Fiscal Year 2023

Stockpile Stewardship and 

Management Plan – Biennial 

Plan Summary

Report to Congress

April 2023

National Nuclear Security Administration

United States Department of Energy

Washington, DC 20585

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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page i

Message from the NNSA Administrator

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

designing, producing, delivering, and certifying the U.S. nuclear stockpile including the advancement of

the underlying science and technology. The Fiscal Year 2023 Stockpile Stewardship and Management 

Plan – Biennial Plan Summary describes our efforts to implement the Administration’s 2022 Nuclear 

Posture Review by maintaining a safe, secure, reliable, and effective nuclear weapons stockpile without 

nuclear explosive testing and revitalizing the nuclear security enterprise. Keeping with DOE/NNSA’s

commitments to Congress and the public, updated versions of the Stockpile Stewardship and 

Management Plan (SSMP) reports are published each year. 

Included in the fiscal year (FY) 2023 SSMP are the details to accomplish the program requirements 

including producing 80 plutonium pits per year; continuing production of the B61-12 Life Extension 

Program (LEP) and the W88 Alteration 370 warheads on schedule; and achieving the first production units

for the W80-4 LEP and W87-1 Modernization Program. The report also discusses other major activities in 

stockpile modernization, infrastructure refurbishment, science, research, technology, and engineering.

Because of the ages of the weapons in the stockpile, new stockpile requirements, and the recapitalization 

needed in the production and science infrastructure, DOE/NNSA has been conducting weapon and 

infrastructure modernization simultaneously. Conducting these programs side-by-side is challenging

because of the intense coordination required across the enterprise and with our partners in the 

Department of Defense. The SSMP describes on-going and planned activities. 

The scientific and technological expertise of the people in the nuclear security enterprise is the backbone 

of the United States’ deterrence. Our nuclear security enterprise workforce comprises experts at 

government-owned, contractor-operated national laboratories, production plants, and sites across the 

country and a smaller Federal workforce for planning, budgeting, management, and oversight. Since the 

days of the Manhattan Project, this model and the specialized talent of nuclear security enterprise 

personnel have delivered the stockpile needed for effective deterrence in the face of changing world 

conditions. The SSMP discusses the recruiting and retention efforts to attract the best talent in the United 

States.

For more than 75 years, the nuclear security enterprise has been at the forefront of cutting edge scientific 

and engineering work that has greatly enhanced national and global security. With continued support 

from Congress, DOE/NNSA will continue to anticipate future security challenges and deliver innovative 

solutions to meet them. Pursuant to statute, this FY 2023 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
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The Honorable Roger Wicker

Ranking Member, Senate Committee on Armed Services

The Honorable Dianne Feinstein

Chairman, Subcommittee on Energy and Water Development

Senate Committee on Appropriations 

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 De Lauro

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 Fleischmann

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
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The Honorable Seth Moulton

Ranking Member, Subcommittee on Strategic Forces

House Committee on Armed Services 

Should you have any questions or need additional information, please contact Dr. Benn Tannenbaum, 

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) works hand in hand 

with the Department of Defense to maintain a safe, secure, and effective nuclear deterrent. The evolving 

global security environment involving two nation state nuclear competitors, coupled with an 

unprecedented range and mix of threats, means the United States must maintain a modern nuclear 

deterrent coupled with flexible and resilient capabilities. This report describes the activities and plans in 

DOE/NNSA to achieve these goals. 

DOE/NNSA’s advancements and innovations in science and engineering has paved the way for 

advancements in national defense and the future of clean power. In December 2022, the DOE/NNSA 

Lawrence Livermore National Laboratory achieved the first controlled fusion experiment in history –

obtaining ignition by producing more energy from fusion than the laser energy used to drive it. This 

landmark achievement provides both unprecedented capability to gain new understanding for stockpile 

stewardship and invaluable insights into the prospects of clean fusion energy. It will undoubtedly spark 

even more discovery and other breakthroughs will be achieved.

This Administration is committed to investing the appropriate resources to support a responsive and 

resilient nuclear security enterprise. With the continued support of Congress, DOE/NNSA will provide a

safe, secure, and effective nuclear stockpile now and into the future. 

Sincerely, 

Jennifer Granholm

Secretary of Energy
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Executive Summary

The Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary (SSMP), 

including its classified annex, describes the Department of Energy’s National Nuclear Security 

Administration (DOE/NNSA) program for implementing the Administration’s Nuclear Posture Review by 

maintaining the nuclear stockpile’s safety, security, and effectiveness over the next 25 years. DOE/NNSA

publishes the SSMP annually, either in full report form or as a summary, in response to statutory 

requirements to support the President’s Budget Request to Congress for Weapons Activities. Consistent 

with the Nuclear Weapons Council Strategic Plan for FY 2019 – 2044, this fiscal year (FY) 2023 summary 

report provides an integrated picture of 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 manage weapons modernization needs 

from concept assessment to full-scale production to retirement. This SSMP reflects rigorous mapping of 

nuclear security enterprise capabilities to address military requirements and the priorities identified in 

the 2022 Nuclear Posture Review.

In 2021, DOE/NNSA executed its largest program in its 21-year history, helping to advance the Nation’s 

nuclear security mission through innovative science and technology solutions. DOE/NNSA worked to 

ensure the existing nuclear weapons stockpile’s safety, security, and reliability; successfully produced the 

first refurbished weapon for two different warheads in the stockpile; continued to modernize 

infrastructure and advance plutonium pit production-related activities; reduced nuclear proliferation risks 

by securing and downblending nuclear materials; helped increase U.S. radiological response capacity; and 

continued to power the nuclear Navy.

DOE/NNSA’s top priority is to deliver on its commitments across the board in a cost-effective manner. 

DOE/NNSA will forge transparent, productive, and enduring relationships with the interagency, its 

stakeholders, and itsinternational allies and partners. By leveraging itsinnovative science and technology 

capabilities, DOE/NNSA will meet stockpile milestones, improve its ability to monitor future arms control 

and nonproliferation agreements, and establish a resilient enterprise to meet the geopolitical needs 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 

Coronavirus Disease 2019 (COVID-19)-related restrictions and supply chain delays, DOE/NNSA has

continued to meet the Nation’s nuclear deterrent requirements.

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 explosive).

◼ Achieve the first production unit of the W80-4 warhead Life Extension Program (LEP) and ensure 

alignment with the DoD Long Range Standoff (LRSO) cruise missile replacement program.

◼ Support fielding Sentinel, formerly known as the Ground Based Strategic Deterrent, and advance 

the W87-1 Modification Program (formerly called the W78 Replacement Warhead).
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◼ Provide the enduring plutonium pit production capability to produce 80 plutonium pits per year 

(ppy).

◼ Assure 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 to support the annual assessment and 

certification of the stockpile.

Key Accomplishments:

Sustain the Stockpile

In 2021, DOE/NNSA:

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

◼ Completed over 1,600 critical equipment calibrations on time in support of production activities. 

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

previous record, and sustained base capabilities for multi-system operations and maintenance 

support to meet all limited life components exchange gas transfer system 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 

generation of laboratory director letters to the President.

◼ Maintained its Office of Secure Transportation’s spotless record by accomplishing 100 percent of 

assigned missions safely and securely, with no mission degradation despite the operational 

challenges inherent during the COVID-19 pandemic. 

Modernize Weapons

◼ Completed the first production unit for the W88 Alt 370 in July 2021 and B61-12 LEP in November 

2021, successfully producing the first refurbished weapons of each type and ready to produce the 

quantities needed by the military. This work helps modernize America’s nuclear weapons 

stockpile, sustain the Nation’s nuclear deterrent capabilities, and improve the safety, security, 

and reliability of the Nation’s weapons. The W88 Alt 370 is carried on the Ohio-class ballistic 

missile submarines and will modernize older W88 warheads. The B61-12 will consolidate, and 

replace, three older B61 warheads variants and will be certified for delivery on strategic and dual 

capable military aircraft. The W88 Alt 370 and B61-12 LEP programs will be completed in FY 2026.

◼ Completed initial joint LRSO/W80-4 testing and component Baseline Design Reviews in 

preparation for transition to Phase 6.4, Production Engineering, in FY 2023.

◼ Completed its W87-1 Modification Program Weapon Design and Cost Report and prepared to 

enter Phase 6.3, Development Engineering, in FY 2022.

Strengthen Key Science, Technology, and Engineering Capabilities

Nuclear weapons stockpile and key nonproliferation activities are supported by the technical expertise 

resident in DOE/NNSA’s Federal and management and operating partner workforces. DOE/NNSA 

cultivates technical expertise at the cutting edge in manufacturing, diagnostics, evaluation, and other 
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areas at the plants and sites. DOE/NNSA maintains unparalleled scientific and engineering capabilities at 

the three national security 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:

– Achieve exascale computing by delivering an exascale-capable machine and modernizing the 

nuclear weapons code base

– Develop an operational enhanced capability (advanced radiography and reactivity 

measurements) for subcritical experiments

– Quantify the plutonium aging effects on weapon performance over time

– Assure an enduring, trusted strategic radiation-hardened microsystems supply

◼ Maintain 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.

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

national security laboratories’, production plants’, and sites’ long-term workforces and 

capabilities.

Key Accomplishments:

In 2021, DOE/NNSA:

◼ Delivered two next-generation computational simulation capabilities to support environmental 

specification, design, and qualification for future weapon systems. These code suites have been 

designed to effectively use the full power of DOE/NNSA’s current and next-generation 

supercomputers including the DOE/NNSA exascale system, El Capitan.

◼ Made important contributions to the fight against COVID-19. Los Alamos National Laboratory 

(LANL) led the COVID-19 Testing Team for the DOE’s National Virtual Biotechnology Lab and 

continues to work with Sandia National Laboratories (SNL), and other DOE sites, to help the Nation 

address COVID-19. Lawrence Livermore National Laboratory (LLNL) joined the international 

Human Vaccines Project to aid in developing a universal coronavirus vaccine and improve 

understanding on immune response where LLNL will leverage its knowledge in vaccine research 

response, most recently from designing new antibodies and antiviral drugs for COVID-19. SNL 

contributed by standing up a COVID-19 diagnostic lab for their workforce and NNSA, development 

of reagents for vaccines, and integrated virus monitoring, modeling, and analyst capability to track 

pandemic propagation to inform decisions associated with detection and diagnostics.

◼ Surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to a target, resulting 

in 3.15 MJ of energy output, during a December 5 Inertial Confinement Fusion experiment at 

LLNL’s National Ignition Facility. This wasthe 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 historic, first-of-its kind achievement will provide 

unprecedented capability to support DOE/NNSA’s Stockpile Stewardship Program and invaluable 

insights into the prospects of clean fusion energy.
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◼ Performed two consecutive experiments using the Z pulsed power facility to measure the dynamic 

response of aged plutonium. These 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.

◼ Supported the National Aeronautics and Space Administration’s Perseverance rover landing on 

Mars. Perseverance carried the SuperCam, an instrument designed and built by a LANL-led

international team comprising more than 300 people. SuperCam’s capabilities include breaking 

up far-away rocks to study their composition and features the first scientific microphone to ever 

operate on Mars.

◼ Executed a record three subcritical experiments in a single year while planning and preparing for 

three additional subcritical experiment series to be executed in support of stockpile certification 

needs.

Modernize the Nuclear Security Infrastructure

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:

◼ Recapitalize existing infrastructure to implement a plan to produce 80 ppy. The recommended 

strategy is a two-site solution: 

– Establish a reliable capability at the Plutonium Facility at LANL to deliver 30 WR ppy

– Repurpose the Mixed Oxide Fuel Fabrication Facility at SRS as part of the Savannah River 

Plutonium Processing Facility (SRPPF) to produce 50 ppy as close to 2030 as possible

◼ Enable phasing out mission dependency on Building 9212 at the Y-12 National Security Complex 

in Oak Ridge, Tennessee, 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.

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

Metallurgy Research Replacement Project.

◼ Modernize lithium and tritium facilities.

◼ Increase tritium production using 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 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.
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Key Accomplishments:

In 2021, DOE/NNSA:

◼ Announced the approval of a key design milestone for the Los Alamos Plutonium Pit Production 

Project at LANL and the SRPPF project at SRS. These projects will reestablish, for the first time 

since the early 1990s, the capability to produce War Reserve plutonium pits to ensure the U.S.

nuclear deterrent remains safe, secure, reliable, and effective now and in the future.

◼ Completed the Radiological Utility Office Building Equipment Installation Phase 2 project, 

enhancing the analytical chemistry and material characterization capabilities that support 

plutonium missions at LANL and the DOE/NNSA complex. This project moves programmatic 

operations to a modern facility and was completed two months ahead of schedule and $120 

million under budget.

◼ Hardened its cyber infrastructure this past year, including replacing the Information Assurance 

Response Center’s Enterprise Security Incident and Event Management tool to enhance 

continuous monitoring,

1

threat detection, and rapid investigation and response.

◼ Began to make parts to speed up design development and transition to production efforts in

support of the W80-4 LEP and W87-1 Modification Program at the now-operational LLNL-Kansas 

City National Security Campus Polymer Enclave.

2022 Priorities

Modernize and Maintain America’s Nuclear Weapons Stockpile

In 2022, DOE/NNSA:

◼ Continued to advance its nuclear weapons stockpile modernization, as two key milestones

approach: the W80-4 LEP, where DOE/NNSA will achieve a producible design and prepare for 

production, and the W87-1 Modification Program where NNSA will, in coordination with DoD, 

validate the selected design option and initiate process development activities. The W80-4 LEP 

will ensure the effectiveness of the nuclear triad’s bomber leg when coupled with the Air Force’s 

LRSO cruise missile. The W87-1 will replace the aging W78 warhead to maintain the nuclear 

triad’s intercontinental ballistic missile leg’s safety, security, and effectiveness.

◼ Began implementing the recommendations of an enterprise-wide cybersecurity assessment that 

evaluated DOE/NNSA’s overall cybersecurity posture. A final report was issued in May 2022. The 

assessment team interviewed staff at sites and across the complex on cybersecurity program 

implementation, workforce, supply chain risk management, enterprise architecture and 

technology roadmaps, and budget sufficiency. In addition, DOE/NNSA is committed to implement 

the President’s Executive Order on Zero Trust Architecture (Executive Order 14028) to improve 

the security of information technology systems from cyber attacks.

◼ Advanced its production and infrastructure modernization goals. Revitalizing DOE/NNSA 

infrastructure requires managing a $120 billion enterprise where more than half the facilities are 

in insufficient condition and nearly as many are beyond their life expectancy. In 2022, DOE/NNSA 

continued to improve its new data-driven and risk-informed infrastructure stewardship tools to 

prioritize risks and optimize investment impacts. DOE/NNSA also continued advancing a novel 

1 Continuous monitoring—A strategy that enables information security professionals and others to see a continuous stream of 

near real-time snapshots of the state of risk to their security, data, network, end points, and even cloud devices and applications.
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pilot program that is challenging norms to create a streamlined process for acquiring noncomplex, 

nonnuclear capital construction facilities. Finally, DOE/NNSA and DOE Federal staff moved into 

the newly constructed John A. Gordon Albuquerque Complex.

