition Facility (NIF) project would upgrade 

the NIF laser, which is currently operating at its highest sustained levels of energy and power to 

date, made possible only by continued investments in optics and laser technology. Recent ignition 

experiments show that small increases in laser energy could substantially increase fusion output. 

Four energy and power upgrade paths are being assessed within the limitations of the current 

facility.

◼ The New High Energy Density (HED) Capability Support Facility Replacement project would 

support experimental throughput for the national user facility at NIF with a building that would 

house key functions such as production and fabrication for targets, diagnostics, and optics in 

support of HED physics experiments. The new building would provide advanced clean room and 

laboratory facilities for the next generations of targets and diagnostics for HED physics.

◼ For the Next Generation Pulse Power (NGPP) facility, major gaps exist in high-energy X-ray and 

neutron sources to test the performance of circuit boards and other large components in the 

hostile threat environments that a nuclear weapon could experience. There are also gaps in the 

energy and power required to access the full range of high-energy density conditions relevant to 

the nuclear explosive package. The proposed NGPP facility would help close the aforementioned 

mission gaps, while ensuring the safety and effectiveness of the nuclear stockpile by addressing 

the shortcomings and limitations of the aging Z pulsed power facility (Z).

◼ The Engineering-Data Analytics Facility (EDAF) would enable data collection, storage, and 

analysis capability by bringing together high-performance computing (HPC), high-performance 

data-analytics, a scalable data enclave, and an extreme-speed network backbone. These 

capabilities would enable full-system engineering models (sometimes called digital twins) that 

would be automatically evaluated to explore combined environments, manufacturing issues, 

aging materials, and as-fielded conditions, with the results informing additional physical and 

computational evaluations, design options, and stockpile actions.

◼ The Sigma Replacement Facility project would construct new facilities to maintain and enhance 

capabilities for the many Stockpile Stewardship support roles that Sigma currently fulfills. These 

facilities would include the Integrated Technology Testbed for Advanced Manufacturing for 

developing transformative production technologies and three additional facilities that would 

support uranium foundry operations, replace LANL main shop capabilities for non-nuclear 

components, and enable beryllium fabrication capability in a building with appropriate ventilation 

scaled to support the projected size of future mission need.
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◼ The Advanced Manufacturing Process Development Capability Sustainment project would 

provide for high bay laboratory space to accommodate advanced additive manufacturing research 

and production-capable manufacturing tools, while also addressing electrical and fabrication 

laboratories in a reconfigurable space that facilitates agile and rapid product realization. The 

current facility is in a substandard state and continues to deteriorate. A recent evaluation of the 

facility indicates the need to replace flooring, air handlers, and water and sanitary systems, as 

many of these systems have exceeded their initial design life. By FY 2031, the facility will be over 

40 years old and will require a substantial investment to sustain this capability, consistent with 

industry standards.

◼ The Full Replacement of Saturn and High-Energy Radiation Megavolt Electron Sources project

would involve the construction of a facility to replace the current capabilities of both. The project 

would include modified, upgraded, and enhanced accelerators; new buildings for high bay 

laboratory space, data collection and analysis laboratory space, and light electrical laboratory 

space; and support, storage, office, administrative, and conferencing space.

◼ The Next Generation Cinematographic Moderate Energy Radiography Capability project would 

upgrade the Building 851 open firing site to include a 10 mega-electron volt 20-pulse linear 

induction acceleration and a dense plasma focus for flash neutron radiography. This project 

would provide capability for cinematographic X-radiography that would enable X-ray movies for 

important weapons physics experiments, expand options for in-demand hydro tests, and deliver 

high-fidelity data for validating simulations.

6.3.1.3 Defense Nuclear Security

Line-item projects in this section fall under the Defense Nuclear Security (DNS) program. Additional 

information about DNS can be found in Chapter 5, Section 5.2. Current planning estimates and schedule 

dates for projects in this program are listed in Figure 6–8.

Figure 6–8. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Defense Nuclear Security4

DNS is currently executing one programmatic line-item construction project that is past CD-1. Cost and 

schedule estimates for this project is the baselined project estimate:

◼ The West End Protected Area Reduction (WEPAR) project will reduce the size of the protected 

area at Y-12 from 150 acres to approximately 90 acres. This project will have two beneficial 

outcomes. First, a new Perimeter Intrusion Detection and Assessment System will protect the 

sensitive facilities remaining within the now reduced perimeter, which will reduce security and 

operating costs. Second, DOE Office of Environmental Management cleanup activities for 

facilities previously encompassed by the larger protected area may proceed more efficiently and 

4 The CD-4 date of FY 2025 for WEPAR is subject to revision with the forthcoming project re-plan.
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cost effectively because those facilities will no longer be in a protected area. The project received 

CD-2/3 approval in January 2021.

6.3.2 Mission Enabling Construction

DOE/NNSA also funds mission-enabling infrastructure line-items that provide site-wide utilities, office and 

laboratory space, and other services that support the nuclear security enterprise missions (see Figure 6–9). 

These projects are required to meet daily operational needs across the nuclear security enterprise.

Figure 6–9. 25-year mission-enabling line-item schedule
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Recently completed mission-enabling line-item projects include: 

◼ The Emergency Operations Center at Lawrence Livermore National Laboratory (LLNL) provides a 

new permanent Emergency Operations Center with comprehensive emergency management 

capabilities for the development, coordination, control, and direction of emergency planning, 

preparedness, readiness, assurance, response, and recovery actions. The 20,000 square foot 

building will allow an occupancy capacity needed during an emergency event that the current 

Emergency Operations Center cannot accommodate, provide additional parking, and contain or 

interface multiple emergency and safety-related systems. This EMC2 pilot executed construction 

and achieved full operations in 24 months and was delivered ahead of schedule and under budget.

◼ The Fire Station project at Y-12 provides an approximately 30,000 square foot commercial 

standard building to meet all emergency response requirements including firefighting, emergency 

medical treatment and transport, hazardous materials spill mitigation, and technical rescue 

responses for all events within the site emergency response boundary at Y-12. The new facility 

will be built to meet all safety standards and building codes to support 24/7 operations under all 

environmental conditions. The facility will accommodate a workforce and a fleet including large 

fire apparatus vehicles, ambulances, emergency response vehicles, and other support vehicles. 

This project was executed as part of the EMC2 pilot. Construction began in FY 2021 and beneficial 

occupancy was completed in FY 2023.

◼ The TA-3 Substation Replacement at LANL provides increased distribution capacity, improved 

reliability, reduced maintenance, support for greater operational flexibility, and increased worker 

safety. 

◼ The Emergency Operations Center at Y-12 provides a centralized, comprehensive emergency 

management capability for the development, coordination, control, and direction of emergency 

planning, preparedness, readiness assurance, response, and recovery actions. The current facility 

is not compliant with DOE Order 151.1C, Comprehensive Emergency Management System. This 

project was executed as part of the EMC2 pilot utilizing streamlined processes for non-nuclear, 

non-complex projects.

The mission-enabling projects listed below are currently in the Execution Phase of the CD process. 

Fire Station at Y-12
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◼ The Emergency Operations Center at SNL will provide a facility that supports DOE/NNSA and SNL 

emergency operations, the 24/7 Emergency Management Communication Center, dedicated 

incident management and coordination space, multipurpose training rooms, and fuel and water 

storage sufficient to mitigate all potential emergency operations and management response 

capabilities. This project is being executed as part of the EMC2 pilot and the center is expected to 

be operational in Fall 2023.

◼ The 138 kilovolt (kV) Power Transmission System Replacement project will replace a 55-year-old 

138 kV power transmission system in the NNSS Mission Corridor in Mercury, Nevada. The project 

will provide the site with reliable power and communications to mission critical facilities by 

designing and constructing a new 138 kV power transmission system to replace and upgrade 26

Construction at the Emergency Operations Center at Y-12

Construction on SNL's Emergency Operations Center
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miles of the degraded existing power transmission system. It will also upgrade the collocated 

fiber optic lines to meet vital national security mission requirements.

◼ The Electrical Power Capacity Upgrade at LANL will address projected increases in the electrical 

demand to reliably support multiple program activities being performed at the site. Power 

demand for all programs is expected to exceed LANL’s existing transmission and distribution 

system’s capacity and performance requirements. This electrical upgrade will support critical 

Weapons Activities requirements for stockpile modernization programs, SFIs, ongoing stockpile 

stewardship programs, and other work.

◼ The Digital Infrastructure Capability Expansion project at LLNL will provide safe, secure, resilient, 

reliable, flexible, and sustainable infrastructure for LLNL’s networking and telecommunications 

digital infrastructure needs. The project will expand capabilities to meet growth projections for 

the next 40 years.

◼ The Plutonium Modernization Operations Complex at LANL will provide additional office 

workstations and associated common space for increased operations within TA-55 and other 

supporting plutonium modernization capabilities in TA-46, -48, -50, and -63. This complex 

encompasses the Plutonium Modernization Operations & Waste Management Office Building, 

the TA-46 Protective Forces Facility, and the Plutonium Production Building listed in Figure 6–9.

◼ The Special Materials Facility Utilities and Infrastructure subproject will provide infrastructure 

and utility upgrades at Y-12. This repurposed facility is necessary to support special materials 

processing and production for future mission requirements. The facility has received funding and 

approval for execution under an EMC2like acquisition approach. Project design commenced in 

FY 2022.

◼ The Analytic Gas Laboratory at Pantex would provide the safe, secure, and reliable infrastructure 

necessary to perform gas analysis at Pantex. Gas analysis is required to perform the 

dismantlement, surveillance, stockpile refurbishment, and nuclear non-proliferation missions at 

Pantex. 

There are multiple proposals for new mission enabling projects that are planned over the next 10 to 

25 years, some of which include the following. For projects subject to DOE Order 413.3C project 

management requirements, scope descriptions are illustrative, with DOE/NNSA evaluating options during 

the Analysis of Alternatives and making decisions at CD-1:

◼ The U1a Complex Access Shaft at NNSS would provide expanded access to the U1a underground 

needed to support a greater number of people, equipment, and experiments necessary to support 

the ongoing expansion of the science-based Stockpile Stewardship Program.

◼ The Maintenance Facility at Y-12 would replace the antiquated maintenance facilities that 

support all Y-12 production missions and would enable preventive, predictive, and corrective 

maintenance across the site. The new facility would consolidate maintenance processes and 

eliminate square footage of aging facilities in a more optimized, efficient location. 

◼ The National Security Innovation Center at LLNL would move staff out of dispersed, end-of-life 

Weapons Program office buildings into a more centralized location and would enable optimized 

use of space. Stockpile modernization efforts and future stockpile stewardship missions require 

multidisciplinary teams of scientists and engineers to develop, innovate, and apply sophisticated 

modeling and simulation tools to conduct high-fidelity experiments. The multidisciplinary team 

approach requires collocated weapons program staff equipped with quality classified 

workstations with modern information technology infrastructure.
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◼ The Weapon Engineering Science and Technology Laboratory at SNL-California would integrate 

the Materials Science and Engineering capabilities across materials development and engineering 

design. The primary existing facility is in poor condition, is functionally unfit for advanced 

materials science R&D, and lacks sufficient capacity to meet the current and projected demand. 

◼ The Production Maintenance Facility at Pantex would replace multiple facilities approaching the 

end of operational life expectancy and not located near critical Production and Production 

Support facilities. The new facility would consolidate maintenance processes and provide a more 

efficient location to support Production operations and facilities.

6.3.3 Other Acquisition Efforts

DOE/NNSA is also acquiring space through purchase and leasing. DOE/NNSA is executing multiple 

purchase acquisitions through various tools and expanding the use of NNSA acquisition authorities. 

6.3.3.1 Real Estate and Leased Facilities

Leases are an important real estate strategy to 

address short-term needs. DOE/NNSA is 

streamlining its process and refining its strategy 

to make better use of leasing as a tool for 

addressing temporary mission needs, while 

ensuring long-term needs are addressed in the 

most cost-effective manner. Leases provide the 

flexibility needed to deal with surges in mission 

work but can be more costly than construction 

and ownership if not well structured or if used 

as permanent solutions. DOE/NNSA is 

implementing a range of innovative tools and 

processes related to leasing strategies. The 

lease scoring system rolled out in early 2019 is 

driving better decision-making by offering an 

objective metric for evaluating a lease’s risk and 

comparing it within DOE/NNSA’s broader 

leasing portfolio. This system helped improve 

the terms and conditions in leases, minimize 

tenant improvements, and ensure exit 

strategies are in place for new leases. Lease 

scoring is also normalizing the solicitation for 

space to encourage better rates, as well as site 

visits to improve usage and ensure lessor is 

delivering per the lease.

DOE/NNSA is currently investigating solutions 

to address the following projects through 

similar innovative strategies: 

◼ The Northwest Las Vegas New Campus

will provide sustainable infrastructure 

that supports the health, safety, and 

Kansas City Short-Term Expansion Project

Since the consolidation of operations in 2014 from the original 

Bannister Road facilities to the leased facility on Botts Road, 

Kansas City National Security Campus (KCNSC) has seen a 

significant increase in workload in support of the nuclear 

stockpile modernization. The activities supporting the growth 

in workload have consumed all KCNSC’s factory space at the 

Botts Road facility and have driven KCNSC to address this 

shortfall by purchasing a nearby facility, KCNSC East

(previously known as Building 23) after previously bridge 

leasing the facility. The Kansas City Short-Term Expansion 

Project (KC STEP) is a series of multi-year projects that will 

provide for KCNSC East infrastructure upgrades, relocation of 

specific manufacturing capabilities to KCNSC East, establish 

new capabilities at KCNSC East, and expansion and 

rearrangement of other manufacturing capabilities remaining 

at the Botts Road main campus. While efforts continue to 

assess a long-term facility expansion strategy, KC STEP will 

provide increased factory capacity to support the B61-12 LEP

and W88 Alteration 370, as well as partially filling needs for the 

W80-4 and W87-1 programs.

KCNSC East Building
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welfare of NNSS employees, the public, and the environment.

◼ The Kansas City Non-Nuclear Expansion Transformation (KCNExT) will include a multi-year 

phased campus plan to achieve an expanded campus to provide additional manufacturing space 

to meet the needs for non-nuclear production for multiple modernization programs and 

consolidate existing Kansas City National Security Campus (KCNSC) office space and exit office 

space leases.

6.3.3.2 Direct Purchases

One recently developed tool is an Option agreement, a contract with the land/facility owner that gives a 

prospective buyer the exclusive right to purchase the property at a fixed price within a stated time period. 

The option agreement allows necessary time for DOE/NNSA to perform the due diligence required for any 

Federally funded purchase. 

DOE/NNSA executed its first “option purchase” acquisition in June 2020 and is preparing to pursue the 

purchase of other facilities across the enterprise. The purchase of 103 Palladium, a 73,000 square foot 

facility on a 21-acre campus in Tennessee will be repurposed as the John M. Googin Technology 

Development Facility to provide much needed footprint for the Y-12 Development program. In March 

2023, NNSA purchased Building 23 to support the KCNSC mission. This facility will help KCNSC meet 

mission demands and be more strategic with manufacturing space to accommodate near-term facility 

needs while supporting long-term manufacturing requirements. All will use existing Atomic Energy Act of 

1954 authorities to acquire facilities. 

6.4 Modernization Through Minor Construction and 

Recapitalization

This section describes how DOE/NNSA, in partnership with its 

M&O partners, modernizes assets to enable mission success and 

readiness; ensures operational safety and security;safeguards the 

workforce, public, and environment; and meets mission needs to 

support the nuclear security mission.

In addition to major acquisition and line-item construction, 

DOE/NNSA also uses minor construction and recapitalization to 

update infrastructure. This provides an important vehicle for 

DOE/NNSA to sustain major facilities and replace smaller capital 

assets below the $30 million line-item cost threshold. These 

projects are an effective method for making improvements to 

increase DOE/NNSA’s mission performance and lower operating 

costs. They can be completed much faster than line-item construction projects, and they enable 

DOE/NNSA to be responsive to emerging infrastructure issues and changing stockpile requirements.

Modernizing the nuclear security enterprise is accomplished through formal recapitalization programs 

planned and funded at the DOE/NNSA level, through site-directed investments as well as other funding 

mechanisms. These investments improve the condition, reliability, efficiency, and capability of 

infrastructure to meet mission requirements. The programs plan and execute replacement, installation, 

upgrades, and minor construction projects to revitalize existing facilities or construct new facilities and 

additions.
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6.4.1 Infrastructure Recapitalization Program

The Recapitalization program executes prioritized minor construction and recapitalization investments to 

improve the condition, reliability, efficiency, and capability of infrastructure to meet mission 

requirements. The program plans and executes replacement, installation, upgrades, and minor 

construction projects to revitalize existing facilities or construct new facilities and additions below the 

$30 million minor construction threshold. This investment method is used in conjunction with line-item 

construction to provide timely, appropriately sized, and integrated infrastructure solutions. 

In addition to supporting the enterprise through strategic minor construction investments, the 

Recapitalization Program sustains and modernizes DOE/NNSA infrastructure by improving the state of

obsolete support and safety systems. The program provides funding to revitalize assets that are beyond 

the end of their design life and improve the safety, reliability, and capability of infrastructure to meet 

mission requirements. Recapitalization investments also increase operational efficiencies; reduce risks to

safety, security, environment, and programs; and improve the quality of the workplace. 

Recapitalization Program investments are evaluated and prioritized using an enterprise-wide, risk-based 

assessment of program and safety effects, sustainability, return on investment, and deferred maintenance 

reduction to obtain optimal benefits within the available budget. DOE/NNSA has also incorporated

enhanced project management practices that have increased transparency, reporting accuracy, project 

definition and readiness, and overall program performance.

In FY 2022, DOE/NNSA completed 41 recapitalization projects. This performance reflects the effect of 

advanced planning based on detailed data and the use of the improved reporting tools and processes. 

Several completed projects show DOE/NNSA has directed many infrastructure investments to address

risks identified through facility and mission assessments:

◼ KCNSC – Revitalization of Precision Cleanroom Upgrade, Low Humidity Production Revitalization, 

Assembly and Electrical Fabrication and Machining Revitalization

◼ Y-12 – Elevator Cylinder Replacement

◼ Y-12 – 13.8kV Power Distribution System Conversion Portfolio

◼ NNSS – Frenchman Flat Substation Transformer Replacement

◼ LANL – TA Electrical, Mechanical Revitalization

◼ Pantex – Secondary Electrical Feed Installation

◼ SNL – District Chilled Water System Upgrades

◼ Pantex – Equipment Room Expansion

◼ SNL – Process Oil Storage Tanks Replacement

◼ LANL – Environmental and Vibration Test Facility Fire Suppression Upgrade

◼ SNL – SiFAB UPS System Upgrade, TA-IV District Chilled Water System Upgrades

◼ SNL – Thermal Spray Research Laboratory Facilities' Systems Revitalization

◼ LANL – LANSCE Industrial Controls Replacement

◼ SNL – California Potable Water Distribution System Revitalization TA-IV District Chilled Water 

System Upgrades 

◼ LANL – Safety Systems Two Over One Upgrade

◼ LLNL – Block East Utility Distribution Upgrade
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◼ Pantex – Southwest Circuit Sectional Switches Installation

◼ NNSS – New U1a Powerline Connection to 34.5KVA Distribution Line

◼ LLNL – LEP Building Complex Power Upgrade

◼ NNSS – DAF Operations Complex Power Installation

◼ LANL – PF-4 Public Address System Replacement

◼ LANL – PF-4 Zone 1 Damper Controls and Actuators Safety Upgrades

◼ LLNL – Mechanical Test Capability Consolidation Revitalization

◼ LLNL – Domestic Water and Miscellaneous Valves Replacement

◼ NNSS – Mercury Campus Transportation Upgrades

6.4.1.1 Current Recapitalization Projects

DOE/NNSA currently has over 190 active recapitalization projects. The majority of these projects are 

below $10 million. There are more than a dozen projects ranging between $10–30 million. Projects are 

placed into portfolios, which are used to highlight significant multi-year investment in a common attribute 

or area at a particular site. Below are some examples of DOE/NNSA’s ongoing Recapitalization portfolios 

and projects. 

$10–30 Million Project Examples

◼ LANL – PF-4 Power and Communications Systems Upgrade

◼ LLNL – New Nondestructive Evaluation Building

◼ NNSS – New Mercury Building 

◼ Pantex – New Advanced Fabrication Facility 

◼ SNL – New Explosives Manufacturing Science and Technology Facility 

◼ SNL-California – Limited Area Multi-Program Secure High Bay Laboratory

◼ SNL – New Geosciences Laboratory

◼ NNSS – New Nevada Site Operations Center 

◼ NNSS – New U1a Mission Technical Support Facility (STAR)

◼ LANL – Flight Instrumentation Test Laboratory (Environmental Test Complex) 

◼ LANL – Dual-Axis Radiographic Hydrodynamic Test Vessel Repair Facility & Electrical Circuit 

Upgrades 

◼ LANL – New Fire Station 5 

◼ LLNL – New Joining Capabilities and Vapor Disposition Facility 

◼ LLNL – New Stockpile LEP Office (STAR) 

◼ SNL – New TA-II Master Substation 

Project Portfolio Examples

◼ KCNSC – Mechanical Component Manufacturing Revitalization 

◼ LANL – CMR Initial Projects to Prepare for Closure Portfolio 

◼ LLNL – Applied Materials and Engineering Complex 

◼ NNSS – Mercury Modernization at NNSS

◼ Pantex – Bay and Cell Safety System Upgrades Portfolio
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◼ Pantex – Site-Wide Facility Lightning Protection Upgrade 

◼ SRS – Obsolete Glovebox Oxygen Monitors Replacement Portfolio 

◼ SRS – 234-7H Exhaust Ventilation System Installation 

◼ Y-12 – Fire Water Lateral Replacement Portfolio 

◼ Y-12 – Nuclear Facility Criticality Accident Alarm System Replacement 

6.4.1.2 Recapitalization Program Planning Improvements

DOE/NNSA is improving understanding of long-term programmatic capability and associated capacity 

throughput requirements to better evaluate infrastructure options. Additionally, more front-end 

planning studies are being initiated to ensure that DOE/NNSA can integrate recapitalization planning

across multiple Federal and M&O site organizations, while designing multi-project plans to address 

complex infrastructure challenges. These efforts strengthen DOE/NNSA’s modernization plans by 

ensuring that projects are fully scoped, well -integrated, and executed on time and within budget.

6.4.2 Defense Nuclear Security Minor Construction Investment

The Security Infrastructure Revitalization Program was created by DOE/NNSA’s Office of Defense Nuclear 

Security (DNS) to assure the adequacy of the physical security infrastructure supporting the DOE/NNSA 

mission at the eight sites now and into the future. DNS developed and submitted to Congress the 10-Year 

Physical Security Systems Refresh Plan to outline and guide the scope of the program’s effort. This plan

contains a comprehensive condition assessment of the security infrastructure at each site and a nuclear 

security enterprise-wide prioritized listing of the required upgrades.

The 10-Year Physical Security Systems Refresh Plan identifies and prioritizes security infrastructure 

investments critical to revitalization efforts throughout the nuclear security enterprise. 

DNS minor construction project status for FY 2023:

◼ Device Assembly Facility Vehicle Barrier, NNSS (design FY 2022, estimated completion FY 2028)

◼ Zone 12 Perimeter Intrusion Detection and Assessment System Vehicle Barriers, Pantex (start 

construction FY 2023)

◼ Vehicle Barrier, Y-12 (groundbreaking FY 2022, estimated completion FY 2025)

6.4.3 Site-Directed5 Minor Construction Investments

DOE/NNSA’s contracts with various groups for management and operation of its sites contain 

requirements for M&O partners to plan for and manage DOE/NNSA assets for current and future missions. 

Sites fulfill these responsibilities in part by making minor investments in facilities and infrastructure from 

funds controlled at each site. The sources for these investments can be direct programs (as discussed in 

the previous sections) or indirect funding pools, depending on the nature of the asset and whether the 

site has a multi-mission program portfolio. 

Many DOE/NNSA M&O partners use indirect funding to address high priority needs at each site. On 

multi-mission program sites, indirect funding pools may be created through institutional assessments or 

other similar mechanisms. These pools are used to fund maintenance, utilities, and operations; some 

funding is set aside for site-wide investments. In all cases, spending these funds aligns with accounting 

standards for demonstrating a causal-beneficial relationship, i.e., indirect funds are used for multi-mission 

5 Another term for “site-directed” investments is “indirect-funded” investments.
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program functions and purchases that deliver benefits across programs. M&O partners are also 

responsible for maintaining Weapons Activities capabilities to meet mission needs and often use portions 

of their budgets to fund minor investments in facilities, infrastructure, and equipment to meet those 

responsibilities. 

Examples of indirect expenditures include Institutional General Plant Projects at multi-mission program 

sites, especially the laboratories. These projects are often limited refurbishments of legacy facilities or 

new, moderately sized buildings to accommodate growth at the site and enable prudent space 

management for the institution to maintain facilities in good condition and replace worn-out assets. 

These projects can also provide upgrades/replacements for institutional services such as parking 

structures, cafeterias, or medical facilities.

Site-directed investments over $1 million are reported through the DOE/NNSA Program Management 

Information System, Generation 2 (G2). Providing this information to one centralized system increases 

transparency and coordination for all infrastructure investments (direct and indirect). Capturing the 

details of these projects in G2 ensures that indirect infrastructure investments align with DOE/NNSA’s 

strategic priorities; enhances integration between direct- and indirect-funded infrastructure investments; 

improves reporting to understand total infrastructure recapitalization costs across the enterprise; and 

ensures the capability to prioritize and plan for DOE/NNSA’s long-term stewardship responsibilities.

6.5 Sustainment

This section describes how DOE/NNSA maintains and operates 

existing infrastructure in support of the nuclear security 

mission. DOE/NNSA, in partnership with the M&O partners, 

sustains its assets to enable mission success and readiness; 

ensure operational safety and security; safeguard the 

workforce, public and environment; and meet mission needs 

more efficiently and cost- effectively.

6.5.1 Infrastructure Operations and 

Sustainment

The Operations of Facilities Program under the Infrastructure 

and Operations Program is responsible for operating 

DOE/NNSA facilities in a safe and secure manner and includes essential support such as water and 

electrical utilities, safety systems, lease agreements, and activities associated with Federal, state, and local 

regulations associated with the environment and worker safety and health.

The Maintenance and Repair of Facilities Program provides direct-funded maintenance activities across 

the nuclear security enterprise for the recurring day-to-day work required to sustain and preserve 

DOE/NNSA facilities and equipment in a condition suitable for their designated purpose. These 

sustainment activities are executed through a combination of innovative tools that provide data for risk 

analyses that inform infrastructure management decisions. These decisions dedicate critical resources to 

maintaining facilities already in good condition and repairing the highest risks in DOE/NNSA assets. One 

of these tools is the BUILDER Sustainment Management System, which is a best-in-class, web-based tool 

developed by the U.S. Army Corps of Engineers that provides a consistent, repeatable, quantitative 

method to track and predict the condition of facilities and their systems, components, and 

subcomponents. The DOE/NNSA procured BUILDER in October 2014 and continues to actively implement 

it across its real property infrastructure portfolio with the goal of reaching full program sustainment by 
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the end of FY 2024. To lower the overall cost and ease of using the BUILDER system, DOE/NNSA integrated 

BUILDER with each site’s local Computerized Maintenance Management Systems, which track daily 

maintenance activities, document replacement of components, and offer a variety of features such as 

preventive maintenance scheduling, warranty management, and space planning. These features help 

sites maintain effective and streamlined operations. Moving forward, DOE/NNSA will continue leveraging 

BUILDER’s data-driven, risk-informed metrics to inform infrastructure renewal decisions and ensure the 

greatest return on investment. 

Maintenance and repair activities sustain an acceptable condition of real property assets to perform their 

designated purpose or to mitigate risks posed by excess assets until their disposition. These efforts 

support the recurring daily work needed to sustain plant, property, assets, systems, roads, and 

infrastructure equipment in a condition suitable for its designated purpose. Efforts include required 

maintenance through surveillance and predictive, preventive, and corrective maintenance activities to 

maintain facilities, property, assets, systems, roads, equipment, and vital safety systems. Maintenance 

funding can be used for sustainment efforts or to respond to unexpected/urgent issues that require 

immediate correction to ensure safe, compliant, and reliable operations.

Deferred maintenance is defined as any maintenance activities that were not performed when they 

should have been or were scheduled. As a result, they are rolled over as a continued expected expense 

to subsequent fiscal years until the maintenance can be completed. Repair needs are the repairs required 

to ensure that a constructed asset is restored to a condition that is substantially equivalent to the most 

recently configured designed capacity, efficiency, or capability.

In FY 2019, DOE/NNSA began its transition to BUILDER data to determine total deferred maintenance and 

repair needs. Importantly, this transition to a standardized, structure-based approach provides 

DOE/NNSA with increased transparency and deferred maintenance data accuracy across the enterprise. 

In FY 2020, DOE/NNSA conducted an in-depth analysis of FY 2019 calculations and implemented a few 

minor enhancements to ensure a more accurate reflection of the true condition of DOE/NNSA’s 

infrastructure. This along with regular degradation and increased supply chain issues resulted in

DOE/NNSA’s deferred maintenance backlog increasing from $6.07 billion in FY 2021 to $6.48 billion in 

FY 2022.

Revitalizing DOE/NNSA infrastructure requires grappling with a $131 billion enterprise in which more than 

half of DOE/NNSA facilities are in insufficient condition to serve mission needs (e.g., poor or very poor 

condition). Addressing this legacy while building for the future requires significant, sustained, and timely 

funding; robust planning and execution; and close collaboration across all stakeholders. DOE/NNSA 

remains committed to continuous improvement of management practices and transparency in 

stewarding taxpayer resources while working to modernize the nation’s nuclear infrastructure.

DOE/NNSA’s asset management programs use supply chain management strategies to increase quality, 

enhance buying power, and accelerate the delivery for repairing and replacing major common building 

systems. These efforts are particularly important during a period of increasing costs for building materials

and long-lead equipment procurement delays. Since FY 2015 the Roof Asset Management Program has 

reduced the number of DOE/NNSA roofs rated as failed from 18 to 9 percent. Building on the program’s 

successes, the Cooling & Heating Asset Management Program was established in FY 2017, completing 24 

projects since inception. During FY 2021, there were active Cooling & Heating Asset Management 

Program projects at every site.
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6.5.2 Programmatic Facility Sustainment

In some instances, the nature of core mission areas leads to direct programmatic sustainment funding for 

certain operations. For example, the SRT&E Program is responsible for the HPC capabilities needed for 

stockpile stewardship in modeling, simulation, and experiments conducted at various facilities and 

experimental capabilities such as inertial confinement fusion. Within SRT&E, operational costs at facilities 

are directly supported and budgeted within the Inertial Confinement Fusion (ICF) and Advanced 

Simulation and Computing (ASC) Programs. The ICF Facility Operations and Target Production subprogram 

supports efficient operations at NIF, Omega Laser Facility (Omega), Z, and the Trident and NIKE facilities 

(see Chapter 4, Section 4.3.3, for more information on NIF, Z, and Omega). Similarly, the ASC Facility 

Operations and User Support subprogram provides the facilities and services required to execute nuclear 

weapon simulations. Facility Operations include physical space, power, and other utility infrastructure; 

local area/wide area networking for local and remote access; and system administration, cybersecurity, 

and operations services for ongoing support. 

Programmatic operations must provide for the safety and health of workers and the protection of the 

environment, regardless of the funding source. As part of DOE/NNSA’s efforts for a more sustainable 

enterprise, Z was awarded an environmental management award of excellence for significantly reducing 

emissions of the powerful greenhouse gas, sulfur hexafluoride. 

ASC is the primary user and chief programmatic advocate 

for the facilities and services required to run nuclear 

weapons simulations and operate Commodity Technology 

and Advanced Technology systems. Each laboratory’s 

computing capability comprises not only HPC systems, but 

also ancillary physical components such as space, power, 

storage, file systems, local area/wide area networking for 

local and remote access, and a host of system 

administration, cybersecurity, and operations services for 

ongoing support of HPC system and support equipment. 

There are also specific user services associated with items 

such as a computer center hotline and help-desk services, 

account management, web-based system documentation, 

system status information tools, user training, troubleticketing systems, common computing environment, and application analyst support that are included in 

the fiduciary responsibilities of the program. Therefore, each center’s footprint can physically span 

multiple buildings.

ASC manages the costs associated with each laboratory’s current computing centers and considers 

multi-year budget planning to deliver future systems based on programmatic need. The funding 

necessary to operate and modify the computing centers comes from a combination of direct 

programmatic funding from the ASC and other DOE/NNSA programs, which may use the same buildings, 

or indirect overhead charges brought in by the laboratories directly. Within Weapons Activities, the

Infrastructure and Operations Program provides capabilities and infrastructure for the nuclear security 

enterprise but is not responsible for maintenance and operations of the ASC computing centers

themselves.

Sulfur hexafluoride reclaiming system being used 

on SNL’s Z 
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6.5.3 Site-Directed Sustainment Investments

At multi-program sites, indirect pools may be created to pay for maintenance and operations. These funds 

are then used to pay utility bills; provide preventive, predictive, and corrective maintenance to facilities 

and equipment; and replace equipment associated with facilities and infrastructure. These funds may 

also cover various site-wide services. Site-directed investments are reported through G2. Providing this 

information to one centralized system increases transparency and coordination for all infrastructure 

investments (direct and indirect). Capturing the details of these investments in G2 ensures that indirect 

infrastructure investments align with DOE/NNSA’s strategic priorities; enhances integration between 

direct- and indirect-funded infrastructure investments; improves reporting to understand total 

infrastructure recapitalization costs across the enterprise; and ensures the capability to prioritize and plan 

for DOE/NNSA’s long-term stewardship responsibilities.

6.6 Disposition of Excess Facilities 

DOE/NNSA infrastructure that is no longer needed must be 

dispositioned to minimize risks to workers, the public, the 

environment, and the mission. Approximately 8 percent of 

assets located on DOE/NNSA’s sites are designated as excess.

This number has decreased 1 percent in the past year, and a 4

percent reduction since 2018, resulting in reduced risk to 

DOE/NNSA overall. DOE/NNSA’s highest disposition priorities 

are to stabilize degraded facilities, characterize hazards and 

conditions, remove hazardous and flammable materials, and 

place facilities in the lowest acceptable risk condition possible 

until they can be dispositioned. DOE/NNSA’s area plans 

outline the details of how DOE/NNSA plans to address these 

excess facilities.

Several recently completed projects demonstrate that 

DOE/NNSA has directed infrastructure investments to address risks identified through facility and mission 

assessments:

◼ Demolition of 17 process contaminated facilities at LANL including HE Buildings 16-0460 and 

16-0306 and 15 magazines

◼ Removal of Building 9404-18 and demineralized water tanks at Y-12 

◼ Advanced planning and field work performed in support of the utility reroute scope associated 

with DOE Office of Environmental Management disposition activities in preparation for the 

demolition of the large process contaminated excess facilities at Y-12.

The longer an unused facility is left standing before demolition, the more it deteriorates, and the more 

difficult it is to maintain in a safe shutdown condition. Aging facilities can pose risks to human health, the 

environment, and the mission. DOE/NNSA is committed to mitigating these risks by dispositioning excess 

facilities as quickly as possible and working with the DOE Office of Environmental Management when its

expertise is required.

During the next 10 years, over 800 additional assets with $4.3 million gross square feet are planned to 

become excess on DOE/NNSA sites. Of these assets, approximately 40 percent are process contaminated 

and may require DOE Office of Environmental Management expertise to demolish.
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6.7 Modernization of Programmatic Equipment

Facilities and infrastructure are just one of the three aspects of sustainment that must be managed in 

support of the mission; equipment and people are also critical to mission performance. The workforce 

aspects are discussed in Chapter 7. This section focuses on the equipment aspects of sustainment. 

DOE/NNSA manages and funds equipment procurement across the nuclear security enterprise through 

multiple programs such as stockpile modernization programs or the Engineering Program. These 

programs selectively fund mission-related equipment procurement to meet their schedule or new 

requirements. In addition to these, several other programs maintain nuclear security enterprise 

capabilities through equipment refurbishment and replacement. Those programs include 

Capabilities-Based Investments (CBI), Production Operations, and Non-Nuclear Component 

Modernization. Furthermore, the organization that initially funds procurement of a piece of equipment 

will most likely not be the only organization benefiting from the acquisition in the future, which adds 

complexity to the task maintaining and replacing equipment. 

While each program focuses on its own respective responsibilities and requirements, the integrated 

nature of nuclear weapons work creates natural mission overlap across programs. In these cases, the 

Programmatic Recapitalization Working Group works with the M&O sites to capture the current inventory 

of capital equipment items as well as future needs across the Future Years Nuclear Security Program to 

allow DOE/NNSA to better plan and program capital equipment needs amongst the appropriate funding 

program offices. This allows better alignment of planning and programming activities across relevant 

DOE/NNSA programs. 

Equipment modernization, replacement, and refurbishment planning will enable DOE/NNSA to 

recapitalize the nuclear security enterprise’s infrastructure and provide an effective, responsive, and 

resilient nuclear weapons infrastructure. It is also crucial to the maintenance of the nuclear security 

enterprise’s current capability. The investment strategies described in the following sections presents a 

variety of programs focused on investing in programmatic equipment, as well as certain equipmentrelated sustainment activities funded by Infrastructure and Operations. Together, they provide the 

baseline activities essential to maintaining a functional and efficient nuclear security enterprise.

6.7.1 Programmatic Equipment Investments

Equipment investments by mission-specific programs are dictated by programmatic need.

For the weapons programs (e.g., Stockpile Major Modernization and Stockpile Sustainment), equipment 

purchased might include radiography machines, mass spectrometers, shaker tables, blast tubes, 

centrifuges for qualification, certification, and surveillance activities that are specific to a weapon system. 

A weapon program might also require specific capabilities in production equipment, such as specialized 

mills and lathes, to produce component designs and would cover these costs, as the requirements for that 

equipment would be tied directly to their program. For example, the W80-4 LEP has funded programmatic 

equipment such, as the digitizers needed for hydro shot diagnostics, a computer numerical controlled mill 

and lathe for HE and radiological materials to meet integrated weapon experiment deliverables, and 

inspection equipment to validate that machines’ experimental components meet weapon engineerspecified requirements.

Weapon programs also invest in equipment and infrastructure necessary to maintain their schedule. 

Often these investments are split among weapon programs that could benefit from such procurements in 

the future. For instance, the W88 Alteration 370 benefited from investments made by the W76 and 
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B61-12 LEPs. Where multiple stockpile modernization programs can benefit, CBI (described in Chapter 3) 

is also a major source of funding. 

SRT&E investments cover a range of highly specialized and common equipment that is essential to the 

high-tech work of stockpile stewardship. SRT&E equipment might provide or facilitate environments for 

testing and experimentation, produce data from those experiments, or help synthesize the data from the 

experiments to inform research, design, production, qualification, and surveillance activities across 

multiple different weapon systems and programs. Examples include next generation computing 

platforms, diagnostic equipment tied to subcritical and hydrodynamic experiments, and accelerators 

associated with advanced radiography. Given the specialized nature of these types of equipment, 

investments can be quite costly. New equipment is procured by SRT&E programs as mission needs arise, 

equipment becomes technologically obsolete, emerging technologies demand investment in new 

capabilities, or new facilities or capabilities come online. In addition, as urgent needs arise, CBI and 

Non-Nuclear Component Modernization makes investments in equipment for SRT&E missions that are 

tied to LEP schedules.

The Additive Manufacturing and Component Manufacturing Development programs make equipment 

investments aimed at validating production and qualification processes that are vital to the future 

stockpile, with a long-term goal of reducing required production floor space and attendant infrastructure. 

While these programs may purchase one to two pieces of equipment with advanced capabilities, the 

weapon programs, CBI, or appropriate modernization offices would be expected to purchase the 

remaining equipment needed to realize the Additive Manufacturing and Component Manufacturing 

Development-provided capability at full production scale. In some cases, the initial investment by these 

programs could fulfill production requirements, and the responsibility for the operations and 

maintenance of that equipment would transfer to the appropriate program, such as Production 

Operations. Examples of equipment procured through these programs include a variety of additive 

manufacturing machines, advanced testers, and other supporting equipment.

6.7.2 Site-Directed Equipment Investments

As with facilities and infrastructure, sites may make investments in equipment for activities that support 

weapons and other site missions (multi-program), and these investments may either be made using direct 

funds or include indirect cost pools. The cost of programmatic equipment that supports multiple 

programs should be allocated to those programs in accordance with the benefits received.

6.8 Leveraging Weapons Activities Investments Across 

DOE/NNSA

Several other DOE/NNSA programs (e.g., NNSA’s Offices of Defense Nuclear Nonproliferation, 

Counterterrorism and Counterproliferation, and Emergency Management) rely on infrastructure funded 

by Weapons Activities and other DOE program offices. 

6.8.1 Support of Nonproliferation Efforts

The Office of Defense Nuclear Nonproliferation’s Office of Global Material Security relies on infrastructure 

maintained by other DOE/NNSA offices, as summarized below.

◼ SNL and LANL conduct nuclear security training and non-destructive assay technique training for 

the International Atomic Energy Agency and bilateral partners.
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◼ The DOE/NNSA National Training Center in Albuquerque, New Mexico, will provide bilateral 

partners with Protective Force training on a limited basis.

◼ The Alarm Response Training facility will transition to the Oak Ridge Enhanced Technology and 

Training Campus in FY 2023. The program conducts radiological security training for domestic and 

international security forces, health and safety personnel, and local law enforcement to 

effectively respond to the theft of radioactive sources.

◼ SNL and LANL provide technical expertise, testing equipment, and SNM sources that are critical in 

the evaluation and characterization of commercial detection equipment.

The Office of Defense Nuclear Nonproliferation R&D relies on supportive capabilities at several 

laboratories, plants, and sites that enable mission-relevant R&D activities, as summarized below.

◼ NNSS hosts several experimental and applied test beds to demonstrate next-generation 

nonproliferation technologies for detecting foreign nuclear weapons development activities, 

which will result in new capabilities at the national security laboratories.

◼ The Device Assembly Facility at NNSS hosts and facilitates detection experiments for university 

and laboratory projects.

◼ SNL, LANL, LLNL, and NNSS provide critical expertise and infrastructure to support multiple

weapons-related experimental campaigns, including U1a and Big Explosives Experimental Facility.

◼ The Microsystems Engineering, Sciences, and Applications Complex at SNL provides resources to 

develop beyond leading-edge trusted microsystems technologies that enable space-based 

detonation detection capabilities.

◼ SNM irradiation experiments are conducted at the National Criticality Experiments Research 

Center at NNSS, where criticality assembly machines provide the capability for research to 

improve precision measurements of nuclear fission product yields and other nuclear data 

parameters.

◼ HPC capabilities are used for a broad range of modeling and simulation research across multiple 

research areas at SNL, LANL, and LLNL.

The Office of Defense Nuclear Nonproliferation’s Office of Material Management and Minimization (M3) 

relies heavily on the infrastructure maintained by other DOE/NNSA offices. Effects of the aging 

infrastructure on the implementation of key nonproliferation programs are summarized below.

◼ Conversion Program

– Y-12’s uranium facilities perform downblending and casting activities that produce 

low-enriched uranium (LEU) material that is supplied to research reactors and medical isotope 

producers domestically and internationally and is used to produce LEU-molybdenum material 

that will allow conversion of the U.S. high-performance research reactors from highly 

enriched uranium (HEU) to LEU. Aging casting furnaces at Y-12 are a programmatic risk to 

production of future LEU material. In the future, M3 plans to shift to using BWX Technologies, 

Inc. (BWXT) for its alloy casting capability instead of Y-12. This shift is planned to begin in 

FY 2025 and fully transition by FY 2028. In the meantime, Y-12 alloy production will be 

required until BWXT proves fully capable. M3 will still rely on Y-12 for production of LEU for 

research reactors and medical isotope producers.

– Plant and personnel challenges at the Analytical Chemistry Organization pose major 

programmatic risks to LEU production, USHPRR conversion efforts, and M3’s LEU scrap 
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recovery project. The Analytical Chemistry Organization analyzes samples to ensure that 

9212’s LEU castings meet the Y-12 Standard Specification, which is relied upon by all 

purchasers of Y-12 LEU. M3 also relies on the laboratory for sample analysis of LEU scrap 

material planned for shipment to BWXT to ensure the material conforms with BWXT’s facility 

limits.

– The Sigma facility at LANL develops and optimizes LEU-Mo fuel fabrication processes. 

◼ Material Disposition Program

– TA-55 PF-4 at LANL disassembles nuclear weapon pits and converts the resulting plutonium 

metal into an oxide form using the Advanced Recovery and Integrated Extraction System. 

While this is an Office of Defense Nuclear Nonproliferation program, this equipment set is 

also used to support pit surveillance and other Office of Defense Programs activities.

– The K Area Complex at SRS stores surplus plutonium that will be dispositioned. The K Area 

Complex is a DOE Environmental Management facility; however, DOE/NNSA plans to install 

equipment for the Surplus Plutonium Disposition Program under the dilute and dispose 

strategy and completed construction of a transuranic waste storage pad and loading 

capability for shipping diluted plutonium oxide to the Waste Isolation Pilot Plant.

– Under the dilute and dispose strategy, the Waste Isolation Pilot Plant is the permanent 

disposal site for diluted plutonium oxide, along with waste generated by Office of Defense 

Programs and other nonproliferation activities.

– The Material Disposition program relies on resources, facilities, and support from Pantex and 

KCNSC to support the dilute and dispose strategy.

– DOE/NNSA’s Secure Transportation Asset Program will provide resources to ship Security 

Category I quantities of SNM within the nuclear security enterprise in support of the Surplus 

Plutonium Disposition Program under the dilute and dispose strategy.

– The H-Canyon at SRS will be used to disposition portions of the plutonium inventory returned 

to the United States through the Nuclear Material Removal Program. The Savannah River 

National Laboratory provides R&D and implements technical solutions for a variety of 

material disposition activities.

– Enriched uranium operations at Y-12 allow analysis, processing, and packaging of materials to 

be downblended or properly disposed. The Material Disposition program also provides 

inventories of HEU for research reactor and other uses. The Material Disposition program 

recognizes the same risks listed by the Conversion Program above. Additionally, completing 

Material Disposition work at Y-12 is heavily leveraged in the low-equity discards work, which 

relies on the waste management infrastructure managed by Office of Defense Programs at 

Y-12, as well as disposal sites.

◼ Nuclear Material Removal Program

– DOE/NNSA’s Secure Transportation Asset Program provides resources for multiple material 

removal campaigns. The DOE/NNSA Office of Secure Transportation facilitates these projects 

by providing safe and secure transport of nuclear material within the territory of the 

United States.

– The L-Reactor basin at SRS, a DOE Environmental Management facility, receives enriched 

uranium from the Removal Program and stores the material pending disposition.
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– The K Area Material Storage facility receives enriched uranium and plutonium from the 

Removal Program and stores the material pending disposition.

– Savannah River National Laboratory operates the Mobile Plutonium Facility in support of 

international removal activities and provides other critical support to the Removal Program.

– Oak Ridge National Laboratory (supported by Y-12) operates the Mobile Uranium Facility in 

support of international removal activities and provides other critical support to the Removal 

Program.

– The HEU Materials Facility at Y-12 receives enriched uranium from the Removal Program and 

stores the material pending downblending and disposition.

The Office of Defense Nuclear Nonproliferation’s Office of Nonproliferation and Arms Control (NPAC) also 

relies on the infrastructure maintained by other DOE/NNSA offices, as summarized below.

◼ NPAC relies on the availability of Category I, II, and III SNM standards and sealed sources for 

detector and system development, as well as facilities for testing prototype radiation detection 

monitoring and safeguards equipment and for training U.S. personnel in equipment use and 

foreign partner personnel in the fundamentals of safeguards and material measurement. While 

the health of the facility and SNM infrastructure remains sufficient at this time, downsizing over 

the last decade has required programs to use less Category I and II materials and more Category III 

and IV materials for detector development and training. As DOE/NNSA recapitalizes facilities that 

are critical to the NPAC mission, Defense Nuclear Nonproliferation offices will work with the 

appropriate program managers to ensure NPAC goals are incorporated as resources allow.

◼ DOE/NNSA infrastructure at all sites ensures NPAC can develop and maintain a U.S. capability to 

perform on-site verification and monitoring activities at nuclear material production and 

processing facilities and nuclear explosive testing sites. NPAC uses the DOE/NSNA infrastructure 

to train U.S. personnel, to develop and validate deployable verification equipment, and to refine 

on-site verification and monitoring approaches.

◼ At Pantex and Y-12, NPAC relies on facilities and operational expertise to test warhead monitoring 

and verification capabilities, and to assess the feasibility of equipment deployment at weapons 

facilities. Demonstrations and evaluations at operational nuclear weapons facilities are essential 

for developing potential long-term solutions to the technical challenges of verifying nuclear 

weapon reductions. They support the United States’ ability to engage technically with partner 

countries under initiatives such as the International Partnership for Nuclear Disarmament 

Verification. 

◼ NPAC relies on access to nuclear weapons design information and access to weapons activities 

subject matter experts to help evaluate potential nuclear warhead monitoring and verification 

capabilities and ensure U.S. weapons design information will be protected as part of any future 

monitoring initiative.

◼ NPAC and various U.S. agencies work with DOE/NNSA Defense Programs to support transparency 

initiatives in fulfilling the Nation’s Article VI commitments under the Nuclear Non-Proliferation 

Treaty.

◼ NPAC uses KCNSC, LANL, LLNL, SNL, and NNSS to conduct seminars on proliferation-sensitive 

commodities and technologies, particularly those subject to export controls and related to nuclear 

weapons and associated delivery systems. These seminars and workshops provide the U.S. 

agencies with knowledge of these commodities and emerging technologies that is not available 
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elsewhere. Participants can apply what they learn in their jobs in nonproliferation policy, export 

licensing, export enforcement, and other functions related to preventing weapons of mass 

destruction proliferation.

6.8.2 Support of Counterterrorism and Counterproliferation and 

Emergency Operations Efforts 

The Office of Counterterrorism and Counterproliferation (CTCP) heavily leverages infrastructure that is 

primarily used for stockpile stewardship. These assets ensure CTCP can execute its missions to counter 

nuclear threats, respond to nuclear incidents and accidents, and deliver an emergency response and 

consequence management capability for the U.S. Government. CTCP is further able to harness these 

resources to inform U.S. Government policies and deliver nuclear and radiological emergency 

preparedness training for the U.S. Government and its foreign partners. From the outset of Russia’s 

full-scale invasion of Ukraine, CTCP has been heavily involved in the crisis, providing technical advice to 

U.S. Government decision-makers and Ukrainian partners. In particular, CTCP has relied on infrastructure 

assets to model and plan for a wide range of potential nuclear emergencies ranging from nuclear power 

plant accidents to Russia’s use of nuclear weapons; such contingency planning would inform life-saving 

responses to nuclear events in Ukraine and beyond.

◼ Nuclear Threat Science Program

– LANL, LLNL, and SNL support the Nuclear Threat Science Program by maintaining and 

advancing the U.S. Government’s ability to assess potential nuclear threat devices, including 

improvised nuclear devices or foreign nuclear devices out of state control. CTCP leverages 

DOE/NNSA infrastructure, originally developed for stockpile stewardship, to enable 

computational assessment of nuclear threat devices by expanding the HPC code capabilities. 

This understanding of nuclear threat devices is used to inform broader U.S. Government 

material security, nuclear incident response, and international nuclear threat reduction 

efforts.

– CTCP conducts experiments at all DOE/NNSA national security laboratories and several DOE 

Office of Science laboratories for the refinement and validation of predictive models. 

– To understand materials not traditionally studied by the U.S. stockpile, LLNL, LANL, and SNL 

execute foundational science programs to characterize nuclear materials and explosives on 

similar platforms. For example, CTCP uses diamond anvil cell facilities, gas guns, and other 

high-pressure facilities to evaluate nuclear materials. Specific unique facilities supporting 

stockpile stewardship are also used to improve assessment activities, including TA-55 and 

proton radiography at LANL, Joint Actinide Shock Physics Experiment Research gas gun and 

High Explosives Applications Facility at LLNL, and Z at SNL. These activities are informed by 

foundational science that yields a broad understanding of nuclear material behavior. Data 

from these experiments are used to improve material models, then used in computational 

codes, which are used across DOE/NNSA programs.

– LANL, LLNL, and SNL support the development and validation of predictive modeling in 

support of nuclear incident response, as well as training to the interagency weapons of mass 

destruction defeat community. Facilities such as the Dual-Axis Radiographic Hydrodynamic 

Test at LANL, the Site 300 Global Security Campus Facility (Building 850), Contained Firing 

Facility at LLNL, as well as multiple explosives testing sites across LANL, LLNL, and SNL, support 

CTCP experimental validation efforts.
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– In cooperation with LANL, LLNL, and SNL, NNSS provides unique facilities and infrastructure 

to support Nuclear Threat Science experimental validation efforts. Capabilities at NNSS allow 

experimental efforts on hazardous materials or at threat-representative scale.

◼ Nuclear Forensics Program

– Technical nuclear forensics performance depends on the core capabilities developed during 

the U.S. nuclear weapons development and testing program. Weapons design expertise and 

the simulation tools, manufacturing base, and experimental capabilities required for 

Weapons Activities provide a strong foundation for the technical nuclear forensics mission. 

Weapons Activities supports much of the expertise, facilities, nuclear material handling 

infrastructure, and historic knowledge necessary to perform technical nuclear forensics, 

including the National Nuclear Materials Archive. DOE/NNSA’s Secure Transportation Asset 

provides safe and secure transportation of nuclear material in the United States and supports 

the CTCP response teams. The technical nuclear forensics mission also relies on DOE’s 

broader ST&E capabilities, including laboratories maintained by DOE’s Offices of Science and 

Nuclear Energy.