◼ Continued its efforts to design facilities to produce plutonium pits, including working toward 

reaching a 90 percent design completion and establishing a definitive scope, schedule, and cost 

baseline for the pit production projects at LANL and SRS.
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Fiscal Year 2023 Stockpile Stewardship 

and Management Plan – Biennial Plan Summary

Table of Contents

Legislative Language...........................................................................................................xvii

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

1.1 Overview ..................................................................................................................................1-2

1.2 Policy Framework Summary ....................................................................................................1-3

1.3 Nuclear Weapons Stockpile Summary.....................................................................................1-3

1.4 Overall Strategy, Objectives, and Prioritization of Weapons Activities...................................1-5

1.5 Summary of Key Challenges in Executing the Stockpile Stewardship and 

Management Plan....................................................................................................................1-8

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

2.1 Sustaining the Stockpile...........................................................................................................2-2

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

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 W80-4 Alteration (Sea-Launched Cruise Missile)....................................................2-11

2.2.6 W87-1 Modification Program..................................................................................2-11

2.2.7 W93 Program...........................................................................................................2-11

2.2.8 Future Warheads.....................................................................................................2-12

2.3 Weapon Dismantlement and Disposition..............................................................................2-12

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

2.4 Production Operations...........................................................................................................2-13

2.4.1 Status.......................................................................................................................2-13

Chapter 3 Weapons Activities Capabilities that Support the Nuclear Security Enterprise .... 3-1

3.1 Weapon Science and Engineering Area ...................................................................................3-3

3.1.1 Atomic Physics, Nuclear Physics, Nuclear Engineering, and Radiochemistry ...........3-3

3.1.2 Materials Science, Chemistry, High Explosives and Energetics Science and 

Engineering, and Actinide Science.............................................................................3-5

3.1.3 High Energy Density Science and Plasma Physics......................................................3-6

3.1.4 Technologies to Study Extreme Conditions (Lasers, Accelerators, 

and Pulsed Power).....................................................................................................3-8
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3.1.5 Advanced Experimental Diagnostics and Sensors.....................................................3-9

3.1.6 Hydrodynamic and Subcritical Experiments............................................................3-10

3.1.7 Challenges and Strategies........................................................................................3-11

3.2 Weapon Simulation and Computing Area .............................................................................3-16

3.2.1 High Performance Computing .................................................................................3-16

3.2.2 Simulation Capabilities for Weapon Science, Engineering, and Physics.................3-17

3.2.3 Challenges and Strategies........................................................................................3-18

3.3 Weapon Design and Integration Area....................................................................................3-20

3.3.1 Weapon Physics Design and Analysis......................................................................3-20

3.3.2 Weapon Engineering Design, Analysis, and Integration..........................................3-20

3.3.3 Environmental Effects Analysis, Testing, and Engineering Sciences.......................3-21

3.3.4 Weapons Surety Design, Testing, Analysis, and Manufacturing .............................3-22

3.3.5 Radiation-Hardened Microelectronics Design and Manufacturing.........................3-22

3.3.6 Challenges and Strategies........................................................................................3-23

3.4 Weapon Material Processing and Manufacturing Area.........................................................3-24

3.4.1 Plutonium Management..........................................................................................3-24

3.4.2 Uranium Management ............................................................................................3-28

3.4.3 Lithium Management ..............................................................................................3-35

3.4.4 Tritium Management...............................................................................................3-37

3.4.5 High Explosives and Energetics Management.........................................................3-38

3.4.6 Additional Material Needs.......................................................................................3-42

3.5 Weapon Component Production Area ..................................................................................3-42

3.5.1 Non-Nuclear Component Modernization and Production......................................3-42

3.5.2 Weapon Component and Material Process Development......................................3-45

3.5.3 Weapon Component and System Prototyping........................................................3-46

3.5.4 Advanced Manufacturing ........................................................................................3-47

3.5.5 Challenges and Strategies........................................................................................3-48

3.6 Weapon Assembly, Storage, Testing, and Disposition Area ..................................................3-49

3.6.1 Weapon Assembly, Storage, and Disposition..........................................................3-49

3.6.2 Weapon Component and System Surveillance and Assessment ............................3-49

3.6.3 Testing Equipment Design and Fabrication.............................................................3-50

3.6.4 Challenges and Strategies........................................................................................3-50

3.7 Transportation and Security Area..........................................................................................3-51

3.7.1 Secure Transportation.............................................................................................3-51

3.7.2 Safeguards and Security ..........................................................................................3-52

3.7.3 Information Technology and Cybersecurity ............................................................3-54

Chapter 4 Infrastructure and Operations............................................................................ 4-1

4.1 Infrastructure Planning and Asset Management.....................................................................4-3

4.1.1 Area Planning.............................................................................................................4-4

4.1.2 Weapons Activities Line-Item Planning Integration ..................................................4-4

4.1.3 Critical Decision Acquisition Milestone Process........................................................4-5

4.2 Acquisition ...............................................................................................................................4-6

4.2.1 Programmatic Construction ......................................................................................4-7

4.2.2 Mission Enabling Construction................................................................................4-18

4.3 Modernization and Sustainment ...........................................................................................4-22

4.4 Disposition .............................................................................................................................4-24
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Chapter 5 Budget and Fiscal Estimates............................................................................... 5-1

5.1 Planning, Programming, Budgeting, and Evaluation ...............................................................5-1

5.2 Portfolio Management.............................................................................................................5-2

5.3 FY 2023 Future Years Nuclear Security Program .....................................................................5-2

5.4 Stockpile Management............................................................................................................5-3

5.4.1 Budget........................................................................................................................5-4

5.4.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget..............................5-4

5.4.3 Key Milestones ..........................................................................................................5-6

5.5 Production Modernization.......................................................................................................5-6

5.5.1 Budget........................................................................................................................5-7

5.5.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget..............................5-7

5.5.3 Key Milestones ..........................................................................................................5-9

5.6 Stockpile Research, Technology, and Engineering.................................................................5-13

5.6.1 Budget......................................................................................................................5-13

5.6.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget............................5-14

5.6.3 Key Milestones ........................................................................................................5-16

5.7 Infrastructure and Operations...............................................................................................5-17

5.7.1 Budget......................................................................................................................5-17

5.7.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget............................5-18

5.7.3 Key Milestones ........................................................................................................5-20

5.7.4 Infrastructure Maintenance and Recapitalization Investments..............................5-20

5.8 Other Weapons Activities......................................................................................................5-21

5.8.1 Budget......................................................................................................................5-21

5.8.2 Secure Transportation Asset ...................................................................................5-22

5.8.3 Defense Nuclear Security ........................................................................................5-23

5.8.4 Information Technology and Cybersecurity ............................................................5-24

5.8.5 Legacy Contractor Pensions and Settlement Payments..........................................5-26

5.9 Budget Projections Beyond FY 2027 ......................................................................................5-26

5.9.1 Basis for Budget Projections....................................................................................5-26

5.9.2 Stockpile Major Modernization...............................................................................5-26

5.9.3 Construction ............................................................................................................5-36

5.10 Affordability ...........................................................................................................................5-38

Chapter 6 Conclusion......................................................................................................... 6-1

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-8

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-10

A.8 Related Legislation: 50 U.S. Code § 2524............................................................................. A-10

A.9 Related Legislation: 50 U.S. Code § 2538b........................................................................... A-11

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

A.11 Related Legislation: S. 1605A NDAA for FY 2022 ................................................................. A-12
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page xvi

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

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

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

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 Workforce Retention....................................................................................... C-1

C.1 Challenges and Approaches.....................................................................................................C-1

C.2 Demographics (Snapshot as of September 30, 2021)..............................................................C-3

Appendix D Exascale..........................................................................................................D-1

D.1 Challenges............................................................................................................................... D-2

D.2 Approaches and Strategies..................................................................................................... D-2

D.3 Collaborative Management .................................................................................................... D-4

D.4 Milestones............................................................................................................................... D-4

D.5 Conclusion............................................................................................................................... D-5

Appendix E Stockpile Responsiveness Program .................................................................. E-1

Appendix F Industrial Base................................................................................................. F-1

F.1 Framework ...............................................................................................................................F-1

F.2 Risk Management ....................................................................................................................F-1

F.2.1 Monitoring.................................................................................................................F-2

F.2.2 Mitigation ..................................................................................................................F-2

F.3 Interagency Coordination ........................................................................................................F-2

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

Appendix H Acronyms .......................................................................................................H-1

Appendix I Figures and Tables............................................................................................. I-1
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page xvii

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 2023 Stockpile Stewardship and Management Plan (SSMP) is a biennial plan summary 

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 DoD 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

Strategic Context for Managing the 

Nuclear Weapons Stockpile

The U.S. nuclear deterrent is the foundation of the national defense, which backstops U.S. integrated 

efforts across warfighting domains, other instruments of national power, and the United States’ network 

of alliances and partnerships. While eliminating nuclear weapons has been a goal for generations, current 

activities by several nuclear powers appear to be at odds with this goal. Russia is relying on nuclear 

weapons as a means to counter U.S. conventional superiority, replacing Soviet-era systems with new 

missiles, submarines, and aircraft while developing new types of tactical nuclear weapons. China is trying 

to broaden its political and economic influence, and in the nuclear arena, is increasing the number and 

types of nuclear weapons in its arsenal. Further, North Korea has expanded its number of nuclear 

weapons and range of delivery capabilities, and Iran continues to develop its nuclear program. For the 

foreseeable future, nuclear weapons will continue to provide unique deterrence effects that no other 

element of U.S. power can replace given the reality of today’s evolving and uncertain international 

security environment. 

Ensuring the U.S. strategic deterrent remains safe, secure, and effective, 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. 

To execute the Nation’s nuclear weapons programs, DOE/NNSA partners with DoD through the Nuclear 

Weapons Council on the joint nuclear weapons life cycle process. 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 continues to perform an unprecedented 

variety of component development, qualification, system integration, and production activities.

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

and DOE/NNSA’s infrastructure is currently adequate to support stockpile actions. However, continued 

science and infrastructure investments are needed to ensure the stockpile continues to meet these 

requirements. For most of the post-Cold War period, the focus of the 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. Additionally, elements 

of the production infrastructure were dismantled, and other elements were not sustained due to limited 

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

risks, a partial refurbishment strategy no longer meets the needs of the nuclear deterrent. To respond to 

the current environment with a balanced, flexible stockpile, it is important that the nuclear security 

enterprise’s production infrastructure is re-established, repaired as appropriate, and modernized. 

Recapitalizing the nuclear security enterprise, including the workforce, infrastructure, production capacity 

and capabilities, and scientific base that support it, is key to ensuring a safe, secure, and effective 

stockpile. A resilient and responsive production capability is necessary for DOE/NNSA to continue to 

support the nuclear deterrent and afford the United States the ability to adapt to changes in the strategic 

environment. Therefore, DOE/NNSA is currently undertaking a risk-informed, complex, and 

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

conjunction with the priorities identified in the 2022 Nuclear Posture Review. 

1.1 Overview

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.). 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 enables DOE/NNSA to manage the U.S. nuclear weapons stockpile 

while employing science-based stockpile stewardship to enhance the potential performance 

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

– Maintain and modernize the supporting infrastructure

– Sustain DOE/NNSA’s highly skilled workforce necessary for this work

◼ Provide DOE/NNSA’s formal response to multiple statutory 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) 
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This fiscal year (FY) 2023 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).

1.2 Policy Framework Summary

The National Nuclear Security Administration Act (50 U.S.C § 2401, et seq.) 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 reinforced 

that the United States will maintain nuclear forces that are responsive to the threats we face, and affirmed 

the following roles for nuclear weapons:

◼ Deter strategic attacks

◼ Assure Allies and partners

◼ Achieve U.S. objectives if deterrence fails

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 remain a top priority for 

DoD, DOE/NNSA, and the Nation. 

1.3 Nuclear Weapons Stockpile Summary

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

needs, though the average warhead age in the stockpile remains high. Many weapons are considerably

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

condition and perform additional maintenance and enhanced surveillance to ensure operability and 

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

making significant progress toward reducing the average warhead age, while concurrently looking to meet 

emerging challenges on a time scale that does not put the U.S. nuclear deterrent at risk. DOE/NNSA is 

also enhancing its science, technology, and engineering capabilities to improve the production processes’

efficiency and effectiveness. The change in the nuclear weapons stockpile’s size and age over time is 

illustrated in Figure 1–1.

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.
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Figure 1–1. Size and age of the U.S. nuclear weapons stockpile, 1945–2020

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 Non-strategic 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

B83‐1 Strategic bomb B‐2 bomber LLNL/SNL Air to surface Air Force

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.
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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, the nuclear weapons required for those platforms, and 

the DOE/NNSA infrastructure needed to produce and maintain those weapons. This approach will ensure 

the necessary flexibility needed for future policy decisions related to nuclear modernization as the United 

States adjusts to the changing international threats facing the United States 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 weapons and infrastructure modernization programs to provide 

the capabilities needed to ensure the deterrent’s viability into the future. For these reasons, DOE/NNSA 

continues to look for innovative ways to meet emerging challenges on a timescale that does not put the 

U.S. nuclear deterrent at risk and to enhance science, technology, and engineering capabilities to improve 

production processes efficiency and effectiveness. 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 2023 budget for Weapons Activities includes funding for major 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.

◼ Develop the W93. The W93 Modernization Program is a new program of record established to 

support the Navy’s identified need for a new reentry body. Anchored on previously tested nuclear 

components, the 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 

ensure 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.

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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Carrying out the W93 program is vital for continuing 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

◼ Synchronizing DOE/NNSA’s W80-4 warhead with DoD’s Long Range Standoff (LRSO) cruise missile 

program and supporting the Air Force’s scheduled LRSO initial and final operational capability 

dates

◼ Exploring future ballistic missile warhead options to meet the required military characteristics 

based on the threats and vulnerabilities of potential adversaries, including possible common 

reentry systems for Air Force and Navysystems

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

mission priorities to maintain the safety, security, and effectiveness of the Nation’s nuclear deterrent; 

strengthen key science, technology, and engineering capabilities; and modernize the nuclear security 

infrastructure 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

– Developing modern materials and design and manufacturing options to enable a more modern 

and efficient production complex

– Maintaining a nuclear explosive test capability as a safeguard

◼ 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-term and long-term (Note: 

These capabilities are discussed in Chapter 3, “Weapons Activities Capabilities that Support the 

Nuclear Security Enterprise”):

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

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

and subsystems
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◼ 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

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 Summary of Key Challenges in Executing the Stockpile 

Stewardship and Management Plan

DoD continues to make progress on the first recapitalization of the triad1since 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 the delivery of 

timely and cost-effective capabilities that meet the defense needs of the Nation. The partnership 

between DoD and DOE/NNSA continues to thrive through the interagency Nuclear Weapons Council, 

which has made tremendous progress to align priorities, schedules, and investments between the 

Departments to ensure the Nation’s nuclear deterrent’s future viability.

Nearly all the systems that comprise the current U.S. nuclear deterrent are well beyond their original 

service lives and further life extensions to meet future requirements are no longer cost-effective. DoD is 

addressing challenges within its aging nuclear command, control, and communications system; delivery 

systems; and platforms, and DOE/NNSA is addressing similar challenges as the nuclear warheads in the 

stockpile continue to age. Additionally, much of the DOE/NNSA nuclear weapons infrastructure continues 

to require near-term and longer-term investments to provide a safe, and secure working environment 

with the capabilities and capacities necessary to meet military requirements. As a result, the nuclear 

security enterprise faces a challenge acquiring and fielding modern replacement systems concurrently in 

each leg of the triad while also investing in an updated nuclear weapons stockpile and supporting 

infrastructure. 

One of the most critical challenges that DOE/NNSA must address is the modernization and recapitalization 

of existing infrastructure in parallel with increasing mission requirements. Components, subsystems, 

buildings, and equipment need to be replaced, not just life extended. This necessity is particularly critical 

for the production facilities and strategic material production capabilities and capacities within the 

nuclear security enterprise. 

DOE/NNSA has resourced plans to renew the essential time-critical 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 an 80 pits per year production capability

◼ Reestablishing high explosives synthesis, formulation, and production capabilities

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

1 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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Figure 1–3. Timeline for key infrastructure and capability investments for future warheads

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

processes, technologies, and tools to design, qualify, certify, and produce warheads 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

◼ Pursuit of only the priority activities described above does not exercise all phases and aspects of 

the joint nuclear weapons life cycle. 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 life cycle, and strengthen integration between 

DoD and DOE/NNSA to ensure sustainment of all required capabilities. This continued focus is 

reflected in the inclusion of Appendix E, which resubmits information on the programs, projects, 

and activities of the Stockpile Responsiveness Program. 

◼ The nuclear weapons supply chain availability and trustworthiness must be sustained 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 assure 

supply chain protection. 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 ensure continued capability. DOE/NNSA is also interacting and collaborating with
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partners to establish research and development efforts that could serve as a future production 

capability. 

◼ In FY 2021 DOE/NNSA developed the nuclear security enterprise industrial base (NIB) monitoring 

framework to provide for the continued viability of the nuclear weapons stockpile. This 

framework takes a holistic approach to monitoring the industrial base that supports nuclear 

weapons components, subsystems, and materials through the establishment of four pillars. 

These four interdependent pillars of activities (supply chain, operations, logistics, and workforce) 

function in concert to ensure that challenges to maintaining the stockpile are viewed with a broad 

lens and that gaps or risk in specific areas relating to the NIB are proactively identified. Many of 

these challenges within specific areas of the NIB are presented throughout the SSMP, along with 

ongoing and future mitigation strategies. The monitoring framework leverages the management 

processes of numerous programs, working groups, and teams across the nuclear security 

enterprise and continues to evolve to properly account for a continuously changing national 

security environment. A new addition to the FY 2023 SSMP, Appendix F, provides further details 

on the framework and DOE/NNSA’s approach to monitoring the NIB.
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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 tools that underpin these efforts. 

DOE/NNSA coordinates and plans with the Department of Defense 

(DoD) through the Nuclear Weapons Council to manage the current 

and future stockpile through four major program areas:

◼ Stockpile Sustainment performs single-system and multisystem sustainment activities (i.e., assessment, surveillance, maintenance, and response to 

emerging issues) for all weapons systems in the stockpile. Stockpile Sustainment includes limited 

life component (LLC) exchanges, surveillance activities, significant finding investigations (SFI), 

weapons reliability reporting, and annual assessments that provide a comprehensive 

understanding of the health of the stockpile.

◼ Stockpile Major Modernization includes life extension programs (LEPs), modification programs

(Mod), and major Alts that extend the life of weapons in the stockpile, enhance system security 

and safety features, and address issues related to aging or component obsolescence. It also 

includes modernization programs that do not constitute an LEP, Mod, or Alt, but provide a 

modernized warhead capability (e.g., the W93).

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

disposition of weapon components, which can generate components and materials for Weapons 

Activities and other DOE/NNSA mission areas.

◼ Production Operations provides DOE/NNSA with a multi-system manufacturing-based program 

that drives site production base capabilities for warhead modernization activities, weapon 

maintenance, surveillance, weapon assembly and disassembly, and weapon reliability and safety 

testing. Production Operations encompasses sustaining all weapon systems capabilities that 

enable weapon production and are not specific to one material stream. It coordinates closely 

with Production Modernization, which focuses on the special nuclear materials and components 

(such as plutonium and uranium), as well as non-nuclear component modernization. These 

capabilities are discussed in Chapter 3. 

The remainder of Chapter 2 is organized around these four major areas as depicted in Figure 2–1. 

Stockpile Management 

Accomplishments

• Completed Annual Assessment 

Cycle 26

• Achieved B61-12, W88 Alt 370,

and W87-1 deliverables

• Achieved goals for Stockpile 

Sustainment activities
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Figure 2–1. Major Stockpile Management Programs

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 tasks. These individual capabilities and the linkages 

to stockpile management are described in Chapter 3. Chapter 4 and Appendix C 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 used to support the 

enduring stockpile mission. To achieve success in these areas, it is crucial that every capability listed in 

Chapter 3 of this Stockpile Stewardship and Management Plan – Biennial Plan Summary (SSMP) is healthy

and fully and efficiently executed.

2.1 Sustaining the Stockpile

Stockpile sustainment activities are prioritized and performed to ensure the daily health of the stockpile. 

These activities include surveillance, annual assessments, and routine maintenance to ensure weapons 

remain safe, secure, and effective over the projected life cycle. Weapons that remain in the stockpile are 

eventually updated through modernization programs to address modified military requirements, resolve

any anomalies, and meet updated safety and security standards. These modernization activities (LEPs, 

Mods, and Alts) are addressed through the Stockpile Major Modernization activities discussed in 

Section 2.2.

2.1.1 Assessing the Stockpile

The status of the stockpile is evaluated through continuous, multi-layered assessments of the safety, 

security, and military effectiveness of each U.S. nuclear weapon system. The annual stockpile assessment 
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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 

may also evaluate the effects of aging on performance and quantify performance thresholds, 

uncertainties, and margins. They assemble a body of evidence to measure performance at the part, 

component, subsystem, and system levels to determine whether required performance characteristics 

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 directors of the three national security laboratories conduct independent annual assessment reviews

on the state of all stockpile systems for which they are responsible. The Commander of the U.S. Strategic 

Command (USSTRATCOM) is also required by statute (50 U.S. Code 2525) 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, considering 

information generated by the SSMP in the past year. 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 Red Teams and 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, which 

are included as unabridged attachments to the statutorily required Report on Stockpile Assessments, 

prepared annually by the Nuclear Weapons Council for formal endorsement by the Secretaries of Energy 

and Defense, and submitted to the President. 

2.1.1.2 Weapon Reliability

Each September, DOE/NNSA publishes the 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 the effects of test limitations. 

The 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 methodologies, diagnostic and experimental 

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 and possible failure modes, improve the quantification of margins and uncertainties, and 

improve the fidelity and agility of certification methodologies. 

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

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

abnormal, and hostile environments. Qualification plans for each stockpile system lay out the 
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experimental data, modeling, simulation capabilities, and production data required to ensure system 

functionality. 

While qualification is carried out by each warhead program, Advanced Qualification activities seek to 

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, often with 

increased responsiveness or enhanced properties. These activities are key to address the qualification 

challenges for advanced manufacturing methods, for replacement materials, and for 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 

development of design for manufacturability. Close coordination between materials and components

development and between design and production agencies enables design for manufacture. 

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 of 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 functioning is performing properly. Uncertainty is the 

degree to which these values are known. 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 and experimental platforms used to 

simulate warhead operation. In summary, quantification of M/U provides an increased understanding of 

the basis for the assessed confidence in the weapons system performance.

2.1.2 Stockpile Surveillance

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

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

future stockpile decisions regarding weapon LEPs, Alts, Mods, or other weapon systems not in those 

categories based on the assessment activities described above. The surveillance program has six goals: 

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

performance

◼ Assess risks to the safety, security, and performance of the stockpile

◼ Determine the margins between design requirements and performance at the system, 

component, and material levels

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

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

components and materials

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

Assessments
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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 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 give important clues to the health of the weapons while also advancing inspection 

technologies and techniques that enhance 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 Testing Equipment

Testers can be applied to systems, subsystems, major components, and processes. Testers perform two 

key functions. First, they provide the mechanical, electrical, and radiofrequency stimuli to the system in 

a specified sequence to evaluate component functionality relative to requirements. Second, the testers 

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, and effective.

2.1.2.4 Anomaly Investigative Process

When anomalies that could significantly affect weapon safety, security, reliability, or effectiveness arise 

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

to determine whether observations warrant an SFI. SFIs are also opened for anomalies discovered 

anywhere in the stockpile when unexpected phenomena are observed. Such occurrences are investigated 
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by the design agency responsible for the anomalous component. Investigations can include modeling of 

historical data, 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 progress from initial discovery through closure, and the status of any corrective actions taken.

2.1.3 Maintaining the Stockpile

Maintaining the current stockpile comprises many ongoing activities:

◼ Completing LLC exchanges of gas transfer systems (GTS), 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 the 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. Modern GTS 

designs extend LLC intervals and 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. 

Power Sources

Current and future planned nuclear weapons require compact, highly 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 not readily available from 

commercial suppliers. This capability supports nuclear weapons and other national security missions, 

including prototyping and parts development, through the full life cycle requirements of power source 

components through early-stage R&D and modeling, technology maturation, design and development, 

production, surveillance, and disassembly. 
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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 life cycle to meet DOE/NNSA’s commitments, 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 across 

the stockpile 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 

2.2 Stockpile Major Modernization

Stockpile major modernization activities are performed through a series of planned LEPs, Mods, and Alts 

enabled by a strong set of science, technology, and engineering 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.

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 an advanced digital enterprise that promotes system 

1 Stated in 50 U.S.C. 2538 (d).

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

B61-12 LEP

Tactical/Strategic Bomb

W87-1 Modification Program

(formerly W78 Replacement Warhead)

Phase X/6.X Process and the

Stockpile Modernization Program

22 23

W88 Alt 370 / CHE Refresh

Submarine-Launched Ballistic Missile Warhead

W80-4 LEP

Cruise Missile Warhead

24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 45

Submarine Launched Warhead

(Enables replacement of the W76-1/2)

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)

(Activities at Pantex and Y-12) 41 42 43 44 46 47

6.3-6.5 

6.3-6.5

FPU

FY 2022

Notional FPU

Early 2030s

Notional FPU

Mid 2030s

FPU

FY 2027

6.5-6.6

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)
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modernization activities, and exercise capabilities through the Stockpile Responsiveness Program. These 

improvements will enhance the Nation’s ability to counter adversaries’ capabilities, stockpile aging, and 

variables associated with supporting U.S. hedge capabilities.

Qualification-ready and certification-ready 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 Nuclear Weapons Council 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 3.

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 then Atomic 

Energy Commission and DoD, which introduced the concept of weapon acquisition phases. The original 

agreement was supplemented over the years to clarify various areas of joint departmental cooperation. 

However, the United States’ decision to halt underground nuclear explosive testing in 1992 affected the 

joint agreement as it was no longer updated regularly. Emerging DoD requirements for future systems 

necessitated updated procedural guidelines defining the full seven phase nuclear weapons life cycle. This 

necessity was accomplished through the recently implemented Phase X Process, which updates the 

original agreement and the joint DoD and DOE/NNSA procedures governing the full life cycle for nuclear 

weapons.

The updated guidelines also supplement the existing Nuclear Weapons Council-approved Procedural 

Guidelines for the Phase 6.X Process, which define the framework for existing nuclear weapon 

refurbishment activities. The Phase X Process includes procedures for program study, development, 

production, sustainment, and nuclear weapons systems dismantlement. 

Joint DoD-DOE/NNSA nuclear weapons life cycle guidelines, including those under the Phase X and the 

Phase 6.X Processes, support increasing emphasis on modernization activities to sustain U.S. nuclear 

deterrence priorities and capture DoD-DOE/NNSA best practices for nuclear weapons acquisition and 

sustainment. The Nuclear Weapons Council’s Procedural Guidelines for the Phase 6.X Process provide the 

framework for nuclear weapon refurbishment activities and will continue to be used, even with the 

updated Phase X Procedural Guidelines for Phase 1-7 nuclear weapon design, development, production, 

sustainment, and dismantlement activities. 

2.2.1.1 Phase 6.X Process

Nuclear weapons have been historically developed, produced, maintained, retired, and dismantled in a 

process known as the Nuclear Weapons Life Cycle (now Phase X). This process 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. DOE/NNSA’s Major Stockpile Modernization activities have been guided by the Phase 6.X 

Process instead, which was developed for non-routine Alts, Mods, and LEPs and starts from an existing 

warhead design, rather than being used to develop and field a complete warhead. The phases of this 

process are very similar to stages 1–6 of the life cycle. These phases, and the relation of the Phase 6.X 

Process to the Nuclear Weapons life cycle, are shown in Figure 2–3.
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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

The B61-12 received authorization to enter Phase 6.5, First 

Production, in fiscal year (FY) 2021, and completed its 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 

B61-12 LEP required re-planning to allow re-qualification of 

base metal electrode affected components,2similar to the 

W88 Alt 370. The requalification efforts are on or ahead of the 

re-baselined plan. 

2

In FY 2019 – FY 2020, DOE/NNSA experienced technical issues associated with a limited number of electrical components that 

affected some production component schedules. This base metal electrode issue led to re-planning of the schedules for both the 

B61-12 LEP and the W88 Alt 370 programs.

DOE/NNSA achieved the first production unit for 

the B61-12 LEP on November 23, 2021
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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 received authorization to enter Phase 6.5 in FY 2021 and completed the system-level 

first production unit in July 2021. The Nuclear Weapons Council formally accepted the W88 Alt 370 into 

the stockpile in December 2021 and authorized Phase 6.6, Full-Scale Production, entry in 2022. The W88 

Alt 370 required replanning to allow re-qualification of base metal electrode-affected components, like

the B61-12. Requalification efforts were completed in the third quarter of FY 2021, in accordance with 

the re-baselined plan. 

2.2.4 W80-4 Life Extension Program

The W80-4 LEP will deploy with the Air Force’s 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 will improve the Air Force’s 

capability to defeat adversary Integrated Air Defense Systems 

by enhancing the bomber force’s delivery and survivability 

capabilities. The W80-4 LEP is on track to support fielding the 

Air Force’s scheduled LRSO cruise missile initial and final 

operational capability dates.

2.2.4.1 Status

In FY 2019, the Nuclear Weapons Council directed entry of the

W80-4 LEP into Phase 6.3, Development Engineering. During 

this phase, weapon system design will continue to be refined. 

There are four primary deliverables:

◼ Baseline design, which will advance production 

engineering processes 

◼ Preliminary Design Review and Acceptance Group 

Review, which will indicate DoD acceptance of the 

baseline design and its associated plan for certification

◼ Baseline Cost Report

◼ Nuclear Weapons Council approval of the military characteristics and STS

The W80-4 program office anticipates entering Phase 6.4, Production Engineering, in the second quarter 

of FY 2023.