◼ Nuclear Incident Response Program

– CTCP provides operational support, training, and equipment for major public events and 

emergencies, both foreign and domestic. CTCP draws upon these activities to aid in the 

development of effective public policies, medical procedures, and tabletop and field exercises 

that guarantee a robust multilateral incident preparedness and response for countering 

nuclear and radiological incidents, accidents, and terror threats.

– CTCP relies on a diverse base of rapidly deployable assets, including specialized facilities, 

vehicles, and equipment to support the Nuclear Emergency Support Team (NEST) Technical 

Reachback and training to build international capacity, as well as the U.S. Government’s

effective response to a nuclear or radiological incident or emergency. These assets include 

the Radiological Assistance Program, based at 12 DOE locations around the Nation; the Aerial 

Measuring System stationed at the Remote Sensing Laboratories at Joint Base Andrews 

(Washington, DC) and Nellis Air Force Base (Las Vegas, Nevada); the National Atmospheric 

Release Advisory Center at LLNL; the Nuclear Response Group Readiness Operations Center 

located on Kirtland Air Force Base; and the Radiation Emergency Assistance Center/Training 

Site at the Oak Ridge Institute for Science and Education in Oak Ridge, Tennessee. The NEST

Technical Reachback Home Teams are a virtually connected capability that has static nodes 

located at and operated by LANL, LLNL, SNL, Pantex, and both Remote Sensing Laboratory 

locations. When activated, Home Teams provide the necessary remote technical assistance 

to the deployed NEST assets as well as their interagency partners from the Federal Bureau of 

Investigation, the Department of Defense, Department of Homeland Security, and other 

Federal, state, and local agencies. The Nuclear Incident Team at DOE Headquarters Forrestal 

building and its alternate location at the DOE facility in Germantown, Maryland, also receives 

remote technical assistance via Home Teams. The NEST relies heavily on expertise built across 

the Laboratories, specifically the nuclear weapons programs, to ensure superior knowledge 

of nuclear weapons designs, effects of incidents or accidents on safety, and hazards 

associated with radiological and nuclear material. Stockpile stewardship activities for 

surveillance, testing, evaluation, modeling, and simulation of these scenarios is critical to the 

success of the Nuclear Incident Response Program.
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◼ Nuclear Incident Policy and Cooperation Program

– CTCP builds partnerships and capabilities for security, preparedness, and response against 

radiological and nuclear threats. CTCP strengthens domestic and international capabilities for 

radiological and nuclear incident, accident, and terrorism preparedness and response, and to 

increase awareness about the nuclear and radiological terrorism threat.

– CTCP, in cooperation with NNSS, Idaho National Laboratory and LLNL, provides unique 

facilities and infrastructure to support capacity building training, workshops, and conferences. 

Capabilities at NNSS and Idaho National Laboratory allow for realistic training on actual 

radioactive contamination using ground and aerial assets.
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Chapter 7

Workforce

The Department of Energy’s National Nuclear Security Administration (DOE/NNSA) workforce1is the 

nuclear security enterprise’s most critical asset. DOE/NNSA’s ability to meet all its nuclear security 

missions requires a unique, diverse, and highly skilled workforce with expertise across a broad range of 

disciplines. DOE/NNSA and its management and operating 

(M&O) partners are working diligently to recruit and retain the 

workforce essential to meeting the enduring national security 

missions that face growing demand from weapons and physical 

infrastructure modernization programs and from emerging 

needs. Retention is critical since some of the required skills 

cannot be learned in the classroom and are not directly 

transferable from other industries. Just as DOE/NNSA is 

modernizing the stockpile and its infrastructure, it is also working 

to modernize its approach to the workforce. 

Competition for skilled workers across multiple disciplines and 

job categories increased over the last 2 years due to a changing 

national job landscape, and DOE/NNSA is actively working to hire and retain personnel. For example, in 

2022, DOE/NNSA’s M&O contractors experienced an increase in attrition rates above historical norms, 

which drove increased hiring. NNSA authorized multiple actions related to compensation and benefits to 

help curb the rising attrition, and 2023 attrition rates are returning to historically normal levels. Despite 

challenges, DOE/NNSA laboratories, plants, and sites succeeded in on-boarding and integrating large 

numbers of new workers while maintaining productivity and meeting safety and security requirements. 

They now must build on this hiring success by retaining workers, which is critical in roles that require years 

of training.

Over the past 2 years, M&Os, in collaboration with DOE/NNSA, implemented two major initiatives to 

enhance retention and transfer knowledge from experienced staff to newer employees or those who have 

taken new roles within the enterprise. First, flexible work schedules and locations have been 

implemented at a majority of sites. These initiatives were initially started to mitigate Coronavirus Disease 

2019 risks but will likely remain in place for positions whose responsibilities allow for remote work or 

hybrid schedules. Flexible work schedules are an attraction and retention tool for the workforce. 

DOE/NNSA continues to innovate its approach to workforce management to meet the challenge of

maintaining a highly skilled population across all capabilities and locations. Second, engagement with 

students and early-career science, technology, engineering, and math (STEM) employees exposes them 

to the unique mission of DOE/NNSA and the variety of opportunities available within the nuclear security 

enterprise. DOE/NNSA recently moved Academic Programs from a subprogram of the Office of Defense 

Programs’ Stockpile Research, Technology, and Engineering program to an integrated program in the 

Office of the Chief Science and Technology Officer, demonstrating its commitment to investing in scientific 

research and developing a pipeline of talented individuals who can contribute to the nuclear security 

enterprise of the future. M&Os engage in numerous academic collaborations to introduce young talent 

1 This workforce discussion primarily speaks for the Weapons Activities account.

Workforce Snapshot (Enterprise-Wide)

(October 1, 2021–September 30, 2022)

• Total Headcount: 57,498

• Average Age: 44.6

• Average Years of Service: 10.2

• Retirement-Eligible Population: 21.6%

• Hires: 8,260

• Separations: 5,592

• Net Change: 2,668
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to the nuclear security enterprise and to leverage academia to advance the science and technology that 

underpins science-based stockpile stewardship. Each M&O laboratory, plant, and site has strong student, 

postdoctoral, and vocational training, as well as early career engagement to attract future workers.

Additionally, DOE/NNSA’s senior leadership is committed to advancing diversity, equity, inclusion, and 

accessibility throughout the Federal workforce. In September 2022, DOE published its first-ever Diversity, 

Equity, Inclusion, and Accessibility Strategic Plan, which outlines actions to strengthen the department’s

efforts to recruit, hire, develop, promote, and retain the Nation’s talent; remove inequitable barriers to 

career and advancement opportunities; and build and sustain an inclusive and accessible work 

environment. The plan answers the call issued by President Biden in Executive Order 14035, Advancing 

Diversity, Equity, Inclusion, and Accountability Within the Federal Government, that directs all Federal 

agencies to provide a roadmap to ensuring the Federal workforce reflects the full diversity of the American 

people and ensure that public servants at all levels have an equal opportunity to succeed and lead. 

This chapter provides an overview of the composition, status, demographics, and accomplishments of the 

workforce. It covers challenges and strategies used to address those challenges. Appendix F, “Workforce 

and Site-Specific Information,” covers the missions, capabilities, and workforce data for each of the eight 

nuclear security enterprise laboratories, plants, and sites as well as the Federal workforce.

In collaboration with M&Os, DOE/NNSA expanded workforce 

data collection to include regular, limited term, and protective 

force employees in an effort to better capture information on 

all types of personnel who support DOE/NNSA’s mission. 

Additionally, students and interns are now counted throughout 

the year to better describe the national security enterprise’s 

early engagement with students. These students are not 

included in the charts and statistics shown throughout this 

chapter; they are instead shown in callout boxes and in 

Appendix F. All charts and statistics in this chapter rely on 

workforce data as of September 30, 2022.

7.1 Workforce Composition

DOE/NNSA’s workforce has three components: the Federal 

workforce, the eight M&O-operated sites,2and a wide variety 

of non-M&O entities that provide support to DOE/NNSA’s 

missions. 

7.1.1 Federal Workforce

The Federal workforce is situated at DOE/NNSA Headquarters 

in Washington, DC; Germantown, Maryland; and Albuquerque, 

New Mexico, as well as field offices located across the nuclear 

security enterprise.

The Federal workforce is responsible for program and project 

management, as well as Federal contractor assurance and 

oversight of the national security missions across the 

enterprise. They are responsible for performing inherently 

2 M&Os are consortia of industrial and academic contractors. More detail on these contractors may be found in Appendix F.

A Collaborative Workforce

DOE/NNSA’s workforce consists of three 

essential integrated components, forming one 

team:

• The Federal workforce leads planning, 

programming, budget formulation (and 

execution), and evaluation activities for 

DOE/NNSA’s national security programs 

and provides other supporting roles. It 

provides strategy, direction, and priorities to 

accomplish the mission the sites implement.

• The M&Os perform the full spectrum of 

technical activities in support of 

DOE/NNSA’s nuclear security missions 

while the Federal workforce provides 

oversight. The M&Os and Federal 

workforces collaborate to develop and 

implement strategic planning for the nuclear 

security enterprise. 

• Non‐M&Os enable mission success by 

providing materials, components, and 

specialized services; access to 

supplemental experimental assets; and use 

of academia’s R&D resources.

Personnel exchange and embedding 

programs foster deeper understanding of 

partner roles and mission critical contributions 

while strengthening communication lines 

within and between partner organizations.
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governmental functions3such as planning, programming, and budgeting activities; fiduciary oversight; risk

prioritization product acceptance; supply chain management; legal; human resources; acquisition; and 

environmental, safety, and health oversight duties. This workforce comprises highly educated and 

experienced civil servants from a variety of backgrounds.

As of September 30, 2022, DOE/NNSA’s Federal workforce had a headcount of 2,421 employees. This 

number does not include DOE-funded Federal personnel within the Office of Naval Reactors, but does 

contain Federal staff within the Office of Secure Transportation, as discussed in Chapter 5. Of the 2,421

employees, approximately 1,200 are directly working on, or playing a supporting role in, the Weapons 

Activities programs discussed throughout this plan. The rest are involved in areas such as Defense Nuclear 

Nonproliferation, Counterterrorism and Counterproliferation, Management and Budget, General Counsel, 

Public Affairs, Congressional and Intergovernmental Affairs, Field Offices, and others. The Federal 

workforce tends to skew heavily towards the general management labor category, although engineers 

and physicists are represented as well.

The average age of the Federal workforce is 47 years old, with approximately 15 percent eligible for 

retirement. The average employee has 14.5 years of service. Attritions increased from the historical trend 

of about 8 percent to 10.4 percent in fiscal year (FY) 2021 and 11.8 percent in FY 2022;4 however, hiring 

has resulted in a slight increase in the total number of Federal employees. Projected needs will increase 

gradually over the next 5 years, topping out at a headcount of 2,671.

7.1.2 Management and Operating Workforce

The M&O workforce is situated at the eight government-owned or -leased nuclear security enterprise 

laboratories, plants, and sites discussed in Chapter 1, Section 1.2, of this report and depicted in 

Figure 7–1. These partners each bring unique capabilities to the nuclear security enterprise. Each 

specializes in certain areas–for instance, weapon design, warhead assembly, subcritical experiments, 

engineering and production–and contributes to the science, research, and production that culminate in 

delivery of warheads to the Department of Defense (DoD).

The M&O workforce contains the bulk of the enterprise’s scientists, engineers, operators, technicians, 

and craft labor personnel, who are integral to achieving DOE/NNSA’s national security missions as it 

performs the design, testing, production, procurement, surveillance, and assessment of the warheads, 

their components, and the associated science and engineering required. The M&Os maintain the talented 

workforce and the facilities necessary for science-based stockpile stewardship. Additionally, they support 

nuclear non-proliferation, global material security, and other national security programs. 

The laboratories, plants, and sites reported 55,077 employees as of September 30, 2022. The national 

security laboratories5and the Nevada National Security Site reported 36,125 employees, while the 

production plants6reported 18,952 employees. Similar to Federal headcount, some employees perform 

work in support of other DOE/NNSA missions, such as Defense Nuclear Nonproliferation. Figure 7–2

displays the breakdown of workforce in terms of headcount across the national security enterprise. 

3 As defined in Section 5 of the Federal Activities Inventory Reform Act, Public Law 105-270, these are functions that are so 

intimately related to the public interest that they require performance by Federal Government employees. 

4 Attrition is 12.6 percent in FY 2022 if calculated using an average of workers over the course of the year from Federal Salaries 

and Expenses, which excludes the Office of Secure Transportation.

5

Los Alamos National Laboratory, Lawrence Livermore National Laboratory, and Sandia National Laboratories

6 Kansas City National Security Complex, Pantex Plant, Savannah River Site, and Y-12 National Security Complex
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Figure 7–1. The DOE/NNSA nuclear security enterprise

Figure 7–2. M&O and Federal share of total Weapons Activities workforce

7.1.3 Non-Management and Operating Workforce

The nuclear security enterprise also requires significant contributions from other people and corporations 

to fulfill its mission. The numerous line-item construction projects require hundreds of construction crews 

skilled in architecture, concrete fabrication; electrical engineering; plumbing; heating, ventilation, and air 

conditioning; masonry; and other trades. These trades are in high demand and may require innovative 

approaches to ensure their availability. For instance, Savannah River Nuclear Solutions entered into a 
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project labor agreement with the Augusta Building and Construction Trades Council, which is comprised 

of 19 local unions and supports the construction of the Savannah River Plutonium Processing Facility 

(SRPPF). The project agreement guarantees Savannah River Nuclear Solutions access to more than 2,500 

skilled trades and craft employees, whose work is crucial to completing this large and complex 

construction project.

Production and design agencies rely on complex supply chains to provide everything from 

supercomputers to raw materials. These suppliers must meet quality standards that exceed normal 

industry needs, and they must meet export control and other requirements. Many M&Os hire staff 

augments through subcontracts to provide key skills and assist permanent employees, while the Federal 

workforce similarly relies on support service contractors to fill numerous roles. Academic institutions that 

support DOE/NNSA through the academic alliances and partnerships are integral in providing a pipeline 

of highly skilled and educated talent into the enterprise. These individuals are not captured in the data 

and statistics displayed in this chapter, though their contributions are significant.

7.2 Status

DOE/NNSA must have a sufficient workforce with the right expertise and competencies to ensure it can

not only carry out its Stockpile mission but the full scope of DOE/NNSA’s missions as described in 

Chapters 1–6 of the FY 2024 Stockpile Stewardship and Management Plan and FY 2022 – FY 2026 Prevent, 

Counter, and Respond – NNSA’s Plan to Reduce Global Nuclear Threats. 

Along with the rest of the United States, the nuclear security enterprise experienced the “Great 

Resignation,” with turnover rates7for voluntary and involuntary attrition rising to nearly 11 percent from 

historic levels of approximately 6–7 percent. Retirement has historically been about half of the attrition 

rate across the laboratories, plants, and sites. As retirement eligibility continues to stand around 

21.6 percent and the percentage of employees classified as having 0–5 years of service rises to over 

50 percent, M&Os must grapple with the challenge of retaining personnel. For some programs, the 

process of getting a security clearance, getting cleared for the Human Reliability Program, and training to 

a basic level of competence takes 3 years. If DOE/NNSA does not retain a high percentage of these 

employees for extended periods of time, it will be difficult to guarantee a workforce with the necessary 

experience and technical judgment to perform the nuclear security mission. Each employee is valuable 

to the nuclear security enterprise, and as they build their skill sets though training and gaining experience, 

their value is enhanced. When an employee separates, it leaves a work gap that has to be filled by people 

busy with other jobs, and more training is required for someone else to fill that position. This results in 

an increased workload to the remaining staff.

As seen in Figure 7–3, although the attrition rate of 0–5 years of service is relatively consistent with the 

other groups in the top graph, the bottom graph shows that the sheer number of 0–5 years of service 

employees separating far exceeds the other groups since they comprise a disproportionately large 

segment of the workforce. The number of workers leaving the nuclear security enterprise is large and 

increased the past two years. The steep increase in separations of workers with 0–5 years of service 

corresponds with an even greater increase across the enterprise in new hires, so overall workforce 

numbers are still growing. Although DOE/NNSA is hiring more employees than ever before, it is struggling 

to retain those new hires.

7 Turnover rate was calculated by dividing the number of employees who separated during a given FY by the total number of 

employees at the beginning of that FY.
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Figure 7–3. Turnover rate trends
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DOE/NNSA is simultaneously losing its most experienced talent as retirements in the 26–30 years of 

service and 31+ years of service groups continue increasing. While the total number of separations from 

those two groups is constant, the percent of employees retiring is increasing because there are fewer 

employees left in those groups. The total years of experience across all M&Os is decreasing as the most 

experienced workers retire and fewer people with high levels of experience remain to replace them. 

Without cadres of workers staying long enough to learn from career workers that are retiring, new 

workers 20 years from now will have fewer mentors who fully understand the complex processes involved 

with design, manufacture, and testing of nuclear weapon components or of their assembly and 

disassembly. Commercial industry similarly is struggling to retain early career employees. M&Os have 

taken steps to help retain employees, such as implementing a mid-year compensation adjustment, using 

retention bonuses, authorizing larger merit increases, increasing promotion funds, and modernizing 

benefit offerings. The combination of these changes have proven effective as attrition rates have returned 

to historical norms. In addition, M&Os are working hard to determine the reasons employees are leaving 

so they can continue to offer desirable work environments. 

7.2.1 Workforce Demographics

As of September 30, 2022, the nuclear security enterprise consisted of 57,498 Federal and M&O 

employees.8 Since the last detailed workforce data reported in the FY 2022 Stockpile Stewardship and 

Management Plan (SSMP),9the nuclear security enterprise added over 8,260 employees during FY 2022 

and over 5,538 employees in FY 2021. During FY 2022, the enterprise experienced just under 5,592 

separations. Though there has been significant success in hiring, the required hiring targets increased in 

FY 2022 due higher-than-normal attrition. Hiring targets have started to decline as M&Os’ attrition has

stabilized.

It should be noted, all demographics discussions in the SSMP are based on headcount. Headcount 

includes every individual employee, each counted as “one” person, which is a useful measure for 

workforce discussions since it counts human beings. Counting full-time equivalent focuses on hours 

worked rather than individual employees, and is helpful when judging the level of effort required for a 

program. To illustrate, if there are two employees working part-time (for example, 20 hours per week)

on a given weapons activities program, they add up to one full-time equivalent, while the headcount value 

would be two. Since many employees work on multiple programs, the sum of full-time-equivalents will 

generally match headcount.

7.2.1.1 Common Occupational Classification System

DOE/NNSA uses the Common Occupational Classification System, which provides a set of mutually

exclusive occupation titles and definitions that cover the broad range of activities present in the 

DOE/NNSA complex, to consistently categorize workers across the nuclear security enterprise.10 As shown 

in Figure 7–4, the largest group comprises Engineers, followed by Professional Administrators, General 

Management, and Scientists. Technicians, Operators, and Crafts provide valuable hands-on work and 

together account for nearly 25 percent of the workforce.

8 This number does not include the Naval Reactors workforce nor support service contractors/augmented labor.

9 The FY 2023 SSMP contains a focused summary of separations and retention data, different from the detailed information 

required in even-year documents.

10 Common Occupational Classification System, Revision 3. Pacific Northwest National Laboratory, May 1996. This classification 

system was developed to assist DOE’s Environmental Management and DOE/NNSA’s Defense Programs jointly managed

workforce planning as production sites closed and Environmental Management work increased. 
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Figure 7–4. M&O Workforce breakdown by Common Occupational Code

7.2.1.2 Age

The enterprise workforce, when viewed in total, has a fairly even distribution across age groups from 26–60 

years old. A review of Figure 7–5 displays a slightly more even age distribution for the production sites, 

while the national security laboratories have a slightly higher number of younger employees. 

Figure 7–5. Workforce breakdown of national security laboratories, the Nevada National 

Security Site, and weapons production facilities by age group 

7.2.1.3 Years of Service

Due to increased hiring to support the growing scope of weapons modernization programs, nearly 

67 percent of the workforce has 10 or fewer years of service as shown in Figure 7–6. Over the last 2 years, 

the M&O workforce grew from a total of 46,762 employees at the end of FY 2020 to 55,077 at the end of 
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FY 2022. As reflected in the relatively even age distribution as compared to the more skewed years of 

service distribution, many new hires may be new to the enterprise but bring experience from a previous 

industry or position to specialized nuclear weapons work. It should be noted that workforce data is 

reported by each M&O, so if a person moves from a national security laboratory to a production plant, 

for example, they will appear in the data as a new hire. Whether an employee is recently graduated or 

new to the nuclear security enterprise, the lack of experience within weapons programs necessitates 

accelerating knowledge transfer activities and training for younger and/or less experienced personnel 

before specialized knowledge is lost due to retirements and separations. Once these new personnel are 

trained, retaining them is essential.

Comparatively, the Federal workforce shows a more even distribution in years of service, with many 

personnel having 11–15.11 

Figure 7–6. Workforce breakdown of national security laboratories, the Nevada

National Security Site, and weapons production facilities by years of service 

7.2.1.4 Separations

For separations, many of those with higher years of service are leaving due to retirement, as expected,

and shown in Figure 7–7. However, as previously noted, 71 percent of non-retirement, voluntary 

separations are in the 0–5 years of service category, as shown in Figure 7–8. Separations, both voluntary 

and retirements, have increased over the last two years, indicating the nuclear security enterprise faces 

increased competition for skilled labor and is struggling to retain the talent that it hires and trains. 

11 Federal workforce data, including a graphic representation of years of service, can be found in Appendix F.
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Figure 7–7. Total M&O separations by age group

Figure 7–8. Total M&O separations by years of service
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7.3 Managing the Workforce Career Cycle

The nuclear security enterprise population comprises highly skilled workforce with specialized training in 

technical, safety, security, and operational requirements. In many areas, these skills cannot be learned in 

the classroom and are not directly transferable from other industries. Areas in which specialized 

knowledge/experience is required include, but are not limited to, weapons design, high explosives 

manufacturing and surveillance, weapons system engineering, nuclear criticality safety engineering, 

radiation effects sciences, toolmakers, quality control and assurance, data science and high-performance 

computing, cybersecurity, welding, radar, and optics. This unique specialization of the enterprise 

workforce means that high retention rates, beyond what may be standard or desired in private industry, 

are essential for capability continuity. New staff require specialized training upon joining the nuclear 

security enterprise to augment their technical, vocational, or professional experiences prior to joining the 

nuclear security enterprise. These additional requirements include obtaining a security clearance, safety 

and security training, and, for many job categories, multi-year training and on-the-job internships. 

Retaining these uniquely qualified workers must be a priority.

Managing the entire career cycle—from early engagement, to recruiting and hiring, to developing and 

training, to retaining and, eventually retirement—requires dedicated human resources programs and 

mentorship, and strong consideration of new initiatives to meet the needs of the current workforce and 

to adapt to a changing environment. External factors, such as the availability of housing or childcare, also 

affect hiring and retention. Preferences for flexibility in location and schedule, more responsibility, and 

quick advancement challenge current models. The changing demographics, increasing separation 

between experienced workers and early-career staff, and increasing safety and security requirements 

place additional stress on workforce training and development.

During 2022, DOE/NNSA implemented many immediate initiatives and policy changes to help M&Os 

attract and retain talent. Some examples include:

◼ Implementing a first ever mid-year compensation adjustment to react in real time to the impact 

of the “Great Resignation”

◼ Increasing promotion budgets 

◼ Modifying the policy for benefits to allow laboratories, plants, and sites to modernize their benefit 

offerings as appropriate

◼ Introducing new provisions for compensation increases

Implementing these changes contributed to helping curb the increasing attrition rates across the 

enterprise. DOE/NNSA have continued to partner with the M&Os to determine reasonable ways to 

modernize policies for compensation and benefits throughout 2023 to ensure the M&Os have the tools 

needed to attract and retain talent. 

In recognition of the importance of looking ahead at the workforce that will be required in the future, 

DOE/NNSA commissioned the 2022 Strategic Outlook Initiative to focus on workforce. Sponsored by the 

NNSA Administrator with active engagement from all of the laboratories, plants, and sites, the Strategic 

Outlook Initiative sponsors enterprise-wide, strategic-level studies that look “over-the-horizon” to 

identify cross-cutting issues for DOE/NNSA over the next 5–20 years. The 2022 study concerning the 

nuclear security enterprise workplace of the future explores enterprise workforce needs 15–20 years from 

now and forecasts the character of that workforce within a range of work environments. The study

recommends a number of ways individual laboratories, plants, and sites can strengthen their workforces

and collaborate, as well as what DOE/NNSA can do to support the workforce of the future.
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7.3.1 Early Engagement

The nuclear security enterprise operates early 

engagement programs and initiatives to attract talent 

from a broad set of disciplines and specialties. Federally

sponsored Academic Programs as well as site-specific 

programs engage promising candidates with technical 

and/or trade skills. Examples of engagement activities 

include participation in internal and external career fairs, 

high school outreach activities, trade and vocational 

programs, student (undergraduate, graduate, and 

postdoctoral) appointment offerings, and partnerships 

with local colleges and universities. Each M&O has established technical and strategic programs to attract 

the skills critical to their specific missions.12 DOE/NNSA continues to recruit jointly at university hiring 

fairs and virtual fairs, which are designed to show candidates the breadth of options for geographic 

location or career specialization that the nuclear security enterprise offers. Early engagement is critical 

to maintain a robust pipeline of individuals with the skills and motivation to contribute to national nuclear 

security missions. 

Both DOE/NNSA and M&O senior leadership have expressed serious concerns about the future of the 

STEM workforce. DOE/NNSA must prioritize investments in undergraduate, graduate, and postdoctoral 

researchers, particularly those performing research of interest to DOE/NNSA, taking into consideration

that the requirement to attain and hold a security clearance makes the pool of potential candidates 

smaller. DOE/NNSA continues its six strong Academic Programs that support a host of different science 

and engineering fields, including materials science, high energy density physics, nuclear science, 

computational science, modeling, and simulation. These programs, in particular the Minority Serving 

Institution Partnership Program (MSIPP) and the Tribal Education Partnership Program (TEPP), lead 

nationally in promoting diversity, equity, inclusion, and access in STEM research.

DOE/NNSA identified a need to expand its programs and is working to attract STEM talent from numerous 

institutions. DOE/NNSA has launched the Apprenticeships for Complete and Committed Employment for 

Specialized Skills (ACCESS) Program to bolster existing and create new apprenticeship programs to 

develop the technicians and skilled craft trade workers needed to meet the ongoing and emerging needs 

of the complex. In FY 2023, Academic Programs supported 18 Centers of Excellence, 62 grants, 33

consortia, and 150 fellows engaged in research relevant to the nuclear security mission. In FY 2024, the 

addition of Pipeline Development will increase DOE/NNSA’s presence within the scientific community and 

expand the pool of STEM talent throughout the nation who are identified, recruited, cleared, and retained 

in the nuclear security enterprise.

7.3.1.1 Academic Programs

Academic Programs is designed to support investments in science and engineering disciplines of critical 

importance to DOE/NNSA’s nuclear security enterprise, including nuclear science, radiochemistry, 

materials at extreme conditions, high energy density science, advanced manufacturing, and 

high-performance computing. The program’s grants, centers, fellowships, and other funding options offer 

an introduction to the mission and people in the national laboratories, establishing a workforce pipeline 

to strengthen the future enterprise. The programs focus on quality science through competitive award, 

12 Site-specific early engagement initiatives and academic alliance programs are in Appendix F.

Enterprise-Wide Student and Early Engagement

(October 1, 2021–September 30, 2022)

• Total Interns: 431

• Total Postdoctoral Fellows: 1,550

• Total Students: 4,722

• NGFP Fellows: 60

• MSIPP/TEPP Interns: 245
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connection with DOE/NNSA mission work at the national security laboratories and nuclear weapons 

production facilities, and a view to the nuclear security enterprise’s future needs and opportunities.

Academic Programs has three goals: 

1. Develop the next generation of diverse, highly trained technical workers able to support 

DOE/NNSA’s core missions

2. Maintain technical expertise external to the nuclear security enterprise for providing valuable 

oversight, cross-check, and peer review

3. Enable innovation to enhance nuclear security enterprise missions and to strengthen key fields of 

research relevant to DOE/NNSA

The Academic Programs comprises six subprograms:

1. Stewardship Science Academic Alliance: This program supports scientific academic research 

programs to develop the next generation of highly trained technical workers able to support the 

core DOE/NNSA mission and to ensure there is a strong community of technical peers (external to 

the NNSA national laboratories) capable of providing peer review and scientific competition to 

strengthen the basic fields of research relevant to the nuclear security enterprise. Stewardship 

Science Academic Alliance funding supports research at approximately 80 universities, including 

training of over 200 graduate students and postdoctoral researchers. This program includes the 

Stewardship Science Graduate Fellowship and Laboratory Residency Graduate Fellowship 

programs.

2. MSIPP: This program provides competitive, consortia-based grant awards with a 3- to 5-year period 

of performance to minority-serving institutions who partner with the nuclear security enterprise to 

prepare DOE/NNSA’s next-generation workforce in the STEM disciplines.

3. TEPP: Similar to MSIPP, this program provides 3- to 5-year grants to tribal serving institutions who 

partner with the nuclear security enterprise. MSIPP and TEPP continue to expand the nuclear 

security enterprise’s STEM pipeline while improving the diversity of the workforce by recruiting 

from underrepresented populations.

4. Joint Program in High Energy Density Laboratory Plasmas: This program is designed to steward the 

study of laboratory high energy density plasma physics by funding academic research of ionized 

matter in laboratory experiments where the stored energy reaches approximately 100 billion joules 

per cubic meter (i.e., pressures of approximately 1 million atmospheres). 

5. Computational Science Graduate Fellowship: This program cultivates the next generation of 

scientists and engineers in computational sciences, physical sciences, engineering, mathematics, 

and data science fields including artificial intelligence and machine learning. For DOE/NNSA, it

supports the Advanced Simulation Computing and Stockpile Modernization missions by establishing 

academic programs for multidisciplinary simulation science and providing students an opportunity 

to collaborate with world-class researchers and scientists on high performance computing subjects 

for solving complex science and engineering problems develop weapons codes through open 

science applications.

6. Predictive Science Academic Alliance Program: This program engages with leading U.S. universities, 

focusing on the development and demonstration of technologies and methodologies to solve open 

science and engineering application problems. Predictive science is based on verification, 

validation, and uncertainty quantification methodologies for large-scale simulations. 
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A recent addition to the Academic Programs is the National Lab Jobs ACCESS Program that provides

apprenticeships in the skilled and cyber trades needed to fill a widening gap in the workforce at the 

nuclear security enterprise laboratories, plants, and sites. The ACCESS Program also funds

pre-apprenticeship and apprenticeship programs to train a skilled workforce in the trades needed at by

DOE/NNSA, such as machinists, welders, information technology and cybersecurity professionals, fissile 

material handlers, and industrial hygienists. The ACCESS Program requires a partnership between preapprentice or apprentice program sponsors and a national laboratory, site, or plant to define the skillsets 

needed by technicians at those facilities and then provides funding to tailored training programs. 

7.3.1.2 NNSA Graduate Fellowship Program

The NNSA Graduate Fellowship Program has been administered by Pacific Northwest National Laboratory 

for over 25 years with a goal of identifying and developing the next generation of diverse and talented 

leaders to strengthen the nation through nuclear security work. The program routinely brings in top talent 

and provides several opportunities for fellows to work alongside experts, support major events, and engage 

in professional development opportunities. The fellows are assigned to work with a program office, field 

office, M&O, or other agency involving nuclear issues for a one-year term. The program has steadily grown 

over the years, from an initial cohort of 3 fellows in 1995 to recent cohorts of 60 fellows, and has over 

500 alumni. Over the life of the program, about 90 percent of the NNSA Graduate Fellowship Program 

fellows continue to serve the Nation in a national security capacity (see Figure 7–9).

Figure 7–9. NNSA Graduate Fellowship Program Class of 2021–2022

Post-Fellowship Employment13

7.3.2 Recruitment and Hiring

DOE/NNSA and its M&Os continue to increase hiring to meet mission requirements, adding over 

8,260 employees during FY 2022 and over 5,538 employees in FY 2021.

14

13 In this graph, NNSA represents Federal hires; nuclear security enterprise represents fellows hired by DOE, national laboratories, 

and DOE/ NNSA contractors; National Security Sector represents fellows who accepted employment with other national security 

stakeholders such as Department of State or Defense Threat Reduction Agency; and Other represents fellows who returned to 

academia or whose employment was unavailable at the time of publication.

14 Data for the FY 2024 SSMP was collected as of September 30, 2022.
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DOE/NNSA and M&Os have changed their recruiting strategies based on the demands of the job market 

to conduct more proactive sourcing, allowing them to reach the passive and active candidates as well as 

better compete with industry. DOE/NNSA has focused on recruiting a diverse Federal workforce, and 

leverages its excepted service hiring authority to hire uniquely qualified candidates for specialized roles. 

Each M&O employs strategies that address its unique recruiting and hiring challenges. For instance, the 

Kansas City National Security Campus (KCNSC) launched an initiative to recruit and hire graduating high 

school students who have no prior work experience. As a result, future generations can now start a career, 

gain experience, and develop useful skills in an advanced manufacturing facility, while earning a 

competitive salary. For more recruitment and hiring strategies, see Table 7–1.

7.3.3 Developing and Training

Since the DOE/NNSA workforce requires unique skills, many of which must be acquired through on-thejob training or through learning from experienced mentors, it is imperative to build programs that support 

this capability development, training, and knowledge transfer.

Implementing training and knowledge-transfer programs to mitigate the loss of expertise through the 

retirement of experienced personnel continues to be an area of emphasis for the enterprise. Increased

stockpile modernization workloads provide increased opportunity for new employees to learn on the job. 

This approach must be done in tandem with adequate mentoring and guidance to be an effective method 

of knowledge transfer. Many M&Os, especially the national security laboratories, have mentoring 

programs in place as part of employees’ career development. Once new employees are trained in a 

program, they must be retained for these programs to achieve long-term benefit. Additionally, each 

laboratory, plant, or site must look ahead to determine future need so that trained personnel will be 

available and will have had time to learn from experienced personnel.

7.3.3.1 Laboratory, Plant-, and Site-Directed Research and Development

Laboratory-directed R&D programs play a significant role in the development of the workforce. These 

programs fund high-risk and potentially high-payoff research projects aimed at developing science and 

technology tools and capabilities to meet future national security challenges and create vibrant R&D 

communities that are attractive to high caliber personnel, including both new and experienced 

researchers. Consequently, DOE/NNSA benefits not only from the expertise of the individuals, but also 

the establishment of long-term relationships with future recruits and the academic institutions at which 

they study. These programs have developed postdoctoral paths that help transition in-demand 

researchers to full-time career employees and provide opportunities to introduce new hires to the nuclear 

security enterprise. The ability to conduct R&D in DOE/NNSA’s state-of-the-art facilities is attractive, and 

these programs pave the way for early career scientists and engineers to find a lifelong professional home 

where their knowledge will be utilized in mission-relevant research. For instance, Lawrence Livermore 

National Laboratory (LLNL) recently opened the Advanced Manufacturing Lab, where employees 

collaborate with industry to “spin in” and “spin out” advanced manufacturing technologies.

Plant- and Site-directed R&D, which contribute to developing future capabilities, have historically been 

directed by Federal Program Managers to address specific needs. Plant- and Site-directed R&D leverages 

the knowledge and talent of skilled professionals to find solutions to relevant challenges. Plant-directed 

R&D proposals engage in research, development, and demonstration activities with respect to 

engineering and manufacturing capabilities related to DOE/NNSA missions. Many of these activities not 

only support DOE/NNSA missions, but also include academic partnerships as a workforce pipeline, 

bringing university talent into the plants. This partnership permits students working on research at their 

universities to continue that research after graduation with full time employment at a plant. 
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7.3.3.2 Training Initiatives

DOE/NNSA sponsors several training programs for Federal employees, from “NNSA 1st Year” that 

introduces new employees to the agency to Supervisory Training that provides senior employees with the 

tools and skills to promote a positive workplace. DOE/NNSA’s Learning and Career Management sponsors 

opportunities in numerous Leadership Development Programs as well as rotations or details to other 

offices within DOE/NNSA. These programs promote learning, development, and training to all Federal 

employees for their and the organization’s benefit.

M&Os are taking innovative approaches to training to meet the demands of onboarding numerous new 

hires. For instance, KCNSC deployed four extended reality applications to safely and effectively enhance 

employee onboarding, with more applications in development. The four applications are Visually 

Enhanced Guidance Application, a virtual reality roller mill training, a virtual reality electrical tester 

training and a virtual reality forklift training. All applications are currently deployed to new employees in 

specific job classifications (inspectors, production fabricators, assemblers, transportation personnel) so 

they can safely train in a virtual environment, allowing learners to build muscle memory for expected 

behaviors. Significant results from these applications include:

◼ Zero safety incidents have occurred on the Roll Mill since implementing the training

◼ Virtual Reality training contributed to a 66 percent reduction in training cycle time for electrical 

inspectors 

◼ Number of average instructor interventions during electrical tester training decreased from 16.37 

to 2

◼ Visually Enhanced Guidance Application increased inspector efficiency by eliminating or reducing 

questions to engineers

As part of its plutonium pit production recovery strategy, DOE/NNSA is continuing to work with LLNL and 

Los Alamos National Laboratory (LANL) to capture efficiencies based on knowledge gained from pit 

production efforts. Lessons learned from production experience at LANL will be used to minimize the 

time needed to produce the first War Reserve pit and achieve full capacity at SRPPF after the completion 

of construction. A key part of the knowledge-transfer plan is construction of a High-Fidelity Training and 

Operations Center at Savannah River Site (SRS), which will be completed and begin its pit development 

and training mission several years before Savannah River Plutonium Processing Facility’s main processing 

building is completed. 

7.3.3.3 Knowledge Preservation 

In recognition of the need to transfer knowledge from senior to junior staff, DOE/NNSA established the 

Knowledge Preservation Initiative as part of the NNSA 2021 Safety Roadmap. One of the key elements is 

to capture and retain the crucial knowledge and experiences of DOE/NNSA subject matter experts, senior 

leaders, and managers, all of whom have a wealth of experience in a multitude of challenges DOE/NNSA 

has faced over the decades. As DOE/NNSA is currently experiencing a large talent turnover, this 

experience must be captured and retained for the benefit of incoming staff. The National Training Center 

partnered with the NNSA Safety Roadmap initiative to capture and retain these knowledge elements, 

creating media that will be used to enhance current training efforts and to provide content for new and 

innovative approaches to retain and transfer knowledge. Additionally, DOE/NNSA contracted 

TechSource, Inc. to develop curriculum for the Weapons Knowledge Preservation and Transfer Program, 

a series of courses presented by subject matter experts. These efforts will contribute to DOE/NNSA 

maintaining a Federal staff in the top tier technically.
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Sandia National Laboratories (SNL) sponsors the Weapon Intern Program (WIP) to benefit the entire 

nuclear security enterprise. WIP was created in 1998 to accelerate the learning process and transfer 

decades of knowledge and experience in all phases of the nuclear weapon life cycle, from experienced 

weaponeers to the new generation of stockpile stewards. With over 450 program graduates, the WIP

turns out about two dozen students each year from all sites in the nuclear security enterprise, DOE/NNSA, 

and DoD officers/civilians. Topics include various weapon technology, design, development, evaluation, 

production, operations, process, policy, and management areas. SNL leverages this program to transfer 

decades of nuclear weapon-related knowledge and experience to new generations of nuclear 

weaponeers. The primary objective of the WIP is to significantly accelerate the process of providing this 

understanding to individuals who are new to the nuclear weapons area. This transfer of knowledge and 

experience is delivered through a blended learning environment consisting of live and multimedia-based 

classroom instruction and briefings, individual and team research projects, hands-on activities, and site 

visits to various DOE/NNSA and DoD facilities and operations. The live instruction is provided by a large 

contingent of subject matter experts in the various weapons technology, design, development, 

evaluation, production, operations, policy, and management areas. The WIP also includes a strong senior 

mentor element that helps the interns directly link the past to the present and the future. The curriculum 

continuously evolves to better address the challenges of maintaining the nation’s nuclear deterrent for 

the future.

Sites also maintain knowledge preservation programs unique to the technical knowledge required to 

accomplish their missions. For instance, the Y-12 National Security Complex (Y-12) Knowledge 

Preservation Management System allows for the capture, management, and web-based access of 

manufacturing operations information. In one use case, the Knowledge Preservation Management 

System interviewed technicians who had retired from Y-12 in preparation for re-starting the wet chemistry 

process to support producing lithium-based materials. Reference Appendix F for additional site-specific

details. 

7.3.3.4 Pipeline Changes

Changes in workforce dynamics, and specifically the high percentage of workers who have 0–5 years of 

experience, necessitate changes in training pipelines. Whereas previous models may have relied on oneon-one mentoring over the course of years, modern programs must reach a larger number of new 

employees and must help new employees up the learning curve more quickly. After considering the time 

required to obtain a security clearance, get certified through the Human Reliability Program to interact 

with nuclear materials, and conduct on-the-job-training, an operator may not be fully ready to work until 

two or more years after being hired. For instance, SRS operator qualifications take approximately two 

years to complete, so the site has adjusted its pipeline by hiring in advance of need and by training 

personnel in an uncleared area so they can begin learning basic skills before receiving a security clearance. 

Leveraging technology, SRS plans to build an unclassified simulator in a new office building to expedite 

operator training while clearances are being processed.

Recognizing an increasing need for Radiological Control Technicians, LANL partnered with Northern New 

Mexico College to establish a training pipeline for Radiological Control Technicians. This competitive 

academic opportunity provides tuition and fees for a full-time student, a paid student internship at LANL, 

and transition to full time employment upon graduation with an associate degree, providing the student 

meets all LANL eligibility requirements. DOE/NNSA must continue modernizing its training pipelines to 

adapt to workforce realities and meet mission needs while ensuring safety and security.
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7.3.4 Retaining and Sustaining

DOE/NNSA’s greatest workforce challenge is retaining the talented personnel it hires. As workforce 

demographics have shifted over time, the proportion of workers with 0–5 years of experience has 

continued growing and constitutes as much as 70 percent of the population at some M&Os. While the 

proportion of new workers leaving is somewhat higher than those with 5–10 years of experience and is 

actually less than those with more than 20 years of experience, their departures are acutely felt since their 

numbers are largest. As shown earlier in Figure 7–3, the nuclear security enterprise is experiencing a 

sharp rise in turnover rate, necessitating a renewed focus on retention. 

Numbers alone cannot tell the full story of retention challenges since they do not reflect the vital skills or 

level of experience that people take with them when they leave. Additionally, retaining early career 

workers is important for long-term knowledge preservation; without cadres of workers growing 

experienced, the new workers 20 years from now will have fewer mentors who fully understand the 

complex processes involved with design, manufacture, and testing of nuclear weapon components or of 

their assembly/disassembly. In anticipation of future needs, the Strategic Outlook Initiative for 2022 is 

developing recommendations to ensure the workforce of the future will be ready to carry out the mission.

In response to this increased turnover rate, M&Os are tailoring approaches to address the needs of their 

unique workforces. SNL held an internal hiring fair to advertise openings to current employees, allowing 

them to continue growing in their careers or to seek new challenges while staying at SNL. Recognizing the 

burden of commuting to a remote location, Nevada National Security Site offers additional paid time off 

for employees who are required to work on site in an effort to retain the employees. KCNSC is leveraging 

DOE/NNSA’s unique mission as a retention strategy for employees. As examples, KCNSC is hosting Mission 

Engagement Series classes and bringing in guest speakers to discuss current events (these can potentially 

reach nearly 1,800 employees), hosting a Nuclear Policy Book Club, and running a U.S. Strategic 

Command-like tabletop exercise.

DOE/NNSA also recognizes the value of flexible schedules and work-life balance, and is striving to 

modernize its approach. The last several years have seen the rise of remote work and hybrid work, initially 

in response to Coronavirus-related risks, for those workers whose positions permit it. DOE Headquarters 

has transitioned to a hybrid workplace, which can expand the hiring pool, attract high-talent job 

candidates, retain talent and maintain a work-life balance, and has curated a collection of resources to 

help navigate working, collaborating, and leading in a hybrid workplace. M&Os are adapting as well; for 

instance, SNL officially implemented a hybrid work model and currently has nearly 4,000 employees under 

a telecommuting agreement or a remote work agreement. M&Os whose missions require onsite work 

have instead offered different schedules, such as a 4-day workweek composed of 10-hour workdays, or 9 

days of work totaling 80 hours over the course of two workweeks. To permit even more workers to take 

advantage of remote opportunities, DOE/NNSA is investigating the possibility of computing hubs and 

other resources, and must continue to modernize its approach to workforce management.

7.4 Challenges and Strategies

While recruiting, developing, and retaining the specialized workforce needed to accomplish the mission 

is a challenge, DOE/NNSA and its M&Os are employing tailored strategies to meet the demands of the 

weapons program. The nuclear security enterprise sites operate under individual M&O contracts and 

budgets, with unique compensation and benefit offerings determined by their site. Yet all the 

laboratories, plants, and sites are held to the same requirements, with flexibility in implementation based 

on their distinct requirements. DOE/NNSA requires similar deliverables from its laboratories, plants, and 

sites with the same due date, which allows DOE/NNSA to consider and review all requests with an 
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enterprise-wide view to ensure decisions are made for the collective good. There have been multiple 

collaborations across the sites to discuss retention concerns and to share ideas and best practices in 

benefits, compensation, and remote work. Additionally, DOE/NNSA has created sub-teams made up of 

representatives from the sites to further evaluate compensation, benefits, and general retention; their 

suggestions resulted in changes to the contracts and/or processes.

Table 7–1 provides a summary challenges and strategies for recruiting, developing, retaining, and 

sustaining the workforce. Several current and future strategies come from the Enhanced Mission Delivery 

Initiative, a study team commissioned by the Office of the Administrator to identify obstacles to agility 

and responsiveness across the nuclear security enterprise and to assess the state of relationships between 

the Federal and the M&O workforce. The Enhanced Mission Delivery Initiative’s goal is to develop 

actionable solutions and determine which Departmental authorities should implement them, enhancing

DOE/NNSA’s ability to meet near- and mid-term deliverables. Since several of their recommendations 

pertain to workforce, they are included in Table 7–1 and marked with an asterisk.

Table 7–1. Summary of challenges and strategies for recruiting, developing, retaining, and sustaining 

the workforce

Topic Area Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Recruitment 

and Hiring

Competition for highdemand disciplines and 

limited availability of 

qualified candidates with 

advanced engineering 

degrees

• Expand recruiting capability by partnering 

with local academic institutions

• Increased emphasis on internships and 

apprenticeships

• Modernize talent acquisition model

• Engage employees with the mission and 

work-life balance

• Continue building relationships 

with academic institutions

• Develop pipelines that reach 

potential candidates early in 

their careers

• Develop postgraduate programs 

with opportunities to become 

career employees

• Relocation benefits to allow 

national recruitment of highdemand/hard to find disciplines 

Increasing demand for 

employees due to 

growing missions

• Allow recruiting teams to increase efforts 

in ability to offer on the spot job offers

• Nuclear security enterprise-wide hiring 

fairs to help candidates find their right fit

• Expand use of on-the-spot job 

offers

• Further expand joint hiring 

events for the nuclear security 

enterprise

Attractive, market 

competitive salary and 

benefit packages

Employee and candidate 

expectations for remote 

work, inclusivity and 

engagement have 

increased

• NNSA – Demonstration Project, 

performance pay

• NNSA authorized a mid-year 

compensation adjustment for all 

laboratories, plants, and sites to help 

stem attrition 

• NNSA evaluate ways to reduce 

and/or remove certain controls 

on M&O employee 

compensationa

• NNSA evaluate ways direct 

compensation and variable 

compensation can be applied to 

attract and retain employeesa

Hiring people with the 

right skills in anticipation 

of future mission needs

• Laboratories, plants, and sites complete 

workforce plans to determine needs of 

the site 

• Continue honing projections and 

skill sources

Remote geographic 

location of some sites, 

results in difficulty 

recruiting nationally

• Target qualified candidates via university 

partnerships

• Increase emphasis on local hiring and 

training, as well as internships and 

apprenticeships to increase the local pool 

of technologists and craft workers

• Partner with civic organizations to 

leverage a marketing about locations

• Ensure appropriate and 

competitive pay is provided to 

employees in dispersed 

geographic regions
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7.5 Workforce Accomplishments

The technical accomplishments of the nuclear security enterprise workforce enable DOE/NNSA to meet 

its mission while providing significant contributions to research 

and development of new science and technologies. These 

accomplishments are cutting-edge, far-ranging in scope and 

effect, and indicative of the uniquely talented, highly educated, 

and highly trained workforce. The quality of the work being 

accomplished is also evident from the numbers of publications, 

awards, patents, and other external recognitions that have been 

bestowed on members of this workforce.

Collectively, the sites have had more than 5,000 technical, 

peer-reviewed journal articles published over the last two years. At least 20 employees have been granted 

Topic Area Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Development 

and Training

Increasing turnover of 

key talent in missioncritical weapons work 

strains ability to develop 

the next generation of 

experienced engineers

Knowledgeable members 

of the workforce with 

unique experiences are 

retiring

• Knowledge preservation initiatives, which 

are operating at varying levels of success

at each location within the nuclear 

security enterprise

• Implementation of retention programs 

across the nuclear security enterprise to 

improve retention for critical work in the 

weapons modernization programs

• NNSA work with the M&Os to 

develop a common plan to allow 

M&O annuitants and retirees to 

be compensated fairly for postretirement service that 

contributes to the delivery of the 

primary NNSA missions

• Development of a 

comprehensive knowledge 

management strategy

Desire for mentorship • NNSA – Learning and Career 

Management offers mentoring, coaching, 

and other development programs

• Developing programs for employees for 

mentorship and career growth 

Enhance mentoring programs and 

career ladder opportunities

Infrastructure needed to 

train a growing workforce 

are already near or at 

capacity, causing delays

• Smaller class size, off-site locations, and 

room to room virtual presentation

• Leverage online training capabilities to 

support increased demand

• Dedicated training space for new 

and uncleared personnel

• Integrate needs for both training 

and execution spaces in future 

infrastructure investments

Retaining and 

Sustaining

Retain the talent 

DOE/NNSA has trained

within the enterprise

• Enhancements to compensation and 

retention programs

• Integrated workforce planning

• Enhanced pre-onboarding/on-boarding 

program

Evaluate NNSA policy for M&O 

service credit recognition policy 

across the enterprise

Continued attrition due 

to increased commercial 

opportunities outside of 

nuclear security 

enterprise

Attrition is most acute for 

those with less than 5 

years of service

• Modernize employee benefit offerings

• Continue conducting exit surveys, 

engagement surveys, and stay surveys

• Evaluate compensation surveys used to 

ensure survey data is accurate of industry 

competitors

• Improve organizational culture

• Enhance employee recognition 

programs and employee 

engagement programs

M&O = management and operating

a

Indicates a recommendation from the Enhanced Mission Delivery Initiative

Workforce Accomplishments

(2021–2022)

• Journal Articles Published: approx. 5,000 

• Patents Granted: approx. 150

• Technical Fellows: 16

• R&D 100 Awards: 30

• Diversity Awards: over 40
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fellowship in several prestigious technical societies, such as the American Association for the 

Advancement of Science, the American Physical Society, and the Institute of Electrical and Electronic 

Engineers. Over a dozen employees or teams received accolades on their efforts to promote diversity, 

equity, and inclusion. Members of the nuclear security enterprise led projects that won R&D 100 awards, 

awards from the American Physical Society and American Nuclear Society, DOE’s Ernest O. Lawrence 

Award, and numerous other recognitions from national and local technical organizations. 

The innovation and intellectual capital of the enterprise is also apparent in the number of patents and 

invention disclosures attributable to the nuclear security enterprise. Together, the sites were granted 

more than 150 patents in the last two years and filed applications for many times that number. These 

patents and innovations benefit not only the nuclear weapons enterprise but the broader R&D 

community. 
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Chapter 8

Budget and Fiscal Estimates

The Fiscal Year (FY) 2024 President’s Budget for Weapons Activities supports the nuclear stockpile and 

associated programs that provide required capabilities. The FY 2024 President’s Budget provides an 

increase of 7.6 percent1for the Department of Energy’s National Nuclear Security Administration

(DOE/NNSA) and an increase of 10 percent for Weapons Activities above the FY 2023 enacted

appropriation. DOE/NNSA developed the FY 2024 Future Years Nuclear Security Program (FYNSP) budget 

request for Weapons Activities by evaluating the resources necessary to support the plans described in 

the previous chapters, which synchronize DOE/NNSA’s warhead deliveries with the modernization of 

Department of Defense (DoD) delivery platforms.

The first part of this chapter displays budgetary information for the FY 2024 budget request based on the 

program of record described in the previous chapters of this Fiscal Year 2024 Stockpile Stewardship and 

Management Plan (FY 2024 SSMP). Sections 8.4–8.8 compare the FY 2024 budget request to the FY 2023

enacted budget by program/budget line and present key milestones, showing progress toward program 

goals. Key milestones beyond the next 5 years show planned activities to meet DoD requirements and 

are contingent on future decisions and funding levels.

Section 8.9 describes cost projections for selected programs beyond FY 2024 and the basis of those cost 

projections. The cost-estimating techniques supporting the budget request are consistent with 

Government Accountability Office best practices, and the estimates have been updated with current 

requirements for each weapon system. The chapter concludes with an overview of the 25-year plan and 

an analysis of the affordability of the Weapons Activities program.