The LRSO and W80-4 Life Extension 

Program joint test teams completed the first 

powered flight test of a LRSO Cruise Missile 

with W80-4 Warhead released from a B-52 

aircraft. The missile successfully released 

from the aircraft, powered its engine, and 

executed all in-flight maneuvers. A Lawrence 

Livermore National Laboratory (LLNL) and 

Sandia National Laboratories (SNL) team 

developed the warhead test asset, an 

Environmental Test Unit. The Environmental 

Test Unit successfully executed all prearm/pre-release criteria and collected 

environmental data for the duration of the 

flight. This is a significant milestone for the 

joint program and first collection of 

representative LRSO free flight data, used to 

populate the W80-4 STS, define 

environmental specifications, inform design 

decisions, and validate computational models.
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2.2.5 W80-4 Alteration (Sea-Launched Cruise Missile)

After extensive interagency deliberation and approval of the 2022 Nuclear Posture Review, it was

determined that the Sea-Launched Cruise Missile-Nuclear (SLCM-N) program was no longer needed. The 

2022 Nuclear Posture Review made this determination in light of the deterrence contributions of the 

W76-2 and other capabilities, as well as the program’s estimated cost relative to other ongoing nuclear 

modernization efforts. Therefore, consistent with the Administration’s 2022 Nuclear Posture Review, 

DOE/NNSA did not request funding for this program. 

2.2.6 W87-1 Modification Program

The W87-1 will be deployed alongside the W87-0 on the Sentinel, formerly known as the Ground Based 

Strategic Deterrent. It 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 the only system not to have received a major refurbishment or upgrade. 

Critical W78 components continue to age, while the military requirements for the safety and security 

features of the W78 warhead have changed since the W78 entered the stockpile in 1979. The W87-1

Modification Program will meet DoD and DOE/NNSA requirements for performance, safety, and security 

and is slated to deploy on the Sentinel in the early 2030s. 

2.2.6.1 Status

Following authorization from the Nuclear Weapons Council in September 2018, the W87-1 restarted 

Phase 6.2, Feasibility Study and Design Options, in January 2019. The program completed 6.2 and entered

Phase 6.2A, Design Definition and Cost Study, in the fourth quarter of FY 2021. As of the end of FY 2022, 

the program is awaiting Nuclear Weapons Council approval to enter Phase 6.3, Development Engineering. 

DOE/NNSA previously established a W87-1 Federal program office along with the requisite staff, program 

plans, and management documents. In 2019, the Nuclear Weapons Council selected a single surety 

architecture for the W87-1, and DOE/NNSA continues to evaluate component features through feasibility 

and trade studies.

2.2.7 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 

Nuclear Weapon Phase X Life Cycle Process for integrated nuclear weapons system acquisition, rather 

than the Phase 6.X Process (see Section 2.2.1 for additional information regarding these life cycle 

processes). Work in support of the W93 Program will include Phase 1, Concept Assessment, 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. 

Carrying out the W93 program is vital for continuing DOE/NNSA’s 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. 
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2.2.7.1 Status

The W93 completed Phase 1, Concept Assessment, in the third quarter of FY 2022. The Nuclear Weapons 

Council has authorized the program to proceed into Phase 2, Feasibility Study and Design Options.

2.2.8 Future Warheads

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. 

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 5-year Dismantlement Plan balances physical constraints with legislative, policy, and 

directive guidance. The WDD work scope includes 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 make significant progress on dismantling weapons and component disposition. 

As noted in prior SSMPs, DOE/NNSA was on pace to complete the dismantlement of all warheads retired 

before FY 2009 by the end of FY 2022; however, the global Coronavirus Disease 2019 pandemic delayed 

the dismantlement of a small number of these retired warheads until after FY 2022. DOE/NNSA remains 

committed to completing this effort. In addition, DOE/NNSA has developed return schedules to remove 

retired weapons from DoD facilities while meeting DoD operational requirements. WDD continues to 

characterize components coming off the dismantlement line, and sites are eliminating excess component 

inventories.

WDD Accomplishments

Weapon Dismantlement and

Disposition team completed over 

275 arming, fuzing, and firing tear 

downs – well above the year’s goal 

of 150.
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2.4 Production Operations

Production Operations provides the base capabilities to enable 

weapon operations (assembly, disassembly, and production) 

planned for the warhead modernization, stockpile systems, and the

WDD programs. Production Operations’ goal is to maintain the base 

capability required to sustain a responsive and resilient stockpile 

through robust management and production process engineering, 

manufacturing, and production technology resources. 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 facilitates the 

capability and capacity to sustain the nuclear security enterprise’s 

production mission, mainly through sustaining and expanding the 

multi-program enabling workforce. The base labor capacity the 

program provides is essential to preventive and corrective 

maintenance, calibrations, quality assurance, qualification, 

production logistics, manufacturing execution systems, process flow, and scheduling activities. 

Production Operations also maintains critical multi-weapon system supporting equipment at certain sites 

and select programmatic infrastructure. 

Production Operations also serves as the demand signal for the modernization of production capabilities 

and capacity to improve efficiency and maintain manufacturing operations that will meet future 

requirements. The program requires close coordination with the Production Modernization and 

Advanced Manufacturing Development programs, which are charged with development and initial 

deployment of new, or replacement, manufacturing capabilities. It also heavily depends on required 

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 sustainment capacity 

to meet a significant increase in demand associated with the ramp up in warhead modernization activities 

and Production Modernization projects. 

As the Production Support program evolved into Production Operations within the Office of Stockpile 

Production Integration, it has taken on additional scope in enterprise capacity modeling and planning. 

This emerging function aligns well with Production Operations’ role as a demand signal for modernizing 

nuclear security enterprise production capability and capacity expansion.

Production Accomplishments

• Sustained base capabilities for 

multi-system operations and 

maintenance support to meet all 

LLC exchange GTS fills and 

surveillance deliverables

• KCNSC completed over 1,600 

critical equipment calibrations in 

support of production activities.

• Supported over 800 LLNL 

engineering authorizations and 350 

product realization team meetings. 

• Accepted over 130,000 SNL 

components at a 100 percent 

acceptance rate.

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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-1

Chapter 3

Weapons Activities Capabilities that 

Support the Nuclear Security Enterprise

Chapter 2 describes how the Department of Energy’s National 

Nuclear Security Administration (DOE/NNSA) fulfills the critical 

mission to assess, surveil, modernize, and qualify the nuclear 

weapons stockpile, and certify it is safe, secure, and effective. 

Chapter 3 focuses on the Weapons Activities capabilities required 

to accomplish this mission. DOE/NNSA delivers the capabilities 

required for an effective nuclear deterrent that provides the Nation 

with the ability to adapt and respond to a dynamic security 

environment, emerging strategic challenges, and geopolitical and 

technological changes. The Department of Defense (DoD) 

supplements the Weapons Activities capabilities with specific 

efforts, including platforms for flight tests.

The Weapons Activities capabilities described in this chapter 

directly support 2022 NNSA Strategic Vision Mission Priority #1, design and deliver the Nation’s nuclear 

stockpile. To accomplish this mission, DOE/NNSA must sustain the current stockpile, undertake 

comprehensive weapons modernization, recapitalize the nuclear weapons infrastructure, and strengthen 

cutting-edge science, technology, and engineering capabilities.

More than 30 key Weapons Activities capabilities support conduct of the Integrated Stockpile Model 

introduced in Chapter 1, Figure 1–2, and each capability may support multiple parts of this model. This 

interdependency between model activities and capabilities, and among the capabilities, is described 

throughout Chapter 3. Figure 3–1 shows the seven interdependent areas, previously termed portfolios, 

each containing a suite of capabilities that, combined, address a particular aspect of Weapons Activities. 

While most Weapons Activities capabilities are applicable only to the stockpile mission, many are also 

used to support nonproliferation, naval reactors, and counterterrorism activities. Examples are discussed 

throughout this chapter.

The nuclear security enterprise elements that comprise Weapons Activities capabilities are illustrated in 

Figure 3–2. These elements include the human capital, physical assets, resources, and enabling processes 

underpinning the Weapons Activities capabilities. All four elements must be sustained, modernized, and 

advanced to meet current and future missions. The capabilities cannot function as a system if any of these 

elements are missing.

Weapons Activities capabilities require periodic evaluation across all four elements to assess their health 

and continued investment. That evaluation is reflected in this chapter and continues in Chapter 4, 

“Infrastructure and Operations.” 

Key Changes to Weapons 

Activities Capabilities

• Revision of capabilities within the 

Weapon Science and Engineering 

Area to better align with 

DOE/NNSA mission-related 

activities 

• Simplification of the capabilities 

within the Weapon Material 

Processing and Manufacturing 

Area 
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Figure 3–1. DOE/NNSA Weapons Activities capability areas

Figure 3–2. Weapons Activities capability elements
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Many of the capabilities described below are unique to the nuclear security enterprise. The highly 

specialized materials, various supply chain component lot sizes, security requirements, advanced 

computing and research requirements, and stringent manufacturing specifications required for nuclear 

weapons development and production make the work difficult, or unprofitable, for commercial providers. 

DOE/NNSA must sustain the health of the Weapons Activities capabilities to continue availability of these 

niche functions. In addition, the national security requirements for nuclear weapons require trusted 

domestic vendors for certain materials and processes.

This chapter’s sections describe the Weapons Activities Capabilities areas, their constituent capabilities, 

specific support to the nuclear deterrent mission, and how they link and integrate with other areas and 

capabilities. See Chapter 4 and Appendix C for an enterprise-level overview of major infrastructure 

investments and the supporting workforce tied to Weapons Activities capabilities. In Chapter 4, 

Section 4.2.1, the programmatic infrastructure investments supporting each capability area are aligned 

with each of the sections in this chapter.

3.1 Weapon Science and Engineering Area

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 future stockpile weapons. This portfolio of capabilities is closely linked to the 

Weapon Simulation and Computing area (Section 3.2) and the Weapon Design and Integration area

(Section 3.3). Capabilities in all three areas routinely support efforts in the other two, and all three areas

are needed to deliver stockpile mission priorities of assuring an effective, resilient, and flexible nuclear 

deterrent.

3.1.1 Atomic Physics, Nuclear Physics, Nuclear Engineering, and 

Radiochemistry

Atomic, nuclear, and radiochemical properties relevant to weapons are critical to enhancing predictive 

capabilities and designing validation experiments that increase confidence in simulation models. New 

measurements and evaluations of experimental data that impact, or inform, weapon properties can 

reduce uncertainties in predictive simulations and improve reassessments of historic underground 

nuclear explosive test data used to validate and constrain weapons simulations. Reducing uncertainty is 

critical to the certification strategy for future stockpile options and assessments of the existing stockpile 

as weapons age. 

Atomic physics is the study of interactions among electrons, atomic nuclei, and photons (particularly 

X-rays). Atomic physics processes, such as X-ray generation, are relevant to the function of nuclear 

weapons. Facilities such as the National Ignition Facility (NIF), Omega Laser Facility (Omega), Los Alamos 

Neutron Science Center (LANSCE), and Z pulsed power facility (Z) provide capabilities to explore atomic 

physics processes that occur in nuclear weapons to inform, improve, and validate computational models.

Nuclear physics is the study of atomic nuclei and their constituents, while nuclear engineering is the 

translation of nuclear physics principles to the applications of nuclear interactions including fission and 

fusion. Nuclei undergo complex reaction pathways and provide a significant energy source in nuclear 

weapons, requiring accurate and precise nuclear data for stockpile performance and safety assessments. 

Nuclear forces are challenging for theoretical understanding, necessitating experimental measurements. 

Data are collected at large experimental facilities such as LANSCE, other DOE national laboratories (e.g., 

Argonne National Laboratory, Berkeley National Laboratory) and academic institutions (e.g., Texas A&M 

University, Triangle Universities Nuclear Laboratory). Integral measurements used to validate the nuclear 
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data libraries are performed at facilities such as the National Criticality Experiments Research Center at 

the Nevada National Security Site.

Radiochemistry is the study of radioactive materials and their interactions and is the basis of DOE/NNSA’s 

modern connection to legacy underground nuclear explosive test data. Radiochemical data from the 

United States’ extensive underground nuclear explosive test history database are used to inform modernday assessments of weapon performance as part of stockpile stewardship. New measurement techniques 

have enabled analysis of additional reaction products from legacy underground nuclear explosive tests, 

and the results supplement benchmarking models from those events. Radiochemistry also supports other 

scientific areas; for example, it is used to develop target materials for nuclear reaction measurements and 

it is an important element of the diagnostic capabilities used by high energy density (HED) experiments. 

DOE/NNSA is the nuclear forensics1lead for the U.S. Government and employs radiochemistry tools to 

address national security problems. 

3.1.1.1 Status

DOE/NNSA’s atomic physics understanding is strong at the limits of high and low temperatures and high 

and low densities. Between these extremes, there is uncertainty in the fundamental theories, with 

minimal benchmarked data to inform them. These uncertainties in basic properties lead to increased 

uncertainties regarding final integrated simulation outputs. A concern for future workforce development 

and growth in atomic physics is that only a small number of university programs offer relevant training.

Over the past decade, nuclear physics experiments for stockpile stewardship have increased in precision 

and complexity. New detector systems that use novel materials and modern engineering techniques are 

enabling unprecedented data precision and providing new data from competing reactions. Coupling 

nuclear theory to experiments is also expanding predictive methods toward determining nuclear 

properties for radioactive materials that are difficult to measure. Support for fast neutron facilities 

(> 0.1 MeV) remains imperative, as reaction product measurements provide additional accuracy for 

nuclear data and code validation. 

Nuclear data evaluation is an established methodology that requires high-quality measurements coupled 

with theoretical reaction calculations to improve predictive simulations. Data evaluators reconcile newly 

acquired measurements with existing data and physics models to determine “best value” quantities and 

uncertainties. Significant investment in training evaluators is essential to providing long-term support to 

the nuclear data pipeline. 

The key radiochemical facilities across the nuclear security enterprise are in high demand, but they are 

aging. Some urgent infrastructure needs have been addressed, but additional recapitalization is required 

to obtain measurements for evaluating legacy test data, modern HED experiments, and nuclear data 

collection. 

Many personnel with the knowledge, skills, and abilities in this specialized field have retired, resulting in 

knowledge gaps about historical methods. Qualified radiochemists must have specialized knowledge and 

hands-on laboratory training. While the number of radiochemistry programs at universities has increased, 

most programs do not address the specific needs of the nuclear security enterprise, necessitating training 

and knowledge transfer between existing employees and new hires. 

1 For further information on DOE/NNSA’s nuclear forensics work, refer to NNSA Prevent, Counter and Respond – NNSA’S Plan to 

Reduce Global Nuclear Threats.
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3.1.2 Materials Science, Chemistry, High Explosives and Energetics 

Science and Engineering, and Actinide Science

The Materials Science and Engineering capability aids in understanding how all the materials in a nuclear 

weapon system perform in diverse and extreme environments throughout its entire life cycle. This 

capability plays a key role in resolving stockpile and production issues, validating computational models, 

and developing new materials (e.g., materials produced through advanced manufacturing or designed to 

replace environmentally hazardous and/or difficult to manufacture legacy materials). In addition, 

Materials Science and Engineering experiments contribute to stockpile surveillance, where the effects of 

aging materials must be detected and evaluated to support the stockpile annual assessment. When 

materials used in the stockpile must be replaced due to aging issues or obsolescence, new materials are 

developed, studied, and certified for insertion into the stockpile and are vital to extending weapon 

systems’ life. The qualification of new or replacement materials reduces risks and may improve the overall 

safety and reliability of the stockpile. 

Within the Materials Science and Engineering capability, dynamic material studies investigate the 

compressive behavior, structural transformations, deformation, fracture, and chemical reactions that 

occur in materials subject to impulsive loading. Experimental investigations of the static properties and 

dynamic response of stockpile materials in relevant regimes requires specialized facilities such as NIF, Z, 

LANSCE, Joint Actinide Shock Physics Experimental Research, and Technical Area 55 (TA-55) gas gun 

facilities. The data generated from these studies is used to create and validate material physics models

that contribute to a confident prediction of weapon performance and is increasingly being used for 

material replacement decisions and to define requirements for components qualification.

The High Explosives and Energetics Science and Engineering capability is the study of detonation and 

deflagration physics, shock wave propagation, and reaction initiation. It includes the study of the design, 

synthesis, manufacture, inspection, testing, and evaluation of high explosives (HE) and other energetic 

materials and components for specific applications. Knowledge of HE and energetic materials is crucial to 

understand nuclear weapon safety and performance.

These areas are structured to address challenges and meet weapon delivery schedules.

The Chemistry and Chemical Engineering capability encompasses the study of the fundamental 

composition, structure, bonding, and reactivity of matter in a given state and under processing conditions. 

This capability plays a key role in the design and improvement of manufacturing processes for weapon 

components. It is essential for synthesizing, purifying, processing, and fabricating all of the materials that 

are currently fielded in stockpile warheads, and it is critical for resolving stockpile surveillance issues. It is 

also necessary for developing and qualifying new materials proposed for near-term warhead 

modernizations and future system requirements. This capability supports experimental testing and 

computational tools that help to understand the chemical reactions that control material creation and 

compatibility as well as the mechanisms and effects of aging and degradation to ensure the quality, 

performance, and safety of the current stockpile.

Actinide science is the study of physics and chemistry of elements from actinium to lawrencium. This 

science is important to the understanding of production, purification, compatibility, targets, and behavior 

of actinide materials relevant to the stockpile. Overall, the nuclear security enterprise workforce meets

mission needs related to capabilities across materials science, chemistry, and actinide science, and these 

capabilities come together in support of mission priorities such as new pit production. 
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3.1.2.1 Status

Materials science efforts across the nuclear security enterprise have yielded important results in 

characterizing current stockpile materials under extreme conditions. This capability is strengthened by 

expanded experimental and computational investigations and enhanced collaborations among 

DOE/NNSA national security laboratories and nuclear weapons production facilities, sites with 

experimental platforms, and networks with strategic academic partners.

DOE/NNSA performs Materials Science and Engineering experiments using a broad range of research and 

development (R&D), testing, and evaluation facilities. Experimental facilities are supported by fabrication 

capabilities in the complex and with industrial partners. Several new materials and increased scrutiny of 

how legacy materials change with age are putting significant strain on throughput at existing facilities. 

The current capability’s scope presents challenges in maintaining an expert workforce and sustaining 

modern facilities. Developing a sustainable workforce requires active partnering with academic 

institutions and industry. Furthermore, onboarding that allows significant training time in specialized 

areas, and stable investments in programs that support foundational applied sciences, are required. Some 

facilities, such as upgraded plutonium facilities, the new Uranium Processing Facility, and renovated 

radiological space, have received major capital investments for replacement. Future investments are 

needed for the new lithium facility, as well as modernized laboratory space to house radiological and 

general chemical synthesis.

Meeting current and future challenges requires continued investments in sustaining DOE/NNSA’s existing 

infrastructure and capabilities while transforming relevant infrastructure to be responsive and agile. 

DOE/NNSA has the Energetic Materials Characterization project underway and plans to recapitalize 

additional HE facilities to meet these challenges, including the HE Applications Facility, Site 300, and the 

National Energetic and Engineering Weapons Campus, including the Detonator Production Facility.

Several key actinide science facilities across the nuclear security enterprise are in high demand, but they 

are aging. Some urgent infrastructure needs have been addressed, but additional recapitalization in 

facilities and key equipment such as accelerators is required to obtain fundamental actinide science 

material properties measurements, to perform evaluations supporting efficiencies in manufacturing, and 

to interpret legacy underground nuclear explosive tests. 

Many personnel with the knowledge, skills, and abilities in this specialized field have retired, creating

knowledge gaps about historical methods. Qualified actinide scientists must have specialized knowledge 

and hands-on laboratory training. While the number of actinide science programs at universities has 

increased, most programs do not address the nuclear security enterprise’s specific needs, necessitating 

training and knowledge transfer between existing employees and new hires.

3.1.3 High Energy Density Science and Plasma Physics

HED Science includes the study of matter and radiation under extreme conditions, including the conditions 

produced in a functioning nuclear weapon. HED experiments provide data required to validate weapon 

physics models in simulations tools used to assess the stockpile. Focused and integrated HED experiments 

provide the data needed to support warhead certification for legacy and new weapon systems. Inertial 

Confinement Fusion (ICF) experiments use the extreme conditions of HED states to generate fusion 

reactions and further expand the range of conditions accessible in the laboratory. HED experiments 

support scientists’ development and their judgement on weapons-related issues and promote the 

development of skills in experimentation, design work, fabrication, instrumentation, and other related 

areas.
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ICF experiments compress and fuse light hydrogenic 

species (deuterium and tritium), releasing large quantities 

of energy and neutrons. The design and analysis of these 

experiments builds understanding of thermonuclear burn 

and plasma properties, while also providing a driver for the 

development of new cutting-edge technologies in multiple 

fields. The generation of mega-joule yields at the NIF 

provides a first-of-its-kind capability across the globe to 

experimentally measure unique temperature, pressure, 

and density conditions. Understanding the physics of 

higher yield ICF platforms and exploring the boundaries of 

what is possible are key goals for HED Science.

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 HED states producing data exploring the 

physical processes that occur in plasma states to validate computational models and improve 

understanding of matter under HED conditions.

3.1.3.1 Status

Across all three major HED facilities (NIF, Z, and Omega), experimental platforms have produced

important data relevant to the performance and stewardship of nuclear weapons. HED facilities have also 

enabled important advances in determining plutonium properties at relevant pressures and in addressing 

key questions on aging and remanufacturing. These advances provide immediate mission support in 

predictive nuclear weapon performance and are crucial to advancing simulation capabilities in energy 

densities of interest. 

One challenge facing the HED and ICF capability is achieving 

a robust burning fusion plasma, which is the key to enabling 

technology required to significantly shrink the gap between 

laboratory experiments and weapons environments. The 

understanding developed through each stage of 

experimental performance along the path to a robust 

burning fusion plasma provides key knowledge and 

constraining data for simulations, and access to material 

properties and outputs unachievable anywhere else in the 

world. In recent years, a focused effort on understanding 

and scaling all the major HED science platforms will establish 

a foundation for next-step decisions on investments and program balance needed to realize long-term 

stockpile goals for a modern, flexible, responsive, and resilient deterrent.

The workforce of scientists with training in plasma physics has become stronger over the last decade. A 

concern for future workforce development and growth is that only a small number of university programs 

offer relevant training, though several of these institutions are offering these courses online to reach a 

broader academic community. 

The National Ignition Facility conducted a HED 

experiment using the first-ever shot with explosives.

NIF, the world’s most energetic laser, 

conducted the first-ever shot to study a HE

sample. The results from the shot will help 

researchers unlock the mysteries of HE by 

providing experimental data that quantifies the 

response of laser-driven HE during reaction.

The shot used a non-detonable quantity of an 

insensitive HE that is used as the main charges 

in weapons systems.

Using HE material at NIF, a radiological facility, 

required careful analysis and preparation. As 

with other hazardous or radioactive materials, 

NIF had to develop and implement rigid, formal 

operational protocols to ensure that the highexplosive experiments would be conducted 

safely and within NIF’s authorized limits of 

operation.
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3.1.4 Technologies to Study Extreme Conditions (Lasers, Accelerators, 

and Pulsed Power)

DOE/NNSA uses lasers, accelerators, and pulsed power capabilities to support the stockpile in several 

ways: (1) generating stockpile-relevant environments to qualify materials, components, systems, and 

hardened electronics in hostile environments; (2) providing static and dynamic material information for 

weapon assemblies and components that can inform predictive capabilities; and (3) exploring and 

implementing new options for the stockpile as external threats evolve.

Lasers and pulsed-power machines deliver intense pulses of energy into microscopic volumes. Within the 

nuclear security enterprise, these capabilities are used to generate and probe HED conditions similar to 

those produced when a nuclear weapon is detonated. These technologies support studies that affect 

design codes enhancement, new components and systems qualification, and improvement of weapon 

performance assessments. Experiments on the various facilities directly inform material choices for 

warhead modernizations and resolve stockpile questions. 

Laser-driven facilities such as NIF and Omega are complemented by pulsed-power facilitiessuch as Z; they

provide important complementary HED data as well as unique HED conditions with distinct characteristics. 

The combined capabilities from these two approaches to producing HED conditions work together to 

generate a spectrum of material and physics regimes needed to study the environments’ experiences by 

nuclear weapons upon detonation, including components and materials aging, weapon-relevant materials 

performance under hostile environments, and components and systems survivability.

Accelerator technology supports the stockpile by providing high-fidelity static and dynamic material 

information for weapon assemblies and components, imaging subcritical experiments in real time, and 

providing unique high-energy particle beams for various other activities. Accelerator technology uses 

high-voltage pulsed powerto accelerate charged particles to generate high-energy X-rays, protons, and/or 

neutrons that probe objects in weapon-relevant experiments. These pulses of high-energy particles can 

also be used as a radiographic source for dynamic imaging diagnostics. Accelerator technology is a critical 

component of the Scorpius project at the U1a Complex (U1a), the Dual-Axis Radiographic Hydrodynamic 

Test facility (DARHT), the Flash X-Ray capability at the Contained Firing Facility (CFF), and LANSCE. 

3.1.4.1 Status

Over the past decade, U.S. HED facilities have achieved unprecedented levels of performance and 

efficiency. Maintaining and enhancing this capability as equipment and facilities reach their intended 

service lifetime is a challenge. The NIF, Z, and Omega facilities are reaching a point where some 

subsystems and components are reaching obsolescence, and locating suitable replacements and vendors,

is becoming an issue. Recapitalizing these facilities and equipment with minimal pause in operations will 

be necessary to sustain a key role in maintaining a strong deterrent.

Today, pulsed power accelerator technology is employed to generate data needed to qualify weapon 

components and assess weapon performance, which was formerly only possible via underground nuclear 

explosive tests. The Nation’s accelerator and pulsed power facilities are aging (e.g., CFF/Flash X-Ray,

DARHT, and LANSCE), and cannot provide the full range of test capabilities needed to assure the future 

viability and reliability of the stockpile. These test capabilities include a combination of the environments 

that weapons may experience during use. 

Additionally, accelerator facilities such as LANSCE are essential to the ability to probe the characteristics 

and performance of materials for the evolving deterrent. The front end of the LANSCE accelerator is 

50 years old and based on technology that is nearly a century old. Further, many of the LANSCE 

components are reaching obsolescence and becoming increasingly challenging to maintain. 
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Modernization of LANSCE and investments in national light source facilities tailored to stockpile 

applications would support obtaining the material and nuclear science data needed for the deterrent.

3.1.5 Advanced Experimental Diagnostics and Sensors

The Advanced Experimental Diagnostics and Sensors capability provides the technology to make detailed 

measurements of materials, objects, components, system assemblies, and dynamic processes that are 

critical to weapon performance, other national security applications, and HED science. The data are vital 

to understanding material and system behavior across requisite environments and in the extreme 

conditions reached in nuclear weapons. For dynamic material experiments, new diagnostics provide data 

vital to understanding material behavior in the extreme conditions reached in nuclear weapons. In the 

HED field, advanced diagnostics are necessary to improve understanding of weapon science experiments 

and implosions, and to acquire the high-fidelity data required to validate aspects of stockpile stewardship 

computational capabilities. As HED facilities increase yields, additional diagnostics must be developed to 

operate at higher yields and study plasma behavior achieved in the laboratory. The breadth of 

experiments performed at Hydrodynamic and Subcritical Experiments (HSE) facilities is increasing and 

developing a broader range of higher performance diagnostics is key to generating high-quality data for 

the weapons programs.

Diagnostic development activities are linked closely to other enterprise mission needs, and individual 

diagnostic requirements can vary drastically. Time scales can vary from microseconds to picoseconds and 

length scales can vary from meters to microns. Different technologies need to be developed to investigate

this wide range of parameters. Accurate diagnostic measurements of shocked material experiments and 

HED science experiments are critical to constrain the simulations used to underwrite the nuclear stockpile.

3.1.5.1 Status

DOE/NNSA has developed transformative, next-generation diagnostics across weapons science and 

engineering capabilities. These diagnostic capabilities now contribute to a better understanding of 

weapon performance, including the dynamic materials and components response in relevant weapon 

environments. This response has led to new insights on plutonium aging and is being used to improve 

models that inform plutonium lifetime assessments. Advances in diagnostics have also enabled recent 

experiments to determine the effects of new manufacturing processes for components in future warhead 

systems. With these new techniques, uncertainties can be reduced, and more informed decisions can be 

made when changes to the stockpile are needed. However, a broader range of higher performance 

diagnostics are still needed to address the increasing breadth of experiments and provide high-quality 

data for the weapons programs.

As HED facilities increase yields, new diagnostics must be developed to study new plasma conditions that 

are being created in the laboratory. Higher fidelity diagnostic measurements, improved calibration 

capabilities, and new techniques must also be developed to obtain higher spatial and time resolution to 

better understand the evolution of implosion and shock-driven phenomena. In order to meet these 

challenges, a National Diagnostics Working Group of over 100 scientists from Lawrence Livermore 

National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratories

(SNL), together with national laboratory and academic partners Lawrence Berkeley National Laboratory, 

the Laboratory for Laser Energetics at the University of Rochester, and the Massachusetts Institute of 

Technology), meet annually to develop and implement multi-year plans to develop advanced diagnostics.

Continual improvement of experimental diagnostics and sensors is an enduring need to ensure advances 

in stockpile science and drive down and quantify simulation uncertainties. Experimental diagnostics also 

push the boundary of what is possible and inspire concepts for future experimental advances. To support 
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this, DOE/NNSA continues to invest in four areas: (1) infrastructure to support the continued health of 

existing diagnostics; (2) hiring and training the next generation of diagnostic scientists who will push the 

frontier of measurement science; (3) supporting the supply chain of specialized equipment uniquely 

required for HED and HSE diagnostics; and (4) development of advanced and transformational diagnostics.

3.1.6 Hydrodynamic and Subcritical Experiments

The HSE capability provides data on the behavior of imploding primaries without creating nuclear yield, 

providing vital data on material behavior under low energy density extreme conditions. The combination 

of hydrodynamic testing with surrogate materials and subcritical experiments with plutonium provides 

important data to build and validate weapon design and safety simulation capabilities. 

HSE are used to characterize nuclear weapons’ primary performance and safety and to assess the effects 

of findings from stockpile surveillance. The data are used for the stockpile annual assessment and 

certification decisions before a weapon enters the stockpile. These experiments are also used to assess 

the effects of aging components and their potential replacements in warhead modernizations and effects 

on weapon performance and potential design changes, material substitution, and component changes. 