8.1 Planning, Programming, Budgeting, and Evaluation

DOE/NNSA employs a Planning, Programming, Budgeting, and Evaluation (PPBE) process similar to 

processes in use across the U.S. Government. DOE/NNSA’s PPBE process has four major phases for each 

budget cycle: 

◼ The Planning phase of the PPBE process evaluates the range of work required in a manner that is 

fiscally informed, but not constrained, to ensure all requirements and mission needs are 

considered. This phase is guided by strategic goals and objectives specified in Department-level 

and NNSA-level strategic planning documents. These internal strategic documents are aligned

with and support the mission priorities in the National Security Strategy, National Defense 

Strategy, and Nuclear Posture Review. Internal documents are also developed in consultation 

with the program offices and management and operating (M&O) contractor partners to ensure 

they reflect a complete set of requirements. This phase drives the development of a range of 

strategies, alternatives, and plans that accomplish timely execution of key mission priorities and 

enables DOE/NNSA to achieve its mission.

1 The FY 2023 enacted level for NNSA does not reflect the mandated transfer of $99.75 million from Naval Reactors to the Office

of Nuclear Energy for operation of the Advanced Test Reactor.
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◼ The Programming phase is the decision-making process that aligns available program resources 

with priorities, resulting in a balanced, integrated, executable FYNSP to be proposed by DOE to 

the Office of Management and Budget (OMB) as the basis for that year’s congressional budget 

request. This phase is primarily a Headquarters-driven process that allocates resources and 

integrates the funded activities to ensure accomplishment of the highest priority efforts. 

◼ The Budgeting phase involves the production of a formal budget request and associated 

justifications to OMB and to Congress as well as execution of appropriated funds. DOE/NNSA 

develops budget justification materials for the FYNSP that describe work scopes and schedules 

corresponding with the funding request. Budgeting includes formulation, justification, execution, 

and control of the budget. This process describes to Congress the resources necessary to execute 

the mission and then ensures DOE/NNSA spends those resources in accordance with the law. 

Budget Formulation is the development of fund estimates that support the plans and programs 

and obtains resources for program execution. Budget Justification includes the development of 

the budget and supporting documentation that allows the stakeholder to understand the 

program, or function, and the resources required to accomplish the effort. Budget Execution is 

the phase in which appropriated resources are distributed and controlled to achieve their 

approved purpose. After Congress passes and the President signs appropriations bills, the 

apportionment process makes funds available to DOE for obligation and expenditure. 

Appropriation legislation and accompanying tables are the controlling documents for funds 

distribution and display the budgetary resources available. Execution is the consistent monitoring 

of expenditures and obligations.

◼ Evaluation is the assessment of progress made toward achieving identified performance 

measures at multiple levels within DOE/NNSA, including evaluation of the performance of the 

M&O contractors.

At any time, multiple PPBE phases for different budget cycles are ongoing concurrently.

8.2 Portfolio Management

DOE/NNSA continues to implement portfolio management, leveraging best practices from industry and 

recommendations from the Government Accountability Office. 

Portfolio managers monitor, evaluate, and validate the portfolio components—such as programs and 

projects—that comprise their portfolios with respect to alignment with organizational strategy and 

objectives; they also manage resource distribution across these portfolio components. The President’s 

Budget for Weapons Activities funds a set of programs based on analysis of what actions are necessary to 

accomplish DOE/NNSA’s statutory mission to manage the current and future stockpile without nuclear 

explosive testing. During the programming process, funding levels are established at various levels of 

detail for the FYNSP period to align anticipated resources with DOE/NNSA priorities.
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8.3 Fiscal Year 2024 Future Years Nuclear Security Program

The FY 2024 FYNSP budget request supports the current stockpile, warhead modernization activities, 

recapitalization and modernization programs for infrastructure, and reestablishment of necessary 

production capabilities. It also supports research and development (R&D) efforts and implementation of 

enhanced experimental and computational capabilities. 

Table 8–1 displays the FY 2023 enacted budget, and the program budget requests for Weapons Activities 

for FY 2024 to FY 2028. The structure of the budget request in Table 8–1 reflects the major programs, 

which are described in Chapters 2–7. The figures and narrative that follow describe the FY 2024 budget 

request in more detail. 

Table 8–1. Overview of Future Years Nuclear Security Program budget request for

Weapons Activities in fiscal years 2023–2028

a

Activity

FY (dollars in millions)

2023

Enacted

2024

Request

2025

Request

2026

Request

2027

Request

2028

Request

Stockpile Management 4,954.1 5,204.9 5,088.4 4,987.1 5,205.6 5,273.9 

Production Modernization 5,116.7 5,555.9 5,560.5 5,732.8 5,847.2 6,134.2 

Stockpile Research, Technology, and Engineering 2,950.0 3,196.6 3,493.9 3,477.6 3,454.7 3,436.5 

Academic Programs and Community Support 111.9 152.3 172.8 193.9 194.9 202.4 

Infrastructure and Operations 2,602.6 2,767.1 2,943.3 3,198.2 3,214.2 3,309.6 

Secure Transportation Asset 344.4 357.1 391.0 413.2 460.6 464.7

Defense Nuclear Security 872.1 1,016.8 1,020.5 1,025.4 1,104.5 1,127.9 

Information Technology and Cybersecurity 445.7 578.4 664.4 726.6 763.1 758.7 

Legacy Contractor Pensions and Settlement 

Payments 114.6 65.5 56.3 64.2 40.9 39.4 

Adjustments (396.0) (61.6) 0.0 0.0 0.0 0.0 

Weapons Activities Total 17,116.1 18,832.9 19,390.9 19,818.9 20,285.7 20,747.4 

a Totals may not add because of rounding. 

8.4 Stockpile Management

Stockpile Management encompasses five major subprograms that directly support the Nation’s nuclear 

weapons stockpile: (1) Stockpile Major Modernization, (2) Stockpile Sustainment, (3) Weapons 

Dismantlement and Disposition, (4) Production Operations, and (5) Nuclear Enterprise Assurance (NEA). 

Additional information about the Stockpile Management program can be found in Chapter 2, “Stockpile 

Management.”

8.4.1 Budget

The budget request for Stockpile Management increased 5.1 percent from the FY 2023 enacted budget

and is illustrated in Figure 8–1. 
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Figure 8–1. Fiscal year 2024 President’s Budget Request for Stockpile Management

8.4.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023

Enacted Budget

8.4.2.1 Stockpile Major Modernization

Stockpile Major Modernization extends the lifetime of the nation’s nuclear stockpile while addressing 

required updates; replacing aging, or obsolete, components to ensure continued service life; and 

enhancing security and safety features. Stockpile Major Modernization includes (1) B61 Life Extension 

Program (LEP), (2) W88 Alteration (Alt) 370 Program, (3) W80-4 LEP, (4) W87-1 Modification (Mod)

Program, and (5) W93 Program. 

The budget request for Stockpile Major Modernization increased to support:

◼ W87-1 execution of Phase 6.3, Development Engineering

◼ W93 ramp-up within Phase 2, Feasibility Study and Design Option

◼ W88 Alt 370 risk mitigation

These increases are partially offset by decreases in the B61-12 LEP due to ramp-down in production 

activities and in the W80-4 LEP due to completion of some development activities.

8.4.2.2 Stockpile Sustainment

Stockpile Sustainment directly executes maintenance, surveillance, assessment, surety, and management 

activities for all enduring weapons systems in the stockpile. The program includes the B61, W76, W78, 

W80, B83, W87, and W88 Stockpile Systems as well as Multi-Weapon Systems.
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The budget request for Stockpile Sustainment decreased, reflecting:

◼ W78 completion of detonator cable production and W78 Integrated Surety Architecture scope 

shifting out of the current FYNSP

◼ W80 completion of Multi-Application Transportation Attachment Devise qualification activities 

and surveillance activities

◼ B83 reduced program requirements per National Security Memorandum

◼ W88 Alt 940 project transition from development to initial system-level production

These decreases are partially offset by increases in the B61, W76, W87, and Multi-Weapon Systems for 

development, procurement, and surveillance activities. 

8.4.2.3 Weapons Dismantlement and Disposition

Weapons Dismantlement and Disposition dismantles retired weapons and dispositions retired 

components from the stockpile. It also provides safety studies on retired systems and technical analysis 

needed to dismantle, and safely store, weapons being removed from the stockpile. It provides an 

integrated program to safely dismantle and dispose of weapon components that have been retired, while 

some limited number of components from the dismantled weapons are preserved for potential reuse in 

stockpile modernization and safety testing programs.

The budget request for Weapons Dismantlement and Disposition decreased slightly, reflecting a slight 

ramp-down in dismantlement of components.

8.4.2.4 Production Operations

Production Operations is a multi-weapon system, manufacturing-based program that sustains individual 

site production capabilities and capacity for the stockpile sustainment and modernization programs, 

including limited life component production and weapon assembly and disassembly operations. 

Production Operations also provides programmatic equipment maintenance, and 

maintenance/calibration services for manufacturing operations to meet DoD War Reserve requirements. 

The budget request for Production Operations increased to support:

◼ Base capability support for Power Sources and Energetics and the Mark Quality Manufacturing 

Center

◼ New Brunswick Laboratory Operations

◼ NNSA Enterprise Capacity Modeling

◼ Continued hiring of critical skilled labor resources to support increase in production activities

8.4.2.5 Nuclear Enterprise Assurance

The FY 2024 budget request continues funding for this subprogram, first funded in FY 2023, that actively 

manages adversarial subversion risks to nuclear weapons and associated design, production, and testing 

capabilities. NEA enables the secure use of digital technologies in the modernization of weapons, 

facilities, and engineering capabilities by preventing, detecting, and mitigating the consequences of

potential subversion. Through nuclear weapon digital assurance, NEA enables risk-managed adoption of 

leading-edge technologies to meet emerging military requirements and to reduce modernization 

schedules and costs.

The budget request for NEA increased, reflecting the ramp-up of NEA as it grows into an established 

program.
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8.4.3 Key Milestones

DOE/NNSA plans include the following key Stockpile Management milestones in Figure 8–2

2

to sustain 

and modernize the stockpile. There were two changes from last year’s plan:

◼ The FY 2030 milestone, Deliver FPU of the W87-1 Modification Program, is shifted to a FY 2031 to 

FY 2032 with Nuclear Weapons Council approval based on the Weapon Design Cost Report and 

schedule risk analysis.

◼ Delivery of the new W93 Warhead was removed from the shaded box, and the new milestone, 

Deliver FPU of the new W93 Warhead, was added to FY 2034 to FY 2036.

One milestone from last year’s Stockpile Stewardship and Management Plan (SSMP) anticipated to be 

completed in FY 2023 is Begin Phase 6.4 activities for the W80-4 LEP.

Figure 8–2. Key milestones for Stockpile Management

8.5 Production Modernization

The Production Modernization program is responsible for modernizing the facilities, infrastructure, and 

equipment that produce materials and components to meet stockpile requirements and maintain the 

Nation’s nuclear deterrent. It consists of five major subprograms: (1) Primary Capability Modernization,

(2) Secondary Capability Modernization, (3) Tritium and Domestic Uranium Enrichment, (4) Non-Nuclear 

Capability Modernization, and (5) Capability-Based Investments (CBI).

8.5.1 Budget

The budget request for Production Modernization increased 8.6 percent from the FY 2023 enacted budget

and is illustrated in Figure 8–3.

2 These key milestones do not include key annual deliverables, such as completing the Annual Assessment Process culminating in 

the national security laboratory (Los Alamos National Laboratory [LANL], Lawrence Livermore National Laboratory [LLNL], and 

Sandia National Laboratories [SNL]) Directors’ letters to the Secretaries of Energy and Defense by the end of each FY; meeting 

Surveillance Program requirements as approved via the surveillance governance model; and updating system reliability estimates 

and issuing a Weapons Reliability Report.
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Figure 8–3. Fiscal year 2024 President’s Budget Request for Production Modernization3

8.5.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023

Enacted Budget

8.5.2.1 Primary Capability Modernization

Primary Capability Modernization consolidates management of primary stage material processing and 

component production capabilitiesin the nuclear security enterprise. The program includes (1) Plutonium 

Modernization and (2) High Explosives and Energetics (HE&E) Modernization. The Plutonium program 

includes Los Alamos Plutonium Pit Production Project (LAP4), Technical Area (TA)-55 Reinvestment Project 

Phase 3, Transuranic Liquid Waste Facility, Chemistry and Metallurgy Research Replacement project, and 

the Savannah River Plutonium Processing Facility (SRPPF). The HE&E program includes the Energetic 

Materials Characterization Facility, the High Explosives (HE) Synthesis, Formulation, and Production 

project, and the HE Science and Engineering Facility. 

The budget request for the Primary Capability Modernization program decreased due to the use of 

carryover funding for SRPPF and the deferral of the High Explosive Synthesis, Formulation, and Production 

3 Warhead Assembly is not yet a subprogram of Production Modernization. It is proposed to provide Other Project Costs funding 

to develop production modernization strategies for material staging and warhead assembly operations at Pantex. Other Projects 

Costs include costs associated with planning and development, generic research and development, operations support, and onetime startup costs.
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Facility (HESFP) and Energetic Materials Characterization (EMC) projects. Given capacity constraints at 

both Los Alamos National Laboratory (LANL) and the Pantex Plant (Pantex), the FY 2024 budget proposes 

to defer HESFP and EMC to ensure higher priority projects (SRPPF and LAP4) have the necessary staffing 

to maintain schedules. However, the budget requests increased for activities associated with Los Alamos 

Plutonium Operations, LAP4, and Savannah River Plutonium Operations.

8.5.2.2 Secondary Capability Modernization

Secondary Capability Modernization restores and increases manufacturing capabilities for the secondary 

stage of nuclear weapons in the nuclear security enterprise. This modernization includes ensuring the 

availability of strategic materials and other sub-component streams necessary for the secondary stage, as 

well as modernizing the facilities and operations required to process these materials, fabricate them into 

parts, and assemble the final components. The program includes several subprograms: (1) Uranium 

Modernization, including the Uranium Processing Facility; (2) Depleted Uranium Modernization; and 

(3) Lithium Modernization, including the Lithium Processing Facility. 

The budget request for Secondary Capability Modernization increased to support construction of the 

Uranium Processing Facility.

8.5.2.3 Tritium and Domestic Uranium Enrichment

Tritium and Domestic Uranium Enrichment (DUE) consist of two parts: (1) Tritium Sustainment and 

Modernization, which produces, recovers, and recycles tritium to support national security requirements,

and includes the Tritium Finishing Facility project, and (2) the DUE Program, which is responsible for

providing unobligated, low-enriched uranium for tritium production, and preserving and advancing

uranium enrichment technology for potential future deployment to meet national security needs. 

The budget requests for Tritium and DUE increased to support:

◼ Labor and material purchases for DUE centrifuge development as the program advances towards 

larger-scale R&D demonstrations

◼ Initiation of design activities for a DUE Pilot Plant

These increases are partially offset by the proposed deferral of the Tritium Finishing Facility project to 

prioritize SRS design and construction capacity for the SRPPF project.

8.5.2.4 Non-Nuclear Capability Modernization

Non-Nuclear Capability Modernization consolidates management and oversight of strategic investments 

to modernize the extensive suite of infrastructure and equipment required to support the non-nuclear 

component lifecycle inclusive of design, development, qualification, production, and surveillance. This

program is responsible for all non-nuclear components external to the primary or secondary stage in the 

nuclear explosive package. It also includes the Power Sources Capability line-item.

The budget request for this program increased to support:

◼ Equipment procurement for the Kansas City National Security Campus (KCNSC) expansion efforts

◼ Modernization of equipment to develop and produce trusted radiation-hardened 

microelectronics at Sandia National Laboratories (SNL)

◼ A return to project execution for Power Sources Capability, which took a temporary pause to 

evaluate scope and cost options
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8.5.2.5 Capabilities-Based Investments 

The CBI program executes projects to replace or enhance core enterprise capabilities through 

recapitalization of high risk of failure test, measurement, and production equipment. CBI addresses 

enduring, multi-program requirements through discrete, short-duration projects. These investments 

recapitalize scientific and manufacturing capabilities that have degraded due to aged, broken, or outdated 

equipment and supporting systems. CBI activities primarily involve capital equipment purchases and 

minor construction projects that ensure needed capabilities are available for stockpile stewardship, 

sustainment, and modernization. 

The budget request for this program did not change significantly.

8.5.3 Key Milestones

Key milestones for Production Modernization are presented by program in Sections 8.5.3.1–8.5.3.5.

8.5.3.1 Primary Capability Modernization

Key milestones for Primary Capability Modernization are in Figure 8–4. Major changes from last year’s 

plan related to Primary Capability Modernization are: 

◼ The FY 2023 milestone, Obtain Critical Decision (CD)-1 for Energetic Materials Characterization, is 

delayed to FY 2027 due to reprioritization across the Production Modernization construction 

portfolio, recognizing the nuclear security enterprise’s capacity to execute construction and 

maintaining a focus on finishing projects currently under construction.

◼ The FY 2023 milestone, Obtain FPU for pit production at LANL, is delayed to FY 2025 to incorporate 

design changes.

◼ The FY 2024 milestone, Obtain CD-2/3A for SRPPF, is renamed Obtain CD-2/3 for SRPPF and is 

delayed to FY 2025 to reflect the risk-informed schedule estimate.

◼ The FY 2024 milestone, Achieve 10 pits per year production capability at LANL, is removed as new 

metrics for interim milestones are under development.

◼ The FY 2026 milestone, Achieve 30 pits per year production capability at LANL, is delayed to 

FY 2028 based on the LAP4 30 Base subproject individual equipment schedules as well as updated

LANL program schedules.

◼ The FY 2030 milestone, Obtain CD-4 for High Explosives Synthesis, Formulation, and Production, 

is delayed to FY 2034 due to reprioritization across the Production Modernization construction 

portfolio, recognizing the nuclear security enterprise’s capacity to execute construction and 

maintaining a focus on finishing projects currently under construction.

◼ The FY 2027 milestone, Obtain CD-4 for High Explosives, Science, and Engineering, is delayed to 

FY 2028 due to a delay associated with the rebid and replan for CD-3A work after termination of 

the early works contractor and due to a required redesign for the HE Lab Blast Wall.

◼ The FY 2028 milestone, Obtain CD-4 for LAP4, covers all LAP4 subprojects and is delayed to 

FY 2031 due to the approved LAP4 30 Base subproject performance baseline. 

◼ The FY 2030 milestone, Obtain CD-4 for Energetic Materials Characterization, is delayed to 

FY 2034 due to reprioritization across the Production Modernization construction portfolio, 

recognizing the nuclear security enterprise’s capacity to execute construction and maintaining a 

focus on finishing projects currently under construction.
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◼ There is one new milestone: Procure first lot of TATB (triaminotrinitrobenzene) from the Naval 

Surface Warfare Center Indian Head Division prototype manufacturing facility in FY 2026.

One milestone from last year’s SSMP, Obtain CD-2/3 for LAP4 30 base equipment, was completed in 

FY 2023.

Figure 8–4. Key milestones for Primary Capability Modernization

8.5.3.2 Secondary Capability Modernization

Key milestones for Secondary Capability Modernization are in Figure 8–5. Major changesto the Secondary 

Capability Modernization milestones from last year’s SSMP are:

◼ The FY 2023 milestone, Obtain CD-4 for Y-12 Calciner project, is delayed to FY 2026 due to delays 

in receiving equipment from the fabrication vendor.

◼ The milestones, Obtain CD-0 for Depleted Uranium Manufacturing Capability and Obtain CD-1 for 

Depleted Uranium Manufacturing Capability, are removed. The program is currently conducting 

an Analysis of Alternatives and evaluating a phased and modular approach to achieve this new 

capability.

◼ The FY 2023 milestone, Obtain CD-4 for Y-12 electrorefiner, is delayed to FY 2024 due to 

inadequate chilled water supply and the need for component replacement.

◼ The FY 2027 milestone, Obtain CD-4 for Uranium Processing Facility, is delayed to 2029 due to 

contractor performance that was below expectations, direct and indirect impacts from the 

Coronavirus Disease 2019 pandemic, and labor availability and procurement costs. The project is 

undergoing a Federal re-baseline.
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Two milestones from last year’s SSMP are anticipated to be completed in FY 2023:

◼ Obtain CD-3A for Lithium Processing Facility

◼ Achieve technology readiness level 5 for Cold Hearth Melting

Figure 8–5. Key milestones for Secondary Capability Modernization4

8.5.3.3 Tritium and Domestic Uranium Enrichment

Key milestones for Tritium and DUE are shown in Figure 8–6. Major changes from last year’s plan related 

to Tritium and DUE are:

◼ The FY 2023 milestone, Complete facility modifications to prepare for future demonstration of the 

ORNL small centrifuge, is delayed to 2024 due to a 1-month delay that pushes the project into the 

first quarter of FY 2024.

◼ The FY 2025 milestone, Reliably produce a total of 3,300 grams of tritium using two TVA reactors 

over their 18-month cycles, and the FY 2027 milestone, Reliably extract 3,300 grams of tritium

from TPBARS available at SRS, are changed to ... 2,800 grams of tritium... due to prioritizing other 

Production Modernization scope.

◼ The FY 2029 through FY 2031 milestone, Obtain CD-4 for Tritium Finishing Facility, is delayed until 

FY 2033 through FY 2035 due to capacity constraints at Savannah River Site (SRS) and the need to 

prioritize SRPPF. The current facility will remain operational, supplying tritium-filled reservoirs to the 

Department of Defense (DoD) until the Tritium Finishing Facility is operational.

◼ The FY 2026 milestone, Increase yearly extractions at Tritium Extraction Facility from one to eight, 

is renamed Increase extractions at Tritium Extraction Facility from one to eight in a single FY for 

clarity, and is delayed to FY 2029. Eight extractions in a 12-month period were demonstrated 

between 2022 and 2023, but eight extractions in a single FY are not planned until FY 2029.

◼ The FY 2026 milestones, Obtain CD-3A for Tritium Finishing Facility and Obtain CD-2/3 for Tritium 

Finishing Facility, are removed. With the proposed deferral, NNSA is re-working the schedule for 

interim milestones, and updated dates are not yet available.

4 CD-4 is subject to change since the Uranium Processing Facility is undergoing a Federal re-baseline. 
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Figure 8–6. Key milestones for Tritium Modernization and Domestic Uranium Enrichment

8.5.3.4 Non-Nuclear Capability Modernization

Key milestones for Non-Nuclear Capability Modernization are in Figure 8–7. Major changes from last 

year’s plan are:

◼ The milestones Complete KCNSC Short Term Expansion Plan and Obtain KCNSC Short-term 

Expansion Space are consolidated to Complete KCNSC Short-term Expansion Plan, including all of 

Building 23. The completion date is shifted to FY 2028, reflecting the increased scope of the 

project since NNSA purchased all of Building 23 in February 2023, which expands the project to 

include the North portion of the building as well as the South portion.

◼ The FY 2024 milestone, Finalize design and obtain CD-2/3 for Power Sources Capabilities, is 

delayed to FY 2025 due to a pause taken prior to CD-1 to revisit the conceptual design and identify 

opportunities for cost avoidance.

◼ The FY 2026 milestone, Obtain CD-4 for Power Sources Capability, is delayed to FY 2030 due to a 

pause taken prior to CD-1 to revisit the conceptual design and identify additional savings.

◼ The FY 2023 milestone, Obtain CD-0 for Microelectronic Component Capabilities (previously 

named Microelectronics HiFac), and the FY 2037 milestone, Obtain CD-4 for Microelectronic 

Component Capabilities, are removed. A planning study to determine the best means of 

addressing the current gap in microelectronic component capability is underway and is expected 

to be completed in FY 2023.

Figure 8–7. Key milestones for Non-Nuclear Capability Modernization
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8.5.3.5 Capability-Based Investments

CBI does not have its own milestones since its numerous, relatively low-cost, short-duration projects, 

enable activities that support other programs’ milestones.

8.6 Stockpile Research, Technology, and Engineering

Stockpile Research, Technology, and Engineering (SRT&E) program provides the knowledge and expertise 

needed to maintain confidence in the nuclear stockpile without additional nuclear explosive testing. 

SRT&E encompasses five major subprograms: (1) Assessment Science, (2) Engineering and Integrated 

Assessments, (3) Inertial Confinement Fusion (ICF), (4) Advanced Simulation and Computing (ASC), and 

(5) Weapon Technology and Manufacturing Maturation. Academic Programs was previously a 

subprogram of SRT&E, but starting in FY 2024, funding for this program is requested apart from SRT&E 

under the new Academic Programs and Community Support line item; please refer to Section 8.8.2 for 

budget information and Chapter 7, “Workforce,” for details about grants and scholarships.

8.6.1 Budget

The budget request for SRT&E increased 8.4 percent from the FY 2023 enacted budget and is illustrated 

in Figure 8–8. 

Figure 8–8. Fiscal year 2024 President’s Budget Request for Stockpile Research, Technology, and 

Engineering
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8.6.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 

Enacted Budget

8.6.2.1 Assessment Science

Assessment Science provides the knowledge and expertise needed to maintain confidence in the nuclear 

stockpile in the absence of nuclear explosive testing. The program is comprised of six subprograms: 

(1) Primary Assessment Technologies, (2) Dynamic Materials Properties, (3) Advanced Diagnostics, 

(4) Secondary Assessment Technologies, (5) Enhanced Capabilities for Subcritical Experiments (ECSE), and 

(6) Hydrodynamic and Subcritical Experiment Execution Support. The line-item construction projects U1a 

Complex Enhancements Project and Z-pinch Experimental Underground System Testbed Facilities 

Improvement are also contained within this program.

The budget request for Assessment Science increased to fully fund the Z-pinch Experimental Underground 

System Testbed Facilities Improvement project while continuing to support mission-critical activities at 

Joint Actinide Shock Physics Experimental Research, National Ignition Facility, TA-55 gas gun, and requisite 

plutonium shots on Z.

8.6.2.2 Engineering and Integrated Assessments

Engineering and Integrated Assessments is responsible for developing the foundational technologies and 

enterprise capabilities underpinning warhead survivability. These technologies and capabilities are 

matured and developed from a system agnostic perspective until a warhead’s response to the 

stockpile-to-target sequence is understood, ensuring a responsive nuclear deterrent through 

collaborative partnerships, proactive integration, and assessments. This program includes seven 

subprograms: (1) Archiving and Support, (2) Delivery Environments, (3) Weapons Survivability, (4) Studies 

and Assessments, (5) Aging and Lifetimes, (6) Stockpile Responsiveness, and (7) Advanced Certification 

and Qualification. The Combined Radiation Environments for Survivability Testing line-item project also 

resides within this program.

The budget request increase for Engineering and Integrated Assessments reflects programmatic growth 

in the Aging and Lifetimes, Archiving and Support, Delivery Environments, Studies and Assessments, 

Advanced Certification and Qualification, and the Stockpile Responsiveness Program.

8.6.2.3 Inertial Confinement Fusion

ICF provides high energy density (HED) science capabilities and expertise that support research and testing 

across the breadth of stockpile stewardship. Its two-fold mission is to meet immediate, and emerging,

HED science needs to support the deterrent of today and to advance the R&D capabilities necessary to 

meet those needs for the deterrent of the future. The program includes three subprograms: (1) HED and 

Ignition Science for Stockpile Applications, (2) ICF Diagnostics and Instrumentation, and (3) Facility 

Operations.

The budget request for ICF decreased, reflecting programmatic prioritization of experimental campaigns 

and the most important maintenance activities.

8.6.2.4 Advanced Simulation and Computing

ASC provides high-end simulation capabilities (e.g., modeling codes, computing platforms, and supporting 

infrastructure) to meet stockpile stewardship requirements. ASC provides the weapon codes that provide 

the integrated assessment capability supporting annual assessment, future sustainment program 

qualification and certification of warheads on entry into the stockpile. The program includes five 

subprograms: (1) Integrated Codes, (2) Physics and Engineering Models, (3) Verification and Validation,

(4) Computational Systems and Software Environment, and (5) Facility Operations and User Support. The 
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Advanced Technology Development and Mitigation subprogram is being stood down since it will have 

achieved the NNSA Exascale Computing Project objectives at end of FY 2023.

The decrease in the budget request for ASC prioritizes facility upkeep, code modernization, and system 

recapitalization, while continuing to support increased simulation workloads for the nuclear weapons 

mission and the operation of El Capitan and Crossroads. It also reflects the standdown of the Advanced 

Technology Development and Mitigation subprogram with the deployment of the El Capitan exascale 

system.

8.6.2.5 Weapon Technology and Manufacturing Maturation

Weapons Technology and Manufacturing Maturation is responsible for developing agile, affordable, 

assured, and responsive technologies and capabilities for nuclear stockpile sustainment and 

modernization to enable the future success of the nuclear security enterprise. It is comprised of three 

subprograms: (1) Surety Technologies, (2) Weapon Technology Development, and (3) Advanced 

Manufacturing Development.

The budget request for Weapons Technology and Manufacturing Maturation increased to support:

◼ Technologies that develop novel manufacturing methods, novel materials, and improve the 

component design process, ensuring the complex remains responsive and able to address 

increased demands from the growing number of potential weapon systems

◼ Maturation of several key technologies that are new to the weapons complex

8.6.3 Key Milestones

The Stewardship Capability Delivery Schedule is used to align SRT&E programs with mission objectives, 

coordinate efforts across Defense Programs, and communicate with internal and external stakeholders.

Other high-level planning activities, such as the National Plutonium Aging Science Plan, serve as vehicles 

for coordinating work in specific areas of mission need. Key milestones for SRT&E are illustrated in 

Figure 8–9. Major changes from last year’s plan are:

◼ The FY 2023 milestone, Design and demonstrate a light weight, modular weapon system 

architecture, is delayed to FY 2024 due to challenges with staffing and supply chain delivery times.

◼ The FY 2024 milestone, Evaluate and implement re-entry concepts/environments within the HOT 

SHOT initiative, is renamed, Evaluate and implement re-entry concepts/environments using 

technology maturation demonstrators for future stockpile systems to better reflect use of 

demonstrator systems.

◼ The FY 2024 milestone, Field a neutron source and detectors on an Excalibur experiment (ECSE 

reactivity), is delayed to FY 2027 because it relies on the Z-pinch Experimental Underground 

System Testbed Facilities Improvement project, which requires additional tunneling and was 

converted to a line-item construction project. Additionally, this milestone is renamed Field a 

neutron source and detectors on an Excalibur experiment (ECSE reactivity) for clarity since 

Excalibur will be the first subcritical experiment campaign demonstrating this new measurement 

capability. This capability will then be applied to the plutonium aging mission during the followon Durandal campaign. The milestone, Execute Excalibur Experiment (ECSE reactivity), is removed 

since it is addressed by this renaming.

◼ The FY 2024 milestone, Execute Excalibur Experiment (ECSE reactivity), is removed since it is 

redundant with the milestone Field a neutron source and detectors to obtain subcritical 

experiments reactivity measurements.
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◼ The FY 2026 milestone, Complete Red Sage & Nimble subcritical experiment campaigns, is delayed 

to FY 2027 due to an updated subcritical experiments schedule.

◼ The FY 2027 milestone, Obtain CD-4 for Advanced Sources and Detectors Scorpius, is delayed to 

FY 2030 due to updated baseline upon achieving CD-2/3 in November 2022.

◼ The FY 2028 milestone, Execute Sherman Experiment (ECSE plutonium radiograph), is delayed to 

FY 2030 since it requires CD-4 for Advanced Sources and Detectors Scorpius.

One milestone from last year’s SSMP is anticipated to be completed in FY 2023: Accept Advanced 

Technology System-3/Crossroads Phase 1 computing platform.

Figure 8–9. Key milestones for Stockpile Research, Technology, and Engineering

8.7 Infrastructure and Operations

Infrastructure and Operations maintains, operates, and modernizes DOE/NNSA’s infrastructure in a safe, 

secure, and cost-effective manner to support all DOE/NNSA programs. Infrastructure and Operations 

takes a comprehensive approach to modernizing DOE/NNSA’s infrastructure while maximizing return on 

investment, enabling program results, and reducing enterprise risk. The program also plans, prioritizes, 

and constructs mission-enabling facilities and infrastructure. Infrastructure and Operations includes 

(1) Operations of Facilities, (2) Safety and Environmental Operations, (3) Maintenance and Repair of 

Facilities, (4) Recapitalization, and (5) Line-Item Construction. Additional information about 

Infrastructure and Operations can be found in Chapter 6, “Infrastructure and Operations.”

8.7.1 Budget

The budget request for Infrastructure and Operations increased 6.3 percent from the FY 2023 enacted 

budget and is illustrated in Figure 8–10.
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Figure 8–10. Fiscal year 2024 President’s Budget Request for Infrastructure and Operations

8.7.2 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023

Enacted Budget

8.7.2.1 Operations of Facilities

Operations of Facilities provides the funding required to operate DOE/NNSA facilities in a safe and secure 

manner and is fundamental to achieving DOE/NNSA’s plutonium, uranium, tritium, lithium, HE, and other 

mission objectives. This program includes essential support, such as water and electrical utilities, safety 

systems, lease agreements, and activities associated with Federal, state, and local environmental, worker 

safety, and health regulations. 

The budget request for Operations of Facilities increased to support:

◼ Operating funds for the Plutonium mission, including the production of at least 30 pits per year 

(ppy) at LANL and the re-establishment of the Waste Characterization, Reduction, and 

Repackaging Facility as a Hazard Category 3 nuclear facility

◼ NNSA’s direct-funded share of operations and utilities for Savannah River National Laboratory

facilities 

◼ Waste activities at the Y-12 National Security Complex due to the resumption of waste shipments

The increase is partially offset by an adjustment to reduce uncosted balances.
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8.7.2.2 Safety and Environmental Operations

Safety and Environmental Operations provides DOE’s Nuclear Criticality Safety Program, Nuclear Safety 

Research and Development, Packaging subprogram, Long Term Stewardship subprogram, and Nuclear 

Materials Integration subprogram. These activities support safe, efficient operation of the nuclear 

security enterprise by providing safety data, nuclear material packaging, environmental monitoring, and 

nuclear material tracking.

The decrease to the budget request for Safety and Environmental Operations reflects an adjustment to 

reduce uncosted balances.

8.7.2.3 Maintenance and Repair of Facilities

Maintenance and Repair of Facilities provides direct-funded maintenance activities across the nuclear 

security enterprise for the recurring daily work required to sustain and preserve DOE/NNSA facilities in a 

condition suitable for their designated purpose. These efforts include predictive, preventive, and 

corrective maintenance activities to maintain facilities, property, assets, systems, roads, and vital safety 

systems.

The budget request for Maintenance and Repair of Facilities increased to support:

◼ NNSA’s direct-funded share of maintenance for Savannah River National Laboratory facilities

◼ Site critical infrastructure at Nevada National Security Site (NNSS) along the mission corridor, to 

include the power backloop

◼ Global security needs at NNSS for Area 12 Tunnel Complex, Radiological/Nuclear 

Countermeasures Test and Evaluation, and Desert Rock Airstrip

◼ Maintenance of the new John M. Googin Technology Development Facility for special materials 

and the repair needs for key high-risk projects at the Y-12 National Security Complex, to include 

the site-wide brine system, the West-End facility treatment tanks, and site potable water tower 

control systems

The increase also reflects the realignment of scope for the maintenance of DOE-owned, Federal Field 

Office space from Federal Salaries and Expenses to Infrastructure and Operations.

8.7.2.4 Recapitalization

Recapitalization modernizes DOE/NNSA’s infrastructure by prioritizing investments, including acquisition 

of new facilities, to improve the condition and extend the life of structures, capabilities, and systems, 

thereby improving the safety and quality of the workplace. Recapitalization addresses obsolete support 

and safety systems; revitalizes facilities that are beyond their design life; and improves the reliability, 

efficiency, and capability of infrastructure to meet mission requirements. Recapitalization investments 

help achieve operational efficiencies and reduce safety, security, environmental, and program risk. The 

Recapitalization program includes minor construction projects, real property purchases, planning, other 

project costs for Infrastructure and Operations-funded mission enabling infrastructure, and deactivation 

and disposal of excess infrastructure. 

The budget request for Recapitalization increased to support: 

◼ The Kansas City Non-nuclear Expansion Transformation plan

◼ Deactivation and disposal of excess infrastructure, including stabilization and risk reduction 

activities at high-risk facilities

◼ Addition of general contract support for construction project management
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The increase also reflects the realignment of scope for the acquisition, sustainment, and disposal of 

DOE-owned, Federal field office space from Federal Salaries and Expenses to Infrastructure and 

Operations.

8.7.2.5 Mission Enabling Construction

These line-item projects will replace obsolete, unreliable facilities and infrastructure to reduce safety and 

program risk while improving responsiveness, capacity, and capabilities. NNSA uses a prioritization 

methodology for mission enabling line-item construction that evaluates investments on closing mission 

gaps, reducing infrastructure risk and safety risk, improving sustainability, and reducing deferred 

maintenance. Programmatic construction line-items fall under the respective programs.

The budget request for Mission Enabling Construction includes funding in FY 2024 for:

◼ TA-46 Protective Force Facility project at LANL

◼ Plutonium Production Building project at LANL

◼ Analytic Gas Laboratory project at the Pantex

◼ Transition to construction for Electrical Power Capacity Upgrade project LANL

Additional information on planned line-item investments can be found in Chapter 6, “Infrastructure and 

Operations.”

8.7.3 Key Milestones

Key milestones for Programmatic Construction are shown in the relevant program sections within this 

chapter, as program mission execution often depends on completion of line-item projects. Schedules for 

the highest priority Programmatic and Mission Enabling project proposals are displayed in Chapter 6, 

Figures 6–6 through 6–13. Projects proposed within the FYNSP have higher-fidelity estimates, and some 

planned projects in the out-years may decide to use alternative strategies other than a line-item project 

once each respective analysis of alternatives is completed.

Per the National Defense Authorization Act for Fiscal Year 2018, DOE/NNSA established the Infrastructure 

Modernization Initiative (IMI) program. Per the National Defense Authorization Act for Fiscal Year 2022, 

Congress amended the IMI to require reducing deferred maintenance (DM) per replacement plant value 

(RPV) by not less than 45 percent by 2030. Baselined against FY 2017 data, the IMI challenges NNSA to 

reach a DM to replacement plant value (DM:RPV) ratio of 2.67 percent by 2030. The IMI will be carried 

out by infrastructure recapitalization, maintenance and repair of facilities, and construction programs. 

The initial plan was transmitted to Congress in September 2018 and an updated plan was delivered in 

October 2022. 

8.7.4 Infrastructure Maintenance and Recapitalization Investments

As part of the IMI, DOE/NNSA is using BUILDER, a system developed by the U.S. Army Corps of Engineers 

and recognized by the National Academy of Sciences as a best-in-class practice for infrastructure 

management. The BUILDER system uses comprehensive inventory, lifecycle, cost, and assessment data 

and risk-informed standards and policies to recommend repairs, and replacements at the most opportune 

time, thus improving DOE/NNSA’s ability to pinpoint and prioritize investments. Historical approaches 

greatly underestimated the RPV of DOE/NNSA’s facilities. Using BUILDER-based calculations provides a 

more accurate and transparent understanding of DOE/NNSA’s infrastructure. The DM costs are tied to 

the RPV since it costs more to repair a more expensive facility; therefore, as expected, DM increased with 

the deployment of the new, more accurate, data-driven approach. The increase in the ratio of DM to RPV 

from FY 2019 to FY 2020 in Table 8–2 was a result of these methodology changes. The overall physical 
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condition of NNSA’s infrastructure did not decline. Notably, the ratio of DM to RPV has steadily decreased 

year-over-year since this change, indicating that recent investments have been successful. As shown in 

Table 8–2, DOE/NNSA’s new calculated RPV is $139 billion, of which $5.1 billion represents excess 

facilities, based on data from the end of FY 2022. In response to Government Accountability Office

recommendations, this information is provided to improve transparency in the budget. 

Table 8–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant 

Value of Active Facilities5

Metric FY 2019 FY 2020 FY 2021 FY 2022

DM $4.8B $5.8B $6.1B $6.5B

RPV $124.3B $116.3B $124.9B $133.9B

DM:RPV Ratio 3.85% 4.99% 4.90% 4.84%

B = billion

DM = deferred maintenance

RPV = replacement plant value

Table 8–3 compares investments in Maintenance and Recapitalization to benchmarks (based on the 

percentage of beginning of the year RPV) derived from the DOE Real Property Asset Management Plan 

and associated guidance. Recapitalization continues to include deactivation and demolition of excess,

and underused, facilities to reduce DOE/NNSA’s footprint. Funding for maintenance has grown 

significantly, but appropriately, over the last several years. This sustained funding level will support 

current maintenance staffing levels to maintain and preserve facilities in a condition suitable to meet an 

increasing mission demand. DOE/NNSA also continues to use targeted asset management programs that 

use supply chain management practices to increase purchasing power for common building components 

across the nuclear security enterprise (e.g., roofs and heating, ventilating, and air conditioning). 

Table 8–3. Projected FY 2024 DOE/NNSA infrastructure maintenance and recapitalization investments

FY 2022 FY 2023 FY2024

RPV ($B) 133.9 134.9 135.9

Maintenance 

Benchmark 

2%–4% RPV

Infrastructure and Safety Maintenance Investments ($K) 700,000 651,617 718,000

Other NNSA Maintenance Investments (direct and indirect funded) ($K) 313,295 310,577 343,743

Total NNSA Maintenance Investments ($K) 1,013,295 962,194 1,061,743

Maintenance as % RPV 0.76% 0.71% 0.78%

Recapitalization 

Benchmark 

1%

Infrastructure and Safety Recapitalization Investments ($K) 600,000 561,663 650,012

Other NNSA Recapitalization Investments ($K) 427,956 474,459 500,503

Total NNSA Recapitalization Investments ($K) 1,027,956 1,036,122 1,150,515

Recapitalization as % RPV 0.77% 0.77% 0.85%

RPV = Replacement Plant Value

$B = billion dollars

$K = thousand dollars

5 DM and RPV totals exclude excess facilities and include KCNSC leased facilities.
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8.8 Other Weapons Activities

8.8.1 Budget

The funding schedule for Other Weapons Activities is illustrated in Figure 8–11.

Figure 8–11. Fiscal year 2024 President’s Budget Request for Other Weapons Activities

8.8.2 Academic Programs and Community Support

This program, formerly a subprogram within the SRT&E portfolio, enables robust and diverse science, 

technology, engineering, and mathematics (STEM) research for educational communities through a 

variety of methods of support. This budget structure change enables improved program integration, 

agility, development, and alignment to critical workforce needs. Academic Programs and Community 

Support is made up of eight subprograms: (1) Stewardship Science Academic Alliance, (2) Minority Serving 

Institution Partnership Program, (3) Tribal Education Partnership Program, (4) Joint Program in High 

Energy Density Laboratory Plasmas, (5) Computational Science Graduate Fellowship, (6) Predictive Science 

Academic Alliance Program, (7) Pipeline Development, and (8) Community Capacity Building Program. 

Pipeline Development and Community Capacity Building Program are new subprograms proposed for 

FY 2024.

8.8.2.1 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted Budget

In FY 2023, Academic Programs was funded as a subprogram of SRT&E. With the change from subprogram 

to program, the budget request for Academic Programs and Community Support increased 36.1 percent 

from FY 2023.
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8.8.2.2 Key Milestones

Academic Programs and Community Support does not have its own milestones since it focuses on 

long-term investments in academic consortia and fellowships to provide relevant research and build a 

pipeline of talent to support the nuclear security enterprise.

8.8.3 Secure Transportation Asset

Secure Transportation Asset (STA) provides safe, secure transport of the Nation’s nuclear weapons, 

weapon components, and special nuclear material throughout the nuclear security enterprise. STA

includes two subprograms: (1) Operations and Equipment and (2) Program Direction. Operations and 

Equipment provides the transportation service infrastructure required for STA to meet DOE/NNSA’s 

nuclear security activities. Program Direction provides salaries, travel, and other related expenses for 

Federal Agents and the secure transportation workforce.

8.8.3.1 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted Budget

The budget request for STA increased 3.7 percent from FY 2023, driven by an increased budget request 

for Operations and Equipment to support Mobile Guardian Transporter schedule deliverables, including:

◼ Test Article 2 Head-On Crash Test

◼ Continued development of Engineering Releases Pre-Production Unit Assembly

◼ Continued Pre-Production Unit stage builds Production Readiness Review

◼ Beginning Advanced Engineering Releases and Post-Crash Test reports

The budget request for Program Direction decreased to account for carryover since there are fewer 

Federal Agents due to two cancelled Nuclear Material Courier Basic courses in FY 2020-2021.

8.8.3.2 Key Milestones

Aging transportation assets must be replaced to meet, and maintain, convoy safety and security 

requirements. The STA milestones in Figure 8–12 will enable DOE/NNSA to support evolving 

transportation requirements for the current and future stockpile.

There were no milestones in last year’s SSMP scheduled for completion in FY 2023.

Figure 8–12. Key milestones for Secure Transportation Asset

8.8.4 Defense Nuclear Security

DOE/NNSA missions must be carried out in a secure environment protected by safeguards and security 

personnel, layers of physical security systems and technology, and sophisticated cybersecurity systems. 

Defense Nuclear Security (DNS) provides protection across the nuclear security enterprise for DOE/NNSA 

personnel, facilities, nuclear weapons, and materials from a full spectrum of threats, ranging from minor 
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security incidents to acts of terrorism. The West End Protected Area Reduction (WEPAR) line-item project 

is also included within DNS.

8.8.4.1 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted Budget

The budget request for DNS increased 16.6 percent from FY 2023 to support: 

◼ Refined security requirements associated with growth across the nuclear security enterprise, 

including plutonium pit production, Kansas City expansion efforts, and the Uranium Processing 

Facility

◼ The transfer of all Safeguards and Security scope to the M&O Contractor Partner at the NNSS

◼ Funding the WEPAR project above the CD-2/3 Total Project Cost, which is needed to address 

issues experienced with delays in projects outside WEPAR’s scope as well as contractor 

performance issues within the WEPAR project

8.8.4.2 Key Milestones

The Security Infrastructure Revitalization Program refreshes aging security infrastructure across the 

enterprise based on a long-range plan that is modified periodically based on DOE/NNSA’s budget, mission, 

and needs.

The DNS milestones in Figure 8–13 are directly linked to modernization of the national security 

infrastructure and will assure that DOE/NNSA mission requirements for the current and future stockpile 

are carried out in a safe and secure environment. There were two changes from last year’s plan:

◼ The FY 2023 milestone, Complete Caerus development, is shifted to FY 2024 due to an 11-month 

delay in receiving network hardware due to supply chain challenges.

◼ The FY 2027 milestone, Complete critical Security Infrastructure Revitalization Program (SIRP)

priorities is removed to better reflect the SIRP projects occurring at multiple sites. Site-specific 

information on SIRP projects is in Section 5.2 Defense Nuclear Security, Section 6.4.2 Defense 

Nuclear Security Minor Construction Investment, and the classified annex.

Figure 8–13. Key milestones for Defense Nuclear Security6

6 The FY 2025 milestone, Complete Y-12 WEPAR, PIDAS modernization, and entry control facility upgrade, is subject to revision 

with the forthcoming project re-plan, as noted in the FY 2024 Construction Project Data Sheet.
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8.8.5 Information Technology and Cybersecurity

The DOE/NNSA Office of the Associate Administrator for Information Management and Chief Information 

Officer supports information management, information technology (IT), and cybersecurity services and 

solutions to help meet security challenges. IT and Cybersecurity program provides a set of capabilities 

that enable the mission by increasing organizational efficiency, protecting information assets, enhancing

communication with internal and external partners, ensuring continuous monitoring, and supporting

effective incident response. This program funds ongoing operations and invests in improvements across 

the nuclear security enterprise to meet the requirements of Executive Order 14028, Improving the 

Nation’s Cybersecurity.

8.8.5.1 Fiscal Year 2024 Budget Request Compared to Fiscal Year 2023 Enacted Budget

The budget request for IT and Cybersecurity increased 29.8 percent from FY 2023 to support:

◼ Investments in cybersecurity tools and services provided to the enterprise

◼ Workforce growth

◼ Technology modernization investments for critical classified and unclassified systems

8.8.5.2 Key Milestones

The milestones in Figure 8–14 are necessary steps toward achieving a modernized IT infrastructure and 

cybersecurity posture for the nuclear security enterprise. There were no changes to last year’s plan, and 

there were no milestones in last year’s SSMP scheduled for completion in FY 2023.

Figure 8–14. Key milestones for Information Technology and Cybersecurity

8.8.6 Legacy Contractor Pensions and Settlement Payments

Starting in FY 2022, Legacy Contractor Pensions and Settlement Payments includes funding to reimburse 

the University of California for a portion of a settlement reached in 2019 with former University of 

California employees of Lawrence Livermore National Laboratory (LLNL) related to health care plans, as 

well as funding for DOE/NNSA’s share of the unfunded liability of the Savannah River Nuclear Solutions 

pension plan. This budget line also continues to include the Weapons Activities share of the DOE’s annual 

reimbursement made to the University of California Retirement Plan for former University of California

employees and annuitants who worked at the LLNL and LANL. 

8.9 Weapons Activities Cost Beyond the FYNSP Period

This section explains the cost estimation methodology that DOE/NNSA uses to create an estimate of the 

aggregate cost of continuing the program described in this SSMP beyond the FYNSP period for which the 

budget request was prepared. This projection is used to evaluate, over a longer timeframe than 

considered in the FYNSP and during programming activities, the total required resources to accomplish
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the program of record, how those resources are allocated, and the overall affordability of the program 

(see Section 8.10).

8.9.1 Basis for Budget Projections

The FY 2024 to FY 2028 FYNSP was generated as part of the DOE/NNSA programming process and reflects

a roll-up of individual estimates developed interactively by Federal Program Managers and DOE/NNSA’s 

M&O partners using historical cost data, current plans for programs and projects, and expert judgment.

The budget estimates for FY 2029 and beyond reflect the costs of continuing the FYNSP program described 

in this SSMP.

Some elements of the Weapons Activities portfolio are assumed to continue beyond the FYNSP at the 

same level of effort as during the FYNSP.7 For these cost projections, such as for Stockpile Sustainment, 

an escalation factor of 2.1 percent was applied. 

Other parts of the program, primarily Stockpile Major Modernization programs and major programmatic 

construction projects, will not proceed at the same level of effort from FY 2029 through FY 2048; they will

instead use funding profiles unique to each project. The estimates and the basis for each of these 

elements of the Weapons Activities portfolio are described in Sections 8.9.2–8.9.3.

8.9.2 Stockpile Major Modernization

Stockpile Major Modernization programs have the goal of extending the lifetime of the nation’s nuclear 

stockpile while addressing required updates and improving their safety and security as possible. Figure 2–2

in Chapter 2, “Stockpile Management,” provides a summary of planned Stockpile Major Modernization 

activities. The nextsections summarize cost estimates for Stockpile Major Modernization programs within 

the current 25-year period. 

8.9.2.1 Cost Estimates across the Phase X/6.X Process

The basis for the cost estimates varies from those using top-down cost models (e.g., analogy comparisons 

to past work completed, parametric relationships, and subject matter expert judgment) to those using 

bottom-up models (e.g., deterministic, unit cost, and activity based). The decision to use the top-down 

cost model versus the bottom-up model is made depending on where the warhead program is in the 

Phase X/6.X Process, reflecting the maturity of the process. Figure 8–15 shows the governing cost 

estimate type for each phase of the Phase 6.X Process and the Phase X Process. DOE/NNSA works in 

conjunction with DoD and M&O partners to develop, refine, and update the estimates throughout these 

processes.

Figure 8–15. Cost estimates across the Phase X/6.X Process

7 Projecting budget estimates for these efforts in this way assumes the continued manageability of whatever risks are present 

during the FYNSP with the same level of effort; this assumption escalates projections for inflation off of the funding level for the 

last year of the FYNSP. A 2.1 percent escalation rate was used.
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The DOE/NNSA OMB Office of Programming, Analysis, and Evaluation develops and publishes major 

modernization planning cost estimates for the SSMP. These cost estimates are initiated at very early 

program maturity, often well before Phase 6.1, Concept Assessment, and are planning estimates for 

alternatives analysis and early programming. These planning estimatesfor Stockpile Major Modernization

assume scopes that are in line with current policy objectives for the modernization effort and updated 

annually for the SSMP.

8

 They are not constrained by future budget availability, and include both warhead 

modernization program (development and production) and non-warhead modernization program

line-item costs that are critical to program success (namely Other Program Money and DoD costs).

9

 These 

cost estimates are used to reflect the anticipated cost of each modernization program in the SSMP until 

the Weapon Design and Cost Report (WDCR) is approved for the effort. The estimate methodology is 

described in more detail in Section 8.9.2.2.

The WDCR is developed by the program teams responsible for the warhead modernization programs and 

provides cost estimates for design, qualification, production, and lifecycle activities. The WDCR includes 

detailed multi-site input and, although primarily performed using a bottom-up approach, may contain 

other methodologies (e.g., parametric, analogous, and subject matter expertise). The WDCR developed 

during Phase 6.2A, Design Definition and Cost Study, is a key input into the Phase 6.2A study report to the 

Nuclear Weapons Council and is required prior to entry to Phase 6.3. Once approved by the Nuclear 

Weapons Council, the WDCR becomes the basis for the Selected Acquisition Report (SAR) to Congress 

required upon entry into Phase 6.3.

The Baseline Cost Report (BCR), which is also developed by the program team, formally updates the WDCR 

based on development and pre-production activities. The BCR is updated based on refined scopes and 

schedule definitions (reflecting the increased maturity of the program) and represents a more definitive 

cost estimate than either the planning estimate or WDCR. The NNSA Administrator approves a program 

baseline, including the BCR, prior to Phase 6.3. The BCR supersedes previous cost estimates and becomes

the program of record, which is transmitted annually to Congress as part of the SAR. 

The DOE/NNSA Office of Cost Estimating and Program Evaluation conducts an independent cost review 

prior to Phase 6.2A, and independent cost estimates prior to entry into Phase 6.3, Phase 6.4, Production 

Engineering, and 6.5, First Production.

8.9.2.2 DOE/NNSA Office of Management and Budget Cost Estimating Methodology

The DOE/NNSA OMB Office of Programming, Analysis and Evaluation planning estimates for Stockpile 

Major Modernization programs are developed in the following manner:

◼ Performed using a “top-down” analogy method that is consistent with early-stage planning10

◼ Informed by ongoing and past program costs (such as the development and production of the 

W76-1, B61-12, W88 Alt 370) and the evaluation of the relative complexities of future systems11

8 The Nuclear Weapons Council approves the specific scope for the weapon modernization program based on the alternatives 

developed during Phase 6.2/2. The cost estimate range used in a planning estimate reflects the uncertainty in implementing a 

single assumed point solution, rather than the range of every possible design solution.

9

In estimating the cost of a warhead modernization program, the weapon programs depend on an adequately funded base of 

other DOE/NNSA capabilities, are incremental to that base, and reflect both each program’s budgeted line-item and increments 

to other critical activities (such as early-stage technology maturation [called Other Program Money]). As the overall program 

integrator, the Federal Program Manager identifies the funding streams needed for the program to be successful.

10 Additional detail on the cost estimating methodology of DOE/NNSA’s planning estimates is in the technical paper, “Planning 

for the Future: Methodologies for Estimating U.S. Nuclear Stockpile Cost” (Lewis et al. 2016; Cost Engineering, 58 [5], pp. 6-12).

11 These program and subject matter experts evaluate the relative scope complexity of the complete W76-1 and near-complete 

B61-12 LEP and W88 Alt 370 compared to each planned future warhead modernization program, which aids in providing a cost 

estimate range based on underlying technical and cost uncertainties.
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◼ Based on time-phased development costs using a standard profile,12 as well as production costs 

using a nonlinear cost growth profile similar to that of the W76-1

◼ Based on technical and programmatic inputs from Federal Program Managers, Federal field 

offices, and subject matter experts across the national security laboratories and nuclear weapons 

production facilities

Cost ranges reflect the underlying technical and modeling uncertainties of the programmatic scope at the 

time. During the early stages of warhead acquisitions (Phases 1/6.1 and 2/6.2), designs may experience 

scope changes due to ongoing down-select decisions regarding threshold and objective requirements, 

which may result in cost changes compared to those reported in previous SSMPs. These ranges will 

typically be greatest for earlier-stage programs and narrow over time. The cost estimates for future 

systems with little design definition are based on the W87-1 and W93 estimates, with an expanded range 

due to uncertainty in scope and quantities and in the escalation rate so far in the future.

8.9.2.3 Current Estimates

Figures 8–16 through 8–20 and Tables 8–4 through 8–12 provide cost estimates for each Stockpile Major 

Modernization program for the next 25 years. Table 8–4 delineates the type of cost estimate for each of 

the warhead modernization programs included in the 25-year plan. Additional details on the basis for 

each estimate are provided for each individual program in Sections 8.9.2.4–8.9.2.9. 

Table 8–4. DOE/NNSA cost estimates for Stockpile Major Modernization Programs13

Stockpile Major Modernization 

Program Type of Cost Estimate Total Estimated Cost (FY 2023 dollars in billions)

Total Estimated Cost

(then-year dollars in billions)

B61-12 LEP BCR/SAR 9.5 8.3

W88 Alteration Program BCR/SAR 3.3 2.8

W80-4 LEP BCR/SAR 11.2 12.3

W87-1 Mod Program WDCR 12.1 15.9

W93 Program Planning Estimate 16.2 22.9

Future Strategic Land-Based Warhead Planning Estimate 15.9 32.4

Future Strategic Sea-Based Warhead Planning Estimate 21.6 37.1

Future Air-Delivered Weapon Planning Estimate 19.3 47.3

Future W76-1/2 Replacement Planning Estimate 23.4 55.1

BCR = Baseline Cost Report

LEP = life extension program

SAR = Selected Acquisition Report

WDCR = Weapon Design and Cost Report

Each Stockpile Major Modernization program section contains a summary table with high, low, and 

nominal (proposed budget or BCR/SAR value) estimates for DOE/NNSA, in constant FY 2023 and then-year 

dollars. Where appropriate, the tables also include pre-SAR values for pre-Phase 6.2 costs. The low 

estimates presented in the tables and shown in graphs as a green line represent the mid-point (50 percent) 

of the cost estimate. The high estimates represent the 85th percent for the B61-12, W88 Alt 370, W80-4, 

W87-1, and W93; the estimate increased to the 90th percent for the future systems to reflect the greater 

uncertainty.

For early-stage programs using planning estimates, the figures and tables reflect the proposed FY 2024

FYNSP budget and, for years beyond FY 2028 the midpoint between the high and low estimates. 

12 Lee, David. The Cost Analyst’s Companion, 3rd ed., McLean, VA: Logistics Management Institute, McLean, VA.

13 For programs pre-phase 1/6.1, the 90th percent value of a representative design and quantity is provided. Tables 8–5 through 

8–13 provide values for a high and low estimate range, in addition to the SAR, WDCR, or planning estimate totals.
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Items to consider when comparing estimates to one another:

◼ The constant-year cost totals in the tables are the most comparable because inflation effects 

become significant over warhead modernization activity timeframes. Consideration should also 

be given to the varying quantities of warheads being refurbished for each system. The FY 2024

SSMP’s classified Annex provides additional information on production quantities.

◼ The then-year planning estimates in the tables and figures are derived from constant-year 

estimates using escalation rates provided in NNSA NAP 413.6. The outyear rate of 2.9% percent 

rate represents an average of the individual site escalation rates. The WDCR and BCR program 

office estimates are developed at the site and component level, and therefore use the escalation 

rates specific to each site and function rather than an average.

◼ Published estimate ranges are meant to reflect the underlying technical and cost uncertainty of 

the assumed scope. Early-stage programs, particularly those before Phase 6.3, may experience 

significant scope changes because the Nuclear Weapons Council may update and/or down-select

design options that significantly impact the work scope and cost estimate.

◼ Only the planning estimates include pre-Phase 6.2 costs. The WDCR and BCR/SAR estimates do 

not include these costs since they are prepared during Phase 6.2 or beyond.

8.9.2.4 B61-12 Life Extension Program Cost Estimate

The B61-12 LEP received authorization to enter Phase 6.5 in FY 2021 and achieved first production unit in 

November 2021. In 2022, the Nuclear Weapons Council formally accepted the B61-12 into the stockpile 

and authorized Phase 6.6, Full-Scale Production. The values for development and production costs in 

Figure 8–16 and Table 8–5 reflect DOE/NNSA’s FY 2020 BCR update issued in November 2020, with an 

overall cost estimate of $8.3 billion (then-year dollars) and are unchanged from last year’s SSMP. The 

B61-12 LEP completed its use of Other Program Money for multi-system production process 

improvements in FY 2022. The costs of these related programs are estimated to be $648 million.

Figure 8–16. B61-12 Life Extension Program cost from fiscal year 2009 to completion
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Table 8–5. Total estimated cost for B61-12 Life Extension Program

FY 2012–FY 2027

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Pre-SAR Cost 0.5 0.4

SAR Total 9.5 8.3

SAR OPM Total 0.8 0.6

Planning Estimate (High)a 9.9 8.8

Planning Estimate (Low)

a 9.3 8.2

OPM = Other Program Money

SAR = Selected Acquisition Report

a Excluding OPM

8.9.2.5 W88 Alteration 370 Cost Estimate

The W88 Alt 370 Program received authorization to enter Phase 6.5 in FY 2021 and completed the July 

2021 first production unit per the baseline schedule. The Nuclear Weapons Council formally authorized 

Phase 6.6 entry in 2022 and accepted the W88 Alt 370 into the stockpile. The current estimate is 

unchanged from the updated BCR issued by DOE/NNSA in September 2020, with an estimate of $2.8 

billion (then-year dollars). The revised BCR was reconciled with the independent cost estimate performed 

by DOE/NNSA’s Office of Cost Estimating and Program Evaluation. The W88 Alt 370 Program is continuing 

to use other DOE/NNSA programs for multi-system production process improvements. The estimated 

costs of these related programs (such as Other Program Money) remain unchanged at $171 million. The 

numbers in Figure 8–17 and Table 8–6 reflect the BCR update.

Figure 8–17. W88 Alteration 370 Program (with conventional high explosive refresh)

from fiscal year 2013 to completion
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Table 8–6. Total estimated cost for W88 Alteration 370 Program 

(with conventional high explosive refresh)

FY 2013–FY 2027

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Pre-SAR Cost 0.1 0.1

SAR Total 3.3 2.8

SAR OPM Total 0.2 0.2

Planning Estimate (High)a 3.3 2.8

Planning Estimate (Low)a 3.2 2.7

OPM = Other Program Money

SAR = Selected Acquisition Report

a Excluding OPM

8.9.2.6 W80-4 Life Extension Program Cost Estimate

In FY 2023, the W80-4 received authorization to enter Phase 6.4, and published its BCR and an update to 

its WDCR. The W80-4 LEP is on track to support fielding the Air Force’s scheduled Long Range Standoff 

cruise missile initial and final operational capability dates. The current cost estimate is displayed in 

Figure 8–18 and Table 8–7. 

Figure 8–18. W80-4 Life Extension Program cost from fiscal year 2015 to completion
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Table 8–7. Total estimated cost for W80-4 Life Extension Program

FY 2015–FY 2032

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Pre-SAR Cost 0.9 0.7

SAR Total 11.2 12.3

SAR OPM Total 0.2 0.2

Planning Estimate (High)a 13.1 14.3

Planning Estimate (Low)

a 11.4 12.3

OPM = Other Program Money

SAR = Selected Acquisition Report

a Excluding OPM

8.9.2.7 W87-1 Modification Program Cost Estimate

In February 2019, the Nuclear Weapons Council authorized a restart of Phase 6.2 activities for the W87-1 

Modification Program, and the program is slated to deploy on the LGM-35A Sentinel in the early 2030s. 

In 2019, the Nuclear Weapons Council reviewed a series of surety architecture design options, to include

detailed risk/benefit and cost analyses, before selecting a single surety option for W87-1 Mod Program. 

DOE/NNSA continues to evaluate other component design options and trades. In FY 2021, the W87-1 

Mod Program completed Phase 6.2 and entered Phase 6.2A. In FY 2023, the W87-1 entered Phase 6.3 

and completed its WDCR, and the associated cost estimate is shown in Figure 8–19. The estimates in 

Figure 8–19 and Table 8–8 do not include costs associated with the production of plutonium pits for the 

W87-1 Mod Program after the capability to produce 30 ppy is demonstrated at LANL and 50 ppy at SRS; 

those costs are contained in Plutonium Modernization.

Figure 8–19. W87-1 Modification Program cost from fiscal year 2019 to completion14

14 The W87-1 WDCR includes both a point estimate and Management Reserve and Contingency at the 20th percent and 80th

percent levels based on risk assessments. The high and low values displayed in this graphic show that uncertainty range.
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Table 8–8. Total estimated cost for W87-1 Modification Program

FY 2019–FY 2037

Dollars in Billions FY 2023 Dollars Then-Year Dollars

WDCR Estimate 12.1 15.9

Planning Estimate (High)a 11.9 14.1

Planning Estimate (Low)

a 10.1 11.9

Proposed Budget 10.4 12.5

a Excluding OPM

8.9.2.8 W93 Program Cost Estimate

The W93 Program will mitigate future risk to the sea leg of the nuclear triad and address the changing 

strategic environment. DOE/NNSA is coordinating with DoD on specific requirements and design options 

for the W93 Program, which entered Phase 2 in FY 2022. The W93 Program cost estimate (see Table 8–9

and Figure 8–20) is based on preliminary assumptions for one of the W93 designs and provides a planning 

estimate only. The midpoint of the estimates (average of 50 percent and 85 percent) for the entire list of 

options analyzed in the Phase 1 study ranged from $17.1 billion to $26.1 billion in then-year dollars, including 

Other Program Money. These estimates will change as requirements and schedules are refined and will be 

updated in future versions of the SSMP.

Figure 8–20. W93 Modification Program cost from fiscal year 2021 to completion

Table 8–9. Total estimated cost for W93 Program

FY 2021–FY 2047

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Planning Estimate (High) a 17.5 24.8

Planning Estimate (Low) a 14.9 20.9

Proposed Budget 16.2 22.9

a

Including Other Program Money
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8.9.2.9 Future Strategic Missile Warhead Cost Estimates

DOE/NNSA is coordinating with DoD to define the appropriate ballistic missile warheads to support 

anticipated future threats. These warheads currently include the Future Strategic Land-Based Warhead,

the Future Strategic Sea-Based Warhead, the Future Air-Delivered Warhead, and a Submarine-Launched 

Warhead (to replace the W76-1/2) that will be needed in the 2040s. The military capabilities required 

from the Future Strategic Land-Based Warhead and the Future Strategic Sea-Based Warhead, formerly 

referred to as Interoperable Warheads or Future Ballistic Missile Warheads, are being analyzed, and 

appropriate requirements are being developed to address emerging threats. 

The Future Strategic Missile Warhead cost estimates (see Table 8–10, Table 8–11, Table 8–12, and 

Table 8-13) provide a planning estimate for notional systems. These estimates are based on an existing 

stockpile weapon with increased uncertainty in design scope and quantities, adjusted for out-year 

escalation and are informed by the W93 planning estimate. The planned timelines for these future 

warheads are also under consideration and have shifted later than shown in previous SSMPs. These 

estimates will change as requirements and schedules are refined and will be updated in future versions 

of the SSMP.

Table 8–10. Total estimated cost for Future Strategic Missile – Land-Based Warhead

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Planning Estimate (High) a 17.6 36.0

Planning Estimate (Low) a 14.1 28.9

Proposed Budget 15.9 32.4

a

Including Other Program Money

Table 8–11. Total estimated cost for Future Strategic Missile – Sea-Based Warhead

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Planning Estimate (High) a 24.2 41.6

Planning Estimate (Low) a 19.0 32.7

Proposed Budget 21.6 37.1

a

Including Other Program Money

Table 8–12. Total estimated cost for Future Air-Delivered Weapon

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Planning Estimate (High) a 21.8 53.6

Planning Estimate (Low) a 16.7 40.9

Proposed Budget 19.3 47.3

a

Including Other Program Money

Table 8–13. Total estimated cost for Future W76-1/2 Replacement

Dollars in Billions FY 2023 Dollars Then-Year Dollars

Planning Estimate (High) a 26.5 62.4

Planning Estimate (Low) a 20.3 47.8

Proposed Budget 23.4 55.1

a

Including Other Program Money
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8.9.2.10 Summary of Cost Estimates

Figure 8–21 represents the aggregation of cost estimate ranges for all presently known warhead 

modernization programs from FY 2023 through FY 2048 based on schedule assumptions that are subject 

to change. The differences in the values from the FY 2023 SSMP reflect refined estimates for W80-4 and 

W87-1 as well as increases in new estimates from the W93, and also the estimates for other future 

systems. Changes to proposed schedules for the Future Strategic Missile Warheads, whose estimates use 

an escalation of 2.9 percent15, caused the funding profile to shift right by several years from last year’s 

plan. 

Figure 8–21. Total projected Stockpile Major Modernization costs for 

fiscal years 2022–2047 with high and low estimates (then-year dollars)

15 Per NAP 413.6, Confidence Levels and Escalation for Cost Estimating.
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8.9.3 Construction

8.9.3.1 Cost Estimation for Capital Acquisitions

In FY 2020, DOE/NNSA began publishing cost estimates for early-stage capital acquisitions. These early 

planning estimates, published as much as a decade or more before a project’s initial mission approval, 

primarily inform long-term cost projections for programmatic construction and are supplemental to DOE 

acquisition requirements outlined in DOE Order 413.3B. 

Notably, these cost estimates are: 

◼ Performed by an organization separate from the Federal program office16

◼ Performed using a top-down parametric method consistent with early-stage planning

◼ Based on historic DOE/NNSA project schedules, costs, and project phasing

◼ Based on current anticipated project scopes

◼ Based on affordability analysis

◼ Updated annually for the SSMP

Once a project begins the acquisition process, the approved cost estimate ranges at the CD-0 milestone, 

Approve Mission Need, supersede previous estimates and becomes the basis for resource planning. The 

project then progresses as described in DOE Order 413.3B (i.e., alternative selection and cost range at 

CD-1, performance baseline at CD-2, etc.). Per DOE Order 413.3B and DOE/NNSA policy, the project cost 

estimates are reconciled with independent cost estimates or independent cost reviews performed by 

either the Office of Cost Estimating and Program Evaluation (pre-CD-0 and -1) or DOE’s Office of Project 

Management (pre-CD-2).

The early-stage planning estimates use technical input based on an assumed scope. However, these 

assumptions do not predetermine the project’s actual acquisition strategy or the outcome of subsequent 

analysis of alternatives. The assumed scope should be considered estimated until the design matures and 

the project reaches CD-2, Performance Baseline.

The cost estimation professional society, American Association of Cost Engineering International, has 

published a cost estimate classification system17 based on the scope definition of the project. DOE/NNSA

has mapped the American Association of Cost Engineering International cost estimate classes to the most 

common uses for capital acquisitions.

18 Table 8–13 summarizes the cost estimation classification system, 

including the level of project definition, the expected uncertainty range, and the corresponding 

DOE/NNSA capital acquisition milestones. Note that the estimate ranges and typical applications 

represent rough expectations and cannot simply be applied to an estimate to determine uncertainty.

16 The DOE/NNSA OMB Office of Programing, Analysis, and Evaluation performs the cost estimates on behalf of Defense Programs.

17 American Association of Cost Engineering International Recommended Practice 18R-97, Cost Estimation Classification System 

as Applied in Engineering, Procurement and Construction for the Process Industries.

18 DOE Guide 413.3-21A, Cost Estimating Guide.
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Table 8–13. Capital Acquisition Cost Estimate Classification System 

Estimate 

Class

Primary 

Characteristic Secondary Characteristic

Maturity Level 

of Project 

Definition

(percent)

DOE Capital Acquisition 

Milestone

Typical Types of 

Estimate Methodology

Expected Accuracy 

Range (percent)

Class 5 0 to 2 Mission Need (CD-0) Planning Estimate, 

Rough Order of 

Magnitude

Capacity factored, 

parametric models, 

judgment, or analogy

Low: -20 to -50

High: +30 to +100

Class 4 1 to 15 Alternative Selection (CD-1) Analysis of Alternatives, 

Conceptual Design

Equipment factored 

or parametric models

Low: -15 to -30

High: +20 to +50

Class 3 10 to 40 Performance Baseline (CD-2)

(low-risk projects)

Preliminary Design Semi-detailed unit 

costs with assembly 

level line-items

Low: -10 to -20

High: +10 to +30

Class 2 30 to 75 Start of Construction (CD-3)/ 

Performance Baseline (CD-2)

(high-risk projects)

Final Design Detailed unit cost 

with forced detailed 

take-off

Low: -5 to -15

High: +5 to +20

Class 1 65 to 100 Detailed unit cost 

with detailed take-off

Low: -3 to -10

High: +3 to +15

CD = Critical Decision

8.9.3.2 Fiscal Year 2024 through Fiscal Year 2048 Estimates

The budget request for capital acquisitions in FY 2024 reflects the latest estimates for existing 

construction projects. DOE/NNSA continues to execute the schedules of multiple ongoing major capital 

acquisition projects. A list of major capital acquisition project proposals has been developed through the 

efforts of a series of working groups and deep dives with representatives from DOE/NNSA sites and 

responsible Federal offices. Both project- and portfolio-level planning initiatives are in progress to ensure 

DOE/NNSA is consistently funding the highest-priority infrastructure investments across the enterprise. 

The schedule for the current 25-year plan of major capital acquisition projects and project proposals is 

listed in Chapter 6, “Infrastructure and Operations.” This planning schedule will be updated annually

based on available funding and programmatic priorities.

8.10 Affordability

The FY 2024 President’s Budget Request fully supports DOE/NNSA’s needs. As described throughout this 

document, DOE/NNSA is undertaking a risk-informed, complex, and time-constrained modernization and 

recapitalization effort in coordination with DoD. DOE/NNSA is making concerted investments in its 

production facilities so that the necessary capabilities and infrastructure will be available to execute 

modernization programs to meet DoD timelines. Additionally, DOE/NNSA is working to maintain and 

upgrade its science and technology infrastructure so that it can continue supporting the cutting-edge science 

that underpins science-based stockpile stewardship and enables continued confidence in the reliability of 

the nuclear stockpile without the need for underground testing.
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Figure 8–22 depicts updated Weapons Activities budget projections beyond the FYNSP, based on the 

FY 2024 President’s Budget Request and a continuation of the program of record. The budget projection 

incorporates the Stockpile Major Modernization program cost estimates described in Section 8.9.2 and the 

cost estimates for the planned major programmatic construction projects described in Chapter 6, 

Section 6.2.1; these estimates are augmented by as-yet-unplanned construction beginning after FY 2040. 

Significant out-year estimates included in Figure 8–22 are:

◼ Reestablishing a plutonium pit production capability 

◼ Reestablishing a domestic uranium enrichment capability

◼ Revitalizing depleted uranium manufacturing capability

◼ Establishing and modernizing DOE/NNSA’s SRT&E capabilities for certifying warheads upon entry 

into the stockpile

The FY 2024 budget assumes a National Defense topline, including the DOE/NNSA topline, for FY 2029 

through FY 2033 that grows at 0.7 percent. However, for illustrative purposes of this affordability analysis 

and to conform to assumptions in prior versions of the SSMP, DOE/NNSA assumes that funding for FY 2029 

through FY 2050 will be escalated at 2.1 percent. This projection does not and cannot include unknown 

requirements, which may necessitate additional Stockpile Major Modernization programs, enhanced 

Stockpile Sustainment activities, R&D efforts, or further infrastructure investments. Out-year projections 

are adjusted annually as part of the programming process to align the total resource needs with available 

resources. As projected available resources are made clearer for years outside of the FYSNP, current 

capability and mission needs are examined and prioritized to build a program that maximizes the safety, 

security and effectiveness of the nuclear deterrent while staying within the available resources. If there are 

significant changes to future requirements, DOE/NNSA, in conjunction with DoD, would be forced to make 

difficult decisions with respect to scope and schedule of projects, or defer construction or recapitalization 

projects. Limiting risk across the nuclear security enterprise is a key consideration.
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Figure 8–22. Projected out-year budget estimates for DOE/NNSA Weapons Activities

in then-year dollars
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Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page 9-1

Chapter 9

Conclusion

This Department of Energy’s National Nuclear Security Administration (DOE/NNSA) Fiscal Year 2024

Stockpile Stewardship and Management Plan (FY 2024 SSMP), together with its classified annex, is a key 

planning document for the nuclear security enterprise. This FY 2024 SSMP is the culmination of planning 

efforts across numerous DOE/NNSA programs and organizations and documents the 25-year plan for 

ensuring the safety, security, and effectiveness of the U.S. nuclear stockpile. The FY 2024 SSMP also 

details efforts to maintain the scientific and engineering tools, capabilities, and infrastructure that 

underpin the current and future nuclear deterrent. The SSMP was prepared by the DOE/NNSA Federal 

workforce in collaboration with DOE/NNSA’s management and operating partners and coordinated with 

the Department of Defense (DoD) through the Nuclear Weapons Council. 

The global threat environment continues to rapidly evolve and grow increasingly dangerous, complex, and 

uncertain. In response to this changing environment, the United States must develop a modern, resilient, 

and flexible nuclear security enterprise to provide DoD with the necessary capabilities to continue to 

execute its critical nuclear deterrent mission. Together with support from Congress, DOE/NNSA will 

provide the nuclear security enterprise workforce with the resources and responsive, agile infrastructure 

needed to steward the systems that comprise the deterrent today, while preparing for the cutting-edge 

research and development that will inform the national security mission solutions of tomorrow. 
Department of Energy/National Nuclear Security Administration | November 2023

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Appendix A

Requirements Mapping

A.1 National Nuclear Security Administration Response to 

Statutory Reporting Requirements and Related Requests

The Fiscal Year 2024 Stockpile Stewardship and Management Plan (FY 2024 SSMP) consolidates a number 

of statutory reporting requirements and related congressional requests. This appendix maps the statutory 

and congressional requirements to the respective chapter and section in the FY 2024 SSMP. 

A.2 50 U.S. Code § 2523

50 U.S. Code § 2523 FY 2023 Response FY 2024 Response

§ 2523. Nuclear weapons stockpile stewardship, management, and responsiveness

plan

(a) Plan requirement

The Administrator, in consultation with the Secretary of Defense and other 

appropriate officials of the departments and agencies of the Federal Government, 

shall develop and annually update a plan for sustaining the nuclear weapons 

stockpile. The plan shall cover, at a minimum, stockpile stewardship, stockpile 

management, stockpile responsiveness, stockpile surveillance, program direction, 

infrastructure modernization, human capital, and nuclear test readiness. The plan 

shall be consistent with the programmatic and technical requirements of the most 

recent annual Nuclear Weapons Stockpile Memorandum.

Unclassified

Message from the 

NNSA Administrator;

Message from the 

Secretary; 

Chapters 2, 4, 6, 7;

Appendix D

Classified Annex

(b) Submissions to Congress

(1) In accordance with subsection (c), not later than March 15 of each evennumbered year, the Administrator shall submit to the congressional defense 

committees a summary of the plan developed under subsection (a). 

Unclassified

Message from the 

NNSA 

Administrator; 

All Chapters

N/A

(2) In accordance with subsection (d), not later than March 15 of each oddnumbered year, the Administrator shall submit to the congressional defense 

committees a detailed report on the plan developed under subsection (a). 

N/A Unclassified

All Chapters

(3) The summaries and reports required by this subsection shall be submitted 

in unclassified form, but may include a classified annex.

(c) Elements of biennial plan summary

Each summary of the plan submitted under subsection (b)(1) shall include, at a 

minimum, the following:

(1) A summary of the status of the nuclear weapons stockpile, including the 

number and age of warheads (including both active and inactive) for each 

warhead type.

Unclassified

Chapter 1,

Section 1.3, 

Figure 1-1

N/A
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(2) A summary of the status, plans, budgets, and schedules for warhead life 

extension programs and any other programs to modify, update, or replace 

warhead types.

Unclassified

Chapter 1,

Section 1.4;

Chapter 2,

Section 2.2,

Figure 2-2

N/A

(3) A summary of the methods and information used to determine that the 

nuclear weapons stockpile is safe and reliable, as well as the relationship of 

science-based tools to the collection and interpretation of such information.

Unclassified

Chapter 2, 

Sections 2.1, 2.2

N/A

(4) A summary of the status of the nuclear security enterprise, including 

programs and plans for infrastructure modernization and retention of human 

capital, as well as associated budgets and schedules.

Unclassified

Chapter 4, 

Sections 4.2, 4.3; 

Appendix C, 

Section C-1

N/A

(5) A summary of the status, plans, and budgets for carrying out the stockpile 

responsiveness program under section 2538b of this title.

Unclassified

Chapter 2, 

Section 2.1; 

Chapter 5, 

Section 5.4

N/A

(6) A summary of the plan regarding the research and development, 

deployment, and lifecycle sustainment of technologies described in subsection 

(d) (7).

Unclassified

Chapter 1, 

Sections 1.4, 1.5, 

Figure 1-3

N/A

(7) A summary of the assessment under subsection (d)(8) regarding the 

execution of programs with current and projected budgets and any associated 

risks.

Unclassified

Chapter 5, 

Sections 5.1, 5.5, 

5.6, 5.9

N/A

(8) Identification of any modifications or updates to the plan since the 

previous summary or detailed report was submitted under subsection (b).

Unclassified

Chapter 5, 

Section 5.4

N/A

(9) Such other information as the Administrator considers appropriate.

(d) Elements of biennial detailed report

Each detailed report on the plan submitted under subsection (b)(2) shall include, 

at a minimum, the following:

(1) With respect to stockpile stewardship, stockpile management, and 

stockpile responsiveness—

(A) the status of the nuclear weapons stockpile, including the number and 

age of warheads (including both active and inactive) for each warhead 

type;

N/A Unclassified

Chapter 1, 

Section 1.3, 

Table 1-1

Classified Annex

(B) for each five-year period occurring during the period beginning on the 

date of the report and ending on the date that is 20 years after the date of 

the report—

(i) the planned number of nuclear warheads (including active and 

inactive) for each warhead type in the nuclear weapons stockpile; and

(ii) the past and projected future total lifecycle cost of each type of 

nuclear weapon;

N/A Unclassified

Chapter 2, 

Section 2.2, 

Figure 2-2; 

Chapter 8, 

Sections 8.9, 8.9.2.2, 

8.9.2.3, Table 8-4

Classified Annex
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(C) the status, plans, budgets, and schedules for warhead life extension 

programs and any other programs to modify, update, or replace warhead 

types;

N/A Unclassified

Chapter 2, 

Sections 2.2; 

Chapter 8, 

Section 8.9.2, 

Figures 8-16–8-22, 

Tables 8-5–8-13

Classified Annex

(D) a description of the process by which the Administrator assesses the 

lifetimes, and requirements for life extension or replacement, of the 

nuclear and non-nuclear components of the warheads (including active and 

inactive warheads) in the nuclear weapons stockpile;

N/A Unclassified

Chapter 2, 

Sections 2.1, 2.2, 

2.3; Chapter 4, 

Sections 4.2.2, 4.3.2

Classified Annex

(E) a description of the process used in recertifying the safety, security, and 

reliability of each warhead type in the nuclear weapons stockpile;

N/A Unclassified

Chapter 2, 

Sections 2.1.1, 

2.1.1.1–2.1.1.2; 

Chapter 4, 

Section 4.2.1, 

Figure 4-2

Classified Annex

(F) any concerns of the Administrator that would affect the ability of the 

Administrator to recertify the safety, security, or reliability of warheads in 

the nuclear weapons stockpile (including active and inactive warheads);

N/A Unclassified

Chapter 1, Overview; 

Chapter 6, 

Section 6.1

Classified Annex

(G) mechanisms to provide for the manufacture, maintenance, and 

modernization of each warhead type in the nuclear weapons stockpile, as 

needed;

N/A Unclassified

Chapter 3, 

Sections 3.1–3.4; 

Chapter 4, 

Sections 4.2.1, 4.2.4, 

Figure 4-2

(H) mechanisms to expedite the collection of information necessary for 

carrying out the stockpile management program required by section 2524 

of this title, including information relating to the aging of materials and 

components, new manufacturing techniques, and the replacement or 

substitution of materials;

N/A Unclassified

Chapter 4, 

Sections 4.2.4, 4.3

(I) mechanisms to ensure the appropriate assignment of roles and missions 

for each national security laboratory and nuclear weapons production 

facility, including mechanisms for allocation of workload, mechanisms to 

ensure the carrying out of appropriate modernization activities, and 

mechanisms to ensure the retention of skilled personnel;

N/A Unclassified

Chapter 1, 

Section 1.2; 

Chapter 7, 

Sections 7.3.3, 7.4; 

Appendix F

(J) mechanisms to ensure that each national security laboratory has full 

and complete access to all weapons data to enable a rigorous peer-review 

process to support the annual assessment of the condition of the nuclear 

weapons stockpile required under section 2525 of this title;

N/A Unclassified

Chapter 1, 

Section 1.2.1; 

Classified Annex

(K) mechanisms for allocating funds for activities under the stockpile 

management program required by section 2524 of this title, including 

allocations of funds by weapon type and facility; and

N/A Unclassified

Chapter 8, 

Sections 8.9.2.2, 

8.9.2.3, Table 8-4

(L) for each of the five fiscal years following the fiscal year in which the 

report is submitted, an identification of the funds needed to carry out the 

program required under section 2524 of this title;

N/A Unclassified

Chapter 8, 

Section 8.3, 

Table 8-1
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(M) the status, plans, activities, budgets, and schedules for carrying out the 

stockpile responsiveness program under section 2538b of this title; 

N/A Unclassified

Appendix D

(N) for each of the five fiscal years following the fiscal year in which the 

report is submitted, an identification of the funds needed to carry out the 

program required under section 2538b of this title; and

N/A Unclassified

Chapter 8, 

Section 8.3, 

Table 8-1

(O) as required, when assessing and developing prototype nuclear 

weapons of foreign countries, a report from the directors of the national 

security laboratories on the need and plan for such assessment and 

development that includes separate comments on the plan from the 

Secretary of Energy and the Director of National Intelligence.

N/A N/A

(2) With respect to science-based tools—

(A) a description of the information needed to determine that the nuclear 

weapons stockpile is safe and reliable;

N/A Unclassified

Chapter 2, 

Sections 2.1.1, 

2.1.1.1–2.1.1.2; 

Chapter 4, 

Sections 4.2.1, 4.3.1

Classified Annex

(B) for each science-based tool used to collect information described in 

subparagraph (A), the relationship between such tool and such information 

and the effectiveness of such tool in providing such information based on 

the criteria developed pursuant to section 2522(a) of this title; and

N/A Unclassified

Chapter 2, 

Section 2.2; 

Chapter 4, 

Section 4.3

(C) the criteria developed under section 2522(a) of this title (including any 

updates to such criteria).

N/A Classified Annex

(3) An assessment of the stockpile stewardship program under section 2521 

(a) of this title by the Administrator, in consultation with the directors of the 

national security laboratories, which shall set forth—

(A) an identification and description of—

(i) any key technical challenges to the stockpile stewardship program; 

and

(ii) the strategies to address such challenges without the use of nuclear 

testing;

N/A Unclassified

Chapter 4, 

Sections 4.3.1–4.3.4, 

Tables 4-1–4-4

Classified Annex

(B) a strategy for using the science-based tools (including advanced 

simulation and computing capabilities) of each national security laboratory 

to ensure that the nuclear weapons stockpile is safe, secure, and reliable 

without the use of nuclear testing;

N/A Unclassified

Chapter 4, 

Sections 4.3.4, 

Table 4-4

(C) an assessment of the science-based tools (including advanced 

simulation and computing capabilities) of each national security laboratory 

that exist at the time of the assessment compared with the science-based 

tools expected to exist during the period covered by the future-years 

nuclear security program; and

N/A Unclassified

Chapter 4, 

Sections 4.2, 4.3, 

Table 4-4

(D) an assessment of the core scientific and technical competencies 

required to achieve the objectives of the stockpile stewardship program 

and other weapons activities and weapons-related activities of the 

Administration, including—

N/A Unclassified

Chapter 4, 

Section 4.3, 4.3.1–

4.3.5, Figure 4-3, 

Tables 4-1–4-4

(i) the number of scientists, engineers, and technicians, by discipline, 

required to maintain such competencies; and

N/A Unclassified

Chapter 7, 

Section 7.1.2, 

Figure 7-2
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(ii) a description of any shortage of such individuals that exists at the 

time of the assessment compared with any shortage expected to exist 

during the period covered by the future-years nuclear security 

program.

N/A Unclassified

Chapter 7, 

Section 7.4, 

Table 7-1

(4) With respect to the nuclear security infrastructure—

(A) a description of the modernization and refurbishment measures the 

Administrator determines necessary to meet the requirements prescribed 

in—

N/A

(i) the national security strategy of the United States as set forth in the 

most recent national security strategy report of the President under 

section 3043 of this title if such strategy has been submitted as of the 

date of the plan; 

N/A Unclassified

Executive Summary; 

Chapter 6

(ii) the most recent quadrennial defense review if such strategy has 

not been submitted as of the date of the plan; and

N/A Unclassified

Executive Summary; 

Chapter 6

(iii) the most recent Nuclear Posture Review as of the date of the plan; N/A Unclassified

Executive Summary; 

Chapter 6

(B) a schedule for implementing the measures described under 

subparagraph (A) during the 10-year period following the date of the plan; 

N/A Unclassified

Chapter 6, 

Section 6.3.1, 6.3.2

(C) the estimated levels of annual funds the Administrator determines 

necessary to carry out the measures described under subparagraph (A), 

including a discussion of the criteria, evidence, and strategies on which 

such estimated levels of annual funds are based; and

N/A Unclassified

Chapter 8, 

Sections 8.7, 8.9.3, 

Figure 8-12, 

Table 8-13

(D) a description of—

(I) the metrics (based on industry best practices) used by the 

Administrator to determine the infrastructure deferred maintenance 

and repair needs of the nuclear security enterprise; and 

(II) the percentage of replacement plant value being spent on 

maintenance and repair needs of the nuclear security enterprise; and

(III) an explanation of whether the annual spending on such needs 

complies with the recommendation of the National Research Council of 

the National Academies of Sciences, Engineering, and Medicine that 

such spending be in an amount equal to four percent of the replacement 

plant value, and, if not, the reasons for such noncompliance and a plan 

for how the Administrator will ensure facilities of the nuclear security 

enterprise are being properly sustained.

N/A Unclassified

Chapter 8, 

Section 8.7, 

Table 8-2

(5) With respect to the nuclear test readiness of the United States—

(A) an estimate of the period of time that would be necessary for the 

Administrator to conduct an underground test of a nuclear weapon once 

directed by the President to conduct such a test;

N/A Unclassified

Chapter 4, 

Section 4.4

(B) a description of the level of test readiness that the Administrator, in 

consultation with the Secretary of Defense, determines to be appropriate;

N/A Unclassified

Chapter 4, 

Section 4.4

(C) a list and description of the workforce skills and capabilities that are 

essential to carrying out an underground nuclear test at the Nevada 

National Security Site;

N/A Unclassified

Chapter 4, 

Section 4.4; 

Appendix F, 

Section F.4.1.5
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(D) a list and description of the infrastructure and physical plants that are 

essential to carrying out an underground nuclear test at the Nevada 

National Security Site; and

N/A Unclassified

Chapter 4, 

Section 4.4; 

Appendix F,

Section F.4.1.3

(E) an assessment of the readiness status of the skills and capabilities 

described in subparagraph (C) and the infrastructure and physical plants 

described in subparagraph (D).

N/A Unclassified

Chapter 4, 

Section 4.4; 

Appendix F, 

Sections F.4.1.3, 

F.4.1.5

(6) A strategy for the integrated management of plutonium for stockpile and 

stockpile stewardship needs over a 20-year period that includes the following:

(A) An assessment of the baseline science issues necessary to understand 

plutonium aging under static and dynamic conditions under manufactured 

and nonmanufactured plutonium geometries.

N/A Unclassified

Chapter 4, 

Sections 4.3.1, 4.3.2

(B) An assessment of scientific and testing instrumentation for plutonium 

at elemental and bulk conditions.

N/A Unclassified

Chapter 4, 

Sections 4.3.1, 4.3.2

(C) An assessment of manufacturing and handling technology for 

plutonium and plutonium components.

N/A Unclassified

Chapter 4, 

Sections 4.3.1, 4.3.2

(D) An assessment of computational models of plutonium performance 

under static and dynamic loading, including manufactured and 

nonmanufactured conditions.

N/A Unclassified

Chapter 4, 

Section 4.3.4

(E) An identification of any capability gaps with respect to the assessments 

described in subparagraphs (A) through (D).

N/A Unclassified

Chapter 4, 

Sections 4.3.1–4.3.4

(F) An estimate of costs relating to the issues, instrumentation, technology, 

and models described in subparagraphs (A) through (D) over the period 

covered by the future-years nuclear security program under section 2453 

of this title.

N/A Unclassified

Chapter 8, 

Section 8.6.1, 

Figure 8-8

(G) An estimate of the cost of eliminating the capability gaps identified 

under subparagraph (E) over the period covered by the future-years 

nuclear security program.

N/A Unclassified

Chapter 8, 

Section 8.3, 

Table 8-1

(H) Such other items as the Administrator considers important for the 

integrated management of plutonium for stockpile and stockpile 

stewardship needs.

N/A Unclassified

Chapter 3, 

Section 3.1.1

7) A plan for the research and development, deployment, and lifecycle 

sustainment of the technologies employed within the nuclear security 

enterprise to address physical and cyber security threats during the five fiscal 

years following the date of the report, together with—

N/A Unclassified

Chapter 5, 

Sections 5.2, 5.3

Classified Annex

(A) for each site in the nuclear security enterprise, a description of the 

technologies deployed to address the physical and cybersecurity threats 

posed to that site; 

N/A Unclassified

Chapter 5, 

Section 5.3.2

Classified Annex

(B) for each site and for the nuclear security enterprise, the methods used 

by the Administration to establish priorities among investments in physical 

and cybersecurity technologies; and 

N/A Unclassified

Chapter 8, 

Sections 8.8.4, 8.8.5

Classified Annex

(C) a detailed description of how the funds identified for each program 

element specified pursuant to paragraph (1) in the budget for the 

Administration for each fiscal year during that five-fiscal-year period will 

help carry out that plan.

N/A Unclassified

Chapter 8
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(8) An assessment of whether the programs described by the report can be 

executed with current and projected budgets and any associated risks.

N/A Unclassified

Chapter 8, 

Sections 8.9, 8.10

(9) Identification of any modifications or updates to the plan since the 

previous summary or detailed report was submitted under subsection (b).

N/A Unclassified

Chapter 8

(e) Nuclear Weapons Council assessment 

(1) For each detailed report on the plan submitted under subsection (b)(2), the 

Nuclear Weapons Council shall conduct an assessment that includes the 

following:

(A) An analysis of the plan, including—

(i) whether the plan supports the requirements of the national security 

strategy of the United States or the most recent quadrennial defense 

review, as applicable under subsection (d)(4)(A), and the Nuclear 

Posture Review;

(ii) whether the modernization and refurbishment measures described 

under subparagraph (A) of subsection (d)(4) and the schedule 

described under subparagraph (B) of such subsection are adequate to 

support such requirements; and

(iii) whether the plan supports the stockpile responsiveness program 

under section 2538b of this title in a manner that meets the objectives 

of such program and an identification of any improvements that may 

be made to the plan to better carry out such program.

(B) An analysis of whether the plan adequately addresses the requirements 

for infrastructure recapitalization of the facilities of the nuclear security 

enterprise.

(C) If the Nuclear Weapons Council determines that the plan does not 

adequately support modernization and refurbishment requirements under 

subparagraph (A) or the nuclear security enterprise facilities infrastructure 

recapitalization requirements under subparagraph (B), a risk assessment 

with respect to—

(i) supporting the annual certification of the nuclear weapons stockpile; 

and

(ii) maintaining the long-term safety, security, and reliability of the 

nuclear weapons stockpile.

(2) Not later than 180 days after the date on which the Administrator submits 

the plan under subsection (b)(2), the Nuclear Weapons Council shall submit to 

the congressional defense committees a report detailing the assessment 

required under paragraph (1).

N/A N/A
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50 U.S. Code § 2523 FY 2023 Response FY 2024 Response

(f) Definitions – In this section:

(1) The term “budget”, with respect to a fiscal year, means the budget for 

that fiscal year that is submitted to Congress by the President under section 

1105(a) of title 31.

(2) The term “future-years nuclear security program” means the program 

required by section 2453 of this title.

(3) The term “nuclear security budget materials”, with respect to a fiscal year, 

means the materials submitted to Congress by the Administrator in support 

of the budget for that fiscal year.

(4) The term “quadrennial defense review” means the review of the defense 

programs and policies of the United States that is carried out every four years 

under section 118 of title 10.

(5) The term “weapons activities” means each activity within the budget 

category of weapons activities in the budget of the Administration.

(6) The term “weapons-related activities” means each activity under the 

Department of Energy that involves nuclear weapons, nuclear weapons 

technology, or fissile or radioactive materials, including activities related to—

(A) nuclear nonproliferation;

(B) nuclear forensics;

(C) nuclear intelligence;

(D) nuclear safety; and

(E) nuclear incident response.

Unclassified

Appendix G

Unclassified

Appendix G

A.3 50 U.S. Code § 2538a

50 U.S. Code § 2538a 

FY 2023

Response

FY 2024

Response

§2538a. Plutonium pit production capacity Unclassified Unclassified

(a) Requirement 

Consistent with the requirements of the Secretary of Defense, the Secretary 

of Energy shall ensure that the nuclear security enterprise-

(1) during 2021, begins production of qualification plutonium pits;

(2) during 2024, produces not less than 10 war reserve plutonium pits;

(3) during 2025, produces not less than 20 war reserve plutonium pits;

(4) during 2026, produces not less than 30 war reserve plutonium pits; and

(5) during 2030, produces not less than 80 war reserve plutonium pits.

Executive 

Summary; 

Chapter 3, 

Section 3.4.1; 

Chapter 4, 

Section 4.2.1; 

Chapter 5, 

Section 5.5.3

Executive 

Summary; 

Chapter 3, 

Sections 3.3.1, 

3.1.1.2, 

Table 3-1; 

Chapter 6, 

Section 6.3.1.4

(b) Annual certification

Not later than March 1, 2015, and each year thereafter through 2030, the 

Secretary of Energy shall certify to the congressional defense committees and the 

Secretary of Defense that the programs and budget of the Secretary of Energy will 

enable the nuclear security enterprise to meet the requirements under 

subsection (a).

Unclassified

Chapter 3, 

Section 3.4.1; 

Chapter 5, 

Sections 5.5.3, 5.9.2

N/A

(c) Plan

If the Secretary of Energy does not make a certification under subsection (b) by 

March 1 of any year in which a certification is required under that subsection, by 

not later than May 1 of such year, the Chairman of the Nuclear Weapons Council 

shall submit to the congressional defense committees a plan to enable the nuclear 

security enterprise to meet the requirements under subsection (a). Such plan shall 

include identification of the resources of the Department of Energy that the 

Chairman determines should be redirected to support the plan to meet such 

requirements.

N/A N/A
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A.4 H.R. 116-449 

H.R. 116-449 – ENERGY AND WATER DEVELOPMENT AND RELATED

AGENCIES APPROPRIATIONS BILL, 2021, July 15, 2020, pp 141-142

FY 2023

Response

FY 2024

Response1

Stockpile Responsiveness Program Unclassified

Appendix E

Unclassified

Appendix D The NNSA shall submit to the Committee an annual report with the budget request 

that includes a detailed accounting and status of each program, project, and activity 

within the program. The Committee expects to receive timely updates on the status of 

any new and existing taskings, studies, and assessments.

A.5 H.R. 244

H.R.244 – Consolidated Appropriations Act, 2017, P.L. 115-31

FY 2023

Response

FY 2024

Response

SEC. 4. EXPLANATORY STATEMENT.

The explanatory statement regarding this Act, printed in the House section of the 

Congressional Record on or about May 2, 2017, and submitted by the Chairman of the 

Committee on Appropriations of the House, shall have the same effect with respect to 

the allocation of funds and implementation of divisions A through L of this Act as if it 

were a joint explanatory statement of a committee of conference.

Congressional Record – House, Vol 163, No 76—Book II, page H3753, May 3, 2017

(Explanatory Statement to Accompany the FY 17 Omnibus Appropriations

[P.L. 115-31]]

Life Extension Reporting. – The NNSA is directed to provide to the Committees on 

Appropriations of both Houses of Congress a classified summary of each ongoing life 

extension and major refurbishment program that includes explanatory information on 

the progress and planning for each program beginning with the award of the phase 6.3 

milestone and annually thereafter until completion of the program.

Classified Annex Classified Annex

A.6 Related Legislation: 50 U.S. Code § 2521

50 U.S. Code § 2521

§ 2521. Stockpile stewardship program

(a) Establishment

The Secretary of Energy, acting through the Administrator for Nuclear Security, shall establish a stewardship program to 

ensure –

(1) the preservation of the core intellectual and technical competencies of the United States in nuclear weapons, 

including weapons design, system integration, manufacturing, security, use control, reliability assessment, and 

certification; and 

(2) that the nuclear weapons stockpile is safe, secure, and reliable without the use of underground nuclear weapons 

testing.

1 H. Rept. 117-98 accompanying the Energy and Water Development and Related Agencies Appropriations Bill, 2022 restated this 

annual Stockpile Responsiveness Program reporting requirement and noted that as the Stockpile Stewardship and Management 

Plan (SSMP) does not typically accompany the annual budget request, including the report within the SSMP, “therefore does not 

offer a useful and timely companion to the budget.” This direction was reiterated again through Joint Explanatory Statement 

accompanying the Energy and Water Development and Related Agencies Appropriations Act, 2022. In accordance with this 

direction, Department of Energy’s National Nuclear Security Administration (DOE/NNSA) submitted the report as a standalone 

document to provide as timely updates as possible and resubmitted within the SSMP, as the SSMP is also required to provide 

information on the Stockpile Responsiveness Program under 50 USC 2523 and 2523(c)(5), as noted.
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50 U.S. Code § 2521

(b) Program elements

The program shall include the following:

1) An increased level of effort for advanced computational capabilities to enhance the simulation and modeling 

capabilities of the United States with respect to the performance over time of nuclear weapons.

(2) An increased level of effort for above-ground experimental programs, such as hydrotesting, high-energy lasers, 

inertial confinement fusion, plasma physics, and materials research.

(3) Support for new facilities construction projects that contribute to the experimental capabilities of the United 

States, such as an advanced hydrodynamics facility, the National Ignition Facility, and other facilities for aboveground experiments to assess nuclear weapons effects.

(4) Support for the use of, and experiments facilitated by, the advanced experimental facilities of the United States, 

including -

(A) the National Ignition Facility at Lawrence Livermore National Laboratory;

(B) the Dual Axis Radiographic Hydrodynamic Testing facility at Los Alamos National Laboratory;

(C) the Z Machine at Sandia National Laboratories; and 

(D) the experimental facilities at the Nevada National Security Site.

(5) Support for the sustainment and modernization of facilities with production and manufacturing capabilities that 

are necessary to ensure the safety, security, and reliability of the nuclear weapons stockpile, including -

(A) the nuclear weapons production facilities; and

(B) production and manufacturing capabilities resident in the national security laboratories.

(1) With respect to exascale computing—

(a) PLAN REQUIRED.—The Administrator for Nuclear Security shall develop and carry out a plan to develop exascale 

computing and incorporate such computing into the stockpile stewardship program under section 4201 of the Atomic 

Energy Defense Act (50 U.S.C. 2521) during the 10-year period beginning on the date of the enactment of this Act [Dec. 

26, 2013]

(b) MILESTONES.—The plan required by subsection (a) shall include major programmatic milestones in—

(1) the development of a prototype exascale computer for the stockpile stewardship program; and

(2) mitigating disruptions resulting from the transition to exascale computing.

(c) COORDINATION WITH OTHER AGENCIES.—In developing the plan required by subsection (a), the Administrator shall 

coordinate, as appropriate, with the Under Secretary of Energy for Science, the Secretary of Defense, and elements of 

the intelligence community (as defined in section 3(4) of the National Security Act of 1947 (50 U.S.C. 3003[4]).

(d) INCLUSION OF COSTS IN FUTURE-YEARS NUCLEAR SECURITY PROGRAM.—The Administrator shall—

(1) address, in the estimated expenditures and proposed appropriations reflected in each future-years nuclear 

security program submitted under section 3253 of the National Nuclear Security Administration Act (50 U.S.C. 2453) 

during the 10-year period beginning on the date of the enactment of this Act, the costs of—

(A) developing exascale computing and incorporating such computing into the stockpile stewardship program; 

and

(B) mitigating potential disruptions resulting from the transition to exascale computing; and

(2) include in each such future-years nuclear security program a description of the costs of efforts to develop 

exascale computing borne by the National Nuclear Security Administration, the Office of Science of the Department 

of Energy, other Federal agencies, and private industry.

(e) SUBMISSION TO CONGRESS.—The Administrator shall submit the plan required by subsection (a) to the congressional 

defense committees [Committees on Armed Services and Appropriations of Senate and the House of Representative] 

with each summary of the plan required by subsection (a) of section 4203 of the Atomic Energy Defense Act 

(50 U.S.C. 2523) submitted under subsection (b)(1) of that section during the 10-year period beginning on the date of the 

enactment of this Act.

(f) EXASCALE COMPUTING DEFINED.—In this section, the term ‘‘exascale computing’’ means computing through the use 

of a computing machine that performs near or above 10 to the 18th power floating point operations per second.
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A.7 Related Legislation: 50 U.S. Code § 2522

50 U.S. Code § 2522

§ 2522. Stockpile stewardship criteria 

(a) Requirement for criteria

The Secretary of Energy shall develop clear and specific criteria for judging whether the science-based tools being used 

by the Department of Energy for determining the safety and reliability of the nuclear weapons stockpile are performing 

in a manner that will provide an adequate degree of certainty that the stockpile is safe and reliable.

(b) Coordination with Secretary of Defense

The Secretary of Energy, in developing the criteria required by subsection (a), shall coordinate with the Secretary of 

Defense. 

A.8 Related Legislation: 50 U.S. Code § 2524

50 U.S. Code § 2524

§ 2524. Stockpile management program

(a) Program required

The Secretary of Energy, acting through the Administrator for Nuclear Security and in consultation with the Secretary of 

Defense, shall carry out a program, in support of the stockpile stewardship program, to provide for the effective 

management of the weapons in the nuclear weapons stockpile, including the extension of the effective life of such 

weapons. The program shall have the following objectives:

(1) To increase the reliability, safety, and security of the nuclear weapons stockpile of the United States.

(2) To further reduce the likelihood of the resumption of underground nuclear weapons testing.

(3) To achieve reductions in the future size of the nuclear weapons stockpile.

(4) To reduce the risk of an accidental detonation of an element of the stockpile.

(5) To reduce the risk of an element of the stockpile being used by a person or entity hostile to the United States, its 

vital interests, or its allies.