3.1.6.1 Status

The National Hydrodynamic Testing Complex consists of open-air, contained, and underground facilities 

at several NNSA sites to provide the experimental infrastructure for hydrodynamic and subcritical 

experiments. These specialized facilities are operating at near capacity and the complex is aging. The

demand for a higher cadence of experimental data collection required by multiple DOE/NNSA programs 

stresses the physical infrastructure and the workforce. Additional investments would allow DOE/NNSA to

meet a greater demand and to maintain the equipment, facilities, and people underpinning this capability.

The weapon programs supported by the HSE capability require more and higher-resolution data, 

necessitating increased testing and enhanced or novel diagnostic measurements. Higher-resolution data 

are needed to validate higher-fidelity, more-predictive computational simulation capabilities used to 

certify primaries without underground nuclear explosive tests. Because of the high-hazard nature of these 

integrated experiments, programmatic needs must be met while ensuring the protection of DOE/NNSA’s 

staff, the environment, and the public.

A new, more capable accelerator is being developed for the Enhanced Capabilities for Subcritical 

Experiments (ECSE) project to deliver images showing the final implosion stages of plutonium, which

currently is not possible using existing radiographic capabilities. Complementary neutron diagnostic 

capabilities are also being developed as part of the ECSE project for deployment in underground subcritical 

experiments.

The U1a Complex Enhancements Project provides the U1a with the infrastructure to house and field multipulse radiography and reactivity diagnostics to support ECSE. This project includes the structures, 

systems, and components necessary for deploying the ECSE Advanced Sources and Detectors Project’s 

pulsed X-ray radiography equipment and future neutron diagnosed subcritical experiments technology 

that will provide valuable data on the phenomena associated with the final stages of a weapon implosion. 

Future advanced radiographic concepts actively under development include cinematographic radiography 

(“X-Ray movies”) for a potential second axis at the CFF or upgrade to DARHT axis-1. Additional HSE 

capabilities under development include a multi-axis tomographic system based on laser radiography. 

Both would deliver enhanced capabilities enabling a responsive assessment of the current stockpile and 

certification of future systems. 
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3.1.7 Challenges and Strategies

Table 3–1 provides a high-level summary of the Weapon Science and Engineering area challenges and the 

strategies to address them.

Table 3–1. Summary of the Weapon Science and Engineering area challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

All

Developing a robust and diverse 

workforce trained for the foundational 

and applied research requisite to 

DOE/NNSA missions.

Continue current hiring and 

recruitment efforts to provide 

opportunities for students. Maintain 

academic alliances in all capability

areas to address current workforce 

attrition. Continue student internship 

programs at the national laboratories.

Provide new opportunities for students 

through increased academic fellowships 

and grant programs; build new academic 

alliances in all capability areas to develop 

next generation of workforce. Conduct 

workshops and other similar mechanisms 

to facilitate knowledge transfer and close 

gaps caused by the absence of ongoing 

underground nuclear explosive tests. 

Address the specialized knowledge and 

experimental skill sets required for the 

modern workforce through focused 

training programs. Develop small-scale 

technology demonstration systems as 

platforms to engage and recruit the next 

generation of stockpile stewards.

Maintaining reliable operations in aging 

facilities where infrastructure and 

capital equipment are becoming difficult 

to repair or replace due to 

obsolescence.

Execute near-term capital and 

incremental improvements for facility 

upgrades and replacements to 

maximize impact on stockpile 

programs. Reduce deferred 

maintenance and develop conceptual 

plans for future experimental facilities. 

Prioritize current investments for key 

equipment. Use working groups to 

evaluate existing experimental gaps 

and plan and develop new 

experimental facility capabilities. 

Modernize facilities and equipment and 

develop more capable experimental 

platforms to support U.S. preeminence in 

science. Develop long-term investment 

strategies across the Weapon Science 

area to address capital planning and 

mitigate facility aging issues through 

upgrades or replacements. Work to 

expand current U.S. vendor base to 

develop replacements for obsolete 

components. Prioritize strategic 

investments in key equipment.

Resolving inconsistencies among data 

and physics models, certain processes,

and properties of materials of interest 

to increase certainty in simulated 

outputs

Test accuracy of current complex 

models with experimental 

measurements.

Extend state-of-the art complex models 

to produce more complete and consistent 

data sets. Develop multi-platform 

experimental capabilities to validate 

complex models across the entire range 

of conditions.

Atomic Physics, Nuclear Physics, Nuclear Engineering, and Radiochemistry

Addressing uncertainty in the behavior 

of matter between low and high 

temperature to enhance certainty in 

simulated outputs.

Continue advancing fundamental 

theoretical and experimental research 

at universities and national 

laboratories to reduce and quantify 

uncertainties.

Develop new and innovative 

experimental platforms with existing

capabilities.

Generating sufficient benchmark data to

verify certain phenomena that will

increase certainty in simulated outputs.

Continue developing and maintaining

current experimental platforms to 

collect data on the properties of high 

atomic number and mixed materials 

(e.g., opacity, high-pressure material 

properties, conductivities, and 

radiative response).

Develop new capabilities and 

experimental platforms that close existing 

gaps to verifying the properties of high 

atomic number and mixed materials (e.g., 

opacity, high-pressure material 

properties, conductivities, and radiative 

response).
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Increasing demand on computational 

capacity and capability to run complex 

radiation models.

Continue developing new 

computational tools and optimizing 

models and algorithms for new 

computing architectures, leveraging 

simulation, codes, and HPC 

capabilities.

Evaluate the long-term need and balance 

of high-performance vs high-capacity 

computing investments and prioritize 

more capacity computing if needed. 

Develop more efficient and integrated 

workflows to share computational 

resources across the national 

laboratories.

Addressing uncertainties in nuclear data 

and developing new experimental 

nuclear science capabilities.

Continue conducting fundamental 

theoretical and experimental research 

at universities and national 

laboratories on nuclear data that can

reduce uncertainties.

Develop new and innovate experimental 

capabilities.

Adequately preserving and cataloguing 

radiochemical data from historical 

nuclear tests to improve access, creating 

searchable databases that are easily 

accessible across weapon laboratories.

Continue current efforts to scan and 

catalogue all data.

Develop new ways to improve archiving 

and cataloguing all data and improve data 

management systems’ function and 

access.

Materials Science, Chemistry, and Actinide Science

Maintaining and enhancing the ability to 

assess and qualify material changes in a 

timely and cost-effective manner, driven 

by needs associated with aging, 

manufacturing, obsolescence, and 

replacement for hazard mitigation in a 

timely and cost-effective manner. 

Access to the required experimental 

capabilities will require recapitalization 

and modernization investments at 

LANSCE and investments in tailored 

functionality at light sources.

Continue R&D in the manufacturing 

science foundation to predict the 

effect of material changes (e.g., 

process, microstructure, and/or 

impurities) on the material properties 

affecting performance to accelerate 

qualification. Develop new 

experimental techniques to 

dynamically probe bulk material 

performance in the mesoscale regime. 

Use existing experimental platforms 

and explore the benefits and 

opportunities of developing new 

platforms.

Expand experimental and computational 

abilities that enable more detailed studies 

of material changes and new material 

design, enable more rapid qualification 

through partnerships between national 

security laboratories and nuclear 

weapons production facilities, and deliver 

solutions to emerging materials issues. 

Meeting the high demand for dynamic 

materials properties data to support 

warhead modernizations and science 

programs and in-situ diagnostics.

Continue research on existing material 

science and engineering tools. Use 

expert cross-functional teams to 

prioritize using unique capabilities 

such as plutonium-capable gun 

facilities. Invest in material and target 

preparation capabilities and deconflict 

resources.

Continue the current strategy and 

develop new cutting-edge material 

science and engineering tools that will 

attract the nuclear security enterprise’s 

next generation workforce. Build and 

sustain pipeline networks with U.S. 

academic institutes. 

Responding to emerging weapons 

program needs for main charge 

explosives using expertise and other 

capability aspects that have not been 

exercised in recent years.

Exercise the physics laboratory science 

and engineering HE development 

process to achieve higher technology 

readiness levels. Collaborate with DoD 

and industrial partners to produce HE 

and preserve in-house production 

authority, such as for WR detonator 

powder production.

Develop new strategies for HE 

development processes with goals 

reflecting future program requirements.

Improving HE safety by bringing the 

state of the prediction capability in line 

with HE performance prediction.

Continue to understand and predict HE 

deflagration through a combination of 

bench-scale and full-scale 

experimentation.

Develop combined new experimental and 

simulation capabilities to fully address the 

physical and mesoscale behaviors 

influencing safety considerations.
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-13

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Predicting chemical compatibility in new 

systems to reduce the need for 

expensive core-stack and shelf-life units.

Continue to develop and validate 

computational chemistry models to 

understand chemical compatibility.

Develop and validate new computational 

chemistry models that span length and 

time scales and address reactivity at 

interfaces.

Eliminating capability gaps in weapons 

analytical chemistry and actinide 

science as DOE/NNSA increases pit 

production activities.

Simultaneously execute WR analytical 

technique qualification and the 

Chemistry and Metallurgy Research 

facility exit strategy.

Develop new strategies to reduce 

capability gaps in weapons analytical 

chemistry and actinide science.

Scaling up new material formulations 

from the laboratory to industry to 

provide required materials from 

commercial material sources.

Continue to partner across the nuclear 

security enterprise to transition from 

large numbers of small-scale 

experiments to fewer informed pilotscale tests.

Develop new partnerships and focused 

research programs on new material 

formulations scalability.

Improving the ability to predict the 

aging effects on components.

Continue advancing multiscale, 

validated predictive models of material 

aging, including the kinetic and 

thermodynamically aware degradation 

models of organics, inorganics, 

energetics, and corrosion of metals.

Continue nondestructive tools 

development and deployment to 

assess the state of materials in service.

Develop new capabilities for predictive 

models of material aging.

Improve the use of data informatics and 

artificial intelligence to aid in

interpretating large data sets (e.g., mass 

spectrum data from compatibility and 

surveillance testing).

Develop and deploy new and 

complementary nondestructive tools to 

assess the state of materials in service.

Understanding the effects of processing 

conditions on production consistency 

and device performance.

Use existing analytical and diagnostic 

tools combined with process modeling 

to introduce efficiencies in 

manufacturing.

Provide new advanced analytical and 

diagnostic tools for inline monitoring of 

manufacturing.

Improving flexibility in the current and 

future stockpile through accelerated 

qualification methodologies using 

advanced and additive manufacturing 

techniques.

Continue research to synthesize new 

formulations that expand material 

possibilities for designing new 

composite, multifunctional materials.

Synthesize new formulations and build 

confidence in a prediction capability 

enabling materials made by new 

processes to become stable over time.

Successfully collaborate with design and 

production agencies to design for 

manufacturing.

High Energy Density Science and Plasma Physics

Accessing more weapon relevant ICF

regimes for stockpile applications.

Prioritize the fielding of experimental 

campaigns to address open weapons 

physics questions and hostile 

environments on existing HED 

facilities. Develop diagnostics that 

provide constraining data for these 

challenges. Recapitalize and 

modernize existing HED facilities.

Deliver higher fusion yield HED platforms 

to answer weapons physics questions and 

produce higher fidelity hostile 

environments needed for quantification 

assessments with accompanying 

diagnostics to deliver constraining data. 

Improve computational modeling of 

hostile environments based on data 

acquired and assess gaps in capabilities to 

support future facility investments.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Accurately predicting the performance 

of HED science targets to develop and 

deliver robust and repeatable burning 

plasma2 and ignition platforms.

Execute experiments at the HED 

facilities to characterize fusion 

phenomena, then use the results to 

enhance predictive modeling 

capabilities and understanding of 

scaling to next-generation capabilities. 

Acquire high-fidelity data and improve 

physics and modeling fidelity to 

validate 3D models. 

Understand the physics and scaling for 

the balanced development of nextgeneration capabilities leading to future 

high-yield platforms.

Accurately understanding the 

uncertainty in matter’s behavior in highmagnetic field and plasma regimes as it 

pertains to simulated outputs.

Continue conducting fundamental 

theoretical and experimental research 

at universities and national 

laboratories to reduce uncertainties.

Develop new and innovate experimental 

capabilities.

Resolve inconsistency among tabulated 

plasma data for certain properties of

interested materials to increase 

certainty in simulated outputs.

Test accuracy of current complex 

models with experimental 

measurements. 

Extend state-of-the art complex models, 

and test accuracy with experimental 

measurements. Improve underlying 

physics understanding, resulting in 

improved model accuracy. 

Technologies to Study Extreme Conditions (Lasers, Accelerators, and Pulsed Power Technology)

Waning U.S. preeminence in pulsed 

power, laser, and optical science, 

technologies, and facilities.

Execute current research plans for 

laser technology domestic 

development for the next generation, 

including advanced probe and 

radiography techniques and alternate 

light sources, to maintain U.S. 

leadership in this discipline Develop 

less expensive, more efficient, more 

reliable, more flexible, and more 

capable pulsed power architectures for 

next generation demonstration 

systems and improve current 

capabilities. Continue to develop and 

explore innovative methods to employ 

pulsed power technology for national 

security applications.

Develop future research plans to maintain 

U.S. leadership in this discipline. Develop

next-generation laser and pulsed power 

capabilities that advance the state-of-theart and attract the world-class scientists.

Generating the necessary experimental 

conditions and environments to validate 

weapons codes for the full nuclear 

weapon life cycle.

Increase investments in laser, driver, 

and accelerator technology R&D to 

extend the capability of existing 

facilities and design new facilities to 

produce higher-fidelity, weaponsrelevant environments

Prioritize investments and plans in new 

facilities and extension of current facilities 

to close mission gaps.

Advancing accelerator technologies to 

provide the necessary time-evolution 

data for experiments of interest to the 

stockpile.

Execute current research plans to 

improve higher spatial and temporal 

resolutions.

Develop new multiple-pulse technologies 

that support diagnostic techniques to 

probe data at higher spatial and temporal 

resolutions.

2 Burning plasma – A burning plasma is one in which most of the plasma heating comes from fusion reactions involving thermal 

plasma ions. A plasma enters the burning plasma regime when the self-heating power exceeds any external heating.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Advanced Experimental Diagnostics and Sensors

Developing better (higher spatial and 

time resolution) and novel diagnostic 

measurements and techniques to 

decrease simulation uncertainties and 

challenge physical models in the codes.

Maintain current experimental 

diagnostic systems. Evaluate 

measurement needs in the 5-year 

horizon, determine gaps between 

current capabilities and needed future 

development efforts. Develop and 

execute the National Diagnostic Plan 

for ICF, and an Integrated Plan for HED 

experimental diagnostics.

Develop and implement plans for 

hardening existing diagnostics so they 

can be fielded in more extreme 

nuclear and radiation environments.

Develop new world-class radiographic 

and neutron diagnostic capabilities, 

including proton radiography, X-ray 

diffraction, and advanced temperature 

diagnostics. Continuously monitor 

changing gaps in measurement capability 

and simulation need. Develop a forwardlooking diagnostic strategy for a future 

high-yield facility.