(b) Program limitations

In carrying out the stockpile management program under subsection (a), the Secretary of Energy shall ensure that—

(1) any changes made to the stockpile shall be made to achieve the objectives identified in subsection (a); and 

(2) any such changes made to the stockpile shall—

(A) remain consistent with basic design parameters by including, to the maximum extent feasible, components 

that are well understood or are certifiable without the need to resume underground nuclear weapons testing; 

and

(B) use the design, certification, and production expertise resident in the nuclear security enterprise to fulfill 

current mission requirements of the existing stockpile.

(c) Program budget

In accordance with the requirements under section 2529 of this title, for each budget submitted by the President to 

Congress under section 1105 of title 31, the amounts requested for the program under this section shall be clearly 

identified in the budget justification materials submitted to Congress in support of that budget.
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A.9 Related Legislation: 50 U.S. Code § 2538b

50 U.S. Code § 2538b

§ 2538b. Stockpile responsiveness program

(a) Statement of policy

It is the policy of the United States to identify, sustain, enhance, integrate, and continually exercise all capabilities 

required to conceptualize, study, design, develop, engineer, certify, produce, and deploy nuclear weapons to ensure the 

nuclear deterrent of the United States remains safe, secure, reliable, credible, and responsive.

(b) Program required

The Secretary of Energy, acting through the Administrator and in consultation with the Secretary of Defense, shall carry 

out a stockpile responsiveness program, along with the stockpile stewardship program under section 2521 of this title and 

the stockpile management program under section 2524 of this title, to identify, sustain, enhance, integrate, and 

continually exercise all capabilities required to conceptualize, study, design, develop, engineer, certify, produce, and 

deploy nuclear weapons.

(c) Objectives The program under subsection (b) shall have the following objectives:

(1) Identify, sustain, enhance, integrate, and continually exercise all of the capabilities, infrastructure, tools, and 

technologies across the science, engineering, design, certification, and manufacturing cycle required to carry out all 

phases of the joint nuclear weapons life cycle process, with respect to both the nuclear security enterprise and 

relevant elements of the Department of Defense.

(2) Identify, enhance, and transfer knowledge, skills, and direct experience with respect to all phases of the joint 

nuclear weapons life cycle process from one generation of nuclear weapon designers and engineers to the following 

generation.

(3) Periodically demonstrate stockpile responsiveness throughout the range of capabilities required, including 

prototypes, flight testing, and development of plans for certification without the need for nuclear explosive testing.

(4) Shorten design, certification, and manufacturing cycles and timelines to minimize the amount of time and costs 

leading to an engineering prototype and production.

(5) Continually exercise processes for the integration and coordination of all relevant elements and processes of the 

Administration and the Department of Defense required to ensure stockpile responsiveness.

(6) The retention of the ability, in consultation with the Director of National Intelligence, to assess and develop 

prototype nuclear weapons of foreign countries and, if necessary, to conduct no-yield testing of those prototypes.

(d) Joint nuclear weapons life cycle process defined

In this section, the term “joint nuclear weapons life cycle process” means the process developed and maintained by the 

Secretary of Defense and the Secretary of Energy for the development, production, maintenance, and retirement of 

nuclear weapons.

A.10 Related Legislation: S. 4049 NDAA for Fiscal Year 2021

S. 4049 NDAA for FY 2021

§ 3153. MONITORING OF INDUSTRIAL BASE FOR NUCLEAR WEAPONS COMPONENTS, SUBSYSTEMS, AND MATERIALS.

(a) DESIGNATION OF OFFICIAL.—Not later than March 1, 2021, the Administrator for Nuclear Security shall designate a 

senior official within the National Nuclear Security Administration to be responsible for monitoring the industrial base that 

supports the nuclear weapons components, subsystems, and materials of the Administration, including—

(1) the consistent monitoring of the current status of the industrial base;

(2) tracking of industrial base issues over time; and 

(3) proactively identifying gaps or risks in specific areas relating to the industrial base.

(b) PROVISION OF RESOURCES.—The Administrator shall ensure that the official designated under subsection (a) is provided 

with resources sufficient to conduct the monitoring required by that subsection.

(c) CONSULTATIONS.—The Administrator, acting through the official designated under subsection (a), shall, to the extent 

practicable and beneficial, in conducting the monitoring required by that subsection, consult with—

(1) officials of the Department of Defense who are members of the Nuclear Weapons Council established under 

section 179 of title 10, United States Code;

(2) officials of the Department of Defense responsible for the defense industrial base; and

(3) other components of the Department of Energy that rely on similar components, subsystems, or materials.
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S. 4049 NDAA for FY 2021

(d) BRIEFINGS.—

(1) INITIAL BRIEFING.—Not later than April 1, 2021, the Administrator shall provide to the Committees on Armed 

Services of the Senate and the House of Representatives a briefing on the designation of the official required by 

subsection (a), including on—

(A) the responsibilities assigned to that official; and

(B) the plan for providing that official with resources sufficient to conduct the monitoring required by 

subsection (a).

(2) SUBSEQUENT BRIEFINGS.—Not later than April 1, 2022, and annually thereafter through 2024, the Administrator 

shall provide to the Committees on Armed Services of the Senate and the House of Representatives a briefing on 

activities carried out under this section that includes an assessment of the progress made by the official designated 

under subsection (a) in conducting the monitoring required by that subsection.

The committee notes that the NNSA industrial base shares many of the same challenges faced by that of the 

Department of Defense (DOD): parts and materials are procured in small quantities, at irregular intervals, and with 

exacting performance specifications. Unlike the DOD, however, the NNSA does not comprehensively monitor the 

health of its industrial base and instead has left this responsibility to individual programs or contractors. As a result, 

efforts are fragmented and duplicative, as identified by the Department of Energy Inspector General in a July 2018 

report titled ‘‘Supplier Quality Management at National Nuclear Security Administration Sites’’ (DOE–IG–18–41). The 

committee believes that this provision would help the NNSA reduce cost, schedule, and performance risk in future 

programs.

A.11 Related Legislation: S. 1605A NDAA for Fiscal Year 2022

S. 1605A for FY 2022 NDAA

FY 2023

Response

FY 2024 

Response

§ 3135. Reports on risks to and gaps in industrial base for nuclear weapons 

components, subsystems, and materials

N/A Unclassified

Appendix E

Section 3113 of the William M. (Mac) Thornberry National Defense Authorization Act 

for Fiscal Year 2021 (Public Law 116– 283; 50 U.S.C. 2512 note) is amended by adding 

at the end the following new subsection: ‘‘(e) REPORTS.—The Administrator, acting 

through the official designated under subsection (a), shall submit to the Committees 

on Armed Services of the Senate and the House of Representatives, 

contemporaneously with each briefing required by subsection (d)(2), a report— ‘‘(1) 

identifying actual or potential risks to or specific gaps in any element of the industrial 

base that supports the nuclear weapons components, subsystems, or materials of 

the National Nuclear Security Administration; ‘‘(2) describing the actions the 

Administration is taking to further assess, characterize, and prioritize such risks and 

gaps; ‘‘(3) describing mitigating actions, if any, the Administration has underway or 

planned to mitigate any such risks or gaps; ‘‘(4) setting forth the anticipated 

timelines and resources needed for such mitigating actions; and ‘‘(5) describing the 

nature of any coordination with or burden sharing by other departments or agencies 

of the Federal 
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Appendix B

Weapons Activities Capabilities

This appendix describes the breadth of capabilities maintained by Weapons Activities programs in the 

Department of Energy’s National Nuclear Security Administration (DOE/NNSA) nuclear security enterprise

to execute the stockpile mission. These capabilities should not be viewed in isolation or as mutually 

exclusive, as many overlap and are complementary. They represent the underlying disciplines, activities, 

and specialized skills required to meet DOE/NNSA missions. In this document, the capabilities are grouped 

into seven interdependent areas, each of which constitutes a major facet of Weapons Activities work. In 

part, this appendix supports the legislative requirements listed in Appendix A.

As part of its portfolio management approach for Weapons Activities, DOE/NNSA continuously evaluates 

the health of the Weapons Activities capabilities, which are comprised of four elements:

◼ Human capital (experience, skill, people)

◼ Physical assets (facilities, infrastructure, equipment)

◼ Resources (resources, materials)

◼ Enabling processes (knowledge, technology, processes)

All four elements must be sustained and modernized to meet current and future missions. If any of these 

elements are missing, the capabilities cannot function as a system.

B.1 Weapon Science and Engineering

The Weapon Science and Engineering area includes the suite of physical sciences and engineering 

disciplines that comprise the theoretical and experimental capabilities necessary to assess the current 

nuclear stockpile and certify warheads for the future stockpile.

Capability Definition

Atomic Physics, Nuclear Physics,

Nuclear Engineering, and 

Radiochemistry

Atomic physics is the study of atomic systems, such as a collection of atoms and 

electrons, and their interaction with X-rays. The extremely high temperatures 

of functioning nuclear weapons generate X-rays. Nuclear physics is the study of 

atomic nuclei and their constituents and nuclear engineering is the translation

of nuclear physics principles to the practical application of nuclear interactions, 

especially fission and fusion. The need to understand the design and function 

of the nuclear explosive package drives the requirement to improve 

understanding of both fission and fusion, which requires new experimental data 

from the Los Alamos Neutron Science Center (LANSCE). Radiochemistry is the 

study of radioactive materials and their interactions. It is critical to evaluating 

data from legacy underground testing, as well as modeling problems in nuclear 

forensics and attribution. Thermonuclear fusion experiments at the National 

Ignition Facility (NIF), Omega Laser Facility (Omega), and Z pulsed power facility 

(Z) can use radiochemical tracers in their diagnostic suites.
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Capability Definition

Materials Science, High 

Explosives and Energetics 

Science, Chemistry, and 

Actinide Science

Materials science, in this context of stockpile stewardship, is the study of how 

materials in a nuclear weapon are produced, age, and are replaced. Chemistry 

studies the elemental composition, structure, bonding, and properties of 

matter. The stability of material properties, and the nature of reactions, and 

interactions are critical components of system aging studies. How materials 

and properties change with time must be understood to ensure reliability and 

safety of the stockpile. Strength, aging, compatibility, viability, and damage 

mechanics are among the materials characteristics to be evaluated. Materials 

science and chemistry play a key role in resolving stockpile and production 

issues, validating computational models, and developing new materials (e.g., 

materials produced through additive manufacturing). Actinide science is the 

study of physics and chemistry of elements from actinium to lawrencium; it is 

useful to understand production, purification, compatibility, targets, and 

behavior of actinide materials relevant to the stockpile. This section also 

includes high explosives and energetics science and engineering, which are the 

study of detonation and deflagration physics, shock wave propagation, and 

reaction initiation. It includes the design, synthesis, manufacture, inspection, 

testing and evaluation of high explosives and other energetic materials and 

components for specific applications. Knowledge of these materials is 

necessary for understanding nuclear weapon performance. Data required to 

advance and underpin this knowledge is obtained from LANSCE and national 

light source facilities.

High Energy Density Science and

Plasma Physics

High energy density science is the study of matter and radiation under extreme 

conditions such as those in a functioning nuclear weapon and reproduced in 

high-temperature experiments. Plasma physics is the study of systems 

containing separate ions and electrons that exhibit a collective behavior. The 

extremely high temperatures of functioning nuclear weapons generate plasma. 

Facilities such as NIF, Omega, and Z generate high energy density states 

producing data exploring the physical processes that occur in plasma states to 

validate computational models.

Technologies for Creating 

Extreme Conditions (lasers, 

accelerators, pulsed power)

This capability area includes laser, pulsed power, and accelerator technologies 

that are focused on creating extreme conditions, under which to study 

weapons-relevant matter and radiation behavior. Lasers are coherent light 

sources delivering intense beams of energy to localized regions to generate and 

probe high energy density conditions similar to those produced during nuclear 

weapon operation. A laser’s rapid energy delivery enables studies of 

fundamental properties of matter, radiation transport, hydrodynamics and 

turbulence, thermonuclear ignition and burn, as well as outputs and effects. 

Pulsed power devices accumulate energy over long periods of time and release 

it rapidly to generate extreme pressures, temperatures, and radiation 

conditions. Accelerators use electromagnetic fields to accelerate charged 

particles to the velocities needed to generate high-energy X-rays, protons, or 

neutrons. The resulting emissions are sources for advanced imaging, 

investigating nuclear physics phenomena, or simulating weapons outputs and 

hostile environments. Advancements in these areas produce data critical to 

understanding physical phenomena, qualifying nuclear weapon components, 

and improving performance assessments. Facilities include NIF, Omega, 

LANSCE, and Z.
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Capability Definition

Advanced Experimental 

Diagnostics and Sensors

Advanced diagnostics and sensors provide detailed measurements of materials, 

objects, and dynamic processes that are critical to weapon operation and other 

national security operations. Standard diagnostics provide lower-resolution 

data suitable for basic inquiries, but not for detailed part, process, or physics 

qualification; continued diagnostic and sensor development is important to 

addressing these limitations. An example of an advanced diagnostic is static or 

multi-frame dynamic radiography at high resolution. Radiography is an imaging 

technique that uses X-rays or subatomic particles (e.g., protons, neutrons) to 

view the internal structure of an object that is opaque to visible light. Static 

radiography of a stationary object is used during the post-fabrication inspection 

process to ensure components are defect-free and meet exacting quality 

requirements. Dynamic radiography takes multiple images of a dynamic 

process to examine physical behavior in progress.

Hydrodynamic and Subcritical 

Experiments

Hydrodynamic experiments explore implosion physics and provide data on the 

behavior of full-scale dynamic systems. Subcritical experiments are driven by 

high explosives and contain special nuclear material (SNM) that never achieves 

a critical configuration and does not create nuclear yield. Both types of 

experiments provide data that are essential to validating models within multiphysics design codes and predicting nuclear weapon performance.

B.2 Weapon Simulation and Computing

The Weapon Simulation and Computing area includes high-performance computers, weapons codes, 

models, and data analytics used to assess the behavior of nuclear weapons and components. It must 

support calculations of sufficient resolution and complexity to simulate and assess the behavior of weapon 

systems, components, and fundamental science processes that are critical to nuclear weapon 

performance.

Capability Definition

High-performance Computing High-performance computing (HPC) encompasses software, hardware, and 

facilities of sufficient power to achieve the dimensionality, resolution, and 

complexity in simulation codes to accurately model the performance of 

weapon systems and components and the fundamental physical processes 

that are critical to nuclear operation. This capability includes research and 

development (R&D) in computer, information, and mathematical sciences to 

support developing and operating HPC.

Simulation Capabilities for 

Weapon Science, Engineering, and 

Physics

Advanced computer codes, models, and data analytics are used to simulate 

and assess the behavior of nuclear weapons and their components. Codes 

range in application from design of systems to fundamental science 

processes. DOE/NNSA codes operate on computers ranging from desktop 

machines to the world’s largest high-performance supercomputers.

B.3 Weapon Design and Integration

The Weapon Design and Integration area encompasses the capabilities needed to design, test, analyze, 

qualify, and integrate components and subsystems into weapon systems that will meet all military 

requirements and endure all predicted environments to validate and verify that they will always work as 

expected and never work when not intended.
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Capability Definition

Weapons Physics Design and 

Analysis

Design and analysis of the nuclear explosive package is required to maintain 

existing U.S. nuclear weapons; modernize the stockpile; evaluate possible 

proliferant nuclear weapons; and respond to emerging threats, unanticipated 

events, and technological innovation. Elements of design capability include 

concept exploration, conceptual design, requirements satisfaction, detailed 

design and development, production, process development, certification, and 

qualification. Weapons physics analysis includes evaluation of weapons 

effects.

Weapons Engineering Design, 

Analysis, and Integration

Elements of weapons engineering include the following lifecycle phases: 

concept exploration, requirements satisfaction, conceptual design, detailed 

design and development, production, certification, and qualification. This 

capability also encompasses systems integration, which includes 

understanding and developing the interfaces among the non-nuclear 

subsystems, between the non-nuclear components and the nuclear 

explosives package, and between DOE/NNSA and Department of Defense 

(DoD) systems.

Environmental Effects Analysis, 

Testing, and Engineering Sciences

Environmental effects analysis, testing, and engineering sciences use an array 

of test equipment, tools, and techniques to create stockpile-to-target 

sequence conditions and measure the ensuing response of materials, 

components, and systems. Examples of environmental testing (normal, 

hostile, and abnormal) include shock, vibration, radiation, acceleration, 

temperature, electrostatics, and pressure conditions. The engineering 

sciences that support this analysis include thermal and fluid sciences, 

structural mechanics, dynamics, aerodynamics, and electromagnetics.

Weapons Surety Design, Testing, 

Analysis, and Manufacturing

Weapons surety design, analysis, integration, and manufacturing employ a 

variety of safety and use control systems to prevent accidental nuclear 

detonation and unauthorized use of nuclear weapons to ensure a safe and 

secure stockpile. This knowledge, infrastructure, and equipment requires 

strict classification control and secure facilities.

Radiation-Hardened 

Microelectronics Design and 

Manufacturing

Research, design, production, and testing of radiation-hardened 

microelectronics is required for nuclear weapons to function properly in 

hostile environments. This capability requires a secure, trusted supply chain, 

including quality control of the materials used in the process and products.

B.4 Weapon Material Processing and Manufacturing

The Weapon Material Processing and Manufacturing area covers the packaging, processing, handling, 

and/or manufacture of plutonium, uranium, tritium, energetic and hazardous materials, lithium, and 

other metal and organic materials needed for nuclear weapons.

Capability Definition

Plutonium Management Components that contain plutonium require special conduct of operations, 

physical security protection, facilities, and equipment to handle, package, 

process, manufacture, and inspect these components.

Uranium Management Components that contain enriched and depleted uranium require special 

conduct of operations, physical security protection, facilities, and equipment 

to handle, package, process, manufacture, and inspect these components.
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Capability Definition

Tritium Management Tritium has a 12-year half-life and must be periodically replenished in gas 

transfer systems (GTS). Tritium is produced by irradiating tritium-producing 

burnable absorber rods (TPBARs) in Tennessee Valley Authority’s Watts Bar 

nuclear reactors. Handling and processing of tritium includes transporting 

TPBARs to the Savannah River Site and extracting tritium from the TPBARS, as 

well as purifying, storing, and loading the tritium into GTS reservoirs and 

inspecting reservoirs. Tritium is also recovered from returned GTSs.

High Explosives and Energetics 

Management

Development and production of energetics, including the associated 

manufacturing processes and infrastructure modernization to meet legacy 

and modernization stockpile applications. Energetics are materials that 

provide instantaneous energy through an exothermic chemical reaction. 

Energetics include specific end products, such as high explosives 

(conventional and insensitive) low explosives (pyrotechnics and propellants), 

their respective energetic ingredients, and various inert ingredients required 

for manufacturing (e.g., polymers, reactants, catalysts, plasticizers, oxidizers, 

fuels, ballistic modifiers, stabilizers, surfactants, and bonding agents).

Lithium Management Components that contain lithium materials require special conduct of 

operations, physical security protection, facilities, and equipment to handle, 

package, process, manufacture, and inspect these components.

Additional Material Needs Specialized components and materials that are not commercially available 

must be produced within the nuclear security enterprise. This production 

may require synthesis of organic materials and processing, manufacturing, 

and inspection of metallic and organic products, based on knowledge of 

material behavior, compatibility, and aging, which would include, but is not 

limited to, polymer material and part manufacturing.

B.5 Weapon Component Production

The Weapon Component Production area includes the core capabilities for producing all of the 

components and systems required to arm, fuze, fire, and deliver nuclear weapons to their target. The 

Weapon Component Production area includes the capabilities for producing all of the non-nuclear 

components and systems for weaponization of the nuclear explosive package. These functions enable the 

weapons to arm, fuze, and fire for the designed function when needed. This capability includes both 

internal and external manufacturing and a broad supply base, as well as identification and verification of 

trusted suppliers to provide materials and parts within the weapon product realization process.

Capability Definition

Non-Nuclear Component 

Modernization and Production

Non-nuclear weapon components and assembly processes require special 

manufacturing, assembly, and inspection protocols. The components include, 

but are not limited to, cable assemblies; electronic assemblies; 

microelectronics packaging; GTSs; arming, fuzing, and firing assemblies; 

lightning arrestor connectors; environmental sensing devices; radars; neutron 

generators; and power sources.

Weapon Component and Material 

Process Development

Process development of weapon components involves small-lot production, 

precise controls, and a deep understanding of the hazards of working with 

SNM and other exotic materials. Component process development is needed 

whenever process changes are made to reduce costs or production time.
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Capability Definition

Weapon Component and System 

Prototyping

Development, qualification, and manufacture of high-fidelity, full-scale 

prototype weapon components and systems reduce costs and lifecycle time 

to develop and qualify new designs and technologies. This capability includes 

the ability to design, manufacture, and employ mockups with sensors to 

support laboratory and flight tests that provide evidence that components 

can function with DoD delivery systems in realistic environments. 

Advanced Manufacturing Advanced manufacturing uses innovative techniques from industry, 

academia, or internal R&D to reduce costs, reduce component development 

and production time, improve safety and performance, and control waste 

streams. Examples include additive manufacturing, use of microreactors, 

microwave casting, and electrorefining.

B.6 Weapon Assembly, Storage, Testing, and Disposition

After weapon components are produced, each requires assembly into complete warheads and temporary 

storage before delivery to DoD. Some of these warheads are removed from the stockpile on an annual

basis for surveillance to provide data to evaluate the health of the stockpile. These surveillance activities 

(such as inspections, laboratory and flight tests, nondestructive tests, and component and material 

evaluations) provide data over time to predict, detect, assess, and resolve aging trends and any observed 

anomalies. This process requires disassembly and sometimes reassembly. At their end of life, or for other 

reasons, nuclear weapons undergo disposition. The Weapon Assembly, Storage, Testing, and Disposition 

area covers all these capabilities.

Capability Definition

Weapon Assembly, Storage, and 

Disposition

This capability includes assembly and disassembly of all warheads, including 

components and subsystems contained within a device, and encompasses the 

breadth of national security enterprise capabilities requiring special conduct 

of operations, equipment, facilities, and quality control. Disassembly, 

inspection, and disposition of the warhead, components, and subsystems 

requires similar special conduct of operations, equipment, and facilities. 

Storage of weapons and subsystems requires special safety and security 

processes and protocols.

Testing Equipment Design and 

Fabrication

Design and fabrication of special test equipment to simulate environmental 

and functional conditions ensure that products meet specifications. Data 

from test equipment provide evidence for qualification, certification, 

reliability, surety, and surveillance. 

Weapon Component and System 

Surveillance and Assessment

Surveillance enhances integration across test regimes to demonstrate 

performance requirements for stockpile systems by inspections, laboratory 

and flight tests, nondestructive tests, and component and material 

evaluations. Comparing data over time provides the ability to predict, detect, 

assess, and resolve aging trends and anomalous changes in the stockpile and 

address or mitigate issues or concerns. Assessment is the analysis, largely 

through modeling and simulation, of data gathered during surveillance to 

evaluate the safety, performance, and reliability of weapon systems and the 

effect of aging on performance, uncertainties, and margins.
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B.7 Transportation and Security

The Transportation and Security area involves DOE/NNSA’s capabilities for protecting the people, places, 

information, and other items and processes critical to the function of the nuclear security enterprise.

Capability Definition

Secure Transportation Protection and movement of nuclear weapons, weapon components, and 

SNM between facilities includes design and fabrication or modification of 

vehicles, design and fabrication of special communication systems, and 

training of Federal agents. 

Physical Security Physical security protects the Nation’s nuclear materials, infrastructure 

assets, and workforce at DOE/NNSA sites involved in Weapons Activities. It 

protects assets from theft, diversion, sabotage, espionage, unauthorized 

access, compromise, and other hostile or noncompliant acts that may 

adversely affect national security, program continuity, and employee security.

Information Technology and 

Cybersecurity

Information technology and cybersecurity provides infrastructure and 

protection for computing networks, secure communications, applications, 

systems, and logical environments. It ensures electronic information and 

information assets are operating nominally and are protected from 

unauthorized access and malicious acts that would adversely affect national 

and economic security.
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Appendix C

Exascale

The United States must retain state-of-the-art capabilities in high-performance computing (HPC) to 

maintain competitive advantage and perform the annual stockpile assessment. HPC will support U.S. 

national security, economic prosperity, technological strength, and scientific and energy research 

leadership. Failure to apply HPC to national security, science, and growing big data needs will open the 

door for other nations with a demonstrated commitment to HPC investment to take the lead in several

critical areas. Risk to U.S. leadership in high-end computing would increase, and could also eventually

increase in science, national defense, energy innovation, and the commercial computing market (see 

Figure C–1).

Figure C–1. Overview of the DOE/NNSA Exascale Computing Initiative

The National Strategic Computing Initiative was established as a Federal interagency campaign in 2015

and updated in 2019 to maximize the benefits of HPC for U.S. economic competitiveness, scientific 

discovery, and national security. Other agencies with major responsibilities for the Initiative include the 

National Science Foundation, the intelligence community, and the Departments of Commerce, Defense, 

Justice, and Homeland Security. The National Strategic Computing Initiative’s major focus areas are the 

exploration and development of quantum computing, bio computing, and exascale computing. Within 

this initiative, the Department of Energy (DOE), represented by a partnership between the DOE Office of 
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Science and DOE’s National Nuclear Security Administration (DOE/NNSA), has the lead responsibility for 

focusing and implementing the joint Exascale Computing Initiative (ECI). This initiative focuses on 

advanced simulation that continues exploiting MOSFET1technology to emphasize sustained HPC to 

advance DOE/NNSA missions. The objectives and the associated scientific challenges define a mission 

need for a computing capability of 2 to 10 exaFLOPS2in the early to mid-2020s.

C.1 Challenges

To deliver the exascale computing capability for the nuclear security mission within the next decade while 

maintaining and modifying the integrated design codes (IDCs), DOE/NNSA will need to focus on six 

challenges:

◼ Developing HPC technologies and systems, in close partnership with computer vendors, that will 

provide at least an eight-fold increase in sustained application code performance over the 

currently largest NNSA supercomputer (a 125-petaFLOPS3system).

◼ Addressing code performance on the current advanced architecture and next-generation 

systems, which employ heterogeneous architectures that are very different from the 

homogeneous computing environment DOE/NNSA has experienced in the past two decades.

◼ Advancing the Advanced Simulation and Computing (ASC) program-funded laboratory and 

open-source software stack to run efficiently on the new advanced architectures and to support 

emerging workflows.

◼ Developing prototype systems to assess the viability of alternate HPC architecture paths for ASC.

◼ Improving remote computing infrastructure to facilitate access across the DOE/NNSA complex to 

exascale and other leading-edge platforms wherever each may be sited.

◼ Modernizing DOE/NNSA computing facilities to prepare them for siting future petascale and 

exascale platforms through increasing structural integrity, power, and cooling capabilities.

C.2 Approaches and Strategies

The U.S. Government has been interacting with industry in HPC technology development to achieve 

DOE/NNSA’s exascale goals. Past partnerships between the U.S. Government and industry have led to 

development of innovative technologies that met Federal and private sector objectives. DOE/NNSA is 

continuing its partnership with the DOE Office of Science on the ECI, including investments in research 

and development of hardware and systems technologies, software tools, and applications with computer 

vendors, the national laboratories, and universities. In addition, the two organizations collaborated on 

the joint April 2018 CORAL-2 procurement, which delivered one exascale-class system to DOE’s Office of 

Science in fiscal year (FY) 2021–2022 and will deliver another to DOE/NNSA in FY 2023. This joint 

procurement greatly supports the two organizations as they leverage each other’s critical non-recurring 

engineering development costs and jointly manage the technical progress of the two exascale system 

projects. 

1 MOSFET stands for metal-oxide semiconductor, field-effect transistor. This technology, which has been the incumbent 

technology associated with Moore’s law in microelectronics since the 1960s, theoretically begins failing significantly at speeds 

faster than exascale speeds.

2 1 exaFLOPS = 1018 floating-point operations per second.

3 1 petaFLOPS = 1015 floating-point operations per second.
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The FY 2024 spend plan for ECI elements is delineated in Table C–1. In FY 2024, the DOE/NNSA portion 

of the ECI spans across four ASC program elements: Integrated Codes; Physics and Engineering Models; 

Verification and Validation, which fund the next-generation simulation technologies for the weapons 

mission (or the Defense Applications and Modeling portfolio); and Computational Systems and Software 

Environment subprogram, which deploys the next-generation system software stack and procures the 

El Capitan system. 

Table C–1. NNSA Exascale Computing Initiative funding schedule for FY 2024

Exascale Computing Initiative Elements

FY 2024 Request

(dollars in millions)

FY 2016-2024 Totals

(dollars in millions)

Defense Applications and Modeling 18 82

Computational Systems and Software Environment 15 79

El Capitan Procurement 130 542

Advanced Technology Development and Mitigation 0 630

Facility Operations and User Support 0 20

Exascale Computing Facility Modernization 0 105

Total, NNSA Exascale Initiative 163 1,458

Defense Application and Modeling – Next-Generation Application Development

In FY 2021, DOE/NNSA began transitioning the validated next-generation code and associated capabilities 

into its Integrated Codes, Physics and Engineering Modeling, and Verification and Validation subprograms 

to support the annual assessment activities. 

Computational Systems and Software Environment – Next-Generation Computing Technologies

In FY 2024, DOE/NNSA will transition the next-generation computing technology activities to 

Computational Systems and Software Environment subprogram. DOE/NNSA will continue evaluating its 

next-generation IDC performance portability on advanced architecture prototype systems. Funding will 

be for development, maintenance, and user support for the DOE/NNSA tri-laboratory software stack that 

will be required for the next-generation codes to run efficiently on these advanced technology systems. 

In addition, DOE/NNSA will continue investing in the application of advanced machine learning 

techniques, which are well-suited to the imminent advanced architectures, to address stockpile 

stewardship challenges. 

Computational Systems and Software Environment – El Capitan Procurement

DOE/NNSA has been embarking on a multi-year collaboration with the selected system vendor and its 

subcontractors to work on non-recurring engineering and system integration to deliver El Capitan. The 

collaboration focuses on system engineering efforts and software technologies to assure the 2024

exascale system will be a capable and productive computing resource for the Stockpile Stewardship 

Program. 

C.3 Collaborative Management

As the Exascale Computing Project (ECP) spans across DOE/NNSA, its management equally involves both 

organizations’ Federal and laboratory personnel. The ECP overall management structure includes the 

Integrated Project Team in Figure C–2. The Integrated Project Team provides planning, execution, 

coordination, and communication for the ECP to ensure the project’s objectives are achieved on schedule 

and within budget and are consistent with quality, environment, safety, and health standards. 
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Figure C–2. Exascale Computing Project integrated project team

C.4 Milestones

DOE/NNSA has five milestones for FY 2024:

◼ Collaborate with DOE Office of Science on the close-out of the 7-year ECP

◼ Transition ASC’s next-generation computing software technologies to its Computational Systems 

and Software Environment portfolio

◼ Continue porting additional IDCs to RZVernal, which is the classified El Capitan early access 

system-3 nodes, to analyze potential performance issues that may occur on El Capitan

◼ Collaborate with the El Capitan platform vendor on the full system’s deployment and acceptance 

at Lawrence Livermore National Laboratory

◼ Transition El Capitan to classified computing environment

C.5 Conclusion

DOE/NNSA, through the ASC exascale computing effort, is investing in products and approaches that will 

respond directly to anticipated disruptive changes in the HPC ecosystem. Activities include creating

research and development partnerships with multiple HPC vendors, developing next-generation weapons 

codes with new simulation capabilities, advancing the tri-laboratory software stack, procuring an exascale 

system, deploying prototype systems to assess the viability of new computing technologies, and 

upgrading facilities to house future exascale and petascale systems. Collaboration projects with computer 

vendors have also led to significant advances in HPC software and hardware technologies. These activities 

have provided valuable lessons learned and delivered numerous software development tools and libraries 

that many ASC applications and the broader U.S. HPC community now rely heavily on. Research, 

development, and engineering efforts will continue in 2024 and beyond for DOE/NNSA to optimally utilize

the exascale computing capability, integrated with AI/ML and data analytics technologies, to address 

Defense Programs’ mission needs.
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Appendix D

Stockpile Responsiveness Program

This appendix is provided pursuant to 50 United States (U.S.) Code § 2523, which requires inclusion of 

plans for the Stockpile Responsiveness Program (SRP) in the Stockpile Stewardship and Management Plan

(SSMP). 

Section 3112 of the National Defense Authorization Act for Fiscal Year 2016 established that “[i]t is the 

policy of the United States to identify, sustain, enhance, integrate, and continually exercise all capabilities 

required to conceptualize, study, design, develop, engineer, certify, produce, and deploy nuclear weapons 

to ensure the nuclear deterrent of the United States remains safe, secure, reliable, credible, and 

responsive.” Section 3112 created the SRP to achieve this policy in coordination with already existing 

Stockpile Stewardship and Stockpile Management Programs.

SRP is intended to exercise and enhance capabilities through the entire nuclear weapons lifecycle to 

improve the responsiveness of the United States to future threats, technology trends, and international 

developments not addressed by existing life extension programs. Technology development teams also 

provide leadership opportunities for early-career staff members while SRP activities fully exercise the 

abilities of the workforce and allow the enterprise to identify efficiencies for current and future programs. 

SRP is organized according to major technical efforts and heavily focuses on improving production 

responsiveness along with joint activities with the Office of the Under Secretary of Defense for Research 

and Engineering. The SRP report provides information regarding the program’s purpose, planned budget, 

governance, and priorities.

H. Rept. 117-98 accompanying the Energy and Water Development and Related Agencies Appropriations 

Bill, 2022, restated an annual SRP reporting requirement and noted that since the SSMP does not typically 

accompany the annual budget request, including the report within the SSMP, it “therefore does not offer 

a useful and timely companion to the budget.” This direction was reiterated through the Joint Explanatory 

Statement accompanying the Energy and Water Development and Related Agencies Appropriations Act, 

2022. Therefore, in accordance with this direction, the Department of Energy’s National Nuclear Security 

Administration submitted the report most recently as a standalone document in July 2023 to provide as 

timely updates as possible. (See Status of and Plans for Projects and Activities within the Stockpile 

Responsiveness Program, 2023 Annual Report.)
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Appendix E

Industrial Base

E.1 Framework

The nuclear security enterprise industrial base (NIB) is the global industrial capacity and capability that 

enables research and development, design, production, shipping, sustainment, and modernization of 

nuclear weapons components, subsystems, and materials to support the U.S. nuclear deterrent. The 

Department of Energy’s National Nuclear Security Administration (DOE/NNSA) monitors the NIB through 

a framework consisting of four pillars: supply chain, operations and facilities, logistics and transportation, 

and workforce. DOE/NNSA uses these pillars to identify the full scope of industrial base challenges to 

maintaining the nuclear stockpile, including those that are internal to the nuclear security enterprise, such 

as material production and workforce management, and external, such as vendor resiliency. DOE/NNSA 

stands apart from many other U.S. Departments and Agencies in that through its laboratories, plants, and 

sites, it is a producer and consumer of manufactured goods. The activities listed under the pillars in 

Figure E–1 indicate the types of activities that are considered when examining the NIB. 

Figure E–1. The nuclear security enterprise industrial base framework
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E.2 Risk Management

Risk management is an area of increased attention across the nuclear security enterprise. Programs and 

sites within the enterprise employ varying risk management methods to identify, characterize, monitor, 

and manage risks, including tracking and monitoring global events to identify emerging risks to the 

enterprise. These efforts include program-specific risk matrices, supply chain-focused risk matrices (which 

track risks from raw material procurements through product acceptance), and implementation of supplier 

transparency software for a more proactive approach to supply chain risk management. There are also

significant efforts underway to standardize the methods used for risk management, such as the Supply 

Chain Risk Management Team, which is working to standardize the methods used to identify, monitor, 

and respond to supply chain risks across the nuclear security enterprise. The Supply Chain Risk 

Management Team supports larger DOE/NNSA initiatives that address all the pillars of the NIB to create 

an overarching process to make risk management practices more rigorous. There are many risk factors 

that can affect the DOE/NNSA’s ability to provide continued viability of the nuclear weapons stockpile. 

Consequently, these factors are not unique to the nuclear security enterprise, as they affect all industry 

sectors (i.e., government and commercial). Examples of these are listed in Table E–1.

Table E–1. The nuclear security industrial base risk factors

Human Capital Gaps Industry is unable to hire or retain U.S. workers with the necessary skill sets

Sole Source Vendors Only one supplier is qualified to provide the required capability and/ or product

Constrained Market Capacity is unavailable in required quantities or time due to competing market demands

Product Security Lack of cyber and physical protection results in eroding integrity and confidence

Sunset Technologies Product or material obsolescence resulting from decline in relevant suppliers

Foreign Dependency Domestic industry does not produce the product, or does not produce in sufficient quantities

Eroding Infrastructure Loss of specialized capital equipment needed to integrate, manufacture, or maintain capability

Regulatory Changes Labor, environmental, transportation, etc., laws outpace industry’s ability to develop alternative 

processes

Inflation Changes to the global market causing uncertainty in suppliers pricing models thereby increase 

costs in material, labor, and freight over a short period of time

Global Events Both manmade and natural events such as the war in Ukraine and the COVID-19 pandemic that 

negatively impact the supplies of critical goods and services

COVID-19 = Coronavirus Disease 2019

E.2.1 Monitoring

The NIB is complex and multi-faceted. Many diverse groups within the enterprise monitor and act on 

industrial base issues that are specific to their own programs or activities, which does not always allow 

for a broad view of the industrial base. Therefore, DOE/NNSA leverages its Integrated Planning Group to 

increase data sharing across various program offices, and monitors more than 80 active working groups 

both internal and external to the nuclear security enterprise to improve coordination and collaboration. 

In addition, information sharing occurs across the enterprise with specific emphasis in areas such as risk 

management and issues related to supply chain assurance.
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E.2.2 Mitigation

Within the Stockpile Stewardship and Management Plan, each of the four NIB pillars are addressed in 

additional detail in their relevant sections along with actual or potential challenges (risks) and mitigation 

strategies. While not a complete index of references, some examples are:

◼ Supply Chain challenges are discussed throughout but primarily in Chapter 3, “Production 

Modernization.” Specific examples of supply chain challenges discussed include managing 

glovebox fabrication and deliveries, developing sufficient capacity for energetic materials, 

maintaining a reliable tritium supply chain, and supply chain disruptions affecting a range of 

microelectronic materials.

◼ Operations and Facilities challenges are discussed primarily in Chapter 3, “Production 

Modernization”; Chapter 4, “Stockpile Research, Technology, and Engineering”; and Chapter 6, 

“Infrastructure and Operations.” Specific examples of operations and facilities challenges include 

issues stemming from outdated and aging infrastructure, the need to invest in both modern 

infrastructure and emerging technology, and lack of capacity to meet emerging mission 

requirements.

◼ Logistics and Transportation challenges are primarily discussed in Chapter 2, “Stockpile 

Management,” Chapter 5, “Security,” and Appendix B, Section B.7, “Transportation and Security.”

Specific examples of logistics and transportation challenges include sustaining the Safeguards 

Transporter fleet, manufacturability, and sourcing limitations of future secure transportation 

programs. These could increase cost and scheduling risks.

◼ Workforce challenges are primarily discussed in Chapter 7, “Workforce.” Specific examples of 

challenges to the workforce include DOE/NNSA’S need to hire, train, qualify, and retain additional 

pit production personnel to meet growing requirements, as well as commercial competition and 

increased turnover among key talent in mission critical areas.

E.3 Interagency Coordination

DOE/NNSA participates in numerous Interagency forums to include the Joint Industrial Base Working 

Group, which acts as the advisory committee to the Department of Defense (DoD)-led Industrial Base 

Council. The Council functions as the principal advisory forum on prioritized industrial base matters for 

DoD to ensure industrial base readiness and resiliency. DOE/NNSA provides a representative to the Joint 

Industrial Base Working Group and participates in multiple cross-cutting sector working groups related to 

nuclear weapons. 

DOE is a statutory member of the Committee on Foreign Investment in the United States (CFIUS), an 

interagency committee that reviews certain transactions involving foreign investment in the United States 

to determine the effect of such transactions on the national security of the United States. For each 

transaction subject to CFIUS jurisdiction, the Department of Treasury, as CFIUS Chair, assigns a lead agency 

to review the transaction; DOE is a lead on approximately 25 percent of transaction reviews annually, 

mostly in the energy sector, but with numerous cases impacting the nuclear weapons complex. In 2022, 

the NNSA CFIUS team analyzed 71 foreign acquisitions of U.S. companies with potential ties to the NIB or 

tangentially relevant industries. Of these cases, the NNSA CFIUS team identified and mitigated six major 

foreign acquisitions that threatened the safety and security of the NIB supply chains and operations. 
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Appendix F

Workforce and Site-Specific Information

As detailed in Chapter 1, the Department of Energy’s National Nuclear Security Administration 

(DOE/NNSA) has eight nuclear security enterprise sites, spread across the Nation, that possess the expert 

workforce and advanced capabilities to maintain the Nation’s nuclear deterrent. These eight sites include 

three national security laboratories (Lawrence Livermore National Laboratory [LLNL], Los Alamos National 

Laboratory [LANL], and Sandia National Laboratories [SNL]), four nuclear weapons production facilities 

(Kansas City National Security Complex [KCNSC], Pantex Plant [Pantex], Savannah River Site [SRS], and 

Y-12 National Security Complex [Y-12]), and the Nevada National Security Site (NNSS), as shown in 

Figure F–1. Specific information is included in this appendix to elaborate on each site’s mission, weapon 

activities capabilities, the fiscal year (FY) 2024 budget request, recent accomplishments, and workforce

data. This information is also included for the DOE/NNSA Federal workforce.

Figure F–1. The DOE/NNSA nuclear security enterprise
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Critical Importance of Investing in Advanced Capabilities, Infrastructure, and the Workforce

Planning and investing in advanced capabilities, infrastructure, and most importantly the workforce are 

at the heart of achieving U.S. nuclear security objectives. These aspects are also interrelated.

◼ DOE/NNSA provides decision-makers with capabilities that are modern, robust, flexible, resilient, 

ready, and appropriately tailored to deter 21st century threats, and it continues to modernize and 

improve the capabilities it offers. Advanced capabilities help meet evolving deterrence needs.

◼ Modern stockpile stewardship requires specialized technologies and processes, as demonstrated

by the capabilities that DOE/NNSA requires for mission success (see Appendix B, “Weapons 

Activities Capabilities”). These technologies and processes include, but are not limited to, areas 

such as advanced manufacturing, producing and handling hazardous materials, materials science,

and computer science.

◼ These capabilities, technologies, and processes require purpose-built facilities that can 

successfully contain the necessary work, such as processing lithium compounds or conducting 

experiments on plutonium. These facilities must ensure that the work can be done safely and on 

schedule.

◼ To successfully accomplish the mission, DOE/NNSA and its laboratories, plants, and sites must 

attract, train, and retain a skilled and experienced workforce. The workforce provides the 

knowledge, skills, and abilities to successfully continue Science-Based Stockpile Stewardship and 

to deliver modernized or new nuclear weapons to the Department of Defense (DoD). In pursuit 

of these missions, the workforce across the enterprise must operate state-of the-art 

supercomputers, design and manufacture components, understand how materials will interact, 

and safely operate with hazardous or explosive materials, among many other areas of knowledge 

and skills.

All data shown in this appendix is for FY 2022, unless otherwise noted, using data that was current as of 

September 30, 2022. Employees are counted by headcount.

F.1 National Nuclear Security Administration

F.1.1 Federal Workforce

The Federal workforce plans, manages, and 

oversees the nuclear security enterprise and is 

accountable to the President, Congress, and the 

public. NNSA’s Federal workforce handles 

program and project management for 

DOE/NNSA’s major missions of maintaining the 

nuclear weapons stockpile, naval nuclear 

propulsion, and nuclear threat reduction through 

global material security and nonproliferation. In 

addition to these functions, Federal employees 

also perform important missions in areas such as 

physical security, cyber security, management and human resources, procurement, infrastructure 

planning and budgeting, strategic communications, and public affairs. The Federal workforce operates 

out of Headquarters facilities in Washington, DC; Germantown, Maryland; and Albuquerque, New Mexico. 

Federal staff are also dispersed throughout field offices located at each of the sites; these field offices 

employ subject matter experts in a wide variety of disciplines to provide oversight for each site’s diverse 
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national security missions. NNSA’s Federal workforce, like its contracted management and operating 

(M&O) partners and other non-M&O contractors, is composed of dedicated professionals working to 

promote the nuclear security mission. 

NNSA’s Federal workforce has a fairly even age distribution, with the smallest populations being those 

who recently completed college or graduate school and those who are retirement-eligible, shown below. 

Despite this relatively flat age distribution, the workforce is skewed to fewer years of service, with the 

majority having 0–15 years of service at NNSA. These data reflect aggressive hiring efforts in recent years 

to meet NNSA’s growing mission.

1

1 The number of Federal employees does not include DOE-funded Federal personnel within the Office of Naval Reactors, but does 

contain Federal staff within the Office of Secure Transportation.
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NNSA’s recruitment and outreach strategies include a variety of approaches. NNSA continues to expand 

its relationships with colleges and universities, professional organizations, vocational rehabilitation 

programs, and with organizations representing women, veterans, people with disabilities, and other 

groups. NNSA participates in career fairs sponsored by colleges and universities, professional 

organizations, and other organizations. NNSA also hosts career fairs in which hiring managers interact 

with candidates, conduct job interviews, and make selections. Additionally, NNSA and its M&O partners 

continue to conduct “Nuclear Security Enterprise Days” at colleges and universities, giving students an 

information session followed by the opportunity to directly speak with managers and human resources 

personnel across the enterprise regarding career opportunities. NNSA continues to leverage the National 

Graduate Fellowship Program and Presidential Management Fellows Program to train and develop for 

careers within the nuclear security enterprise. During these programs, Fellows receive training and gain 

hands-on experience, and NNSA extends offers to a majority of the Fellows upon completion of their 

programs. In addition to these fellowship programs, NNSA exposes college students to its unique mission 

through intern programs such as the University of Maryland Program and the Minority-Serving Institution 

Partnership Program. NNSA continues to use professional job boards as well as social media to highlight 

career opportunities and hire top talent.

NNSA has experienced a slight increase in separations over the last few years, as shown by Figure F–2, 

which are evenly split between voluntary separations and retirements. As shown in Figure F–3, most 

voluntary separations occur between 0–5 years of service, while most retirements occur after 26 years of 

service. To retain the top talent it has recruited and hired, NNSA continues to offer a variety of 

developmental programs for employees to include coaching, mentoring, rotations, and the academic 

degree program, as well as sponsoring numerous leadership development programs. To the most feasible 

extent possible, NNSA continues to leverage workforce flexibilities—to include telework, remote work, 

and flexible work schedules—to retain employees. Additionally, NNSA continues to recognize its 

workforce through its pay for performance system and employee recognition programs. NNSA also 

leverages the student loan repayment program to help with retention of its employees.

Figure F–2. Federal workforce employee separation trends
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-5

Figure F–3. Federal workforce separations by years of service

Figure F–4 demonstrates that the Federal workforce is successfully retaining mid- and advanced-career 

employees, though the percentage of advanced career employees has decreased over the last 4 years, 

primarily due to workforce growth. Despite this growth, the number of early career personnel is staying 

relatively constant at about 15 percent. The percent of the workforce eligible for retirement is similarly 

15 percent. NNSA recognizes the opportunity for knowledge preservation and transfer from advanced 

career employees to early and mid-career employees, and has been leveraging those programs. 

Figure F–4. Federal workforce trend over time by stage of career
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-6

F.2 National Security Laboratories

F.2.1 Lawrence Livermore National Laboratory

F.2.1.1 Mission Overview

DOE/NNSA sponsors the Lawrence Livermore National Laboratory (LLNL) Federally Funded Research and 

Development Center. LLNL is uniquely positioned to guide challenging research and development (R&D)

and deliver results to support DOE/NNSA mission needs. LLNL provides research, development, test, and 

evaluation (RDT&E) capabilities for the stockpile, as well as a broad range of national security needs 

integral to the mission and operation of DOE and other Federal agencies. LLNL is managed by Lawrence 

Livermore National Security, LLC.

F.2.1.2 Funding

FY 2024 DOE request – site funding by source

(total LLNL FY 2024 request = $2,359 million)

LLNL split for the FY 2024 Weapons Activities

President’s Budget Request ($1,988 million)
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-7

F.2.1.3 Site Capabilities

LLNL is a DOE/NNSA Center of Excellence for Nuclear Design and Engineering, with core competencies in 

high explosives (HE), high energy density (HED) physics, high-performance computing (HPC), nuclear 

physics, materials science and engineering, and additive manufacturing. LLNL is the lead design agency 

for the W80-4 (the Air Force’s cruise missile warhead) life extension program (LEP) and the W87-1

Modification (Mod) Program. LLNL has primary assessment responsibility for the W80-1, W87-0, B83, and 

W84, as well as review responsibility for other systems.

LLNL operates DOE/NNSA flagship stockpile stewardship facilities including the National Ignition Facility

(NIF), Livermore High Performance Computing Center, Sierra, and the new exascale class El Capitan (both

of which are advanced technology computing systems), High Explosives Applications Facility, Contained 

Firing Facility/Flash X-Ray, National Atmospheric Release Advisory Center, Nuclear Forensics Center, 

Center for Accelerator Mass Spectrometry, materials engineering at Applied Materials and Engineering

Campus, HE testing and development at S300 Energetic Materials Development Enclave Campus, 

advanced manufacturing in the Livermore Valley Open Campus, and Plutonium Superblock. LLNL also 

sustains and advances the physical infrastructure and capabilities supporting R&D, science, and 

technology missions in weapons engineering, design, performance physics, advanced materials, HPC, and 

HED physics. 

LLNL capabilities related to design, development, and sustainment of stockpile systems with their 

associated challenges and strategies are described in Table F–1.

Table F–1. Lawrence Livermore National Laboratory capabilities

Weapons Physics Design and Analysis

LLNL scientists, engineers, and technical staff design, assess, and certify the performance of the nuclear explosive package 

without the need for nuclear testing. This effort is accomplished through implementing advanced computational and 

experimental capabilities that integrate the best available tools and knowledge. LLNL characterizes primary and secondary 

performance, safety, HE, and material properties and develops advanced diagnostics and sensors; laser, pulsed power, and 

accelerator technologies; and hydrodynamic and subcritical experimental platforms.

Challenges Strategies

Improvements in key capabilities are 

required for active and future 

modernization programs, including 

support for increased demand and 

operational tempo at experimental 

facilities; adequately trained workforce 

with consistent knowledge transfer 

across teams; and development of 

advanced diagnostic capabilities, such 

as dynamic radiography, in support of 

nuclear explosive package performance 

certification. 

Current Strategy Being Implemented Future Strategies Needed

DOE/NNSA is investing in infrastructure 

support and recapitalization to modernize 

Site 300 capabilities, including the Flash X-Ray 

and Contained Firing Facility, and in 

plutonium infrastructure and advanced 

diagnostics development to support weapons 

certification.

Production enclave investment ensures 

RDT&E for new materials that support the 

stockpile.

Expand material and component 

test and fabrication capabilities to 

support weapons design and 

certification. 

Continue infrastructure 

investments to improve efficiency 

of facility use.

Partner with other DOE sites to 

expand access and increase 

flexibility for focused-science 

experiments addressing stockpile 

interests.

Weapons Engineering Design, Analysis, and Integration

LLNL is responsible for weaponizing the physics package to ensure effectiveness across the weapon stockpile-to-target sequence 

and safety throughout its complete lifecycle. Engineering design and analysis are core elements of the certification and 

production of weapon modernization programs. Weapons engineering is also critical for the sustainment of fielded weapons, 

including integration with DOE/NNSA, DoD, and production sites; support for surveillance evaluations and ongoing production;

targeted laboratory experiments; and annual assessments of weapon safety and effectiveness. The same weapons engineering 

expertise is used to support design and production of high-fidelity test assemblies used for hydrodynamic and subcritical 

experiments, as well as other high-precision assemblies used to support weapon physics analyses.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-8

Challenges Strategies

LLNL will require continuous 

modernization of warhead test and 

evaluation capabilities and investment 

in upgrading and replacing aging 

facilities, as well as training a new 

generation of staff.

Current Strategy Being Implemented Future Strategies Needed

DOE/NNSA is making multi-year, sustainment 

investments in weapons engineering 

capabilities, including fabrication and 

inspection, nondestructive evaluation, 

environmental testing, plutonium science, 

and radioactive material processing. 

Continue multi-year investments,

including major upgrades to the 

environmental testing complex. 

High Explosives Science and Engineering

LLNL’s HE RDT&E capabilities support stockpile stewardship, nuclear nonproliferation, and nuclear counterterrorism efforts via a 

multidisciplinary approach to synthesis, formulation, characterization, processing, and testing of energetic materials, 

components, and warhead subassemblies. LLNL characterizes HE performance and safety at device and laboratory scales.

Modernization activities support LEP and warhead assessments in facilities and equipment for HE large charge pressing, plotscale synthesis, and formulation systems. LLNL has demonstrated the first-known capability to additively manufacture threedimensional HE structures and has demonstrated their ability to detonate. LLNL holds three Records of Invention in HE additive 

manufacturing technology.

Challenges Strategies

LLNL is responsible for qualifying 

insensitive HE for assigned U.S.

stockpile systems. HE processing 

capabilities require modernization for 

LLNL to meet programmatic demands 

for additional prototyping of warhead 

HE systems and support RDT&E 

capacities and throughputs.

Infrastructure supporting HE pressing 

and machining capabilities needs 

continued condition assessment and 

recapitalization.

Current Strategy Being Implemented Future Strategies Needed

DOE/NNSA is investing in the High Explosives 

Applications Facility and Site 300 

infrastructure through a 5-year program that 

addresses short- and long-term facility 

recapitalization for mission objectives. LLNL 

is developing the Energetic Materials 

Development Enclave Campus, a production 

enclave that will focus on joint material 

development and handling with production 

agencies to deliver increased lot acceptance 

and improved first principles modeling with 

the goal of enhancing performance and safety 

predictions with less experimental 

verification.

Continue investing in HE RDT&E 

capabilities and upgrading and 

revitalizing aging facilities.

High Performance Computing

LLNL’s high performance computing capabilities comprise of a world-class set of computing platforms running highly scalable 

and advanced modeling and simulation software designed and tuned to give accurate and fast solutions in support of stockpile 

stewardship and nuclear deterrence. LLNL is fielding El Capitan in FY 2024, the first exascale system in support of national 

security, marking the culmination of a 15-year effort in DOE and DOE/NNSA to realize exascale computing. This deployment is 

backed by a nearly decade-long effort to develop and update codes and software for the exascale era and has been performed

in collaboration with vendor partners, other DOE/NNSA labs, and the broader community. LLNL HPC expertise includes 

application development, system software, and a rich supporting software stack of libraries and tools.

Challenges Strategies

LLNL must anticipate and adapt to the 

rapid pace of change taking place in the 

broader computing industry as 

hardware becomes increasingly 

specialized, and workloads increasingly 

move to the cloud. 

LLNL software applications must 

continue to support design and 

certification, while also continuously 

adapting to new hardware, software, 

and development practices.

Current Strategy Being Implemented Future Strategies Needed

LLNL is building on its exascale strategy to 

deploy accelerated architectures and develop 

future-proof applications based on 

modularity and abstractions that hide 

hardware complexity from the developer. As 

Artificial Intelligence and Machine Learning 

takes root in the computing ecosystem, LLNL 

is committed to exploring how to apply these 

techniques in a scientifically rigorous manner 

to allow even higher productivity, faster 

turnaround, and deeper insight into our 

mission-critical applications.

Leverage investments being made 

by industry in cloud computing to 

bring better technologies for 

managing LLNL IT environments. 

Benefits will include, but are not 

limited to, higher productivity for 

developers and users, the ability to 

more easily burst into public clouds 

on demand, and increased security 

in a multi-tenancy environment.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-9

High Energy Density Physics

LLNL designs and executes experiments to advance fundamental understanding of HED regimes, the state of matter a weapon is 

in when the majority of yield is produced. These experiments provide data that improves our fundamental understanding of 

how to advance and validate computational tools that underwrite the design and certification of the stockpile. HED 

experiments at the NIF produce data on high-Z material properties, burn physics, radiation transport, radiation hydrodynamics, 

and a variety of other topics.

Challenges Strategies

Experimental infrastructure is aging 

and is subject to increased usage and 

increased operational tempo. Although 

the United States has pioneered HED 

physics, nations around the world are 

advancing their own experimental 

capabilities that may soon be 

competitive with the previously unique 

capabilities of the United States.

Current Strategy Being Implemented Future Strategies Needed

LLNL has developed a long-term investment 

plan to sustain and improve infrastructure 

while supporting more than 400 shots per 

year at the NIF. Infrastructure 

recapitalization and modernization are 

essential to realizing this plan.

Develop an enduring infrastructure 

capability base in target fabrication 

and be prepared to manage 

increased facility usage.

Additive Manufacturing

To develop and mature responsive and resilient material and manufacturing options for system components, LLNL is driving 

advancements in manufacturing and component design optimization to rapidly create and qualify novel materials, structures, 

and advanced manufacturing methods through fundamental understanding of the underlying science and engineering, leading 

to improvement of these processes as well as invention and development of new processes. Additionally, providing rapid 

turnaround manufacturing capability for fast iteration with LLNL engineering and physics designers is critical to component 

development for emerging needs. These efforts extend, build on, and integrate foundational capabilities at LLNL for validated 

predictive simulations, tailored materials synthesis, characterization and testing, design optimization, precision engineering and 

metrology, machine learning and data science, and additive manufacturing. Success also requires integrating with performance 

testing capabilities – including exascale computing, hydrodynamic and explosive testing, high energy density testing platforms, 

and environmental testing facilities.

Challenges Strategies

LLNL manufacturing facilities and 

infrastructure are dispersed and aging. 

Maturation of additive and advanced 

manufacturing technologies requires 

collaboration between the design, 

engineering, materials, and 

manufacturing communities. 

Success also requires effective 

integration of capabilities in feedstocks, 

design, characterization and testing, 

environmental and dynamic materials 

testing, precision engineering and 

metrology, machine learning and data 

science, and predictive simulations and 

performance modeling.

Current Strategy Being Implemented Future Strategies Needed

Exploit industry/academic/laboratory 

collaborations at the Advanced 

Manufacturing Laboratory. Engage and 

partner with NNSA production agencies to 

accelerate mutual understanding of needs, 

tech transfer, and adoption through the 

manufacturing enclave model/concept.

Execute existing infrastructure investment 

plans, including exploiting capabilities in the 

Applied Materials Engineering facilities and 

the Polymer production enclave; completing 

renovations to the LLNL Manufacturing 

complex, Non-Destructive Evaluation 

facilities, and Mechanics of Materials 

facilities; completing the new NonDestructive Evaluation and manufacturing 

high bay facilities; and supporting completion 

and use of HE and energetic materials 

capabilities housed in the Energetic Materials 

Development Enclave.

Realize infrastructure investments 

to build on existing capabilities, 

including facilities that integrate 

new feedstocks and manufacturing 

processes with automated 

processes, in-situ characterization, 

and advanced data analytics 

approaches. Planned infrastructure 

includes the Stockpile Materials 

Development facilities and Product 

Realization Infrastructure for 

Stockpile Modernization facility.

Deepen the collaborative 

innovation approaches 

demonstrated in the Polymer 

Enclave by successfully launching 

additional collaborative 

collaboration Enclaves as they are 

identified and prioritized.

HE = high explosives

HED = high energy density

HPC = high performance computing

IT = information technology

LEP = life extension program

NIF = National Ignition Facility

RDT&E = research, development, test, and evaluation
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-10

F.2.1.4 Accomplishments

◼ On December 5, 2022, an experiment at the NIF achieved fusion ignition and energy gain. In the 

historic experiment, 2.05 megajoules (MJ) of laser energy produced 3.15 MJ of fusion energy.

◼ LLNL completed all deliverables for Cycle 27 of the Annual Assessment Review, including extensive 

peer review, as part of the Independent Nuclear Weapon Assessment Process. The Laboratory 

also met the requirements for sustaining the W80, B83, W84, and W87 systems.

◼ The W80-4 LEP is preparing to move into Phase 6.4. Programmatic activities in FY 2022 included 

execution of baseline design reviews, completion of multiple high-fidelity engineering tests, 

activities to improve producibility, and support of Air Force flight tests.

◼ In October 2021, the W87-1 Mod Program moved into Phase 6.2A; the Weapon Design and Cost 

Report was completed, preparing for entry into Phase 6.3; and activities focused on maturing 

weapon design options and modern manufacturing methods.

◼ The $100 million Exascale Computing Facility Modernization project was completed on schedule 

and under budget, preparing LLNL for delivery of NNSA’s first exascale supercomputer, El Capitan, 

in 2023.

◼ An LLNL research team developed a prototype chemistry-on-a-chip platform for field-deployable 

nuclear forensics after a nuclear incident. The tool requires only a microsample, yielding easy, 

safe analyses by scientists.

◼ In work for the DoD’s Defense Threat Reduction Agency, LLNL scientists and research partners 

made headway developing a multi-pathogen vaccine for protection of warfighters.

◼ LLNL scientists participated in NASA’s successful Double Asteroid Redirection Team experiment 

conducted on September 26, 2022—providing pre- and post-experiment high-performance 

simulations of the spacecraft’s collision with smaller of the two asteroids.

◼ LLNL scientists are pioneering CogSim—the use of artificial intelligence to expedite scientific 

discovery by merging simulations and experimental results, including CogSim’s award-winning 

application in support of NIF experiments.

F.2.1.5 Lawrence Livermore National Laboratory Workforce 

LLNL continues to comprise of primarily scientists, technicians, and engineers, who represent over 

75 percent of the FY 2022 workforce. LLNL new hires have increased representation of the early-career 

workforce in the laboratory population. LLNL continues to use campus career fairs and strategic evening 

with industry functions, national and local diversity recruiting, and discipline-specific national and local 

events, independently and as part of the National Security Enterprise 

Workforce Recruitment Strategy, to attract candidates. Partnerships 

with federally serving programs such as Science Undergraduate 

Laboratory Internships, Minority Serving Institutions, and several 

military collaborations have increased hiring for military students and 

vets, resulting in a 51 percent increase in veteran employees since 

FY 2019. In FY 2022, 49 percent of the LLNL workforce had 0–5 years of 

service. Additionally, LLNL leverages early enagement with potential 

employees through its student and internship programs.

Early Engagement in FY 2022

• Students: 668

• Interns: 65

• Post-doctorates: 432
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-11
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-12

LLNL is challenged by increasing attrition among employees with 0–5 years of service (Figure F–5). 

Retention programs, such as career development courses, education assistance programs, the Laboratory 

Directed R&D program, Federal details, and work-life balance programs continue to be used to improve 

retention. 

Figure F–5. LLNL separations by years of service

The advanced career population has maintained consistency, with 28 percent of employees being 

retirement-eligible, while the mid-career population has slightly increased, as Figure F–6 shows. Recent 

hiring combined with consistent numbers of retirements have led to increasing proportions of 

early-career participation (less than 35 years old) and mid-participation (35–40 years old) employees 

among the laboratory population. Separations continue to be a concern, however, as LLNL experienced 

its highest attrition year since FY 2013 (Figure F–7).
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-13

Figure F–6. LLNL workforce participation trends by age category and percent advanced career

Figure F–7. LLNL employee separation trends1

1 The peak in FY 2013 represents a laboratory budget reduction that resulted in a significant number of early retirements and 

some layoffs, which are defined as involuntary separations in the chart. Voluntary separations have increased every year since 

FY 2016, particularly in FY 2022. FY 2022 retention is discussed more broadly in Chapter 7.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-14

LLNL anticipates continued growth over the initial part of the Future Years Nuclear Security Program 

(FYNSP) period, especially as the work scope increases for W80-4 LEP and W87-1 Mod Program activities

(Figure F–8).

Figure F–8. LLNL workforce projection needs by Common Occupational Classification System
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-15

F.2.2 Los Alamos National Laboratory

F.2.2.1 Mission Overview

Los Alamos National Laboratory (LANL), initially known as Project Y, was organized in April 1943 during 

World War II for the design of nuclear weapons as part of the Manhattan Project. After nearly 80 years, 

LANL continues its service to the Nation through applications of scientific and engineering solutions to 

solve national and global security challenges. The laboratory relies on its skilled workforce, a complex 

portfolio of facilities (nuclear, HE, hazardous, multifunctional, and general purpose), specialized 

equipment, and disciplined business practices to meet its missions and deliver solutions. 

LANL’s Weapons Activities represent foundational elements of the DOE/NNSA Stockpile Stewardship and 

Management Plan (SSMP). LANL designed five of the seven types of nuclear warheads in the deployed 

stockpile and is currently responsible for the continued safety, security, and effectiveness of the B61 

gravity bomb, the W76 and W88 submarine-launched intercontinental ballistic missile warheads, and the 

W78 intercontinental ballistic missile warhead. LANL leads the B61-12 LEP and the W88 Alteration (Alt)

370 Program and is also a production agency with responsibilities including the manufacturing of pits, 

detonators, detonator cables and radioisotope thermoelectric generators (RTGs). LANL weapons 

programs provide design expertise, production expertise, and tools including advanced experimental

capabilities, modeling and simulation, processing, prototyping, production, surveillance, and testing of 

weapons materials, and components and warheads assemblies (without nuclear materials). 

LANL’s national security mission requires a multidisciplinary approach to solve some of the Nation’s 

toughest science and engineering challenges. In addition to direct stockpile stewardship activities, the 

laboratory addresses overcoming national security and economic challenges, including nuclear 

nonproliferation and counterterrorism, medicine and health sciences, energy, and advanced 

computation. LANL is also involved in strategic partnership and collaborations with other agencies.

Science, technology, and engineering capabilities consist of a diverse portfolio and execute laboratory 

missions through six scientific pillars. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-16

LANL’s leadership assembles a broad spectrum of operational expertise, resources, and processes to 

enable the readiness and excellence of the stockpile stewardship and science, technology, and 

engineering missions. These operational functions address LANL’s broad capabilities in integrated

planning and execution, safety, security, efficiency, accountability, waste, business practices, workforce 

management/development, and community relations and service. LANL has defined strategic objectives 

that align with national policy and DOE/NNSA strategies: (1) Nuclear Deterrent, (2) Threat Reduction, 

(3) Technical Leadership, and (4) Trustworthy Operations. The major cross-cutting challenge in meeting 

these objectives and critical outcomes is understanding and improving our operational capacity, including

meeting human capital needs with hiring, diversity, knowledge retention, and competitive compensation; 

revitalizing our infrastructure; and improving disciplined operations. Accomplishments for each pillar are 

highlighted below.

LANL’s Strategic Objectives align with NNSA Mission Priorities

LANL’s leadership assembles a broad spectrum of operational expertise, resources, and processes to 

enable the readiness and excellence of the stockpile stewardship and science, technology, and 

engineering missions. These operational functions address LANL’s broad capabilities in integration 

planning and execution, safety, security, efficiency, accountability, waste, business practices, workforce 

management/development, and community relations and service.

LANL operates a complex portfolio of nuclear, HE, and specialized facilities and physical infrastructure. 

Additional descriptions of laboratory assets and capabilities, and their current state are presented below.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-17

F.2.2.2 Funding

FY 2024 DOE request – site funding by source

(total LANL FY 2024 request = $4,922 million)

LANL split for the FY 2024 Weapons Activities

President’s Budget Request ($4,053 million)

F.2.2.3 Site Capabilities

LANL is the lead design agency for the B61, W76, W78, and W88 systems and 

is also the production agency for pits, detonators, detonator cables, and 

RTGs. LANL contributes to nuclear design and physics capabilities in the 

nuclear security enterprise and is the Nation's Plutonium Center of 

Excellence for Research and Development. Core competencies at LANL 

include weapons physics design and analysis; weapons engineering and 

energetics, design, analysis, testing, and integration; stockpile component 

production and surveillance for pits, detonators, and RTGs; HED physics; 

materials science and engineering; and HPC. 

LANL operates a complex set of nuclear, high explosives, and other 

specialized scientific facilities. Several weapons mission critical facilities 

include the Plutonium Facility (PF-4), the Dual-Axis Radiographic 

Hydrodynamic Test Facility (DARHT), the Uranium R&D facility (Sigma), the 

Metropolis Center’s Strategic Computing Complex, Waste Handling Facilities, 

as well as several other facilities within the National Energetic and 

Engineering Weapons Campus. LANL operates several flagship user facilities, 

including the DOE/NNSA Los Alamos Neutron Science Center (LANSCE), the 

DOE/Office of Science Center for Integrated Nanotechnologies (with SNL), and one of the sites of the 

National Science Foundation’s National High Magnetic Field Laboratory. 

LANL’s core capabilities and their associated challenges and strategies are described in Table F–2. 

Additional information on the plutonium capability, and LANL’s 30 pits per year (ppy) plan is presented.

A hydrodynamic experiment 

confinement vessel being inserted 

within the DARHT Weather 

Enclosure
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-18

Table F–2. Los Alamos National Laboratory capabilities

Weapon Component Production

LANL is responsible for producing and surveilling pits, RTGs, and detonators designed by LLNL, LANL, and SNL for use in the 

nuclear weapons stockpile. As the Nation’s Plutonium Center of Excellence, LANL also performs fundamental research and 

produces plutonium components and materials to support other NNSA and DOE missions.

Challenges Strategies

Increase pit production to a steady 

state rate of at least 30 ppy.

Current Strategy Being Implemented Future Strategies Needed

• Infrastructure investments: Through four 

major line-item projects and numerous 

smaller capital projects, install pit production 

process equipment and construct facilities for 

access, office space, parking, cafeterias, and 

training.

• Workforce: Recruit, hire, and train the 

workforce required to produce pits, operate 

and maintain facilities, and provide security.

• Continue to increase integration 

of construction and production 

activities that occur concurrently 

in an active plutonium facility.

• Improve hiring and retention 

efforts.

• Improve knowledge transfer from 

experienced subject matter 

experts to new workforce.

Weapons Physics Design and Analysis

LANL performs integrated experiments and simulations to enable design and assessment of the nuclear explosives package for 

both enduring and future weapons systems. Design and assessment capabilities encompass hydrodynamic and subcritical 

experiments; proton radiography, materials, and nuclear science experiments; HPC; HE RDT&E; weapons engineering, surety, 

radiography, and assembly; and accelerator technology. 

Challenges Strategies

Aging in weapons materials and 

components; an aging workforce with

specialized weapons knowledge and 

experiments capabilities, lack of 

programmatic needs to transition to 

the next generation of designers and 

engineers; and degrading design and 

certification infrastructure.

Current Strategy Being Implemented Future Strategies Needed

Current warhead modernization activities

provide a near-term opportunity to reinvest in 

current capabilities and exercise the workforce. 

LANL is coordinating with DOE/NNSA to address 

aging enduring physical infrastructure and 

modernize specialized capabilities such as 

DARHT, LANSCE, Sigma, HPC, HE, and weapons 

engineering facilities. 

• Continue coordination with 

DOE/NNSA. Several missioncritical facilities will need 

substantial reinvestment and/or 

replacement, with planning 

required in advance.

• See Chapter 7 for enterprise 

workforce strategies.

High Performance Computing

The HPC core capability provides the supercomputers, facilities, and computer science that enable simulations of weapons 

performance for all aspects of stockpile stewardship. HPC enables scientists to routinely use multi-dimensional simulations to 

increase understanding of complex physics, as well as improve confidence in the predictive capability for stockpile stewardship

for LEPs and significant finding investigations (SFIs). The ASC Program leverages the ATS and Commodity Technology System for 

this work.

Challenges Strategies

Near-term challenges, by 

approximately 2026, include physical 

infrastructure modernization to 

accommodate the next-generation 

supercomputer (ATS-5) at LANL. 

Current Strategy Being Implemented Future Strategies Needed

Planning is ongoing for the near- and long-term 

HPC infrastructure. Trinity (ATS-1) will be 

replaced by Crossroads. The EPCU line item is a 

key enabling infrastructure investment to meet 

power demand for the next-generation 

supercomputer.

Modernization of HPC with ATS-5 

system.

Weapons Engineering and Energetics

Weapons engineering and HE capabilities provide the materials, components, and assemblies for legacy and new life extension 

program work. The scope also covers modeling weapon performance, safety, engineering, and aging responses throughout their 

operating conditions and life cycle. This capability includes the experimental testing required to assess the current state of the 

stockpile; surveil the current stockpile and address SFIs; assess and qualify existing energetic materials; and develop novel

energetics for future designs. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-19

Challenges Strategies

The primary challenge is aging physical 

infrastructure. Many of the facilities 

were built in the 1950s and were 

optimized for the fabrication and 

engineering testing capabilities and 

processes of that time. 

Current Strategy Being Implemented Future Strategies Needed

• The current strategy includes a combination 

of line-item investments and minor 

construction to consolidate, replace, or 

extend the life of existing facilities.

• Once LANL has available construction 

capacity, construct the Energetic Materials 

Characterization line-item.

Strategies are being developed to 

address modernization needs for 

several mission critical facilities. This

effort includes continued 

coordination within LANL and with 

DOE/NNSA.

Hydrodynamic and Subcritical Experiments

Hydrodynamic and subcritical experimental capabilities supply data to weapon physicists and engineers to inform the annual 

assessment process and certification decisions, advance nuclear weapon science, refine weapon computational models, develop 

emergency response tools, assess foreign and terrorist designs, gauge technological surprise, and develop the skills and 

experience of weapon designers and engineers. 

Challenges Strategies

The hydrodynamic facilities and 

infrastructure (DARHT complex) are 

aging, and new 

diagnostics/experimental techniques

are needed. There are demands for 

additional facilities for DARHT-related 

maintenance, repair, and storage space 

for mission critical spares.

Current Strategy Being Implemented Future Strategies Needed

The ECSE program will deliver advanced 

diagnostics at the Nevada National Security Site 

in 2030. 

Execute plans for the DARHT 

Capability eXpansion Strategy.

Neutron Science – Los Alamos Neutron Science Center (LANSCE)

The protons and neutrons produced by the LANSCE accelerator deliver essential material science, nuclear physics, and dynamic 

radiography data needed for assessment of the current stockpile, qualification of advanced manufacturing techniques, 

certification of the future stockpile, and threat reduction. LANSCE data are used for materials characterization; support of LEP, 

Alt, and Mod certification; qualification of new materials; and the development of advanced material models predictive 

capabilities. 

Challenges Strategies

The LANSCE accelerator was 

commissioned in 1972, and some 

components are starting to experience 

end-of-life failures. Deferred 

maintenance has reduced the reliability 

of other components.

Current Strategy Being Implemented Future Strategies Needed

A modernization initiative, including the LAMP 

line-item, is being pursued. LAMP would 

replace obsolete elements at the front of the 

LANSCE accelerator and address performance 

limitations. Recapitalization investments are 

addressing aging facility condition issues. A new 

spallation target and the return of explosively 

driven plutonium experiments are targeted.

Next generation facilities, 

infrastructure, and equipment will 

eventually be required.

Uranium, Beryllium, Organics, and Inorganics

The Sigma Capability includes the expertise, facilities, and equipment for work with uranium, beryllium, and most organic and 

inorganic materials in the stockpile. Sigma maintains a small-lot production capability for all nuclear weapons package 

components and relevant materials (except HE, HEU, and plutonium). The work provides low- to mid-TRL manufacturing process 

development, pathfinding for new materials and emerging technologies, and understanding of the materials’ properties inclusive 

of performance and ageing behaviors. Additional capabilities include surveillance activity for legacy weapons systems, as well as 

manufacturing science and production support at Y-12 and KCNSC.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-20

Challenges Strategies

Built in the late 1950s, Sigma Complex 

facilities are increasingly expensive to 

operate and necessary investments in 

infrastructure offer diminishing return. 

The aging infrastructure, including 

mission critical equipment, face 

frequent downtime that introduce 

operational risk and negatively impacts 

Sigma’s ability to meet milestones, 

especially as demand increases.

Current Strategy Being Implemented Future Strategies Needed

Several revitalization efforts have been 

completed (such as the modernization of the 

Electrochemistry Lab and completion of the 

Machining Annex). Other significant upgrades 

to processing equipment are proposed within 

the next 5–10 years. Sigma will transition to 

Weapons Program operations in the near-term.

The Sigma Replacement project is 

aligned with enduring mission 

activities and emerging demands.

Alt = alteration

ASC = Advanced Simulation and Computing

ATS = Advanced Technology System

DARHT = Dual-Axis Radiographic Hydrodynamic Test

EPCU = Electrical Power Capacity Upgrade

GPP = General Plant Projects

HE = high explosives

HEU = highly enriched uranium

HPC = high performance computing

LAMP = LANSCE Modernization Project

LANSCE = Los Alamos Neutron Science Center

LEP = life extension program

Mod = modification

RDT&E = research, development, test, and evaluation

RTG = radioisotope thermoelectric generators

TRL = technology readiness level

Plutonium Capability and 30 ppy Plan – LANL is designated by NNSA as the Nation’s Plutonium Center of 

Excellence. The LANL plutonium enterprise includes an experienced and skilled workforce, high-hazard 

nuclear facilities with associated infrastructure, and unique plutonium processing, fabrication, and 

experimental capabilities. This enterprise enables the safe, secure, and compliant work with plutonium 

and other materials and components. The Nation relies on the LANL plutonium enterprise to perform the 

following plutonium missions:

◼ Produce plutonium pits for the nuclear weapons stockpile

◼ Produce RTGs for the nuclear weapons stockpile

◼ Produce plutonium-238 heat sources for use in space exploration

◼ Evaluate pits returned from the nuclear weapons stockpile to support annual stockpile 

assessments

◼ Produce plutonium components for assembly into devices for use in subcritical experiments

◼ Conduct fundamental science on the material properties and aging of plutonium 

◼ Process plutonium into forms suitable for disposition to support nuclear nonproliferation goals

◼ Evaluate containers for safe storage of plutonium materials throughout the DOE/NNSA complex

◼ Recover americium for the DOE Office of Science

In May 2018, NNSA directed LANL to increase pit production 

to deliver a minimum of 30 War Reserve pits per year starting 

in 2026. In June 2018, NNSA selected Triad National Security, 

LLC to manage LANL starting in November 2018. Recognizing 

the urgency to understand the actions and resources 

required to expand the pit production mission, LANL 

completed a thorough sitewide assessment of resources, 

such as facilities, workforce, capabilities, and business 

systems. The results of this assessment were published in 

2019 by LANL (with feedback from NNSA) in a series of plans 

related to pit production. In 2020 and 2021, these plans were 

updated and expanded to include requirements and planning 

LANL employees working in a downdraft room in the 

plutonium facility. The airflow in a downdraft room 

creates a safe environment required to perform 

certain types of work in pit production.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-21

for all plutonium missions. As a result of these planning efforts, NNSA recognized the need to increase 

the annual budget for the pit production mission at LANL, and Congress increased funding for pit 

production and the facilities, security, and services required to support the LANL plutonium enterprise.

In response to the surge in activity to expand pit production, LANL began routine 24/7 operations in the 

Plutonium Facility in FY 2022. Expanded operational hours enables LANL to deconflict schedules for 

programmatic, construction, and maintenance activities.

F.2.2.4 Accomplishments

LANL successfully met mission delivery in the following laboratory strategic areas: nuclear deterrence, 

threat reduction, technical leadership, and trustworthy operations.

◼ LANL completed 150 of 153 Defense Program milestones, achieving a 98 percent completion rate 

(including a Level 1 aging and lifetimes milestone). 

◼ LANL completed seven plutonium pit builds compared with five planned builds.

◼ LANL completed deliverables for the annual assessment reporting process.

◼ DARHT executed four hydrodynamic shots and three static series.

◼ LANL executed 80 experiments in support of the evolving stockpile and more than 400 dynamic 

materials and nuclear physics experiments.

◼ LANL continued leadership role for the W93-0 and achieved written authorization for Phase 2.

◼ LANL modernized technology for the radiation case, including remarkable progress on direct 

casting of binary components.

◼ LANL developed new HE formulations as alternatives for potential insertion into emerging 

weapons programs. 

◼ LANL shipped more than 6,900 cubic meters of waste and prevented a backlog of generated 

waste.

◼ LANL delivered the first phase of the Crossroads supercomputer in FY 2023, and Crossroads 

deployment is being finalized in FY 2024. LANL completed an electrical system upgrade and 

98 percent of water-cooling loops for CTS-2 and Crossroads.

◼ LANL refurbished over 1 million square feet of office space, replaced 4.8 acres of roof, and laid 

over 9.5 acres of pavement. LANL occupied a second Santa Fe lease to provide a centrally located 

workspace. 

◼ LANL invested in a new and expanded employee benefits program (effective as of January 2023), 

which includes paid time off, enhanced maternity and parental leave, compassionate care, and 

accelerated employer match for 401(k), among other changes. 

◼ LANL’s personnel security has accelerated clearance processing through several improvements. 

F.2.2.5 Los Alamos National Laboratory Workforce

In FY 2022, LANL’s diverse workforce was comprised of 11,275 regular, 

limited term, and protective force employees with expertise across 

various disciplines working to solve national security challenges. This 

population of employees had an average age of 44 years and an average

of 9.7 years of service. Approximately 36 percent of LANL’s employees 

were eligible to retire.1Staffing plans indicate that hiring is expected to accommodate the workforce 

1 Retirement Eligible is age 50+.

Early Engagement in FY 2022

• Students: 2,091

• Post-doctorates: 647
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-22

growth needed to meet future mission demands (e.g., pit production) and anticipated attrition over the 

next 5 years. Additionally, LANL offered internships and other student engagement opportunities to 

nearly 2,100 students during FY 2022 and hosted an additional 647 post-doctoral research fellows.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-23

LANL’s FY 2022 employee headcount increased 8.2 percent from FY 2021. Growth was seen in most 

categories, with the largest increases observed for general management (+18.5 percent), engineers 

(+11.8 percent), and professional administration (+8.0 percent).2 The general management increase was 

attributed to the recategorization of technical managers in pit mission areas (establishing a lower ratio of 

manager to employee) to improve safety and efficiency. The workforce will continue to increase by 

approximately 1,000 additional full-time equivalent over the next few years, as growth will be targeted to 

support plutonium programs and dependent infrastructure investments.

There is an even distribution of employees across the specified 5-year age groups, as shown in 

Figure F–9. The median age dropped from 45.1 (FY 2021) to 43.6 (FY 2022), reflecting the increasing 

population of younger new hires. The retirement eligible population has also decreased from previous 

years.

Figure F–9. LANL separations by years of service

The increase in early career hires and retirements has impacted headcount by years of service, shown in 

Figure F–10. The group of employees with 5 or less years of service or less has increased from 43 percent

(FY 2020) to 51 percent in FY 2022. This trend is expected to continue, with ~9,000 employees (regular 

appointment type) expected to have 5 or less years of service or less by FY 2028. The average years of 

service was 9.7 in FY 2022, down from 10.9 (FY 2021) and 11.4 (FY 2020).

2

In FY 2022, LANL began including Limited Term (242) and Protective Force (423) employees in the employee site count. 

Protective Force employees are counted under the COCS code of “Other.” Protective Force employees are contractors, thus LANL

has limited age and years of service information; therefore, they are not included in the other demographic charts. LANL also 

does not classify any employee under the COCS code of “Laborers.”
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-24

Figure F–10. LANL workforce trends by career category and percent advanced career

Retirements and voluntary separations have increased in FY 2022; the most separations were seen in 

employees with 10 years of service or less (74 percent of all voluntary attrition), shown in Figure F–11. In 

addition to retention challenges, such as the competitive job market and limited housing and supporting 

services (e.g., daycare, schooling, medical care, etc.), the separation increase may have been compounded 

by employees delaying planned separation from FY 2020 into FY 2022.

LANL has been hiring in all career categories, but the largest portion of hiring is among early career 

employees (51.3 percent in FY 2022). The population of early career employees continues to grow in 

FY 2022 (up 27.2 percent); it has more than quadrupled over the past decade (shown in Figure F–10). This 

increase is due to early career employees making up most of the new hires. Mid-career employees 

experienced an increase of 11.3 percent, which is due to onboarding of mid-career new hires and the

transition of previous new hires from the early career stage into mid-career. Inversely, the population of 

advanced career employees has decreased over the past few years.

Figure F–12 shows that total separations (1,147 in FY 2022) from the laboratory are again higher than the 

previous fiscal year (757 in FY 2021), reinforcing the retention challenge. Both retirements (+18 percent) 

and voluntary separations (+75 percent) increased. As noted above, retention challenges due to the 

competitive job market and limited housing and supportive services could have contributed to the 

separation increases observed. LANL is addressing these challenges via recruitment, hiring, total 

compensation and benefit changes, diversity, equity, inclusion, and accessibility approaches, training, and 

knowledge retention approaches.

The LANL workforce is projected to grow over the FYNSP period, as shown in Figure F–12, to meet the pit 

production rate capacity requirements, scope increases in weapons work, infrastructure modernization 

plans, and enduring scientific and national security missions. The need for retention efforts is expected to 

remain high due to competitive job markets in engineering, technology, and craft areas. The laboratory is 

making significant investments in programmatic and enabling physical infrastructure and in processes to 

meet increasing demands for office space, parking, training, housing, and other support services.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-25

Figure F–11. LANL employee separation trends

Figure F–12. LANL workforce projection needs by Common Occupational Classification System3

3 The increase in headcount projections is attributable to the LANL pit production mission. Technician and Professional

Administration categories are expected to be required and, thus, grow in the next years.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-26

F.2.3 Sandia National Laboratories

F.2.3.1 Mission Overview

Sandia National Laboratories (SNL) is a DOE/NNSA multi-mission Federally Funded Research and 

Development Center (FFRDC). Since 2017, SNL has been managed and operated by National Technology 

and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., with 

primary locations in Albuquerque, New Mexico, and Livermore, California. As an FFRDC, SNL operates in 

the public interest with objectivity and independence, free from organizational conflicts of interest, by 

maintaining core science, technology, and engineering capabilities to address missions of national 

significance.

For over 70 years, SNL has delivered essential and innovative engineering, science, and technology to 

resolve the Nation’s most challenging security issues. SNL began in 1945 as Z Division, the ordnance 

design, testing, and assembly arm of Project Y, which after World War II became Los Alamos Scientific 

Laboratory. Z Division was renamed Sandia Laboratory in 1948 and, in 1949, Sandia Corporation was 

established as an AT&T, Inc. subsidiary to manage the laboratory through a no-fee contract. In 1956, a 

second site was opened in California’s Livermore Valley. In 1979, Congress designated Sandia Laboratory 

as a DOE national laboratory. SNL has other sites, including Tonopah Test Range, Nevada; Kauai Test 

Facility, Hawaii; Washington, DC; Weapon Evaluation Test Laboratory, Texas; and Minnesota Site, 

Minnesota. 

The nuclear deterrence mission exists at SNL within a framework of five interdependent portfolios that 

represent multiple missions. Most of these have a direct and symbiotic relationship with nuclear weapons 

work, and all strengthen SNL’s capability-based science and engineering foundation.

SNL’s activities for other Federal agencies and for non-Federal entities leverage, sustain, and strengthen 

the unique capabilities, facilities, and essential skills that support the Office of Defense Programs mission 

and broader national security needs. SNL’s national security work includes the following programs’ 

portfolios:

◼ Nuclear Deterrence

◼ Global Security
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-27

◼ National Security Programs

◼ Energy and Homeland Security

◼ Advanced Science and Technology 

SNL’s five program portfolios set strategic direction 

for their respective mission spaces and have 

identified multi-year program priorities that align to 

and support NNSA mission priorities. Functional 

areas including facilities, human resources, 

information technology (IT), finance and others 

develop and execute on strategic plans that ensure 

SNL has the resources and infrastructure to deliver 

on priority objectives.

SNL’s nuclear deterrence mission includes nuclear 

weapons R&D, design, qualification, testing,

certification, and systems integration of all 

components, subsystems, and systems, to arm, fuze, 

and fire a weapon to military specifications and 

ensure safety and security. The integration role is evident in three key areas:

◼ Integration of all non-nuclear components, systems, and subsystems

◼ Integration between a weapon’s non-nuclear portion and its nuclear explosives package

◼ Integration of a weapon with its military delivery platform

The current warhead modernization activities constitute SNL’s largest, most complex design, 

development, and qualification work scope in the last 30 years. SNL is involved in all stockpile 

modernization programs currently underway (the B61-12 LEP, W88 Alteration [Alt] 370 Program, W80-4 

LEP, W87-1 Mod Program, W93, and Mk21 Fuze), and is responsible for designing the life extension of the 

Safeguards Transporter and its replacement design (the Mobile Guardian Transporter [MGT]) to securely

transport nuclear weapon materials and components to DOE/NNSA partner sites and DoD customer sites. 

SNL also has production agency responsibilities for weapon non-nuclear components (e.g., power sources, 

neutron generators, and trusted, strategic radiation-hardened microelectronics).

As reinforced by the 2022 Nuclear Posture Review and recent global events, SNL’s nuclear deterrence

mission is now more urgent than at any time since the end of the Cold War. The United States must 

maintain the range of flexible, responsive, and tailored nuclear capabilities to protect ourselves and our 

allies against nuclear and non-nuclear aggression. This capability versatility translates to a need to sustain 

SNL’s capability-based science and engineering foundation to prepare for uncertain and evolving future 

threats. As an FFRDC, part of this service to the Nation is to scan the horizon for emerging national security 

issues and articulate the challenges anticipated for the country.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-28

F.2.3.2 Funding

FY 2024 DOE request – site funding by source

(total SNL FY 2024 request = $3,188 million)

SNL split for the FY 2024 Weapons Activities

President’s Budget Request ($2,681 million)

F.2.3.3 Site Capabilities

Table F–3. Sandia National Laboratories capabilities

Weapon Engineering Design, Analysis, and Integration/

Weapon Component and System Surveillance and Assessment/Agile Component and Systems Design

Systems integration, engineering, and surveillance are the core capabilities of SNL’s nuclear deterrence mission. SNL designs, 

develops, qualifies, and assesses arming, fuzing, and firing systems, neutron generators, gas transfer systems, power sources, 

energetic components, and weapon surety and nuclear safety and security systems for Alts, Mods, and LEPs. This capability also 

includes production responsibility for several non-nuclear components and robust prototyping that is enabled by model-based 

design and advanced manufacturing technologies. SNL performs surveillance evaluations and stockpile maintenance to assess 

nuclear weapon systems and detect or anticipate potential problems.

Challenges Strategies

SNL depends on viable infrastructure 

to execute its core mission now and in

the future, and to ensure that its 

premier workforce has the tools 

needed to execute the mission. SNL 

must maintain R&D, production, and 

surveillance capabilities.

Current Strategy Being Implemented Future Strategies Needed

• Proactively engage with NNSA to ensure an integrated 

approach to resolve facility challenges (co-locates 

related capability assets to improve efficiency and 

effectiveness, recapitalizes aging and inadequate 

facilities, and maintains facilities fit for mission use). 

• Execute the Power Sources Capability line item which 

entered the CD-1 phase in January 2023.

• Use SNL’s LIIST process to capture infrastructure needs

and define priorities. 

• Continue to pursue lineitem funding for key mission 

needs. 

• Recapitalization or 

replacement of equipment 

and facilities will be needed 

to sustain long-term health.

Given rapid geopolitical change, SNL 

must respond quickly to new threats 

while improving efficiencies as 

responsible stewards of national 

investments. Traditional weapon 

product lifecycles (design, 

development, and production) are too 

long, impeding the ability to respond 

in a timely manner to emerging 

threats. 

• Accelerate product realization through continued 

implementation of digital engineering tools and 

processes, updated peer review processes, modular 

architectures, and expanded partnerships across the 

nuclear security enterprise. 

• Continue the use of Technology Maturation Roadmaps 

to realize the benefits of new capability investments.

• Leverage rapid hardware procurement and 

prototyping to close knowledge gaps early.

Continue coordination with 

DOE/NNSA to define longerterm strategies and 

investments.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-29

Increasing supply chain risk to meet 

stringent non-nuclear component 

production requirements.

Seek opportunities to maintain current and develop new 

trusted supplier partnerships. Improve our sourcing 

methods to engage suppliers more strategically.

Continue current efforts and 

assess opportunities for new 

technologies.

Retention and recruitment of staff. 

Competition is high for the critically

skilled workforce required to maintain 

these capabilities, particularly 

electrical engineers, and computer 

scientists.

• Utilize university partnerships engagement strategies 

to work with academic partners to build collaborative 

research opportunities and fill SNL’s talent pipeline.

• Leverage the existing recruiting programs and initiate 

innovative on-campus research partnership, 

internships, and other creative mechanisms to develop 

a pipeline of future-generation warhead engineers.

• Use targeted recruiting programs that have been 

initiated to fill critical skills disciplines.

• NNSA and SNL are co-leading the NNSA Strategic 

Outlook Initiative study focused on the “Future of 

Work” to help combat workforce challenges.

• SNL added recruiters dedicated to its nuclear 

deterrence mission and is working with NNSA to 

enhance compensation and benefits. 

Continue to proactively engage 

with NNSA to ensure an 

integrated approach is used for 

competitive compensation and 

benefits.

Major life extension activities have 

focused laboratory attention and 

resources on near-term deliveries, 

making maturation of new 

technologies and components difficult. 

Seek opportunities to advance technology development 

in a broad range of program venues, including the 

NNSA’s Technology Maturation efforts, Strategic 

Partnership Projects, Laboratory-Directed Research and 

Development, and other NNSA programs such as the 

Stockpile Responsiveness Program.

Continue coordination with 

DOE/NNSA to define longerterm strategies and 

investments.

Radiation-Hardened Microelectronics Design and Manufacturing

Trusted, strategic, radiation-hardened advanced microsystems (i.e., nanoscale and microscale system security testing and 

evaluation).

Challenges Strategies

Trusted microsystems fabrication 

facilities are aging, past their design 

lives, and are required to support this 

capability.

Current Strategy Being Implemented Future Strategies Needed

Continue to work with NNSA to extend the life of current 

infrastructure needed to maintain the R&D capability 

and the production capability. Ensure an uninterrupted 

ability to produce trusted, strategic radiation-hardened 

microsystems. 

Work with NNSA to secure lineitem and other infrastructure 

funding for facilities and 

equipment needed to maintain 

this capability.

Materials Science and Engineering / Advanced Manufacturing

Virtually all classes of non-nuclear materials, including metals, polymers, glasses, ceramics, and electronic and optical materials and

their interfaces and interactions with their environments, are critical to the safety, security, and effectiveness of the U.S. nuclear 

weapon stockpile. This capability at SNL includes (1) evaluation of materials for aging, compatibility, and model validation to 

resolve stockpile and production issues rapidly and (2) innovation to replace legacy materials and evaluate new materials for 

insertion into the stockpile. 

Challenges Strategies

SNL must support evaluating materials 

aging, compatibility, and model 

development/validation and sustain 

the innovation necessary to replace 

legacy materials and evaluate new 

materials for insertion into the 

stockpile. SNL must advance material 

science R&D for response to evolving 

threats and future needs. 

Current Strategy Being Implemented Future Strategies Needed

SNL is creating new measurement and analytical 

capabilities to conduct R&D to enhance our 

understanding of the structure and processing of 

materials to evaluate their behavior, capturing the 

phenomenology driving this behavior, defining and 

predicting performance in current and future stockpiles, 

and enabling applications in additive manufacturing with 

a science basis for qualification.

Expand/continue engagement 

with DOE/NNSA.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-30

The material science and engineering 

facility at SNL/California does not 

meet modern seismic and other 

building code standards. The existing 

building (C916) was built in 1958. 

SNL/New Mexico material science and 

engineering facilities need 

revitalization since they are at the end 

of their design life and need extension 

of systems and new capabilities.

• Proactively engage with DOE/NNSA to ensure an 

integrated approach to resolving facility challenges.

• Use SNL’s LIIST process to capture infrastructure needs 

and define priorities. Commission studies to establish 

conditions and alternatives to best mitigate risk to the 

mission.

Continue coordination with 

DOE/NNSA. Continue to 

pursue Weapons Engineering 

Science and Technology 

Laboratory at SNL/California to 

ensure that modern and worldclass materials science 

capabilities lead to 

breakthrough solutions in 

response to enduring and

emerging national security 

challenges.

The current generation of materials 

scientists is approaching the end of 

their careers. The number of students 

seeking advanced degrees in material 

disciplines who choose to enter and 

work within the nuclear security 

enterprise may not be sufficient to 

meet future workforce needs. 

Competition is high for scientists and 

engineers who are qualified in these 

disciplines.

Leverage existing recruiting programs and initiate 

innovative on-campus research partnerships, internships, 

and other creative mechanisms to develop a pipeline of a 

future generation of materials science specialists for 

SNL’s unique needs. 

Reference Chapter 7 for 

enterprise recruitment and 

hiring challenges and 

strategies.

Environmental Effects Analysis, Testing, and Engineering Sciences/High Energy Density Physics/Advanced Experimental 

Diagnostics and Sensors

These capabilities include evaluation of the effects of operational and abnormal environments on nuclear weapon systems and 

components using an array of engineering science test equipment (e.g., the Annular Core Research Reactor, Z, Saturn, and 

HERMES), diagnostic tools, and techniques, as well as research and testing to support design, qualification, and surveillance.

Challenges Strategies

The workload imposed by concurrent 

LEPs is stressing the capacity and 

capability of aging facilities and 

equipment and accelerating 

replacement needs. Experimental test 

capabilities to validate data models 

require more and higher-fidelity data 

to enable stronger coupling with 

integrated design codes.

Current Strategy Being Implemented Future Strategies Needed

• Prioritize facility and equipment investments to ensure 

continuity of the engineering sciences capabilities. 

• Support enhancement of the predictive capability by 

tightening the coupling and integration of modelers 

and the data necessary for model validation. 

• Advance diagnostic capabilities to capture higherfidelity experimental data.

• Research and technology 

from current strategies and 

efforts will be applied to 

next -generation pulsed 

power and accelerator 

facilities (NGPP and CREST)

• Continue to sustain 

infrastructure investments 

that advance diagnostic 

capabilities to capture 

higher-fidelity experimental 

data and ensure confidence 

in the nuclear stockpile. 

These investments would 

include SNL’s Major 

Environmental Test 

Facilities.

NGPP experimental capabilities are 

needed to ensure models that validate 

safe, secure, and reliable performance 

of the Nation’s weapons.

Work with NNSA and the other design laboratories to 

establish the mission need and program requirements 

for a NGPP capability.

The ACRR delivers high-power, short 

bursts of neutron and combined 

neutron-gamma spectra to qualify 

designs under extreme combined 

radiation environments. The facility 

housing the reactor is older than 50 

years and predates modern nuclear 

safety standards.

• Develop an Extended Life Plan to address near term 

facilities and infrastructure needs to sustain ACRR.

• Mature CREST as a long-term replacement for ACRR.

Radiation effects and high energy 

density sciences facilities are aging 

and require significant sustainment 

activities to maintain capability for 

stockpile assessments.

Execute Saturn refurbishment project and work with 

NNSA to support the Z Sustainment Plan.

Continue to partner with NNSA 

on long-term infrastructure 

needs (including CREST and 

NGPP).
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-31

Competition is high for certain 

specialists in radiation effects science.

• Develop a pipeline of scientific and engineering 

expertise in radiation effects via current campus and 

diversity recruiting programs and initiate targeted, 

innovative on-campus partnerships, internships, and 

fellowships to secure highly talented graduates.

• SNL is working with NNSA to enhance compensation 

and benefits. 

See Chapter 7 for enterprise 

recruitment and hiring 

challenges and strategies.

High Performance Computing / Simulation Codes and Models

These capabilities include modeling and simulation capabilities of physical phenomena.

Challenges Strategies

Enhance the predictive capabilities of 

IDCs to support design, development, 

qualification, and assessments of nonnuclear components and systems for 

normal, abnormal, and hostile

environments. 

Current Strategy Being Implemented Future Strategies Needed

• Continue to accelerate digital engineering to shorten 

design cycles, support weapon qualification via 

credible simulations and increase agility in responding 

to changed product needs. 

• Participate in the DOE Exascale Computing Initiative; 

design and conduct experiments to support validation 

of IDCs that increase understanding of the physical 

phenomena and close the gap between models and 

the physical world. 

• Exascale computing 

platforms, machine learning 

techniques, new algorithms 

and quantum solutions will 

help us discover new 

solutions to complex 

problems focusing on 

weapon response in 

combined environments. 

• HPC platforms will be made 

more available and efficient 

by improving power 

reliability through local, 

renewable generation and, 

when appropriate, by 

obtaining cycles from 

commercial cloud providers.

Competition for high-demand 

disciplines, such as computational 

modeling with an emphasis on 

engineering analysis, makes recruiting, 

training, and retaining technical staff 

increasingly challenging.

• Leverage campus and diversity recruiting programs to 

develop a pipeline of future-generation HPC scientists 

and engineers.

• SNL is working with NNSA to enhance compensation 

and benefits. 

Training and sustaining a 

skilled, diverse workforce that 

thinks critically can quantify 

risk and incorporate innovative 

solutions with science-based 

confidence—a long-term 

strategy that transcends 

quarter-century planning.

ACRR = Annular Core Research Reactor

Alt = Alteration

CD = Critical Decision

CREST = Combined Radiation Effects for Survivability Testing

HERMES = High-Energy Radiation Megavolt Electron Source

HPC = high performance computing

LEP = life extension program

LIIST = Line-Item Investment Strategy & Timing 

Mod = Modification

NGPP = Next Generation Pulse Power facility

Z = Z pulsed power facility

F.2.3.4 Accomplishments

Directed Stockpile Work/Weapon Engineering and Production Focus

◼ B61-12 and the W88 Alt 370 progress: SNL, in partnership with the nuclear security enterprise, 

successfully achieved the first production units for the B61-12 and W88 Alt 370 in 2021. SNL 

continues to support the B61-12 and the W88 Alt 370.

◼ W80-4: SNL, in partnership with the nuclear security enterprise, met critical W80-4 program 

deliverables, completing tests needed to support the System Baseline Design Review.

◼ Stockpile Systems: SNL completed all testing and analysis for each system in the national stockpile 

resulting in the Laboratories Director’s Annual Assessment Letter. Improved modeling/simulation 

capabilities developed through the Advanced Scientific Computing portfolio were utilized.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-32

◼ W87-1 Weapon Development Cost Report (WDCR): SNL, in partnership with the nuclear security 

enterprise, submitted the SNL portion of the W87-1 WDCR. SNL ensured that fundamental 

changes critical to future weapons systems such as model based design and cybersecurity were 

included in the baseline. 

◼ W93 Phase 1: SNL, in partnership with Lockheed Martin and LANL, completed the W93 Phase 1 

report that detailed system concept, resulting in the first Phase 2 authorization in over 40 years.

◼ Production Agency (PA) success: In SNL’s PA role, SNL delivered over 50,300 non-nuclear parts, 

components, and technologies. These deliverables include neutron generators, power sources, 

explosive components and energetic materials, surety technologies and strategic, radiationhardened microelectronics.

◼ Mobile Guardian Transport (MGT): SNL completed a coast-to-coast 4,500-mile road trip with the 

MGT Preproduction Unit Prototype 2 trailer, visiting many DOE and DoD sites, to advance complex 

integration objectives and demonstrate Enhanced Cargo Restrain Operations.

RDT&E/Weapon Science and Technology Focus

◼ Delivering foundational science and engineering capabilities: The Advanced Certification and 

Qualification Program developed a test platform that enables the recovery of material samples 

after exposure to thermomechanical shock on Z. The platform establishes a new experimental 

capability at Z, and SNL executed two consecutive Z experiments in partnership with LANL to 

compare the compressibility of new and aged Pu. 

◼ Implementation of 8-inch Wafers at Microsystems Engineering Science and Application (MESA): 

MESA’s Silicon Microfabrication demonstrated production of Complementary Metal-Oxide 

Semiconductor 7 technology on 8-inch wafers, which required upgrading or replacing every tool 

and redeveloping more than 500 Complementary Metal-Oxide Semiconductor 7 process and 

measurement recipes. 

◼ Distributed Bus-Based Architecture (DBBA): SNL’s Foundation Bus team analyzed radiation test 

results that highlight the DBBA Foundation Bus and Power Bus robustness to stockpile-to-target 

sequence requirements. SNL developed definitions and options for a secure foundation bus 

architectures and dependencies on microelectronics technologies.

Attract, Retain, and Develop Talent

◼ Jill Hruby Fellowship: Established in 2019, the fellowship honors SNL’s former Director, Jill Hruby,

who was NNSA’s first female Laboratory Director, to develop women in engineering and science 

fields who are interested in technical leadership careers in national security. Two additional 

Hruby fellows were selected in FY 2022. 

◼ Weapons Engineering Professional Development: SNL internal activities assure the nuclear 

weapons enterprise workforce has the requisite technical knowledge. This is accomplished 

through a series of activities, including four exemplary programs: 

1. Nuclear Weapons Management Orientation Course: Provides managers an accelerated 

introduction to the nuclear deterrence program with a focus on SNL’s engineering role within 

the enterprise.

2. Weapon Intern Program (WIP): Since 1998, SNL has sponsored the WIP to benefit the nuclear 

security enterprise to accelerate training technical professionals in nuclear weapon 

development. 

3. Knowledge Development Program: The Nuclear Deterrence Knowledge Development 

Program is a system of tools, trainings and readings pertaining to the weapons lifecycle. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-33

4. Nuclear Weapons Legacy Program: The Legacy Hardware Program provides historical

knowledge for everyday use by collecting and facilitating access to classified nuclear weapons 

related legacy hardware.

◼ Laboratory Directed Research and Development Program: In 1992, Congress authorized national 

laboratories to initiate Laboratory Directed R&D to encourage creative research and development 

in areas of national security, particularly in high-risk, potentially high-payoff activities that enable 

national security missions and advance the frontiers of science and engineering.

◼ Academic Programs umbrella: The Academic Programs umbrella encompasses SNL University 

Partnerships Network, the Faculty Loan Program for Joint Appointments, and the Postdoctoral 

Research Program Office. The largest branch of Academic Programs is the SNL University 

Partnerships Network, which establishes and cultivates strategic academic partnerships that are 

mutually beneficial. 

Awards and Recognition

◼ Inventions/patents: During FY 2021 and FY 2022, SNL submitted a combined 588 invention 

disclosures, filed 462 patent applications, and received 237 granted patents. 

◼ Awards: In FY 2022, SNL researchers captured four R&D 100 Awards and supported a fifth award 

with Idaho National Laboratory, Pacific Northwest National Laboratory, and Johns Hopkins 

University Applied Physics Laboratory. Additionally, the Proactive Intrusion Detection and 

Mitigation System also won the R&D 100’s Special Recognition Market Disrupter Silver Award. In 

FY 2021, SNL received two Lawrence Awards and seven R&D 100 Awards (one in conjunction with 

the National Renewable Energy Laboratory), as well as two special awards for green technology 

and corporate responsibility. 

◼ SNL received the 2021 Diversity Team Award from Profiles in Diversity Journal, which recognized 

SNL as one of 14 of the world’s leading companies that take diversity and inclusion to a new level. 

◼ In 2022, SNL received the Honoring Investments in Recruiting and Employing American Military 

Veterans Act Medallion Award, recognizing successful recruiting, hiring, and retaining of veterans. 