Hydrodynamic and Subcritical Experiments

Obtaining multi-frame penetrating 

radiographs on hydrodynamic 

experiments with plutonium pits.

Design, build, and install a novel 

radiographic to close ESCE capability 

gaps in the mid-2020s.

Continue to closely monitor ECSE 

program execution. Develop future 

strategies for new HSE capabilities.

Measuring the reactivity of subcritical 

assemblies on the experiments.

Implement neutron-diagnosed 

subcritical experiments in the early to 

mid-2020s.

Develop photofission methodology to 

combine neutron reactivity measurement

with radiography.

Quickly obtaining the necessary 

experimental higher cadence operation 

and time delivery of hydrodynamic and 

subcritical data needed to support 

stockpile and certification activities in a 

timely manner.

Execute current program plans for

facility enhancements to provide 

increased experimental capacity and 

operational efficiency.

Increase staffing and future investments 

in facility enhancements. 

Designing and procuring new 

confinement vessels at all firing facilities 

as existing vessels exceed useful life.

Continue to use vessels and execute 

current program plans.

Establish an enduring vessel capability 

and procurement funding strategy with 

the intention to reestablish a domestic 

fabrication and manufacturing capability 

for vessels.

The operational issues associated with 

the increased capabilities for and 

cadence of subcritical experiments at 

the NNSS U1a site are challenging.

Support yet to be developed National 

plans to address these operational 

issues.

Complete long-term planning for 

experimental capabilities at U1a, which 

support the data necessary to underpin 

the evolving deterrent.

3D = three dimensional

ECSE = Enhanced Capabilities for Subcritical Experiments

HE = high explosives

HED = high energy density

HPC = high performance computing

HSE = Hydrodynamic and Subcritical Experiments

ICF = inertial confinement fusion

LANSCE = Los Alamos Neutron Science Center

R&D = research and development

WR = War Reserve

a The term “mesoscale” refers to the properties and behaviors of materials between the atomic and macro scales. At this 

scale, a material’s structure strongly influences macroscopic behaviors and properties.
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3.2 Weapon Simulation and Computing Area

The Weapon Simulation and Computing area includes high-performance computers, weapons codes, 

models, and data analytics used to assess nuclear weapons and components’ behavior. It must calculate 

with sufficient resolution and complexity to simulate and assess weapon systems, components, and 

fundamental science processes that are critical to nuclear weapon performance. The Weapon Simulation 

and Computing area is closely linked with the Weapon Design and Integration area (Section 3.6) and 

Weapon Science and Engineering area (Section 3.7) in an iterative fashion, such that capabilities in all 

three areas are routinely supporting efforts in the other two.

3.2.1 High Performance Computing

High performance computing (HPC) involves software, 

hardware, and facilities with sufficient capability and 

power to achieve the dimensionality, resolution, and 

complexity in simulation codes to accurately model the 

weapon systems and components’ performance and the 

fundamental physical processes critical to nuclear 

operation. It also includes R&D in computer architecture 

design and engineering, data management and analytics, 

and mathematical sciences to support developing and 

operating the HPC systems. 

For DOE/NNSA, a HPC platform means an integrated 

system of hardware and software that comprehensively 

provides the required computing environment, classified 

and/or unclassified, in which a weapon analyst or 

designer can run simulations and analyze results. It is not 

just a computer, it is a host of hardware and software 

components (e.g., compute and login nodes, networks, 

file systems, long-term storage, operating systems, 

compilers, numerical libraries, developer tools, etc.), 

often developed independently from one another by 

component vendors and deployed by the HPC system 

integrator.

3.2.1.1 Status

As detail levels increase in simulation codes, especially 

those with three-dimensional features, run times to reach 

solution increase dramatically. These heightened run 

times present an increasing challenge in providing mission 

and experimental needs support in a timely fashion. 

DOE/NNSA continues to follow its clearly defined strategy 

of upgrading HPC platforms at regular intervals to address 

this challenge. This platform strategy is built around 

deploying a set of platforms that strike a careful balance among delivering reliable production cycles, 

pushing the boundaries of current technology, and looking beyond the horizon to what is coming next. 

This approach to balanced risk has served DOE/NNSA well over the previous decades. As a result, the 

Weapon Simulation and Computing area will retain the Commodity Technology Systems, Advanced 

Commodity Technology Systems

Commodity Technology Systems are workhorse 

production, general-purpose systems that provide 

stable computing power to the nuclear security 

enterprise’s design and analysis community 

through deployments at each of the three 

laboratories. These systems run the tri-lab 

software stack and persistent common software 

environment, with capability for back-up, data 

recovery, and remote mission continuation in case 

any of the NNSA labs’ computing centers become 

unavailable for an extended period.

Advanced Technology Systems

Advanced Technology Systems represent the 

most significant investments for the Advanced 

Simulation and Computing (ASC) program in 

simulation capability. These are leading-edge 

architectures that are capable of solving the most 

demanding simulations in DOE/NNSA’s mission. 

They incorporate newer technologies that push 

the limits of the ASC program in terms of facility 

requirements, software infrastructure, and 

applications. 

Advanced Architecture Prototype Systems

Advanced Architecture Prototype Systems consist 

of node-level testbeds, system-level prototypes, 

and pre-commercial hardware/scaled-up systems. 

The goal of these prototype systems is to reduce 

the risk in deploying unproven technologies by 

identifying gaps in the hardware and software 

ecosystem and making focused investments to 

address them moving from small-scale testbeds to 

potentially large-scale systems production 

computing.
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Technology Systems, and Advanced Architecture Prototype Systems in its platform strategy. All these 

systems are focused on delivering production computing cycles to the DOE/NNSA 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 grow computing capacity. In addition to using heterogeneous architectures, the 

computing industry has evolved new technology models that are more energy efficient. They have also

developed artificial intelligence and cognitive simulation capabilities and infrastructure that greatly 

magnify traditional simulation’s capabilities. An integrated approach is key to incorporating advanced 

technology innovations to support the future mission. Artificial intelligence technologies, for example, 

have the potential to transform all aspects of this area through coordinated code and platform evolution. 

Quantum computing,

3 which is even more forward-looking, could have a similar effect but will require 

more focused attention from DOE/NNSA to explore the potential benefits these new technologies could 

provide to the weapons missions.

Deploying more advanced platforms also 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 is a construction line item that upgraded the LLNL 

computing facility with increased power and cooling capability in preparation for DOE/NNSA’s first 

exascale system, El Capitan, to be deployed in fiscal year (FY) 2023, and subsequent exascale-class 

architectures. Exascale Computing Facility Modernization provides sufficient cooling and power to allow 

initial installation and necessary systems overlap as they are sited and decommissioned. The nuclear 

security enterprise will continue to manage and coordinate code development and facility upgrades with 

system acquisitions to allow HPC platforms use for DOE/NNSA as the technology progresses into the 

exascale era and beyond. 

3.2.2 Simulation Capabilities for Weapon Science, Engineering, and 

Physics

Advanced HPC and simulation codes, models, and data analytics used to simulate and assess the behavior 

of nuclear weapons and their components form another important part of the Weapon Simulation and 

Computing area. Together, these capabilities enable weapon designers to qualify components, certify 

warheads, and assess the stockpile in the absence of underground nuclear explosive tests. These 

capabilities support accelerated nuclear weapons design and production, manufacturing process 

development, and prediction of weapon response to hostile environments, and play a central role in 

assessing the nuclear explosive package’s performance and safety and the reliability of the full warhead 

system in the stockpile-to-target sequence (STS) environments. These codes must also be sufficiently 

flexible and adaptable to run on a variety of the latest HPC platforms.

These capabilities underpin DOE/NNSA’s ability to resolve challenging stockpile problems using codes that 

take advantage of increased spatial and temporal resolution, higher dimensionality, and higher-fidelity 

physical models. Code improvements lead to more predictive simulations that are less reliant on empirical 

calibration to experimental data. These capabilities are essential to addressing issues associated with an 

aging stockpile and modernizing the stockpile with new materials in different configurations without 

resorting to nuclear explosive testing. The nuclear security enterprise also relies on these capabilities to 

continue developing methods for quantifying critical margins and uncertainties (see Chapter 2, 

3 Quantum computing – The area of study focused on developing computer technology based on the principles of quantummechanical theory, which explains the nature and behavior of energy and matter on the atomic and subatomic level.
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Section 2.1.1). These methods are important for understanding discrepancies between physical 

measurements and simulated data.

3.2.2.1 Status

Simulation codes include integrated design codes (IDCs) that perform large-scale, multi-physics 

simulations directly supporting the assessment mission, and weapons science codes that model specific 

phenomena in more detail and inform the models in the IDCs where experiments are lacking. As the 

Nation’s nuclear stockpile evolves to support a responsive and resilient nuclear deterrent, so must the 

simulation capabilities underwriting that stockpile. 

Simulations with improved predictivity that support stockpile certification and modernization also address 

significant finding investigations, and safety scenarios relying on large ensembles of multi-physics, threedimensional calculations with large data movement requirements. Newer generations of IDCs and 

supporting codes are being designed to respond to evolving requirements. Improved physical models are 

needed to address responses to hostile environments and analyses of manufacturing, production, and 

disassembly processes to reduce cost and waste. Future rewrites to accommodate new technologies will 

be expedited through careful modular design and adaptable programming models. 

IDCs and weapons science codes are supported by experimental activities designed through close 

cooperation between the simulation and experimental communities. Simulations, especially those 

resolving three-dimensional features, currently require an extended time to complete on petascale 

machines. As the simulation detail increases into the mesoscale, exascale-class computing will be 

required to resolve these simulations in a responsive timeframe to support experimental needs (see 

Appendix C for detailed information on the Exascale Computing Initiative). In response, DOE/NNSA 

initiated developing a new generation of IDCs, requiring new capabilities in numerical methods, software 

design, and programming models to optimize the use of these emerging HPC technologies. DOE/NNSA 

has also introduced an Advanced Machine Learning Initiative to expand the use of artificial intelligence, 

or Cognitive Simulation capabilities, to better manage the complexity in physics-informed simulations

The DOE/NNSA is also advancing several internal initiatives to leverage developing technologies and 

capabilities to support the nuclear stockpile sustainment. The Large-Scale Calculations Initiative, which is 

currently underway, was initiated to determine the limitations and scaling potential of DOE/NNSA’s

assessment capabilities. The Large-Scale Calculations Initiative is assessing what is achievable with current 

platforms, codes, and qualified personnel and what cannot be achieved with those capabilities. “Largescale calculations,” as defined by this initiative, are impractical to perform on available capacity computing 

platforms due to 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 

mission delivery.

3.2.3 Challenges and Strategies

Table 3–2 provides a high-level summary of the Weapon Simulation and Computing area challenges and 

the strategies to address them.
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Table 3–2. Summary of the Weapon Simulation and Computing area challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

The evolving stockpile necessitates 

new physics, engineering, and 

materials applications that challenge 

the understanding, modeling, and 

simulation capabilities.

Work with 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 efforts to 

improve modeling.

Current strategy is sufficient.

The evolving threat space requires 

new and evolving ways for weapons 

to be certified.

Coordinate with customers through the 

Nuclear Posture Review implementation to 

understand the new needs for threat response 

and to respond with credible simulation 

capabilities.

Current strategy is sufficient.

Improving the rate at which new 

modeling and simulation capabilities 

are provided to the Stockpile Major 

Modernization and Stockpile 

Sustainment programs.

Enhancing the ability to simulate the 

effects of weapons effects, aging, 

and manufacturing changes.

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.

Run IDCs and supporting codes on more 

powerful platforms to allow quicker time-tosolution for applications of simulation 

enhancements.

Current strategy is sufficient.

Performing rapid evaluations of new 

materials and modeling additive 

manufacturing techniques requires 

advanced simulations.

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

Current strategy is sufficient.

Working with IDCs that are not 

effectively using advances that have 

emerged in commercial HPC 

architectures.

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.

Evolve HPC tools for IDCs’ next 

generation to achieve sophisticated 

programming models, software 

designs, and numerical algorithms. 

This development will produce a 

more responsive simulation capability 

that responds more rapidly and 

efficiently to challenges.

Supporting exascale platforms with 

insufficiently structured and sized 

facilities and supporting 

infrastructure (space, power, and 

cooling).

Continue to execute the ASC platform strategy. 

Continually survey HPC vendors’ facility 

requirements, identify gaps, and proceed with 

modernization or new infrastructure solutions 

to meet HPC utility demands.

Current strategy is sufficient.

High demand in multiple industries 

for computational skill sets.

Provide innovative work and continue 

improving career advancement opportunities.

Current strategy is sufficient.

ASC = Advanced Simulation and Computing

HPC = high performance computing

IDC = integrated design code
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3.3 Weapon Design and Integration Area

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 and to validate and verify they will always work as 

expected and never work when not intended. The Weapon Design and Integration area is closely linked 

to the Weapon Science and Engineering and Weapon Modeling and Simulation areas in an iterative 

fashion, such that capabilities in all three areas routinely support efforts in the other two.

3.3.1 Weapon Physics Design and Analysis

Designing and analyzing the nuclear explosive package is required to assess U.S. nuclear weapons, qualify 

and certify changes to the stockpile (such as with life extensions and modernization), evaluate proliferant 

nuclear weapon programs, and respond to emerging threats, unanticipated events, and technological 

innovation. This capability includes potential concept exploration to satisfy requirements and detailed 

development of design, production, certification, and development processes. It also encompasses 

evaluating weapon outputs and effects. 

Weapon Physics Design and Analysis efforts are predicated on codes developed through the Weapon 

Modeling and Simulation area and the nuclear data and material properties that underpin simulation 

tools. Validating and improving these tools also requires data and knowledge acquired through 

hydrodynamic, subcritical, and HED experimental facilities and legacy data from nuclear explosive testing. 

Advances in diagnostics and experimental capabilities are required to obtain suitably high-fidelity data. 

All these related capabilities underpin and are critical for the Weapon Physics Design and Analysis 

capability. 

3.3.1.1 Status

The Weapon Physics Design and Analysis capability provides the foundational tools and methods 

necessary to design and analyze nuclear explosive packages and determine the state of constituent 

materials and components and certify potential future stockpile options with new safety and security 

features. 

Requirements for DOE/NNSA’s current systems will evolve in the future due to component aging or 

remanufacture, the changing threat environment, or the need to transition to alternate materials and 

technologies. In these future scenarios, Weapons Physics Design and Analysis tools will require expanded 

predictive capabilities to assess, and certify, system performance without nuclear explosive testing. In 

addition, the planned warhead modernization requirements over the next decade have expanded. The 

ability to provide timely analysis to support warhead development timelines is critical. 

DOE/NNSA must develop new, highly capable methods for certifying designs that differ from those for 

which DOE/NNSA has a nuclear explosive test history. The national security laboratories are developing 

non-nuclear experimental capabilities and evaluation metrics that can quantify predictions and 

uncertainties for performance and safety without the need for underground nuclear explosive tests. 