Infrastructure Investments

◼ Power Sources Capability: In December 2022, DOE/NNSA selected SNL/New Mexico as the 

preferred alternative location for Power Sources Capability, which consolidates the capabilities 

across the SNL/New Mexico campus.

◼ Combined Radiation Effects for Survivability Testing (CREST): SNL with NNSA has continued to 

make progress to replace the Annular Core Research Reactor, an aging facility past its useful life, 

with CREST.

F.2.3.5 SNL Workforce

As of September 30, 2022, SNL has a headcount of 14,163 employees.

1

 

Additionally, SNL had 1,792 students and 467 post-docs on-roll 

throughout FY 2022. The average age of SNL’s workforce is 

approximately 44 years, and 17 percent of the population is eligible for 

retirement. The average years of service is 9.7, and the population is 

heavily concentrated among those with 1–15 years of service. Currently, 78 percent of employees have 

15 or less years of service, which reflects the hiring of 6,031 hires including both regular and limited-term 

1 Beginning FY 2022, all current year figures will include regular and limited term employees. Prior years’ data does not include 

limited term employees.

Early Engagement in FY 2022

Students: 1,791

Post-doctorates: 467
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-34

employees over the past 5 years. Within SNL’s workforce, 52.5 percent of the workforce have advanced 

degrees, of which 16.3 percent have PhDs and 36.2 percent have master’s degrees.

From the figures below, the data illustrates a relatively even age distribution for the workforce, with the 

years of service clustered between 0 and 15 years. Each age group brings a unique skillset to SNL, creating 

a balanced workforce. The mix of both experienced and new college graduates assure that the necessary 

skills and capabilities are present to support SNL’s mission work. A substantial percentage of employees 

are in earlier phases of their careers to replace those in later career phases, requiring an increased focus 

on knowledge transfer and training programs. Forty-six percent of employees have 5 or less years of 

service and 78 percent of employees have 15 or less years of service.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-35

Figure F–13 illustrates separations by years of service, with most separations occurring due to retirements 

for employees with higher years of service and voluntary separation of employees with less than 10 years 

of experience. Most separations involve retirements among those 51 years of age or older and voluntary 

separations for early career age groups. High numbers of retirements are reflected in the age groups 

between 56 and 65 years of age, which represents 79.6 percent of retiring employees. Retirements were 

higher among those with 21–45 years of service, while a significant number of voluntary separations 

occurred among those with 0–5 years of service. Specifically, of the voluntary employee separations, 

62.3 percent had 5 or less years of service, 91.4 percent for 10 or fewer years of service, and 97.3 percent 

had 15 or less years of service. This attrition may reflect the external demand for technical skills in a highly 

competitive market where SNL competes for talent. These workforce separations place increased 

importance on a relevant and acknowledged employee value proposition to draw talent from the external 

market as well as efficient and effective support processes, such as clearance process timeframes to get 

talent on mission work quickly. Another part of the solution to get talent started more quickly is internal 

training and knowledge transfer programs to enable new staff to engage and contribute on mission work. 

This separation population includes regular and limited term employees. 

Figure F–13. SNL separations by years of service
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-36

Figure F–14 shows SNL’s total workforce broken down by career stage defined by age groups. The trend 

line for the Advanced Career age group (employees over 51 years) is calculated as a percentage and is 

relative to the increase of workforce population.

Figure F–14. SNL workforce participation trends by age career stage and

percent advanced career

Figure F–15 provides SNL’s retirement data from 2012 through 2022. The number of retirements were 

higher in FY 2011 and FY 2012 because of announced pending changes in retiree benefits, which 

prompted some employees to initiate retirement. The surge in retirement in FY 2011 and FY 2012 

resulted in reduced retirements in FY 2013 and FY 2014. In FY 2015 through FY 2018, SNL returned to 

historical retirement rates. Total separations in FY 2021 increased as compared to the historical average. 

In FY 2022, both retirements and voluntary separations increased resulting from the pandemic; 

additionally, retirements increased potentially due to future retirement benefits changes and voluntary 

separations largely increased due to changes in the external job market. 

Figure F–16 provides SNL’s workforce outyear projection needs from 2024 through 2028.

Workforce is not only a function of workload but of retirements, separations, and internal movements as 

well. With SNL’s current understanding of the FYNSP and resulting workload, SNL will monitor workload 

fluctuations and manage the stability of the workforce through leveraging Strategic Partnership Projects, 

temporary staffing options, cross-training within programs, and strategic hiring.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-37

Figure F–15. SNL employee separation trends

Figure F–16. SNL workforce projection needs by Common Occupational Classification System
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-38

F.3 Nuclear Weapons Production Facilities

F.3.1 Kansas City National Security Campus

F.3.1.1 Mission Overview

For over 70 years, the Kansas City National Security Campus (KCNSC) has supported national security 

objectives by providing exceptional solutions, managed operations, and targeted services through its

diverse, inclusive, and talented workforce. Located in Kansas City, Missouri; Overland Park, Kansas; and 

Albuquerque, New Mexico, KCNSC is a trusted partner of NNSA and has earned a valued reputation of 

applying commercial best standards and driving innovations in engineering, manufacturing, and sourcing 

to fulfill its core mission supporting the safety, security, and reliability of the Nation’s nuclear deterrent.

KCNSC provides essential weapons modernization production, supply chain management, production 

science and stockpile stewardship for the strategic deterrent, secure transportation systems, and support 

to other government agencies. These efforts include unclassified and classified product realization, 

external sourcing, receiving and inspection, environmental testing, long-term stockpile storage, and a 

wide range of support services. KCNSC manufactures or procures over 80 percent of non-nuclear 

components for the nuclear stockpile and emerging modernization systems. These products include radar 

systems; arming, fuzing, and firing (AF&F) systems; environmental sensing devices and stronglinks; gas 

transfer systems (GTSs); joint test assemblies (JTAs);specialty engineered material products; and electrical 

and mechanical components and assemblies for secure transportation vehicles and assets. Additionally, 

KCNSC produces items for stockpile support including DoD trainers, handling gear and field testers, code 

management systems, containers and military spares. Through collaboration with Design Agencies, 

KCNSC plays a crucial role in weapons modernization and sustainment from concept through design, 

production, delivery, and lifecycle management. In addition to its nuclear weapon programs mission, the 

site supports nuclear nonproliferation, emergency management, and counterterrorism missions. The site 

also supports a global security mission that involves developing and delivering field-ready engineering 

solutions for other government agencies' national security missions.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-39

F.3.1.2 Funding

F.3.1.3 Site Capabilities

KCNSC’s capabilities support weapon systems currently in the stockpile and those being modernized via 

LEPs, Alts, and Mods. For legacy systems, these activities include Directed Stockpile Work in the 

management, production, processing, and delivery of hardware for limited life component exchanges and 

flight test systems; surveillance testing of components and materials; and maintenance and repair of 

weapons systems. For future stockpile systems, KCNSC’s work scope includes development and 

maturation of manufacturing processes and technologies, production of prototypes to support design 

development, and manufacturing of components and systems. 

KCNSC’s capabilities are used to research and develop new materials for legacy and future stockpile 

systems. Production capabilities include over 40 manufacturing technologies and manufacturing over 

1,000 unique product families, including AF&F devices; safing devices; electronics; machined parts;

polymers; plastics; and other engineered materials. KCNSC also designs, develops, and produces 

associated support equipment, tooling, fixtures, and test equipment.

KCNSC provides capabilities integral to the Stockpile Stewardship Program and the Stockpile 

Responsiveness Program. KCNSC’s primary capabilities and their associated challenges and strategies are 

described in Table F–4.

Table F–4. Kansas City National Security Campus capabilities

Non-nuclear Weapon Component Manufacturing and Assembly

KCNSC is the primary site for manufacturing and procuring non-nuclear components including AF&F systems; GTSs;

environmental sensing devices; strong links; and structural components and cushions made from engineered materials. The 

capability to manufacture and inspect these items depends on specialized equipment and facilities (cleanrooms, environmentally 

controlled areas, etc.) and the ability to maintain them (i.e., calibration and metrology). Mission success is highly dependent on 

an external and secure trusted supply chain.

Challenges Strategies

• Insufficient manufacturing, storage and 

office space to support current Program 

of Record and preparation for future 

modernization programs in Kansas City 

and New Mexico.

Current Strategy Being Implemented Future Strategies Needed

• KC STEP is a series of construction activities in 

Buildings 2 and 3 and the addition of Building 

23 to provide necessary factory capacity to 

support near term needs. KC STEP must be 

executed with minimal impact to existing 

production activities.

• KCNExT – a conceptual site 

plan for an expanded campus 

to consolidate existing office 

leases and provide additional 

manufacturing space to 

support long-term needs.

FY 2024 DOE request – site funding by source 

(total KCNSC FY 2022 request = $1,285 million)

KCNSC split for the FY 2024 Weapons Activities

President’s Budget Request ($1,231 million)
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-40

• Recruitment, retention, and availability 

of a skilled, diverse, and effective 

workforce.

• Develop long-term New Mexico plan for MGT, 

Integrated Surety Architecture Hub, weapon 

tester fabrication, and other emerging scope.

• Streamline the recruiting, hiring, and 

onboarding processes.

• Implement local and regional career fairs and 

other recruitment pipeline initiatives.

• Deploy extended reality applications to safely 

and effectively enhance employee onboarding 

and training.

• Leverage university partnerships to increase 

on-campus presence.

• Expedite clearance processing.

• Maximize onboarding efficiencies with 

training, certification, and working on 

unclassified product.

• Execute New Mexico plan.

• Expand partnerships with 

Minority Serving Institutions, 

Military Collaboration 

programs, and Student 

Veteran Organizations.

• Develop and deploy 

predictive analysis 

techniques to mitigate 

workforce fluctuations.

• See Chapter 7, “Workforce,”

for enterprise workforce 

challenges and strategies.

Testing Equipment Design and Fabrication

KCNSC designs and produces test equipment to support its mission and those of other sites within the nuclear security 

enterprise. Often, these test systems are integrated with various types of environmental conditioning equipment, such as 

thermal chambers or centrifuges, to perform automated testing for weapon environments. These test systems are vital to 

development, qualification, acceptance and long-term surveillance of weapon systems and components.

Challenges Strategies

• Ability to staff appropriately in a 

dynamic business environment with a 

cyclical workload, which is very heavy 

during the development phases and 

lighter during the production phases.

• DA-PA coordination and availability of 

definition and early hardware to support 

tester development.

• Complexity of test systems to meet 

program requirements. New capabilities 

required by emerging programs (e.g., 

shock, vibration, combined 

environments).

• Reduce the footprint required for 

production acceptance and surveillance 

test equipment

• Decrease the cost and time to deliver 

new testers.

Current Strategy Being Implemented Future Strategies Needed

• Maintain the specialized workforce in this 

area, emphasize level loading of the workload 

to the extent possible, combined with 

flexibility in assignments. Provide increased 

opportunities for challenging work 

assignments.

• Ensure milestones for test definitions and 

early hardware for tester development are 

included in weapon development schedules.

• Incorporate multi-program, multi-product 

testers, common tester architecture, and 

tester miniaturization. Design test systems for 

full lifecycle support.

• Incorporate model-based designs, digital 

information flow, simulation, and digital 

product realization within Test & 

Measurement. Upgrade design tools.

• Continue current strategies.

• Be proactive in identifying 

and applying technologies 

and capabilities that offer 

solutions to enterprise issues.

• Architect and deploy secure 

infrastructure to enable new 

technologies.

• Further incorporate tester 

miniaturization, synthetic 

instrumentation.

Fabrication and Support of Secure Transportation Assets

KCNSC prepares STA vehicles in its New Mexico facility, including fabrication, repair, and modification of tractors, trailers, and 

escort vehicles. KCNSC also supports design, fabrication, and maintenance of multiple system capabilities and facilitates safety 

engineering; technical documentation; and training of the Federal agents who perform STA functions. 

Challenges Strategies

• Inadequate manufacturing and 

development space to support MGT and 

future scope.

• Manufacturability and sourcing 

limitations of future secure 

transportation programs, which could 

increase cost and schedule risks.

• Implementing modifications and 

upgrades to existing STA systems for 

compatibility with Integrated Surety 

Architecture systems.

Current Strategy Being Implemented Future Strategies Needed

• Develop long-term New Mexico plan for MGT 

manufacturing. Includes support of ISA Hub, 

weapon tester fabrication and other emerging 

scope.

• Continue partnering with design agencies to 

ensure that, early in the process, the design 

work incorporates lessons learned from past 

trailer production and manufacturability 

reviews and facilitate multiple-sourcing 

capabilities to reduce risks and costs.

• Implement long-term New 

Mexico plan.

• Continue current strategies.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-41

• Early collaboration with design agencies to 

ensure manufacturability/sourcing risks are 

minimized.

Weapon Component Surveillance and Assessment

KCNSC supports surveillance and assessment of the Nation’s nuclear weapons stockpile through enhanced testing of various 

weapon components and materials, as well as production of telemetry, JTAs, and other hardware for laboratory and flight 

testing. The results from those tests are used to demonstrate continued performance of stockpile systems and predict, detect, 

assess, and resolve aging trends and anomalies in the stockpile. New testing and evaluation methods are also developed and 

implemented.

Challenges Strategies

• Long-term sustainment of testers to 

support weapon lifecycle surveillance 

requirements.

• Engaging workforce in older 

technologies.

• Material availability due to sunset 

technologies for legacy JTA programs.

Current Strategy Being Implemented Future Strategies Needed

• Execute the Surveillance Tester Sustainment 

Initiative plan.

• Successfully execute hiring, retention, and 

knowledge preservation strategies.

• Periodically update designs and modernize 

technology for JTA systems.

• Continue current efforts.

• See Chapter 7, “Workforce,”

for enterprise workforce 

strategies.

Advanced Manufacturing

KCNSC uses innovative technologies to maximize the efficiency and effectiveness of manufacturing processes and manufactured 

products. Some examples include Advanced Materials, Additive Manufacturing, Advanced Inspection Techniques, Digital Twins, 

Model-based Definitions, Modeling and Simulation, Automation, AI/ML, and Network and Connectivity.

Challenges Strategies

• Many Advanced Manufacturing 

concepts require enhanced/expanded IT 

and data infrastructure to connect 

equipment, information systems and 

people and to store and perform 

analytics on data.

• Attracting and retaining individuals in 

specific technology areas.

• Materials are no longer available 

because of obsolescence or supplier 

interest.

Current Strategy Being Implemented Future Strategies Needed

• Deploy Digital Transformation tenants 

including Smart Factory, Next Generation 

Enterprise Resource Planning, Enterprise 

Information Management/Big Data, and 

Digital Engineering tools.

• Partner with universities to identify and 

develop a pipeline of qualified candidates.

• Re-engineer obsolete materials and use 

microreactors to produce specialty materials 

in the right quantities and improve safety.

• Deploy increased wireless use 

capabilities, connectivity, 

Radio Frequency Identification

(commonly known as RFID) 

automated tracking, next 

generation Augmented 

Reality.

• See Chapter 7, “Workforce,”

for enterprise workforce 

recruitment and hiring 

strategies.

• Identify and leverage next 

generation disruptive 

technologies.

AF&F = arming, fuzing and firing

AI/ML = Artificial Intelligence/Machine Learning

DA-PA = design agency-production agency

GTS = gas transfer system

IT = information technology

JTA = joint test assembly

KCNExT = Kansa City Non-Nuclear Expansion

KC STEP = Kansas City Short-Term Expansion Plan

MGT = mobile guardian transporter

STA = Secure Transportation Asset

F.3.1.4 Accomplishments

◼ KCNSC achieved full rate production for B61-12 and W88 Alt 370.

◼ Kansas City Short-Term Expansion Program (KC STEP) research, development, testing, and 

engineering lab space completed early occupancy construction for equipment hotels, supporting 

test equipment, Nuclear Enterprise Assurance, and Collaborative Robot development work.

◼ KCNSC’s Supply Chain Management Center saved $165 million across the enterprise against a goal 

of $109 million, exceeding goal by 51 percent.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-42

◼ KCNSC hired a record 1,430 external employees in FY 2022, significantly more than any of the last 

3+ years, including hiring a record 103 interns. The last 4 months, KCNSC averaged 125 hires per 

month.

◼ KCNSC delivered components and assemblies to support achieving B61-12 System First 

Production Unit one week ahead of schedule.

◼ KCNSC completed last production unit deliveries for W76-1/Mk4A products in calendar year 2022.

◼ KCNSC established the capability to create next generation Direct Ink Write tooling by 3D-printing 

of Carbon Fiber-Polyetherketoneketone mandrels. This process saves 80 days of flow time and 

$50,000 for each mandrel relative to the legacy machined aluminum mandrels. Test Engineering 

Dashboard technologies enabled avoidance of over 2,600 non-conformance-report-eligible 

events.

◼ KCNSC developed a joint strategy for 3D Interactive Viewable end-to-end production 

demonstration and provided SNL with information to inform improvements in the model-based 

product definition effort. SNL is also leveraging Model Based Definition for mechanical part design 

and definition by generating higher quality CREO models with 3D annotations that allow earlier 

design feedback from KCNSC.

◼ KCNSC introduced Curie, itslatest high-powered computer, which doubled its computing capacity 

and supports advanced simulations needed to help solve some of the nation’s most complex 

national security challenges.

◼ KCNSC achieved Auxiliary Module first production unit for W88 Alt 940 12 days ahead of schedule 

and shipped to the customer 5 days ahead of schedule, beginning production of critical Integrated 

Surety Architecture components.

◼ KCNSC achieved first production unit for MC4972-1 Common High Efficiency Adaptable Telemetry 

Transmitter 1 month early; the Common High Efficiency Adaptable Telemetry Transmitter is a 

multi-program JTA transmitter.

◼ KCNSC deployed big data solutions, including the Test Engineering Dashboard, to monitor test 

system health using data science and artificial intelligence to avoid over 2,600 non-conformancereport-eligible tester events in FY 2022 as well as a system to perform automated analysis and 

anomaly detection of Record of Assembly data which has virtually eliminated Record of 

Assembly-related escapes.

F.3.1.5 Kansas City National Security Campus Workforce

Total headcount at KCNSC continues to grow year over year to support its growing scope of new LEP and 

Mod programs. KCNSC hired a record number of 1,430 new employees in FY 2022 and has more than 

doubled its headcount over the last 6 years. KCNSC continues to leverage an increased focus on university 

and industrial partnerships, recruiting and hiring events, and 

streamlining hiring and onboarding processes to support this growth. 

Modest growth is expected to continue in the coming years.

The average age of employees at KCNSC continues to decrease, going 

from 41.8 at the end of FY 2020 to 40.9 at the end of FY 2022. 

Employees 35 years of age and under account for 42.7 percent of all employees, and 56.9 percent are age 

40 and younger. Average years of service at KCNSC remains relatively flat, increasing from 8.34 in FY 2020 

to 8.85 in FY 2022, and years of service distribution is shown below. Employees that are retirement 

eligible decreased from 16 percent in FY 2020 to 12 percent in FY 2022.

Early Engagement in FY 2022

Interns: 112
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-43
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-44

Most of the voluntary separations (45.5 percent of all separations) come from the age group of 26–40, 

and retirements accounted for 20.4 percent of all separations. Two-thirds (66.3 percent) of all separations 

were from employees with 5 years of service or less at KCNSC and more than three quarters (77.4 percent) 

of all separations were from employees with 10 years of service or less at KCNSC, as shown in 

Figure F–17. Voluntary separations increased from 182 in FY 2020 to 504 in FY 2022, likely attributable to 

the ending of the COVID-19 pandemic and changes in the job market.

Figure F–17. KCNSC separations by years of service

A substantial portion (nearly 75 percent) of the workforce at KCNSC are in the early- and mid-phases of 

their careers in the nuclear security enterprise, as shown in Figure F–18. Nearly 70 percent of employees 

have 5 years of service or less at KCNSC, and 82.1 percent have 10 years or less of service. KCNSC is taking 

active steps to preserve and transfer knowledge from those with significant experience in the nuclear 

security enterprise. The People Center of Excellence at KCNSC has established a Knowledge Management 

Team to establish processes for preserving knowledge before subject matter experts with over 30 years

of experience retire. Prototypes for some of these efforts were developed in FY 2022; testing with pilot 

groups continued through FY 2023.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-45

Figure F–18. KCNSC workforce participation trends by age category and percent advanced career

Figure F–19. KCNSC employee separation trends
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-46

Figure F–20. KCNSC workforce projection needs by Common Occupational Classification System1

1 Facilities and infrastructure are a limiting factor on workforce growth. Projections reflect early business cycle preliminary 

estimates.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-47

F.3.2 Pantex Plant

F.3.2.1 Mission Overview

Pantex Plant (Pantex) is integral to national security interests and has adapted to emerging needs and 

delivered solutions for the Nation for more than 75 years. Pantex, located outside of Amarillo, Texas, is 

the only DOE/NNSA site authorized to assemble or disassemble nuclear weapons. The Weapons 

Assembly/Disassembly capability is central to nuclear weapons production, and this includes assembly, 

disassembly, refurbishment, maintenance, alteration, and surveillance of stockpile nuclear weapons and 

weapon components, as well as dismantlement of retired stockpile nuclear weapons.

As DOE/NNSA’s High Explosive Production Center of Excellence, Pantex provides cradle-to-grave HE 

products and services for the nuclear security enterprise. Pantex manufactures and delivers War Reserve 

HE main charges and boosters for all weapon programs through synthesis; formulation; pressing; 

machining; component assembly; and chemical, mechanical, safety, and performance testing. Pantex also 

tests stockpile returns for all weapon programs through small component disassembly; machining; 

chemical, mechanical, performance, and safety testing; and final disposition. As a collaborative partner 

with the national security laboratories, Pantex provides capabilities to transition HE R&D from bench-scale 

to production-scale. In addition, Pantex collaborates and provides capabilities to DoD, the 

United Kingdom, universities, and commercial vendors. 

Pantex also supports the reduction of global nuclear threats through its nonproliferation activities.

F.3.2.2 Funding

FY 2024 DOE request – site funding by source 

(total Pantex FY 2024 request = $1,209 million)

Pantex split for the FY 2024 Weapons Activities

President’s Budget Request ($1,196 million)
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-48

F.3.2.3 Site Capabilities

Pantex’s mission capabilities include manufacture of specialty explosives; fabrication and testing of HE 

components; assembly, disassembly, refurbishment, maintenance, alteration, and surveillance of 

stockpile nuclear weapons and weapon components; dismantlement of retired weapons; sanitization and 

disposition of components from dismantled weapons; interim staging and storage of nuclear components 

from dismantled weapons; pit requalification; pit surveillance; and pit packaging (including container 

surveillances and recertification).

Pantex’s key capabilities and their associated challenges and strategies are described in Table F–5.

Table F–5. Pantex Plant capabilities

Weapons Assembly and Disassembly

Assembly and disassembly of nuclear explosive warheads and bombs, assembly and post-mortem analysis of JTAs, assembly 

and disassembly analysis of test bed units, and electrical and mechanical tests of weapons and weapon components.

Challenges Strategies

Development, establishment, and 

implementation of the Documented Safety 

Analysis process for new programmatic 

weapons activities.

Current Strategy Being Implemented Future Strategies Needed

While vast improvements have been made, 

continue to streamline the Documented 

Safety Analysis process methodology for 

efficiency and effectiveness.

Continue current strategy.

Weapons Assembly/Disassembly facilities 

continue to age and will require 

replacement at some point.

• Continue modernizing the existing bays 

and cells. 

• Conduct aging studies and develop 

strategy and required timing for 

replacement of bays and cells with new, 

modern assembly/disassembly facilities.

Continue current strategies.

Surveillance

Nondestructive evaluation of pits and weapon components from stockpile units to support the Annual Assessment Reports and 

destructive and nondestructive evaluation of HE from stockpile units.

Challenges Strategies

Production downtime associated with 

aging pit surveillance equipment.

Current Strategy Being Implemented Future Strategies Needed

Develop and evaluate options for upgrading 

or acquiring replacement equipment.

Continue current strategy.

High Explosives

Pantex is responsible for conventional HE and insensitive HE manufacturing, qualification, and assembly for LEPs and stockpile 

rebuilds; disassembly and disposition of HE from surveillance and dismantlement units; and manufacturing, and qualification, 

and assembly of mock HE for JTAs.

Challenges Strategies

Programmatic infrastructure (i.e.,

equipment) is aging, and some of the 

general-purpose infrastructure (i.e.,

buildings) is Manhattan-era.

Current Strategy Being Implemented Future Strategies Needed

• Planned projects such as the HE Science 

and Engineering; HE Synthesis, 

Formulation, and Production; and the HE 

Component Assembly facility are 

recapitalizing end-of-life equipment needs 

and establishing major modernization

plans.

• Continue replacement of end-of-life HE 

machining equipment. 

Continue line-item planning, and 

coordination with DOE/NNSA.

Initiate construction of 

replacement HE facilities as 

capacity allows.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-49

Special Nuclear Material Accountability, Storage, Protection, Handling, and Disposition

These capabilities involve requalification for pits for LEPs and storage of pits and weapons.

Challenges Strategies

Pit storage capacity to support future 

directed stockpile work and production 

downtime associated with aging pit 

requalification equipment.

Current Strategy Being Implemented Future Strategies Needed

Implement pit staging projects to 

reconfigure operational facilities to 

increase the site storage capacity to 

address near-term staging constraints

until the Material Staging Facility project 

is re-started. Implement actions to 

revitalize Zone 4 infrastructure to ensure 

staging capabilities are sustained until 

Material Staging Facility completion. 

Deploy new requalification equipment 

for upcoming LEPs. Upgrade existing 

requalification equipment.

• Continue implementation of pit 

staging projects and equipment 

upgrades.

• Continue implementation of the 

Zone 4 Bridging Strategy 

Implementation Plan.

HE = high explosive

JTA = joint test assembly 

LEP = life extension program

F.3.2.4 Accomplishments

◼ Completed the first production unit for the B61-12; completed the B61-12 JTA first production 

unit at Pantex.

◼ Met all external shipment commitments to DoD customers.

◼ Pantex shipped initial operational capability quantities for the W88 Alt 370 to the Navy, on 

schedule, representing a significant accomplishment for the nuclear security enterprise.

◼ Exceeded canned subassembly dismantlement schedule.

◼ Established the Pantex Production Optimization, a cross-functional team created to maximize the 

output of Pantex production for near-term Directed Stockpile Work deliverables and to ensure 

sustainable stewardship of future Directed Stockpile Work deliverables at the site.

◼ HE Science and Engineering Facility: Critical Decision (CD)-2/3 authorization was received in 

April 2022, and the main construction subcontract was awarded in April 2022.

◼ Construction continues on schedule for the Advanced Fabrication Facility, which will provide 

expanded capability for non-hazardous machining operations, thereby expanding capacity for 

hazardous material machining in the HE facilities.

◼ The Flexible Support Facility, which provides housing for around 90 personnel for on-site project 

and maintenance teams, held a ribbon-cutting in February 2023.

F.3.2.5 Pantex Plant Workforce

Total headcount has continued to increase year over year, from 3,807 at the end of FY 2021 to 4,095 at 

the end of FY 2022. Significant recruiting and hiring efforts replaced vacancies from attrition and built the 

technical skill base in preparation for the increased workload in FY 2022 and beyond. The workforce has 

a fairly even age distribution while recent increases in hiring mean that almost half of employees have 

less than 5 years of service with 18.6 percent of full-time employees are eligible for retirement.1

1 Retirement eligibility is calculated with the following method: Age 55 with 10 years of service, age 65 with 5 years of service, or

Pantex exempt/nonexempt age 50 with 10 years of service.
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Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-51

Figure F–21. Pantex separations by years of service

As shown in Figure F–22, Mid-Career continues to comprise the largest age category; for the first time in 

10 years, workforce participation in the 35-to-50-year-old range surpassed over 50-year-old employee 

participation. Early Career continues increasing with hiring, while Advanced Career slowly decreases.

Figure F–22. Pantex workforce participation trends by age category and percent advanced career
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-52

As Figure F–23 shows, over half of separations are due to retirements. The average age of retirees is 

increasing as more retirement-eligible employees are electing to work longer, and many workers choose 

not to retire until after age 66 so they can receive full social security benefits. Pension plans were phased 

out for new hires around 2012 and were replaced by enhanced 401(k) plans. Voluntary separations 

continue trending upwards, and retention efforts are ongoing. Involuntary terminations have returned 

to pre-COVID-19 pandemic levels. 

Figure F–23. Pantex employee separation trends

Workforce projections, shown in Figure F–24, are now made using a robust suite of human resource

management tools; in FY 2021 the Multi-Year Staffing Plan for Headcount was integrated to the suite of 

tools, improving their accuracy. While the total estimated number of 

personnel needed to support work in the near term is relatively static, 

Pantex anticipates hiring for attrition replacement, with emphasis on 

engineers, safety basis, information technology, technicians, and 

security. Crafts, technicians, and administrators typically have lower 

attrition, while engineers have higher attrition due to high national demand. Pantex is working with Oak 

Ridge Associated Universities through the Supply Chain Management Center to improve sourcing and 

recruiting capabilities and is working with local students to expose them to Pantex’s unique mission.

Early Engagement in FY 2022

Students: 18
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-53

Figure F–24. Pantex workforce projection needs by Common Occupational Classification System2

2 FY 2024 and FY 2025 headcount is based on actual FY 2024 program plans and anticipated funding for FY 2025 scope. Projections 

for FY 2026 and beyond reflect a stable work scope and funding, pending finalization of outyear funding projections.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-54

F.3.3 Savannah River Site

F.3.3.1 Mission Overview

The Savannah River Site (SRS), which spans Aiken, Allendale, and Barnwell Counties in South Carolina, 

includes mission areas in tritium supply, stockpile maintenance, stockpile evaluation, tritium R&D, and 

helium-3 recovery. Missions at SRS are also expanding to include plutonium pit production through the 

Savannah River Plutonium Processing Facility (SRPPF). SRS is managed by the DOE Office of Environmental 

Management with DOE/NNSA as a tenant, making it unique across the nuclear security enterprise sites. 

Approximately 58 percent of the SRS M&O workforce is dedicated to NNSA missions. DOE/NNSA pays its 

share of an indirect allocation for personnel to maintain infrastructure and services (e.g., roads, steam, fire 

water, electricity, medical, emergency services personnel). Of note, DOE/NNSA plans to take over managing 

SRS over the next 2–3 years. A transition team consisting of NNSA-Headquarters and Savannah River Field 

Office personnel is currently working all plans necessary to complete this effort. The scope of the Office of 

Defense Programs work resides in the Savannah River Tritium Enterprise1(SRTE), which is managed as a 

separate entity within SRS, and through the Plutonium Sustainment Program and the planned SRPPF. 

F.3.3.2 Funding

FY 2024 DOE request – site funding by source 

(total SRS FY 2024 request = $3,045 million)

SRS split for the FY 2024 Weapons Activities

President’s Budget Request ($1,347 million)

1 SRTE is the collective term for the facilities, capabilities, people, and expertise at SRS related to tritium, and the SRTE umbrella 

extends beyond the tritium area to include vital mission-support functions. Unless otherwise noted, the information in this 

appendix will reference SRTE.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-55

F.3.3.3 Site Capabilities

SRS has unique capabilities related to nuclear weapon limited life components (LLC) and the broader 

national security mission of reducing global nuclear security threats to the United States and its allies. 

Tritium is a critical component of the Nation’s defense systems and must be continually replenished to 

meet deterrent needs. SRS conducts large-scale tritium operations, and SRTE is the DOE/NNSA Center of 

Excellence Involving Large Quantities of Tritium. To sustain the tritium inventory, tritium is obtained from 

two sources: recovery from end-of-life GTS reservoirs that are returned to SRS and extraction from 

irradiated tritium-producing burnable absorber rods (TPBARs) received from the Tennessee Valley 

Authority. 

SRPPF will support plutonium pit production by repurposing the former Mixed Oxide Fuel Fabrication 

Facility (MFFF) into a safe, secure, compliant, and efficient pit production facility. The former MFFF is a 

Security Category 1/Hazard Category 2 structure that provides an opportunity to achieve pit production 

in a facility designed to meet stringent security and safety requirements for plutonium operations. As 

described in Chapter 3, Section 3.1.1.3, SRPPF will provide a sustained production capacity of no fewer 

than 50 War Reserve ppy as close to 2030 as possible.

SRS’s key capabilities and associated challenges and strategies are described in Table F–6.

Table F–6. Savannah River Site capabilities

Tritium Recycling (Tritium Recycle and Recovery Program)

Systems for recovering and recycling tritium from returned GTS reservoirs.

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Tritium inventory systems contain LLCs, many 

of which are nearing life expectancy. 

Recovering the contents of the LLCs requires 

careful planning and coordination to avoid 

mission interruption. 

In the short-term, schedule replacement 

projects to maximize efficiency and reduce 

impact on operating schedules. 

In the long-term, deploy new 

technologies to enhance 

system operating efficiency 

and reduce footprint. 

Tritium Extraction (Tritium Modernization Program)

Tritium extraction from irradiated TPBARs.

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

To meet supply requirements, SRTE requires 

additional workforce with training, 

qualifications, and proficiencies.

SRTE examines multi-year staffing needs and 

develops appropriate processes to ensure a 

continuous pipeline of knowledge, skills, and 

abilities to sustain tritium capabilities.

Continue to examine multiyear staffing needs and work 

on retention of current 

employees through

leadership engagement and 

focus on career 

development.

Replenishing Tritium in Gas Transfer System Reservoirs

Replenishing tritium in GTS reservoirs.

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Maintain facilities and equipment to support 

stockpile deliverables and future warhead 

modernization activities.

SRTE uses a strategic investment process and 

prioritizes its infrastructure needs to ensure 

mission continuity. Priorities are identified 

through engineering analysis and risk 

assessment, vetted by leadership teams, and 

captured on a strategic roadmap and integrated 

priority list. This process also includes 

infrastructure and equipment improvements.

Continue current strategy. 
Department of Energy/National Nuclear Security Administration | November 2023

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Addressing infrastructure needs in a highhazard area without interrupting the mission 

schedule while adapting for multiple, more 

complex operations.

SRTE is modifying the process and 

infrastructure equipment and executing a 

strategic investment process to ensure 

continuity. SRTE is also evaluating critical 

systems to ensure optimal product capacity 

while carefully planning the production outages 

to maximize benefit. Obsolete systems are 

being replaced to ensure adequate risk until 

long term plans are completed. 

Completing the Tritium 

Finishing Facility will reduce 

mission risk and provide 

long-term, safe operations. 

Gas Transfer System Surveillance and Tritium Research and Development

SRTE function testing for GTS surveillance and tritium R&D.

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Maintaining original, specialty engineered 

equipment.

SRTE is initiating R&D projects in a clean 

environment to test specialty engineered 

equipment for future facility application. 

Planning extended outages to incorporate 

rework if needed due to tritium environment.

Develop Tritium R&D 

capability and execute R&D 

projects for development of 

replacement specialty 

engineered equipment.

SRS Plutonium Modernization

Proposed pit production mission at SRS.

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

• Navigating procurement challenges 

associated with supply chain shortages, 

which has also caused prices to increase 

dramatically

• Hiring and retaining a qualified workforce 

capable of supporting the construction 

project and the enduring Pu Modernization 

mission once the facility is operational

Implement a tailored approach to achieve CD-2 

(Approve Performance Baseline) and CD-3A 

Long Lead Procurements, to support producing 

50 WR ppy as close to 2030 as possible.

Re-establish the supply chain 

for weapons-related 

components and 

commodities needed to 

support the 50 ppy mission.

CD = Critical Decision

GTS = gas transfer system

LLC = limited life component 

MFFF = Mixed Oxide Fuel Fabrication Facility

ppy = pits per year

SRTE = Savannah River Tritium Enterprise

TPBAR = tritium-producing burnable absorber rod

WR = War Reserve

F.3.3.4 Accomplishments

◼ Delivered all LLC exchanges, JTAs, and minor Alts on schedule. Accommodated 34 schedule 

changes inside 90-day window. 

◼ Met all tritium mission deliverables with 100 percent on-time shipment, and far exceeded all 

standards for product quality. 

◼ Completed the first B61-12 loading run, unloaded a W76 GTS reservoir for the first time, loaded 

commitments on all five operational load lines, loaded more tritium in January 2022 than in any 

month since 2011, completed the most unloading runs in August 2022 than in any month since 

2011, received two shipments in one day from the Tennessee Valley Authority for the first time, 

and loaded four cylinders of helium-3.

◼ Enhanced Knowledge Transfer collaboration to support pit production at both SRS and LANL.

◼ Developed a solution with LLNL to execute High-Fidelity Training and Operations Center plans that 

will modernize training and accelerate the SRPPF path to full plant operations. 

◼ Managed three Capital Projects concurrently. 

◼ Submitted the SRPPF CD-3A Demolition and Removal package along with six contract packages to 

accelerate the start of work. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-57

◼ Delivered the SRPPF design performance baseline, including strategies to accelerate procurement 

and construction activities, thereby minimizing time needed to achieve CD-4 delivery.

◼ Initiated construction of the Tritium Finishing Facility site preparation sub-project.

F.3.3.5 Savannah River Site Workforce2

The SRS M&O workforce is dedicated to the NNSA Weapons Activities mission. The scope of the Office of 

Defense Programs work resides in the Savannah River Nuclear Solutions (SRNS) Tritium organization, and 

the NNSA Capital Project team for the NNSA line-item projects. In FY 2023, several traditionally direct 

Tritium resources (i.e., engineering, risk, maintenance, continuous improvement, and radiological 

controls) were moved from the Tritium reporting organization (i.e., SRTE) to a site functional organization. 

These personnel will continue to support the tritium scope full time in a matrixed capacity. They will also 

continue to be included in the employee site count. The plutonium scope continues to be managed as a 

separate organization under the NNSA Capital Projects group.

2 All workforce numbers account for the STRE and Plutonium missions at SRS. 
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-58

The Tritium and Plutonium programs continued to execute an aggressive strategic hiring plan to meet 

mission needs. The SRTE organization experienced steady attrition through FY 2021, consistent across 

the nuclear security enterprise, but in FY 2022, SRTE experienced more than double the attrition

forecasted, as shown by the large change from FY 2021 to FY 2022 in Figure F–27. Figure F–25 breaks 

down these separations by years of service. SRNS is reviewing compensation practices, teleworking, and 

benefits programs to increase retention. 

Figure F–25. SRTE and Plutonium separations by years of service

As Figure F–26 shows, increased and sustained hiring, combined with a steady level of retirement and 

transfers or promotions to other opportunities, has led to an increase in early career and mid-career 

workers and a decrease in the advanced-career populations at SRNS-Tritium, as well as in the newer 

plutonium mission. The mid-career population will continue to be monitored to help ensure career 

development opportunities are available to retain and grow the workforce. This effort, combined with 

compelling workplace improvements, should impact all career groups in a positive way.

SRNS-Tritium continues to plan and execute workforce growth commensurate with mission requirements 

to recapitalize process equipment and surrounding infrastructure, increasing GTS work scope due to LEPs, 

and expected retirements; it is working to hire ahead-of-need to allow time for security clearance and 

training processesfor new personnel. As shown in Figure F–27, voluntary separations increased as a result 

of promotional opportunities on site and mission-related business needs. Workforce retirement is 

expected to remain steady over the next 5 years. SRS strives to remain aware of the constantly changing 

business conditions and environment, continue to hire replacements and workers to support increased 

work scope, and to retain new employees by providing meaningful work, leadership engagement, 

development opportunities and a compelling place to work.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-59

Figure F–26. SRTE and Plutonium trends by career stage and percent advanced career

Figure F–27. SRTE and Plutonium employee separation trends
Department of Energy/National Nuclear Security Administration | November 2023

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Figure F–28 reflects expected mission growth primarily due to the Tritium Extraction Facility tritium supply 

production increase; the plutonium mission; increased project activity; and a growing effort to reduce the 

maintenance backlog on facilities and infrastructure; and implementation of Nuclear Enterprise Assurance 

requirements. SRTE will also experience some growth in reservoir processing and surveillance due to 

increases in workload complexity to support LEPs. Workforce growth will increase housing requirements, 

including the need for new office space. In addition to mission increases, SRS will continue to manage 

steady attrition (retirements and resignation) and employee retention. 

In order to respond to continued steady attrition and increased mission needs, the SRS strategic staffing 

plan is aligned to funding and monitored closely each month. Adequate 

and timely funding to allow hiring in advance is crucial. SRS has 

established partnerships with local universities, implemented an 

apprenticeship program, and increased social media presence to attract 

candidates. have provided opportunities for graduates to be hired. 

Corporate reachback and restructured staffing forecast and recruiting 

practices offer greater organizational efficiencies and external sources of experienced personnel. 

Workforce retirement is expected to remain steady over the next several years and overall attrition

predicted to level out from the significant spike experienced in FY 2022 due to ongoing engagement and 

development efforts as well as compensation and benefit program enhancements. In FY 2022, voluntary 

separations increased significantly. These were attributed to transfers to other opportunities on site 

(Defense Nuclear Nonproliferation missions, DOE Office of Environmental Management missions, and 

Savannah River National Laboratory) and other off-site opportunities. 

Figure F–28. SRTE and Plutonium workforce projection needs by Common Occupational 

Classification System

Early Engagement in FY 2022

Interns: 7
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-61

F.3.4 Y-12 National Security Complex

F.3.4.1 Mission Overview

The Y-12 National Security Complex (Y-12) is integral to national security interests. The site has adapted

to emerging needs and delivered solutions to support national security missions for more than 75 years. 

The site is committed to:

◼ Taking decisive action to maintain existing capabilities, increase throughput capacity, and 

complete new mission requirements

◼ Meeting increasing mission deliverables and making infrastructure improvements in the nearterm while simultaneously positioning our site for long-term success

◼ Finding innovative solutions while adjusting to a changing geopolitical landscape, growing NNSA 

missions, shifting workforce dynamics, and lingering impacts of a global pandemic

Y-12 provides capabilities instrumental to NNSA missions and priorities, including producing uranium 

weapon components and subassemblies for the Office of Defense Programs; recycling retired weapon 

components and production by-products; producing feedstock for naval and research reactors;

supporting nuclear nonproliferation and global security; special materials processing and production; and 

storing the nation’s highly enriched uranium inventory. This mission encompasses many facilities and 

processes for enriched and depleted uranium. Y-12’s strategy aims to enhance nuclear safety and reduce 

the risk of mission interruption inherent in aging facilities and processes while maintaining critical mission 

capabilities.

For more than 70 years, Y-12 has produced and recycled enriched lithium to support life extension 

programs, joint test assemblies, and strategic partnership projects. Because of this work, the nation can

maintain a functional, effective nuclear deterrent. The lithium capability requires specialized areas and 

equipment to chemically process, machine, inspect, assemble, certify, disassemble, and store materials.

Y-12 recently reestablished a lithium purification capability to augment a limited inventory of recycled 

material to meet demands until the Lithium Processing Facility becomes operational. The deteriorating 

condition of aging lithium processing facilities and limited material supply pose significant risks to our 

ability to meet current and future Defense Programs requirements. Y-12 has worked with the NNSA to 

develop a lithium strategy that will ensure the capability is maintained.

Y-12 has handled, processed, and stored a majority of the Nation’s special nuclear materials. The site has

a dynamic operating envelope that includes multiple high-security facilities, classified networks and 

information systems, critical infrastructure and equipment, and skilled personnel. As mission and project 

scope expand—bringing additional people on-site, increasing special nuclear material operations, and 
Department of Energy/National Nuclear Security Administration | November 2023

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inserting more project work into operating facilities—the challenge of executing security measures also 

grows.

Y-12’s strategic approach includes restarting equipment, processes, and material streams that have not 

been operational since the Cold War ended. With national policy indicating that future activities may 

include the design and build of new weapon systems, Y-12 is working to establish the skills, processes, 

infrastructure, equipment, and technology needed to support a broad range of weapon activities and 

systems.

Y-12 exists to sustain and modernize the nuclear weapons stockpile, provide feedstock for naval 

propulsion, and support nuclear threat reduction. Accomplishing Y-12’s national security missions depend

not only on the hands-on workers who execute core capabilities but also on the thousands of other 

workers who provide expertise in safety, security, emergency management, business, training, 

maintenance, and management. At Y-12, every employee is essential to delivering or enabling the

mission. The site aspires to develop the capability to fabricate any component, build any weapon, and 

qualify any system on any day and to digitally transform from a “document control” culture to a real-time, 

information-driven culture. Y-12’s actions in support of NNSA’s mission priorities will help to protect the 

Nation, its allies, and its partners by providing resilient and a responsive production and manufacturing 

site.

F.3.4.2 Funding

FY 2024 DOE request – site funding by source 

(total Y-12 FY 2024 request = $2,580 million)

Y-12 split for the FY 2024 Weapons Activities

President’s Budget Request ($2,485 million)

F.3.4.3 Site Capabilities

Key mission capability areas at Y-12 are primarily uranium and canned subassembly production, lithium,

and material and process R&D. Critical to all of these capabilities is the supporting infrastructure that 

provides power, water, and other services. Y-12’s key capabilities and their associated challenges and 

strategies are described in Table F–7.
Department of Energy/National Nuclear Security Administration | November 2023

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Table F–7. Y-12 National Security Complex capabilities

Uranium and Canned Subassembly Production Capability

Y-12 produces uranium weapon components to refurbish the Nation’s nuclear stockpile, and recycles and reprocesses the 

Nation’s existing supply of enriched uranium. The recycled metal serves as feedstock for the Navy’s nuclear-powered 

submarines and aircraft carriers, commercial power reactors that generate U.S. electricity, medical isotope production, and 

some domestic and foreign research reactor programs. Y-12 also helps recover and secure at-risk nuclear materials around the 

globe. The Highly Enriched Uranium Materials Facility at Y-12 houses the Nation’s cache of weapons-grade uranium. The 

Uranium Processing Facility now under construction will be a state-of-the-art facility for the enriched uranium operations that 

are currently performed in Building 9212. 

Depleted Uranium operations produce and maintain a reliable inventory of depleted uranium, depleted uranium alloy, and 

other non-nuclear industrial material components and tooling through a variety of metalworking processes in support of LEPs, 

JTAs, and other national security and government programs. 

Challenges Strategies

To continue supporting all uranium missions, 

Y-12 must address its aging infrastructure.

Current facilities are aging, necessitating

sustainment through the Extended Life 

Program. Enriched uranium capabilities must 

be maintained while the Uranium Processing 

Facility is being constructed, which 

necessitates relocating enriched uranium 

functions to other Y-12 facilities, and startup 

and proving of replacement technologies 

before uranium programmatic operations 

cease in current facilities by 2025. Y-12 must 

also complete reduction of material-at-risk 

quantities in current processing facilities by 

consolidating storage into the HEU

Manufacturing Complex.

Current Strategy Being Implemented Future Strategies Needed

The Uranium Processing Facility will 

replace most of the HEU production 

functions currently performed in 

Building 9212. The uranium strategy also 

includes upgrades and advanced 

technologies that will be started in existing 

facilities.

Additional replacement facilities 

Enriched Uranium Manufacturing 

Center and Assembly and

Disassembly Capability will be 

needed and are currently

planned for the late 2030s and 

2040s.

Depleted uranium infrastructure is aging. 

Increased throughput and capacity, which 

includes additional equipment and personnel,

is required for future programs.

• Purchase the limited commercial HPDU 

supplies available. Invest in feedstock 

capabilities to ensure there is a steady 

stream of HPDU in the future.

• Invest in maintaining the legacy alloying

processes. Plan to purchase additional 

equipment to reduce the strain on 

legacy equipment and processes.

• Identify bottlenecks and develop 

bridging strategies to fulfill near-term 

mission requirements should new 

technology not be employed in the 

immediate future

Replace depleted uranium 

fabrication/manufacturing 

functions in current facilities with 

the Agile Radiation Case and 

Component Capability.

Lithium Capability

Y-12 provides material purification, material preparation, component fabrication and inspection, salvage operations, and 

storage for lithium operations to support LEPs, JTAs, and complementary work.

Challenges Strategies

Current lithium capabilities are housed in a 

Manhattan Project-era facility with

infrastructure well beyond its expected life 

and rapidly deteriorating. The process 

equipment is inefficient for its current mission

scope, is rapidly deteriorating, and has far

exceeded its life expectancy. Current lithium 

production capabilities will be placed under 

additional strain because of material supply

Current Strategy Being Implemented Future Strategies Needed

• DOE/NNSA’s lithium strategy necessitates 

sustaining the current infrastructure,

sustaining the supply to meet customer 

demand, and maturing and deploying

technologies to replace hazardous 

processes.

• Continue to maintain legacy 

processing lines of effort 

through identified facility 

lifecycle extension projects 

until the Lithium Processing 

Facility is fully operational.
Department of Energy/National Nuclear Security Administration | November 2023

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issues and the projected increase in mission 

scope. Combined, these challenges represent 

significant risk to the mission.

• Design and construct the Lithium 

Processing Facility.

• Future projects to maintain 

capability include electrical, 

utility upgrades, and other 

identified structural life 

extending efforts.

Material and Process Research and Development Capability

Y-12’s Development Division serves as the focal point for development and preservation of uranium and lithium materials 

sciences and manufacturing technologies. R&D activities include material and metallurgical synthesis, forming, evaluation 

techniques and processes, material purification, and material characterization. Advanced technologies have been developed 

and are at varying stages of deployment readiness for enriched uranium and lithium. 

Challenges Strategies

Development is essential to Y-12’s production

mission, providing a ready pool of subject 

matter experts to tackle production problems, 

developing new technology to meet future 

production requirements, and performing

strategic partnership projects as needed to 

support global security missions. Aging 

electrical, cooling water, and other process 

support systems in Y-12’s infrastructure 

increase risk to mission work as the 

infrastructure ages. 

Current Strategy Being Implemented Future Strategies Needed

The current strategy for development 

includes modernization of the NNSAprocured off-site 103 Palladium facility for 

subsequent relocation and installation of 

designated Development capabilities. 

Implementation of electrical and cooling 

water system recapitalization projects within 

existing Development facilities will address 

infrastructure concerns, until replacement 

facilities are available.

The development strategy 

ultimately results in either a 

new line-item replacement

facility (Applied Technologies 

Laboratory) or multiple 

campus-like buildings to 

consolidate remaining 

development capabilities and 

the continued use of the 103 

Palladium facility for the 

relocated Development 

capabilities. 

HEU = highly enriched uranium

HPDU = high-purity depleted uranium

JTA = joint test assembly

LEP = life extension program

F.3.4.4 Accomplishments

◼ Achieved full rate production for the B61-12 and the W88 Alt 370.

◼ Legacy Risk Reduction continued in Uranium Processing through early deactivation and clean-out 

of systems no longer in use in Building 9212 and the dispositioning of material at risk. Completely 

eliminated a backlog of legacy enriched uranium briquettes, representing some of the highest 

hazard materials stored on the site.

◼ Y-12 advanced the Lithium Strategy, ensuring adequate supply of lithium for stockpile work until 

the Lithium Processing Facility reaches beneficial occupancy.

◼ A Y-12 team completed the removal and shipment of highly enriched uranium from Japan, 

wrapping up a 4-year effort that included overcoming hurdles of travel and shipping during the 

pandemic.

◼ Achieved significant improvements in infrastructure modernization:

– The Uranium Processing Facility’s Personnel Support Building and the Main Process Building 

both achieved full enclosure, putting the entire Uranium Processing Facility Project “in the 

dry.”

– Y-12’s Emergency Operations Center and Fire Station, both pilot commercial-like build 

projects, were completed. Y-12 also completed the transition of plant power loads from 

Elza-1 to the new Pine Ridge Substation.
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F.3.4.5 Y-12 National Security Complex Workforce

Total headcount increased from 7,315 at the end of FY 2021 to 7,602 at the end of FY 2022; these numbers 

include limited term employees, who add about 1,400 to the permanent headcount. Significant recruiting 

and hiring efforts filled vacancies from attrition and built the technical skill base in preparation for the 

increased workload in FY 2022 and beyond. These workforce efforts included developing new tools for 

planning headcount; recruitment efforts towards sourcing with a “Make, Take, Attract” model; and efforts 

to reduce the full onboarding cycle time to avoid losing candidates in the onboarding period. Over half of 

the workforce has 0–5 years of experience, indicating that Y-12 is replenishing its workforce for future 

needs and offsetting attrition due to retirements and other separations.
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Figure F–29 shows that the demographic experiencing the greatest 

number of voluntary separations is those with 0–5 years of service, which 

correlates with their large share of the workforce. Data from optional exit 

interviews show the top three reasons for leaving Y-12: career 

advancement opportunities, flexible work options, and compensation. 

Y-12 addressed these concerns by enacting several changes, including 

increased teleworking for select positions, improved work environments, implemented talent 

management opportunities for career development, improved clearance processing cycle time by 

increasing investigators, and redesigned compensation to attract and retain candidates with critical skills. 

Retention is on a positive trend.

Figure F–29. Y-12 separations by years of service

Early and mid-career levels and total population grew due to increased hiring as shown in Figure F–30. 

Many advanced career employees are electing to work longer, and the percentage of advanced career 

personnel is relatively stable. The increase in Early Career levels to 24 percent of the workforce is partially 

due to including limited term employees, who are more often 35 years old or younger.

Early Engagement in FY 2022

Students: 38
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Figure F–30. Y-12 workforce participation trends by age category and percent advanced career

As Figure F–31 shows, over half of separations are due to retirements. The average age of retirees is 

increasing as more retirement-eligible employees are electing to work longer. Several factors contribute 

to this shift, such as better health and cognitive activity, opportunity to telecommute, and uncertainty 

about the pandemic and itsimpact on travel, family, and the economy; additionally, many workers choose 

not to retire until after age 66 so they can receive full social security benefits. Pension plans were phased 

out for new hires around 2012 and replaced by enhanced 401(k) plans; this change removed the perceived 

retirement trigger (pension eligibility at age 55 with 10 years of service) for those hired after 2012. 

Voluntary separations continue trending upwards, and involuntary terminations have returned to 

pre-pandemic levels. 

Figure F–31. Y-12 employee separation trends
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page F-68

Workforce projections, shown in Figure F–32, are now made using a robust suite of Human Resources

management tools. In FY 2021, the Multi-Year Staffing Plan for Headcount was integrated to the suite of 

tools, improving their accuracy. Y-12 anticipates hiring for attrition replacement since the total estimated 

number of personnel needed to support the work in the near term is relatively static, with emphasis on 

hiring engineers, safety basis, IT specialists, technicians, and security. Crafts, technicians, and 

administrators typically have lower attrition, while engineers have higher attrition due to high national 

demand. Internal realignment is used in some cases to fill critical vacancies. Y-12 is working with Oak 

Ridge Associated Universities through the Supply Chain Management Center to improve sourcing and 

recruiting capabilities.

Figure F–32. Y-12 workforce projection needs by Common Occupational Classification System1

1 Projections do not include construction craft or Uranium Processing Facility. FY 2024 and FY 2025 headcount is based on actual 

FY 2024 program plans and anticipated funding for FY 2025 scope. Projections for FY 2026 and beyond reflect a stable work scope 

and funding, pending finalization of outyear funding projections.
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F.4 The National Security Site

F.4.1 Nevada National Security Site

F.4.1.1 Mission Overview

The Nevada National Security Site (NNSS), located outside of Las Vegas, Nevada, is the primary location 

within the DOE/NNSA complex where high-hazard experiments with radioactive and other high-hazard 

materials are conducted. It is the only location in the United States that is authorized to conduct 

subcritical experiments with weapons-relevant geometries and quantities of both HE and plutonium.

F.4.1.2 Funding

FY 2024 DOE request – site funding by source 

(total NNSS FY 2024 request = $918 million)

NNSS split for the FY 2024 Weapons Activities

President’s Budget Request ($756 million)

F.4.1.3 Site Capabilities

NNSS supports stockpile stewardship through plutonium experiments in collaboration with LANL, LLNL, 

and SNL; data analyses from those experiments; diagnostic R&D; and reanalysis of legacy underground 

test data.

NNSS’ capabilities and their associated challenges and strategies are described in Table F–8.
Department of Energy/National Nuclear Security Administration | November 2023

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Table F–8. Nevada National Security Site capabilities

Hydrodynamic and Subcritical Experiments at Weapons-Relevant Scales

NNSS performs subcritical experiments at U1a, enabling characterization of early explosion-time hydrodynamic behavior of 

plutonium, plutonium surrogates, and other relevant materials in weapon-relevant geometries. NNSS, LLNL, LANL, and SNL are in 

the process of enhancing U1a to enable well-diagnosed, early- and late-time radiographic and neutron reactivity measurements 

on hydrodynamic tests. These new data will inform efforts to assess the effects of aging and manufacturing processes on stockpile 

weapons.

Challenges Strategies

Increase the tempo, flexibility, and 

sophistication of subcritical experiments.

Current Strategy Being Implemented Future Strategies Needed

• Implement a multi-user U1a 

operating model and an 

integrated, logic-linked framework 

schedule to optimize critical path 

contributors. 

• Invest in U1a, DAF, diagnostics, 

and transportation for future 

subcritical experiments.

• Ensure operational sustainability for 

all necessary radiographic capabilities 

in U1a.

• Enhance efficiencies in experimental 

operations to reduce fielding time and 

the number of experiments required 

for assessment and certification.

• Field next generation diagnostics to 

meet stockpile experimentation 

needs.

Weapons Science Experiments Using High-Hazard Materials

Activities include maturing capabilities in shock and compression experiments; dynamic phase change studies; capture of 

thermodynamic and constitutive properties; platform and source development; and materials diagnostic R&D on the JASPER, the 

ShARC launcher at North Las Vegas, Z at Sandia; and a variety of shock physics platforms at NNSS and the Special Technologies 

Laboratory. JASPER is a two-stage light gas gun for studying the behavior of plutonium and other materials at high pressures, 

temperatures, and strain rates. ShARC is a single-stage gas gun located on the North Las Vegas campus; it is used to support DMPrelated work, test diagnostics, and train diagnostic personnel. Material property data are obtained on a wide variety of national 

security materials of interest in various phases and compositions owing to differences in manufacturing processes, surface 

preparations, and ages.

Challenges Strategies

Breakthroughs in materials science are limited 

by the rate of experimentation, staffing 

constraints, the range of dynamic conditions 

that are available to DOE/NNSA, as well as the 

need for higher-precision diagnostics that can 

measure phase changes, temperature, 

density, and two-dimensional

displacement/velocity-fields at very short 

time scales and very high temperatures, 

pressures, and densities.

Current Strategy Being Implemented Future Strategies Needed

NNSS is seeking efficiencies in 

operations to increase scientific 

throughput at its many shock physics 

platforms. Some of these efficiencies 

are realized through increased 

recruitment activities and 

development of newer, higherprecision diagnostics.

NNSS will leverage site-directed, R&Dinitiated new diagnostics; mature these 

diagnostics; and optimize them for multiplatform use (e.g., hydrodynamic 

experiments, subcritical experiments, 

and JASPER) interferometry, 

diffractometry, radiography, pyrometry, 

and other spectroscopic techniques. 

Device Assembly Facility

DAF supports nuclear weapons experimental capabilities and is one of two facilities in the nuclear security enterprise that allows 

collocation of HE and SNM, including staging of large quantities of SNM in independent buildings and provides the backbone to 

support various missions using those materials in conjunction. For Stockpile Stewardship, the facility’s glovebox, downdraft 

table, and radiography capabilities support assembly of SNM targets for JASPER, as well as SNM and HE packages for subcritical 

experiments at U1a. DAF also hosts the NCERC, a unique national asset. NCERC supports a mix of critical and subcritical 

benchmark quality experiments, detector development, inspector and first responder training, criticality safety training, and

handling of damaged nuclear weapons. NCERC has the largest collection of nuclear critical mass assembly machines in the 

western hemisphere.

Challenges Strategies

As demand for DAF’s wide range of unique 

capabilities grows across DOE/NNSA, space 

and scheduling challenges will grow.

Current Strategy Being Implemented Future Strategies Needed

• Maintain current capabilities.

• Explore options to increase these 

capabilities on a timescale 

complementary to anticipated 

experimental needs (e.g., 

• Enhance efficiencies in experimental 

operations to reduce fielding time and 

number of experiments required for 

assessment and certification.
Department of Energy/National Nuclear Security Administration | November 2023

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enhanced surveillance and 

storage).

• Field next-generation diagnostics to 

meet stockpile experimentation 

needs.

Advanced Experimental Diagnostics and Sensors

NNSS develops the next generation of high-precision, transformational diagnostics for subcritical, hydrodynamic, and dynamic 

materials experiments. Some of these groundbreaking diagnostics include photon Doppler velocimetry, optical ranging (i.e., 

broadband laser ranging), surface imaging, soft X-ray radiography, holography, dynamic pyrometry and emissivity, dynamic X-ray 

diffraction, prompt neutron and X-ray detectors, and advanced radiography sources for subcritical experiments and other 

hydrodynamic platforms.

Challenges Strategies

◼ Advanced diagnostics and sensors provide 

detailed measurements of materials, objects,

and dynamic processes critical to weapon 

operation. Standard diagnostics provide lowerresolution data that are suitable for basic 

inquiries, but not detailed part, process, or 

physics qualification. Continued diagnostic and 

sensor development is critical to addressing 

these limitations.

Current Strategy Being 

Implemented

Future Strategies Needed

NNSS involves nuclear security 

enterprise laboratories in defining 

and prioritizing diagnostic needs 

for future experiments at NNSS 

and other facilities.

• Continue current strategy.

• Develop and field next generation 

diagnostics to meet stockpile 

experimentation needs.

DAF = Device Assembly Facility

DMP = Data Management Plan

HE = high explosive

JASPER = Joint Actinide Shock Physics Experimental Research Facility

NCERC = National Criticality Experiments Research Center

ShARC = Shock Activated Research Collaboration

SNM = special nuclear material

U1a = U1a Complex

Z = Z pulsed power facility

F.4.1.4 Accomplishments

◼ The U1a Complex (U1a) Enhancements Project 10 achieved CD-4 in June of 2022. The U1a

Enhancements Project 20 achieved CD-2/3 in June of 2022. These projects will provide 

infrastructure modifications to the U1a at NNSS to house and field multi-pulse radiography. These

projects include structures, systems, and components necessary for deploying the Enhanced 

Capabilities for Subcritical Experiment (ECSE) Advanced Sources and Detectors (ASD) project’s 

pulsed X-ray radiography equipment. 

◼ ASD achieved CD-2/3 in November 2022. ASD is a major item of equipment that will fill the pulsed 

x-radiography capability gap through developing a multi-pulse linear induction electron 

accelerator. The scope includes design, technical maturation, fabrication, testing, installation, 

commissioning, and readiness execution at U1a.

◼ NNSS completed the refurbishment of the Cygnus radiograph machine, significantly increasing

the lifespan and efficiency of the Cygnus source. This source is approaching 5,000 shots and has 

been the sole U.S. radiographic capability for shock wave studies involving plutonium.

◼ Diagnostic development: NNSS delivered next-generation diagnostic R&D to national laboratories 

to support stockpile experiments. NNSS developed two revolutionary diagnostics capabilities to 

advance the understanding of ejecta and to improve radiographic tools. The first quantitative 

atomic ejecta diagnostic, the Atomic Ejecta source Optical Probe, addresses fundamental 

questions about ejecta sources is and has future fielding application on subcritical experimentclass platforms. NNSS also demonstrated multi-pulse source capabilities and evaluated source 

characteristics of first- and second-pulse size, dose and diode lifetime to capture “first of a kind” 

double-pulse X-ray images from a single anode, providing measurements not previously 

achievable with multi-anode sources for dynamic properties of thin materials. Investments will 

provide control systems, software, detectors, instruments, and camera systems in 2 to 5 years. 
Department of Energy/National Nuclear Security Administration | November 2023

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F.4.1.5 Nevada National Security Site Workforce
Department of Energy/National Nuclear Security Administration | November 2023

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NNSS continues hiring to meet increasing mission needs. Total site headcount increased by 6.1 percent 

in FY 2022, and all Common Occupational Classification System categories experienced an increase in 

headcount with the exception of Scientists. Overall, non-bargaining personnel increased by 

approximately 4.1 percent and bargaining unit personnel (crafts/laborers/operators) increased by 

approximately 12.6 percent in FY 2022. Due to hiring, the average years of service decreased from 

10 percent to 8.84 percent; the 25 and underage category experienced the largest increase at 23 percent. 

The age category of 56–60 experienced a decrease in headcount of 3 percent due to early retirements. 

Of note, a large portion of the security workforce at NNSS is not managed by the M&O contractor and is 

not included in the site headcount or subsequent charts, though the security contractor, SOC LLC, does 

have employees funded by Weapons Activities.

NNSS supports diverse and sustainable education programs focused 

on improving STEM at the elementary school, middle school, high 

school, and collegiate levels. It continues to leverage its academic 

partnerships to familiarize students, interns, and post-docs with the 

site and its mission.

Similar to FY 2021, over half of all terminations occurred within the 0–5 years of service category, as shown 

in Figure F–33, and the majority of these terminations were voluntary. 

Figure F–33. NNSS separations by years of service

Early Engagement in FY 2022

Students: 116

Interns: 2

Post-doctorates: 4
Department of Energy/National Nuclear Security Administration | November 2023

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Advanced Career employees represent the largest workforce contingent at 45 percent of the workforce, 

and that number has remained relatively stable as shown in Figure F–34. Early and Mid-Career employees 

went up slightly from last fiscal year, approximately 1 percent in each category.

Figure F–34. NNSS workforce participation trends by age category and percent advanced career3

As shown in Figure F–35, the number of normal and early retirements remained consistent from last year. 

Voluntary terminations went up by 45 percent from last fiscal year, with the primary reasons being

“Resigned” and “Career Advancement Opportunity.” Involuntary terminations also went up by 83 percent

from FY 2021, primarily due to “Discharge for Cause” and “Failure to Return from a Leave of Absence.”

Approximately 58 percent (80 employees) of bargaining unit employee terminations were due to layoffs. 

Retirements and voluntary turnover went down in FY 2020, which was expected due to the pandemic’s

impacts on the economy and job market. NNSS will continue tracking the reasons for all terminations,

analyzing for trends, and focusing on attracting, retaining, and growing employees, especially in the early 

and mid-career positions.

As Figure F–36 shows, workforce remain consistent across the near-term with minor increases anticipated

for engineers and technicians to support ECSE. FY 2028 reflects a shift from construction to preparing for 

operations in new ECSE test beds.

3 The percentage of advanced-career workers is calculated by taking the ratio of employees over age 50 and total workforce. Age 

50 assumes the minimum age for retirement eligibility.
Department of Energy/National Nuclear Security Administration | November 2023

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Figure F–35. NNSS employee separation trends

Figure F–36. NNSS workforce projection needs by Common Occupational

Classification System4

4 FY 2024–FY 2027 projections were updated to include the Protective Force, which was previously excluded since it was not part 

of the M&O contract. Protective Force became part of the M&O contract in April 2023.
Department of Energy/National Nuclear Security Administration | November 2023

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Appendix G

Glossary

abnormal environment, abnormal and hostile environment, abnormal conditions—An environment, as 

defined in a weapon’s stockpile-to-target sequence and military characteristics, in which the weapon is 

not expected to retain full operational reliability, or an environment that is not expected to occur during 

nuclear explosive operations and associated activities. 

additive manufacturing—A manufacturing technique that builds objects layer by layer, according to 

precise design specifications, compared to a traditional manufacturing technique in which objects are 

carved out of a larger block of material or cast in molds and dies. 

advanced manufacturing—Modern technologies necessary to enhance secure manufacturing capabilities 

and provide timely support for critical needs of the stockpile.

alteration—A material change to, or a prescribed inspection of, a nuclear weapon or major assembly that 

does not alter its operational capability, yet is sufficiently important to the user regarding assembly,

maintenance, storage, or test operations to require controlled application and identification. 

annual assessment—The authoritative method to evaluate the safety, reliability, performance, and 

military effectiveness of the stockpile by subject matter experts based upon new and legacy data, 

surveillance, and modeling and simulation. It is a principal factor in the Nation’s ability to maintain a 

credible deterrent without nuclear explosive testing. The Directors of the three national security 

laboratories complete annual assessments of the stockpile, and the Commander of the U.S. Strategic 

Command provides a separate assessment of military effectiveness. The assessments also determine

whether underground nuclear explosive testing must be conducted to resolve any issues. The Secretaries 

of Energy and Defense submit the reports unaltered to the President, along with any conclusions they

deem appropriate.

arming, fuzing, and firing—The electronic and mechanical functions that ensure a nuclear weapon does

not operate when not intended during any part of its manufacture and lifetime, but also ensure the

weapon will operate correctly when a unique signal to do so is properly activated. 

artificial intelligence—Computer systems able to perform tasks intelligently, similar to humans, such as 

visual perception, speech recognition, decision-making, and translating between languages.

B61—An air-delivered thermonuclear gravity bomb.

B61-12 Life Extension Program (LEP)—An LEP to consolidate four families of the B61 bomb in the active 

stockpile into one and improve the safety and security of the oldest weapon system in the U.S. arsenal.

calciner—A dry thermal treatment process to convert low-equity enriched uranium liquids to a dry stable 

form for storage. 
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certification—The process whereby all available information on the performance of a weapon system is 

considered and the laboratory directors responsible for that system certify, before the weapon enters the 

stockpile, that it will meet, with noted exceptions, the military characteristics within the environments 

defined by the stockpile-to-target sequence.

component—An assembly or combination of parts, subassemblies, and assemblies mounted together 

during manufacture, assembly, maintenance, or rebuild. In a system engineering product hierarchy, the 

component is the lowest level of shippable and storable entities, which may be raw material, procured 

parts, or manufactured items.

conventional high explosive—A high explosive that detonates when given sufficient stimulus by a 

high-pressure shock. Stimuli from severe accident environments involving impact, fire, or electrical 

discharge may also detonate a conventional high explosive. See also “insensitive high explosive.”

critical decision (CD)—The five levels a U.S. Department of Energy project typically progresses through, 

which serve as major milestones approved by the Chief Executive for Project Management. Each CD marks 

an authorization to increase the commitment of resources and requires successful completion of the 

preceding phase. These five phases are CD-0, Approve Mission Need; CD-1, Approve Alternative Selection 

and Cost Range; CD-2, Approve Performance Baseline; CD-3, Approve Start of Construction/Execution; 

CD-4, Approve Start of Operations or Project Completion.

cybersecurity—The physical, technical, administrative, and management controls for providing the 

required and appropriate levels of protections of information and information assets against unauthorized 

disclosure, transfer, modification, or destruction, whether accidental or intentional. Cybersecurity also 

ensures the required and appropriate level of confidentiality, integrity, availability, and accountability for 

the information stored, processed, or transmitted on electronic systems and networks.

depleted uranium—Uranium from which most of the fissile isotope uranium-235 has been removed. It is 

required for nuclear component production to maintain and modernize the stockpile through life 

extension, modification, and limited life component exchange programs. 

design agency—Any of the management and operating partners in the nuclear security enterprise who 

serve as lead designers for nuclear weapon components or systems, usually one of the three national 

security laboratories. 

design life—The length of time, starting from the date of manufacture, during which a nuclear weapon is 

designed to meet its stated military requirements.

dismantlement and disposition—Disassembling retired weapons into major components that are then 

assigned for reuse, storage, surveillance, or disposal.

downblending—Processing highly enriched uranium into a uranium byproduct that contains less than 

20 percent uranium-235.

down-select—The process of narrowing the range of design options during the Phase X/6.X Process,

culminating in a final design (normally exercised when moving from Phase 1/Phase 6.1 to 

Phase 2/Phase 6.2, from Phase 2/Phase 6.2 to Phase 2A/Phase 6.2A, and from Phase 2A/6.2A to 

Phase 3/Phase 6.3). Down-selecting involves analysis of the option’s ability to meet military 

requirements, and assessment of schedule, cost, material, and production impacts. 
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electrorefining—An electrochemical metal purification system designed to provide a replacement 

capability for the current metal purification process.

enriched uranium—Uranium that contains higher concentrations of the fissile uranium-235 isotope than 

natural uranium. It is required at varied enrichment levels for national security and medical isotope 

production. 

exascale computing—Computing systems capable of at least one exaFLOPS, or one billion billion

calculations per second. Such capacity represents a thousand-fold increase over the first petascale 

computer that came into operation in 2008. See also “floating point operations per second (FLOPS).”

first production unit—The first system, subsystem, or component manufactured and accepted by the 

National Nuclear Security Administration (NNSA) as verifiably meeting all applicable quality and 

qualification requirements. The first production unit for a weapon is a production milestone. For 

milestone completion, two events must occur: (1) the Department of Defense or the Nuclear Weapons 

Council accepts the design and (2) the Department of Energy/NNSA verifies that the first produced 

weapon meets the design specifications. 

fiscal year—The Federal budget and funding year that starts on October 1 and goes to the following 

September 30.

fission—The process whereby the nucleus of a particular heavy element splits into (generally) two nuclei 

of lighter elements, with the release of substantial energy.

floating point operations per second (FLOPS)—The number of arithmetic operations performed on real 

numbers in a second; used as a measure of the performance of a computer system.

fusion—The process whereby the nuclei of two light elements, especially the isotopes of hydrogen 

(i.e., deuterium and tritium), combine to form the nucleus of a heavier element with the release of 

substantial energy and a high-energy neutron.

Future Years Nuclear Security Program—A detailed description of the program elements (and associated 

projects and activities) for the fiscal year for which the annual budget is submitted and the four succeeding 

fiscal years.

gas transfer system—A warhead component that enables tritium, a radioactive isotope of hydrogen, to 

boost the yield of a nuclear weapon. 

high energy density physics—The physics of matter and radiation at very high energy densities, i.e.,

extreme temperatures and pressures. 

high explosives (HE)—Materials that detonate, with the chemical reaction components propagating at 

supersonic speeds. HE are used in the main charge of a weapon primary to compress the fissile material 

and initiate the chain of events leading to nuclear yield. See also “conventional high explosive” and 

“insensitive high explosive.”

high performance computing—The use of supercomputers and parallel processing techniques with 

multiple computers to perform computational tasks. 

ignition—The point at which a nuclear fusion reaction becomes self-sustaining—that is, more energy is 

produced and retained in the fusion target than the energy used to initiate the nuclear reaction.
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information technology—The equipment or interconnected system or subsystem of equipment used in 

the automatic acquisition, storage, manipulation, management, movement, control, display, switching, 

interchange, transmission, or reception of data or information. Information technology includes 

computers, ancillary equipment, software, firmware, and related procedures, services, and resources. 

infrastructure—For the purposes and scope of the Stockpile Stewardship and Management Plan, 

infrastructure refers to the comprehensive inventory of facilities, structures, utilities, equipment, and 

other physical assets required to operate the national security enterprise in service to its national security 

missions. 

insensitive high explosive—A high explosive substance that is so insensitive that the probability of 

accidental initiation or transition from burning to detonation is negligible.

integrated design code (IDC)—A simulation code containing multiple physics and engineering models that 

have been validated experimentally and computationally. An IDC is used to simulate, understand, and 

predict the behavior of nuclear and non-nuclear components and nuclear weapons under normal, 

abnormal, and hostile conditions.

joint test assembly—(1) An electronic unit that contains sensors and instrumentation that monitor 

weapon hardware performance during flight tests to ensure that the weapon components will function 

as designed. (2) A National Nuclear Security Administration (NNSA)-developed configuration, based on 

NNSA-Department of Defense requirements, for use in the flight test program.

life extension program (LEP)—A program that refurbishes warheads of a specific weapon type to extend 

the service life of a weapon. LEPs are designed to extend the life of a warhead by 20 to 30 years, while 

increasing safety and security.

lifecycle—The series of stages through which a component, system, or weapon passes from initial 

development until it is consumed, disposed of, or altered to extend its lifetime.

lightning arrestor connector—Advanced interconnected nuclear safety devices designed to limit voltage 

during lightning strikes and in other extreme, high-voltage, high-temperature environments.

limited life component—A weapon component or subsystem whose performance degrades with age and 

must be periodically replaced. Examples are gas transfer systems, power sources, and neutron 

generators.

line-item project—A distinct design, construction, betterment and/or fabrication of real property for 

which Congress will be requested to authorize and appropriate specific funds. 

lithium—A soft, lightweight, silvery-white alkali metal (symbol: Li) used as a target element in nuclear 

weapons. Lithium reacts with a neutron to produce tritium. It is considered a strategic material in nuclear 

weapon manufacture. 

machine learning—A type of artificial intelligence characterized by computer algorithms that improve 

automatically through experience, so the computer learns without being explicitly programmed.

Manufacturing Readiness Level (MRL)—A means of communicating the degree to which a component or 

subsystem is ready to be produced. MRLs represent many attributes of a manufacturing system 

(e.g., people, manufacturing capability, facilities, conduct of operations, and tooling). There are nine 

MRLs, with the lowest being product development and the highest being steady-state production.
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military characteristics—Required characteristics of a nuclear weapon upon which depend its ability to 

perform desired military functions, including physical and operational characteristics, but not technical 

design characteristics. 

modernization—The changes to nuclear weapons or infrastructure due to aging, unavailability of 

replacement parts, or the need to enhance safety, security, and operational design features. In the 

context of the physical infrastructure that support the nuclear security missions, modernization refers to 

recapitalization and refurbishment investments to restore and refresh aging facilities, structures, utilities, 

equipment, and other physical assets to a state that fully supports mission functionality and underpins 

key Weapons Activity capabilities into the future.

modification (Mod)—A program that changes a weapon’s operational capabilities. A Mod may enhance 

the margin against failure, increase safety, improve security, replace limited life components, and/or 

address identified defects and component obsolescence. 

national security laboratories—Los Alamos National Laboratory, Sandia National Laboratories, and

Lawrence Livermore National Laboratory. These laboratories guide research and development on behalf 

of Department of Energy/National Nuclear Security Administration Mission needs and address science 

and engineering challenges, from basic science questions through weapons design and production. They 

also support nuclear counterterrorism and counterproliferation.

network—In relation to information technology and cybersecurity, a network is composed of a 

communications medium responsible for the transfer of information and all components attached to that 

medium.

network monitoring—The use of a system that constantly monitors a computer network, providing

vulnerability management and policy compliance tools; operating system, database, and application logs; 

and compilation of external threat data. A key focus is monitoring and managing user and service 

privileges, directory services, and other system configuration changes. Network monitoring also provides

log auditing and review of incident responses.

non-nuclear components—The parts or assemblies designed for use in nuclear weapons or in nuclear 

weapons training that do not contain special nuclear material; such components (e.g., radiation-hardened 

electronic circuits or arming, fuzing, and firing components) are not available commercially.

nuclear explosive package—An assembly containing fissionable and/or fusionable materials, as well as the 

main charge high-explosive parts or propellants capable of producing a nuclear detonation. 

nuclear forensics—The investigation of nuclear materials to find evidence for the source, trafficking, and 

enrichment of the material. 

nuclear security enterprise—The physical infrastructure, technology, and workforce at the national 

security laboratories, the nuclear weapons production sites, and the Nevada National Security Site, that 

sustain the research, development, production, and dismantlement capabilities needed to support the 

nuclear weapons stockpile. 
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Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page G-6

nuclear stockpile—The nuclear stockpile includes both active and inactive warheads. Active warheads 

include strategic and non-strategic weapons maintained in an operational, ready-for-use configuration, 

warheads that must be ready for possible deployment within a short timeframe, and logistics spares. They 

have tritium bottles and other limited life components installed. Inactive warheads are maintained at a 

depot in a non-operational status, and have their tritium bottles removed. A retired warhead is removed 

from its delivery platform, is not functional, and is not considered part of the nuclear stockpile. Warheads 

awaiting dismantlement constitute a significant fraction of the total warhead population. A dismantled 

warhead is a warhead reduced to its component parts.

Nuclear Weapons Council—The joint Department of Energy/Defense of Defense Council composed of 

senior officials from both Departments who recommend the stockpile options and research priorities that 

shape national policies and budgets to develop, produce, surveil, and retire nuclear warheads and weapon 

delivery platforms, and who consider the safety, security, and control issues for existing and proposed 

weapons programs.

nuclear weapons stockpile—Both active and inactive nuclear warheads. Active warheads include strategic 

and non-strategic weapons maintained in an operational, ready-for-use configuration, ready for possible 

deployment within a short timeframe, with logistics spares. 

neutron generator—A limited life component that provides neutrons at specific times and rates to initiate 

weapon function. 

Other Program Money—Funding that is found outside of a life extension program (LEP) funding line (in 

other program lines), but is directly (uniquely) attributed to an LEP. Such funding would not be needed 

were it not for the LEP, although the activity or effort might still be done at some future point along a 

different timeline.

out-years—The years that follow the 5-year period of the Future Years Nuclear Security Program. 

Phase X/Phase 6.X Process—The Phase X process provides a common framework to conduct and manage 

activities for new production and refurbishments of nuclear weapons. Stockpile refurbishment activities 

are divided into sub-elements of Phase 6, denoted by Phase 6.X, that correspond to Phases 1 through 6

of the nuclear weapons lifecycle. The Phase 6.X Process provides a time and organizational framework to 

manage the existing nuclear weapon systems that are undergoing evaluation and implementation of 

refurbishment options to extend their stockpile life or enhance system capabilities. 

physical security—The physical or technical methods that protect personnel; prevent or detect 

unauthorized access to facilities, material, and documents; protect against espionage, sabotage, damage, 

and theft; and respond to any such acts that occur.

pit—The critical core component in the primary of a nuclear weapon that contains fissile material.

power source—Compact, specialized, limited-life components that fulfill power requirements for current

and future planned nuclear weapons and life-extended warheads. 

primary—The first stage of a two-stage nuclear weapon.

production sites—Savannah River Site, Y-12 National Security Complex, Kansas City National Security 

Campus, and Pantex Plant sites produce most of the designed weapon components and assemble 

weapons. (Production sites are sometimes also referred to as production facilities, plants, and agencies.)
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page G-7

programmatic infrastructure—Specialized experimental facilities, computers, diagnostic instruments, 

processes, and capabilities that allow the nuclear security enterprise to carry out research, testing, 

production, sustainment, and other direct programmatic activities to meet national security missions. 

qualification—The process of ensuring that design, product, and all associated processes are capable of 

meeting customer requirements. Qualification authorizes the listed items for an intended use (i.e., War 

Reserve, Training, Evaluation, etc.), and it generally includes national security laboratory (design) review 

of production and inspection processes. Qualified items are reviewed for possible requalification after a 

significant process change or if production is inactive for 12 months.

recapitalization—In the context of physical infrastructure that supports nuclear security missions, 

recapitalization refers to investments in existing facilities, structures, utilities, equipment, and other 

assets that upgrade, renew, or otherwise improve and extend the usable life of the asset.

reservoir—A vessel containing deuterium and tritium that permits its transfer as a gas in a nuclear 

weapon.

resilience—The ability of the nuclear security enterprise to recover from an insult or stress in a sufficiently 

timely manner to not compromise the national deterrence mission.

responsive—The capability and capacity of the nuclear security enterprise to respond in a timely manner 

to technical and/or geopolitical surprises (and the requirements they generate).

Safeguards Transporter—A highly specialized trailer designed to safeguard nuclear weapons and special 

nuclear materials while in transit.

secondary—The second stage of a two-stage nuclear weapon that provides additional energy release in 

the form of fusion, and is activated by energy from the primary.

security—An integrated system of activities, systems, programs, facilities, and policies to protect classified 

matter, unclassified controlled information, nuclear materials, nuclear weapons, nuclear weapon 

components, and Department of Energy’s and its contractors’ facilities, property, and equipment.

security system—The combination of personnel, equipment, hardware and software, structures, plans 

and procedures, etc., used to protect safeguards and security interests.

service life—The duration of time that a nuclear weapon is maintained in the stockpile from Phase 5/6.5 

(First Production) to Phase 7 (Retirement, Dismantlement, and Disposition). Service life can include the 

terms “stockpile life,” “deployed life,” and “useful life.” 

significant finding investigation—A formal investigation by a committee, chaired by an employee of a 

national security laboratory, to determine the cause and impact of a reported anomaly and to recommend 

corrective actions as appropriate.

special nuclear material (SNM)—Plutonium, uranium-233, or uranium enriched in the isotopes 

uranium-233 or uranium-235. The Nuclear Regulatory Commission defines three categories of quantities 

of SNM according to the risk and potential for its use in the creation of a fissile explosive. Category I is 

the category of the greatest quantity and associated risk; Category II is moderate; Category III is the 

lowest.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page G-8

stockpile sustainment—The activities responsible for the day-to-day health of the stockpile, including

surveillance, annual assessments, and routine maintenance, to ensure weapons remain safe, secure, and 

reliable for their projected life cycle. 

Stockpile System—Weapons systems that are currently in the stockpile (B61-3/4/10/11/12, B83, W80-1, 

W88-0 [and Alt 370], W87-0, W76-0/1/2, W78).

stockpile-to-target sequence—The order of events involved in removing a nuclear weapon from storage 

and assembling, testing, transporting, and delivering it to the target. The term also refers to a document 

that defines the logistical and employment concepts and related physical environments involved in 

delivering a nuclear weapon to a target.

subcritical experiment—An experiment specifically designed to obtain data on nuclear weapons for which 

less than a critical mass of fissionable material is present and, hence, no self-sustaining nuclear fission 

chain reaction can occur, consistent with the Comprehensive Nuclear Test Ban Treaty.

surety—The assurance that a nuclear weapon will operate safely, securely, and reliably if deliberately 

activated and that no accidents, incidents, or unauthorized detonations will occur. Factors contributing 

to that assurance include model validation for weapon performance based on experiments and 

simulations, material (e.g., military equipment and supplies), personnel, and execution of procedures.

surveillance—Activities that provide data for evaluation of the stockpile, giving confidence in the Nation’s 

deterrent by demonstrating mission readiness and assessment of safety, security, and reliability

standards. These activities may include laboratory and flight testing of systems, subsystems, and 

components (including those of weapons in the existing stockpile, newly produced weapons, or weapons 

being disassembled); inspection for unexpected wear or signs of material aging; and destructive or 

nondestructive testing.

sustainment—A National Nuclear Security Administration program to modify and maintain a set of nuclear 

weapon systems (see “stockpile sustainment”). In the context of physical infrastructure that supports the 

nuclear security missions, sustainment refers to the set of activities over an asset’s lifetime that provide 

for maintaining, operating, refurbishing, upgrading, and recapitalizing that asset until retirement and 

disposition. 

technology maturation—Advancing laboratory-developed technology to the point where it can be 

adopted and used by U.S. industry. 

test readiness—The preparedness to conduct underground nuclear explosive testing if required to ensure 

the safety and effectiveness of the stockpile, or if directed by the President for policy reasons. 

tritium—A radioactive isotope of hydrogen whose nucleus contains two neutrons and one proton. It is 

produced in nuclear reactors by the action of neutrons on lithium nuclei.

uranium—A naturally occurring radioactive, metallic element (symbol: U) that is found in the earth as a 

mineral ore. It has three primary isotopes: uranium-238, -235, and -234. It is a strategic material, with 

several uses related to nuclear weapons and therefore is critical to national security.

uranium enrichment—The process of increasing the concentration of the uranium-235 isotope in a sample 

of uranium by separating it from uranium-238.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page G-9

Verification and validation—Independent procedures that are used together for checking that a product, 

service, or system meets requirements and specifications, and that it fulfills its intended purpose. For 

example, in the context of software testing, verification provides evidence of the correctness of computer 

codes in solving pertinent equations, while validation assesses the adequacy of the physical models used 

to represent reality. Verification and validation is also applied to nuclear weapons to ensure that they 

fulfill their intended function with sufficient precision to meet military and other specifications.

W76-1 LEP—A life extension program for the W76 submarine-launched ballistic missile warhead, 

delivered by a Navy Trident II.

W78—An intercontinental ballistic missile warhead, delivered by an Air Force Minute Man III LGM-30.

W80-4 LEP—A life extension program for the W80 warhead aboard a cruise missile, delivered by the 

Air Force B-52 bomber and future launch platforms.

W88—A submarine-launched ballistic missile warhead, delivered by a Navy Trident II.

W88 Alteration (Alt) 370—An Alt of the W88 warhead to replace the arming, fuzing, and firing components

and to refresh the conventional high explosive main charge.

W87-1—An intercontinental ballistic missile warhead designed to replace the W78 and support the 

Air Force’s ground-based strategic deterrent missile system planned to replace the Minuteman III.

warhead—The part of a missile, projectile, torpedo, rocket, or other munition that contains either the 

nuclear or thermonuclear system intended to inflict damage.

War Reserve—Nuclear weapons and nuclear weapon material intended for use in the event of war.

weapon—(1) Warhead and its delivery system (missile, etc). (2) A gravity bomb (e.g., B61-12) can be 

referred to as a weapon even when separate from the aircraft carrying it.

Weapons Activities—Sustaining, modernizing, and dismantling nuclear weapons; maintaining and 

modernizing production operations; and optimizing the scientific tools underpinning these efforts. The 

term also refers to the portion of the National Nuclear Security Administration budget covering these 

activities. 

Weapon System—The combination of the National Nuclear Security Administration nuclear weapon and 

ancillary equipment and the Department of Defense carriers and ancillary items including aircraft, 

missiles, ships, submarines, launchers, hardware, and software.
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page H-1

Appendix H

Acronyms and Abbreviations

ACCESS Apprenticeships for Complete and Committed Employment for Specialized Skills

ACRR Annular Core Research Reactor

Alt Alteration

AoA Analysis of Alternatives

ASC Advanced Simulation and Computing

ASD Advanced Sources and Detectors

BCR Baseline Cost Report

CBI Capabilities-Based Investments

CD Critical Decision

CEAG Cost Estimating and Analysis Group

CFIUS Committee on Foreign Investment in the United States

COVID-19 Coronavirus Disease 2019

CREST Combined Radiation Environments for Survivability Testing

CSTART Center for Security Technology, Analysis, Response, and Testing

CTCP Office of Counterterrorism and Counterproliferation

CUAS counter unmanned aircraft system

D&I disassembly and inspection

DARHT Dual-Axis Radiographic Hydrodynamic Test

DM deferred maintenance

DNS Defense Nuclear Security

DoD Department of Defense

DOE Department of Energy

DU depleted uranium

DUE domestic uranium enrichment

DUF4 depleted uranium tetrafluoride

DUF6 depleted uranium hexafluoride

ECI Exascale Computing Initiative

ECP Exascale Computing Project

ECSE Enhanced Capabilities for Subcritical Experiments

EMC Energetic Materials Characterization

EMC2Enhanced Minor Construction and Commercial Practices

FA Federal Agent

FFRDC Federally Funded Research and Development Center

FITARA Federal IT Acquisition Reform Act

FY fiscal year

FYNSP Future Years Nuclear Security Program

G2 Generation 2

GAO Government Accountability Office

GTS gas transfer system

HE high explosives
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page H-2

HE&E high explosives and energetics

HESFP High Explosive Synthesis, Formulation, and Production Facility

HED high energy density

HESE high explosives science and engineering

HEU highly enriched uranium

HPC high performance computing

HPDU high purity depleted uranium

ICF inertial confinement fusion

IDA Institute for Defense Analyses

IDC integrated design code

IMI Infrastructure Modernization Initiative

IT information technology

JASPER Joint Actinide Shock Physics Experimental Research

JTA joint test assembly

KCNExT Kansas City Non-Nuclear Expansion Transformation

KCNSC Kansas City National Security Campus

KC STEP Kansas City Short-Term Expansion Plan

kV kilovolt

LAMP LANSCE Modernization Project

LANL Los Alamos National Laboratory

LANSCE Los Alamos Neutron Science Center

LAP4 Los Alamos Plutonium Pit Production Project

LEP Life Extension Program

LEU low-enriched uranium

LLC limited life component

LLNL Lawrence Livermore National Laboratory

LRSO Long Range Standoff

M3 material management and minimization

M&O management and operating

MESA Microsystems Engineering, Science and Applications

MFFF Mixed Oxide Fuel Fabrication Facility

MGT Mobile Guardian Transporter

MIE major item of equipment

MJ megajoules

Mod Modification

MRL manufacturing readiness level

MSIPP Minority Serving Institution Partnership Program

NEA Nuclear Enterprise Assurance

NEST Nuclear Emergency Support Team

NIB nuclear security enterprise industrial base

NIF National Ignition Facility

NNSA National Nuclear Security Administration

NNSS Nevada National Security Site

NPAC nonproliferation and arms control

NRC Nuclear Regulatory Commission

OCIO Office of the Chief Information Officer

OMB Office of Management and Budget

Omega Omega Laser Facility
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page H-3

OT operational technology

Pantex Pantex Plant

PF-4 Plutonium Facility

PPBE planning, programming, budget, and evaluation 

ppy pits per year

R&D research and development

RACR Radiography/Assembly Capability Replacement

RPV replacement plant value

RTG radioisotope thermoelectric generators

SAR Selected Acquisition Report

SFI significant finding investigation

SGT Safeguards Transporter

SIRP Security Infrastructure Revitalization Program

SME subject matter expert

SNL Sandia National Laboratories

SNM special nuclear material

SRNS Savannah River Nuclear Solutions

SRP Stockpile Responsiveness Program

SRPPF Savannah River Plutonium Processing Facility

SRS Savannah River Site

SRTE Savannah River Tritium Enterprise

SRT&E Stockpile Research, Technology, and Engineering

SSMP Stockpile Stewardship and Management Plan

STA Secure Transportation Asset

STAR Standardized Acquisition and Recapitalization

STEM science, technology, engineering, math

STS stockpile-to-target sequence

TA Technical Area

TA2 Test Article 2

TEPP Tribal Education Partnership Program

TFF Tritium Finishing Facility

TMP Tritium Modernization Program

TPBAR tritium-producing burnable absorber rod

TRL technology readiness level

TSRH Trusted and Strategic Radiation-Hardened

TVA Tennessee Valley Authority

U1a U1a Complex

UAS uncrewed aircraft system

UCEP U1a Complex Enhancements Project

USSTRATCOM U.S. Strategic Command

VIM Vacuum Induction Melt

VAR Vacuum Arc Remelt

WBN Watts Bar nuclear reactors

WDCR Weapon Design and Cost Report

WDD Weapons Dismantlement and Disposition

WIP Weapon Intern Program

WR War Reserve

WTMM weapon technology and manufacturing maturation
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page H-4

Y-12 Y-12 National Security Complex

Z Z pulsed power facility
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page I-1

Appendix I

List of Figures and Tables

List of Figures

Figure 1–1. The DOE/NNSA nuclear security enterprise ........................................................................................1-4

Figure 1–2. Integrated stockpile model..................................................................................................................1-8

Figure 1–3. Timeline for key infrastructure and capability investments for future warheads.............................1-10

Figure 2–1. Stockpile Management major subprograms .......................................................................................2-2

Figure 2–2. DOE/NNSA Warhead Activities............................................................................................................2-8

Figure 2–3. Phase X and Phase 6.X Processes.........................................................................................................2-9

Figure 3–1. Potential production process with new technology insertion...........................................................3-13

Figure 3–2. Count of equipment by useful life consumed....................................................................................3-29

Figure 4–1. Stewardship Capability Delivery Schedule – the four key focus areas needed to address 

mission delivery ...................................................................................................................................4-3

Figure 4–2. Weapon assessments rely on many sources of information from Stockpile Research, 

Technology, and Engineering...............................................................................................................4-4

Figure 4–3. Subprograms in Science, Research, Technology, and Engineering......................................................4-6

Figure 5–1. Defense Nuclear Security Program elements (excludes construction)................................................5-7

Figure 5–2. Infrastructure and Weapons Program expansion..............................................................................5-10

Figure 5–3. Information Technology and Cybersecurity major elements and initiatives.....................................5-12

Figure 5–4. Ongoing and recently completed information technology and cybersecurity projects....................5-14

Figure 6–1. DOE/NNSA infrastructure size and scope............................................................................................6-2

Figure 6–2. Asset management lifecycle ................................................................................................................6-3

Figure 6–3. Asset condition by replacement plant value percentage ....................................................................6-4

Figure 6–4. Critical Decision process......................................................................................................................6-7

Figure 6–5. Historical and projected average age of all DOE/NNSA facilities.......................................................6-10

Figure 6–6. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Production Modernization.................................................................................................................6-11

Figure 6–7. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Stockpile Research, Technology, and Engineering.............................................................................6-17

Figure 6–8. 25-year programmatic line-item schedule for ongoing and proposed projects under 

Defense Nuclear Security...................................................................................................................6-20

Figure 6–9. 25-year mission-enabling line-item schedule....................................................................................6-21

Figure 7–1. The DOE/NNSA nuclear security enterprise ........................................................................................7-4

Figure 7–2. M&O and Federal share of total Weapons Activities workforce.........................................................7-4

Figure 7–3. Turnover rate trends............................................................................................................................7-6
Department of Energy/National Nuclear Security Administration | November 2023

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Figure 7–4. M&O Workforce breakdown by Common Occupational Code ...........................................................7-8

Figure 7–5. Workforce breakdown of national security laboratories, the Nevada National Security Site, 

and weapons production facilities by age group.................................................................................7-8

Figure 7–6. Workforce breakdown of national security laboratories, the Nevada National Security Site, 

and weapons production facilities by years of service ........................................................................7-9

Figure 7–7. Total M&O separations by age group................................................................................................7-10

Figure 7–8. Total M&O separations by years of service.......................................................................................7-10

Figure 7–9. NNSA Graduate Fellowship Program Class of 2021–2022 Post-Fellowship Employment.................7-14

Figure 8–1. Fiscal year 2024 President’s Budget Request for Stockpile Management ..........................................8-4

Figure 8–2. Key milestones for Stockpile Management.........................................................................................8-6

Figure 8–3. Fiscal year 2024 President’s Budget Request for Production Modernization .....................................8-7

Figure 8–4. Key milestones for Primary Capability Modernization ......................................................................8-10

Figure 8–5. Key milestones for Secondary Capability Modernization..................................................................8-11

Figure 8–6. Key milestones for Tritium Modernization and Domestic Uranium Enrichment ..............................8-12

Figure 8–7. Key milestones for Non-Nuclear Capability Modernization ..............................................................8-12

Figure 8–8. Fiscal year 2024 President’s Budget Request for Stockpile Research, Technology, 

and Engineering .................................................................................................................................8-13

Figure 8–9. Key milestones for Stockpile Research, Technology, and Engineering..............................................8-16

Figure 8–10. Fiscal year 2024 President’s Budget Request for Infrastructure and Operations .............................8-17

Figure 8–11. Fiscal year 2024 President’s Budget Request for Other Weapons Activities.....................................8-21

Figure 8–12. Key milestones for Secure Transportation Asset...............................................................................8-22

Figure 8–13. Key milestones for Defense Nuclear Security....................................................................................8-23

Figure 8–14. Key milestones for Information Technology and Cybersecurity........................................................8-24

Figure 8–15. Cost estimates across the Phase X/6.X Process.................................................................................8-25

Figure 8–16. B61-12 Life Extension Program cost from fiscal year 2009 to completion........................................8-28

Figure 8–17. W88 Alteration 370 Program (with conventional high explosive refresh) from 

fiscal year 2013 to completion ..........................................................................................................8-29

Figure 8–18. W80-4 Life Extension Program cost from fiscal year 2015 to completion ........................................8-30

Figure 8–19. W87-1 Modification Program cost from fiscal year 2019 to completion ..........................................8-31

Figure 8–20. W93 Modification Program cost from fiscal year 2021 to completion..............................................8-32

Figure 8–21. Total projected Stockpile Major Modernization costs for fiscal years 2022–2047 with 

high and low estimates (then-year dollars).......................................................................................8-34

Figure 8–22. Projected out-year budget estimates for DOE/NNSA Weapons Activities in then-year dollars........8-38

Figure C–1. Overview of the DOE/NNSA Exascale Computing Initiative ............................................................... C-1

Figure C–2. Exascale Computing Project integrated project team........................................................................ C-4

Figure E–1. The nuclear security enterprise industrial base framework................................................................E-1

Figure F–1. The DOE/NNSA nuclear security enterprise ........................................................................................F-1

Figure F–2. Federal workforce employee separation trends .................................................................................F-4

Figure F–3. Federal workforce separations by years of service .............................................................................F-5

Figure F–4. Federal workforce trend over time by stage of career........................................................................F-5

Figure F–5. LLNL separations by years of service .................................................................................................F-12

Figure F–6. LLNL workforce participation trends by age category and percent advanced career.......................F-13

Figure F–7. LLNL employee separation trends.....................................................................................................F-13

Figure F–8. LLNL workforce projection needs by Common Occupational Classification System.........................F-14

Figure F–9. LANL separations by years of service.................................................................................................F-23
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page I-3

Figure F–10. LANL workforce trends by career category and percent advanced career .......................................F-24

Figure F–11. LANL employee separation trends.....................................................................................................F-25

Figure F–12. LANL workforce projection needs by Common Occupational Classification System ........................F-25

Figure F–13. SNL separations by years of service...................................................................................................F-35

Figure F–14. SNL workforce participation trends by age career stage and percent advanced career...................F-36

Figure F–15. SNL employee separation trends.......................................................................................................F-37

Figure F–16. SNL workforce projection needs by Common Occupational Classification System...........................F-37

Figure F–17. KCNSC separations by years of service ..............................................................................................F-44

Figure F–18. KCNSC workforce participation trends by age category and percent advanced career....................F-45

Figure F–19. KCNSC employee separation trends..................................................................................................F-45

Figure F–20. KCNSC workforce projection needs by Common Occupational Classification System......................F-46

Figure F–21. Pantex separations by years of service..............................................................................................F-51

Figure F–22. Pantex workforce participation trends by age category and percent advanced career....................F-51

Figure F–23. Pantex employee separation trends..................................................................................................F-52

Figure F–24. Pantex workforce projection needs by Common Occupational Classification System......................F-53

Figure F–25. SRTE and Plutonium separations by years of service ........................................................................F-58

Figure F–26. SRTE and Plutonium trends by career stage and percent advanced career......................................F-59

Figure F–27. SRTE and Plutonium employee separation trends ............................................................................F-59

Figure F–28. SRTE and Plutonium workforce projection needs by Common Occupational Classification 

System ...............................................................................................................................................F-60

Figure F–29. Y-12 separations by years of service..................................................................................................F-66

Figure F–30. Y-12 workforce participation trends by age category and percent advanced career .......................F-67

Figure F–31. Y-12 employee separation trends......................................................................................................F-67

Figure F–32. Y-12 workforce projection needs by Common Occupational Classification System .........................F-68

Figure F–33. NNSS separations by years of service ................................................................................................F-73

Figure F–34. NNSS workforce participation trends by age category and percent advanced career......................F-74

Figure F–35. NNSS employee separation trends....................................................................................................F-75

Figure F–36. NNSS workforce projection needs by Common Occupational Classification System........................F-75
Department of Energy/National Nuclear Security Administration | November 2023

Fiscal Year 2024 Stockpile Stewardship and Management Plan | Page I-4

List of Tables

Table 1–1. Current U.S. nuclear weapons and associated delivery systems........................................................ 1-5

Table 3–1. Summary of Plutonium Modernization challenges and strategies......................................................3-5

Table 3–2. Summary of High Explosives and Energetics Modernization challenges and strategies.....................3-7

Table 3–3. Summary of Uranium Modernization challenges and strategies ......................................................3-11

Table 3–4. Summary of Depleted Uranium Modernization challenges and strategies.......................................3-15

Table 3–5. Summary of Lithium Modernization challenges and strategies ........................................................3-18

Table 3–6. Summary of Tritium Modernization challenges and strategies.........................................................3-22

Table 3–7. Summary of Domestic Uranium Enrichment challenges and strategies............................................3-24

Table 3–8. Summary of Non-Nuclear Capability Modernization challenges and strategies...............................3-27

Table 3–9. Summary of Capabilities-Based Investments challenges and strategies...........................................3-29

Table 4–1. Summary of Assessment Science challenges and strategies...............................................................4-9

Table 4–2. Summary of Engineering and Integrated Assessments challenges and strategies............................4-11

Table 4–3. Summary of Inertial Confinement Fusion challenges and strategies ................................................4-14

Table 4–4. Summary of Advanced Simulation and Computing challenges and strategies..................................4-18

Table 5–1. Summary of Secure Transportation Asset challenges and strategies..................................................5-5

Table 5–2. Defense Nuclear Security Program elements......................................................................................5-7

Table 5–3. Summary of Defense Nuclear Security Program challenges and strategies........................................5-9

Table 5–4. Elements of the Information Technology and Cybersecurity Program .............................................5-12

Table 5–5. Technologies deployed or to be deployed to address Information Technology and 

Cybersecurity threats.........................................................................................................................5-15

Table 5–6. Summary of Information Technology and Cybersecurity challenges and strategies.........................5-16

Table 7–1. Summary of challenges and strategies for recruiting, developing, retaining, and 

sustaining the workforce ...................................................................................................................7-19

Table 8–1. Overview of Future Years Nuclear Security Program budget request for Weapons Activities 

in fiscal years 2023–2028.....................................................................................................................8-3

Table 8–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant Value of Active 

Facilities.............................................................................................................................................8-20

Table 8–3. Projected FY 2024 DOE/NNSA infrastructure maintenance and recapitalization investments.........8-20

Table 8–4. DOE/NNSA cost estimates for Stockpile Major Modernization Programs ........................................8-27

Table 8–5. Total estimated cost for B61-12 Life Extension Program ..................................................................8-29

Table 8–6. Total estimated cost for W88 Alteration 370 Program (with conventional high explosive 

refresh) ..............................................................................................................................................8-30

Table 8–7. Total estimated cost for W80-4 Life Extension Program...................................................................8-31

Table 8–8. Total estimated cost for W87-1 Modification Program.....................................................................8-32

Table 8–9. Total estimated cost for W93 Program .............................................................................................8-32

Table 8–10. Total estimated cost for Future Strategic Missile – Land-Based Warhead........................................8-33

Table 8–11. Total estimated cost for Future Strategic Missile – Sea-Based Warhead..........................................8-33

Table 8–12. Total estimated cost for Future Air-Delivered Weapon ....................................................................8-33

Table 8–13. Total estimated cost for Future W76-1/2 Replacement....................................................................8-33

Table 8–13. Capital Acquisition Cost Estimate Classification System....................................................................8-36
Department of Energy/National Nuclear Security Administration | November 2023

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Table C–1. NNSA Exascale Computing Initiative funding schedule for FY 2024 ................................................... C-3

Table E–1. The nuclear security industrial base risk factors..................................................................................E-2

Table F–1. Lawrence Livermore National Laboratory capabilities........................................................................F-7

Table F–2. Los Alamos National Laboratory capabilities.....................................................................................F-18

Table F–3. Sandia National Laboratories capabilities..........................................................................................F-28

Table F–4. Kansas City National Security Campus capabilities............................................................................F-39

Table F–5. Pantex Plant capabilities....................................................................................................................F-48

Table F–6. Savannah River Site capabilities ........................................................................................................F-55

Table F–7. Y-12 National Security Complex capabilities .....................................................................................F-63

Table F–8. Nevada National Security Site capabilities ........................................................................................F-70
A Report to Congress

Fiscal Year 2024 Stockpile Stewardship and 

Management Plan

November 2023

U.S. Department of Energy

National Nuclear Security Administration

1000 Independence Avenue, SW

Washington, DC 20585

DOE/NA-0137