3.3.2 Weapon Engineering Design, Analysis, and Integration

The Weapon Engineering Design, Analysis, and Integration capability underpins DOE/NNSA’s ability to 

develop, test, qualify, and certify designs to support a responsive deterrent. This capability employs 

science, technology, and engineering methods so that the integrated solution meets all performance, 

safety, security, and reliability requirements. 
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This capability affects several phases of the weapons life cycle, including concept exploration, design, 

development, and production. It also encompasses systems integration, which includes working with DoD 

to define the functional, physical, performance and interface requirements between the DOE/NNSA and 

DoD systems. DOE/NNSA uses that understanding to develop the subsystem-level requirements among 

the non-nuclear subsystems and the requirements between the non-nuclear components and the nuclear 

explosives package. 

3.3.2.1 Status

While much of the Weapon Engineering Design, Analysis, and 

Integration capability is being exercised by multiple concurrent life 

extension programs (LEPs), Modification Programs (Mods), 

alterations (Alts), and stockpile sustainment, some elements are 

not being adequately exercised. Because modernization activities 

prior to the W87-1 Mod have been focused on extending the life of 

current stockpile weapons, there has been a decline in capacity to 

develop warhead concepts to address military requirements that

differ from those addressed by current stockpile systems. These 

gaps will be closed through activities supporting the Stockpile 

Responsiveness Program by exercising the technical capabilities 

required for all nuclear weapon stages, including design, testing, 

and production, and working in concert with DoD to recruit, train, 

and retain the next generation of weapon designers and engineers.

DOE/NNSA is addressing challenges within digital engineering 

through initiatives to define where specific digital transformation 

opportunities provide value over time and determine where and how changes should be made in policy 

and business processes for the use of digital product definition and associated data. Any transformation 

will require investment decisions in software and information technology (IT) infrastructure. 

3.3.3 Environmental Effects Analysis, Testing, and Engineering Sciences

The Environmental Effects Analysis, Testing, and Engineering Sciences capability uses an array of test 

equipment, modeling tools, and techniques to simulate STS environments and measure the response of 

materials, components, and systems. Examples of environmental testing and modeling conditions 

(normal, hostile, and abnormal) include shock, vibration, radiation, acceleration, temperature, 

electrostatics, and pressure. The engineering sciences that support this analysis include thermal and fluid 

sciences, structural mechanics, dynamics, aerodynamics, hydrodynamics, radiation transport and 

disposition, and electromagnetics. This capability influences the design and qualification of planned and 

future weapon programs, as well as surveillance activities supporting assessment of the safety, security, 

and reliability of the stockpile.

3.3.3.1 Status

As the vision for a future stockpile takes shape, current engineering sciences, experimental capabilities, 

and predictive modeling capabilities may not be sufficient to address future needs confidently and 

comprehensively. DOE/NNSA’s facilities, equipment, and the workforce must be ready and responsive to

upcoming needs. Modeling and simulation capabilities must be able to predict the effects of the STS 

environments. Experimental capabilities are necessary to improve the levels of confidence in all modeling 

and simulation capabilities. DOE/NNSA has been anticipating such changes, and plans are in place to 

address those needs.

Digital Engineering

Digital engineering has empowered a 

paradigm shift from the traditional designbuild-test methodology to a modelanalyze-build methodology. Instead of 

expensive and lengthy design-build-test 

cycles, the goal is to replace the need for 

repeated build-test cycles with simulation 

and analysis in a virtual environment. 

This new methodology requires that 

simulation models to be calibrated and 

qualified in small scale tests beforehand. 

The growing ASC Exascale capability 

combined with artificial intelligence will 

accelerate this digital engineering 

revolution.
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Renewed modernization activities and increasing technical requirements have accelerated the need to 

recapitalize and modernize experimental facilities. Many environmental test facilities are beyond their 

projected design life and need major refurbishment over the next decade, especially considering the 

heavy demand imposed by multiple concurrent weapon programs. The same is true for the programmatic 

equipment supporting the environmental test and engineering sciences facilities. For example, 

DOE/NNSA is currently evaluating options for Combined Radiation Environments for Survivability Testing 

through an Analysis of Alternatives (AoA). This new capability will support DOE/NNSA testing in multiple 

radiation environments using the same experimental platform, either through recapitalizing existing 

facilities or constructing new facilities.

3.3.4 Weapons Surety Design, Testing, Analysis, and Manufacturing

The Weapons Surety Design, Testing, Analysis, and Manufacturing capability includes safety and use 

control system development, analysis, integration, and manufacture to simultaneously minimize the 

probability of unauthorized use and maximize the reliability of authorized use of a U.S. nuclear weapon 

while maintaining the highest levels of safety. All these actions are necessary for a safe and secure 

stockpile. In addition, all aspects of this capability require elevated classification control and secure 

facilities and equipment for surety feature design and manufacturing. National requirements from 

Presidential Directives have been implemented through DOE Orders, and performance-based use control 

requirements introduced by the Deputy Administrator for Defense Programs. These requirements have 

driven a novel approach to surety designs that are more cost-effective with lower manufacturing 

complexity while maintaining the stockpile’s high surety standards.

DOE/NNSA performs assessments that integrate weapon and venue security and control capabilities to 

understand how to best allocate resources to meet evolving threats. This approach includes partnerships 

across DOE/NNSA and the U.S. Government with stockpile and modernization programs, nuclear 

counterterrorism and incident response personnel, and other national assets. The Optical Initiation 

project is one example that incorporates surety technology to meet safety requirements.

3.3.4.1 Status

A variety of surety technologies and approaches have been, or are, currently under development to 

improve the safety and security of nuclear weapons. The program’s focus is on cost reduction of 

components and tailoring the technology options to expectations of future systems. Several core 

technologies have been identified for cost reduction efforts and experiments have proven out the 

complexity reduction. Close collaboration with the production sites has resulted in greater maturity for 

cost estimates. Additionally, several novel approaches for various applications are being evaluated for 

viability and feasibility. The new approaches represent a paradigm shift in how weapons surety is 

evaluated. 

3.3.5 Radiation-Hardened Microelectronics Design and Manufacturing

This capability includes research, design, production, and testing of reliable and robust radiationhardened microelectronics for use in nuclear weapons. The electronics in nuclear warheads must function 

when subjected to a range of radiation sources from within the weapon to cosmic rays and hostile sources 

external to the weapon. 

Radiation-hardened microelectronics perform critical sensing and arming, fuzing, and firing functions so 

weapons work as intended. As operational environments evolve and new requirements emerge, 

DOE/NNSA R&D resources must evaluate and respond to support the safety, security, and effectiveness 

of the Nation’s nuclear deterrent. Production must also keep pace with evolving trends in 
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microelectronics production to maintain a trusted supply of hardened microelectronics for nuclear 

weapon applications. 

DOE/NNSA has developed a Microelectronics Capability Development Roadmap that was informed by 

DOE/NNSA’s continued coordination with DoD. DOE/NNSA is engaged with the Strategic Radiation 

Hardened Electronics Council, the Test and Evaluation, Recruitment and Retention, and Advanced 

Packaging working groups and is the co-lead for the Trust, Assurance, and Nuclear Surety working group. 

3.3.5.1 Status

The Microsystems, Engineering and Sciences Applications (MESA) complex is the enduring lead institution 

for trusted, strategic radiation-hardened microelectronics. DOE/NNSA is committed to sustaining this 

capability through 2040 via implementation of the MESA Extended Life Program, which includes facilities 

and equipment upgrades to maintain and advance capabilities for all active weapons systems, such as the 

W87-1 Mod and W93 development. The limitations of the existing facilities, together with the current 

trends in industry tools and products result in residual risks that cannot be fully mitigated through the 

Extended Life Program. DOE/NNSA is exploring potential solutions to address these risks, working with 

appropriate institutions to conduct materials research, and collaborating with selected manufacturers to 

conduct technology evaluation to address sustaining the capability to 2040 and beyond.

3.3.6 Challenges and Strategies

Table 3–3 provides a high-level summary of the Weapon Design and Integration area challenges and the 

strategies to address them.

Table 3–3. Summary of the Weapon Design and Integration area challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Developing and exercising design 

(rather than assessment) skills in 

physics, engineering, chemistry, and 

materials science personnel.

Implement activities such as

Certification Readiness Exercises, design 

practicums, and other design studies.

Enhance design experience through 

design studies and Stockpile 

Responsiveness exercises, and warhead 

modernization.

Developing and exercising certification 

methodologies using recently

developed physics performance 

metrics on device designs for which 

there is no underground nuclear 

explosive test data.

Develop metrics and apply 

methodologies to implement.

Perform subcritical and HED 

experiments from which metrics can be 

extracted or validated. Develop and 

maintain new and existing facilities and 

capabilities that underwrite qualification 

and certification.

Managing uncertainty related to 

DOE/NNSA’s design capability for reuse 

if new component production is unable 

to meet warhead modernization 

requirements.

Enhancing ability to simulate the 

effects of aging and manufacturing 

changes.

Rely on current simulation capabilities 

(validated by aboveground experiments 

and non-nuclear testing) to model reuse 

design options.

Develop certification methodologies for 

reuse and replacement designs. Close 

the capability gap regarding plutonium 

response evaluation in integrated 

weapons experiments as part of the 

Enhanced Capabilities for Subcritical 

Experiments program.

Applying machine learning to weapon 

physics design problems for current 

system confidence, future system 

certification, and increased 

responsiveness.

Develop capabilities to shorten the 

design loop through workflow 

enhancement and surrogate model

development for faster parameter space 

exploration.

Use machine learning as an accelerant 

capability for data interpretation, 

simulation results implementation, 

certification, design, evaluating 

discrepancies, detecting anomalies, and 

enhancing current solutions.

HED = high energy density
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3.4 Weapon Material Processing and Manufacturing Area

The Weapon Material Processing and Manufacturing Area covers the packaging, processing, handling, and 

manufacturing of plutonium, uranium, tritium, energetic and hazardous materials, lithium, and other 

metal and organic materials needed for nuclear weapons. The current stockpile maintenance and 

modernization programs will continue to demand special nuclear material (SNM), HE, and other energetic 

materials into the distant future. The nuclear security enterprise must maintain reliable production,

science, technology, and engineering capabilities, integrated infrastructure, and logistics (handling, 

storage, delivery, and supply chain management) for raw materials and War Reserve (WR) products. 

Components that contain SNM or energetic materials require a special conduct of operations, physical 

security protection, facilities, and proper equipment to handle, package, process, manufacture, and 

inspect these components. 

SNM-based products must be handled, packaged, processed, manufactured, and inspected and these 

capabilities require many specialized facilities and programs’ support throughout the nuclear security 

enterprise. The obsolescence, age, or severely degraded nature of many of the facilities required to 

produce and process SNM presents operational risks to reliably produce nuclear weapon components. 

The strategies detailed throughout this section for the overall capability are organized by individual 

materials and supporting programs. Any necessary bridging strategy or solution currently being 

implemented as capability investments for each type of component is addressed and major programmatic 

infrastructure projects. 

Concurrent to the development of robust strategies for material supply, several collaborative efforts are 

taking place between production and design agencies to ensure compatibility between design and 

production capabilities, including material quality and throughput. These include production enclaves 

such as the polymer enclave commissioned at LLNL’s site 200 in cooperation with the Kansas City National 

Security Campus (KCNSC), or the proposed energetics enclave at Site 300 in collaboration with Pantex

Plant (Pantex).

3.4.1 Plutonium Management

Maintaining confidence in the nuclear warheads that compose the U.S. nuclear deterrent requires 

DOE/NNSA to reestablish a plutonium pit manufacturing capability. Newly manufactured pits are required 

to enable improved warhead safety and security, mitigate against perceived risk to the nuclear deterrent 

posed by plutonium aging, and support potential changes to future warheads due to threats posed to the 

U.S. nuclear deterrent from renewed peer competition. 

Working closely with DoD, a requirement to manufacture no fewer than 80 WR pits per year (ppy) was 

established. This number is driven by the stockpile’s size, the desire to minimize the number of existing 

pits past the age of approximately 80 years, and the need to have a flexible manufacturing capability with 

the capacity to produce a variety of pits to meet current and planned military stockpile requirements.

DOE/NNSA is implementing a two-site solution with the objective of producing 30 WR ppy at LANL using 

the existing Plutonium Facility (PF-4) and 50 WR ppy at the Savannah River Site (SRS) by repurposing the 

existing facility previously referred to as the Mixed Oxide Fuel Fabrication Facility (MFFF) to meet this 

manufacturing capacity. Both facilities meet the stringent building design standards necessary to support 

pit manufacturing. 

This two-site solution restores a critical production capability central to maintaining the Nation’s nuclear 

deterrent. Operating two geographically separated plutonium pit production facilities provides resilience 
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and adaptable options to mitigate shutdowns, incidents, or other factors that may affect operations at a 

single site. 

Plutonium processing and component manufacturing capabilities are also used for radioisotope 

thermoelectric generator production,

4 pit surveillance, plutonium science and aging studies, subcritical 

experiments, National Aeronautics and Space Administration space exploration, materials recycle and 

recovery, and nonproliferation programs.

3.4.1.1 Status

Based on progress in operations and the maturation of line-item capital asset acquisition projects that 

support the two-site solution for pit production, NNSA’s current assessment of pit production milestone 

status follows:

◼ DOE/NNSA is on a path to make at least 30 ppy at 

LANL and 50 ppy at the Savannah River Plutonium 

Processing Facility (SRPPF). DOE/NNSA continues to 

assess risks to implementing its plutonium pit 

production plan and is implementing mitigation 

options while studying additional trade space to 

recover schedule.

◼ The SRS assessment is based on the ability to meet 

three key requirements to produce WR pits at rate: 

(1) completion of line-item construction and Critical 

Decision (CD)-4, Approve Start of Operations;

(2) demonstrate a WR-quality pit manufacturing 

capability; and (3) demonstrate the ability to 

manufacture at full-rate capacity while maintaining 

WR quality control. The total time duration for 

achieving steps two and three is several years, based on experience. 

◼ Because PF-4 is already conducting plutonium operations at LANL, these three key efforts, to a 

large extent, are being overlapped in time. Since the SRPPF must undergo commissioning to 

startup plutonium operations, the three key pit requirements to achieve 50 WR ppy will occur 

sequentially.

In addition to dedicated infrastructure efforts at LANL and SRS, DOE/NNSA is recapitalizing other existing 

facilities through a series of reinvestment projects, including several line-item projects, to replace the 

current aging capability to provide supporting functions and processing infrastructure for pit production 

qualification processes, risk-reduction, and increased reliability activities. The Chemistry and Metallurgy 

Research Replacement project maintains continuity in analytical chemistry and material characterization 

capabilities by transitioning these activities from the nearly 70-year-old Chemistry and Metallurgy 

Research Facility to newer facilities. The Material Recycle and Recovery program is conducting risk 

reduction activities by removing the nuclear material inventory currently housed in the Chemistry and 

Metallurgy Research Facility. 

4 Radioisotope thermoelectric generators – A type of lightweight, reliable nuclear battery with no moving parts that uses an array 

of thermocouples to convert the heat released by the decay of plutonium-238 into electricity.

A vacuum induction furnace safely melts, and casts, 

plutonium metal, a part of the pit production process 

at Los Alamos National Laboratory.
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3.4.1.1.1 Approach at Los Alamos National Laboratory for 30 War Reserve Pits Per Year

DOE/NNSA will establish a reliable capability at LANL to deliver 30 WR ppy. There are several key steps to 

delivering 30 WR ppy:

◼ Advance the science and mature the engineering to meet the LLNL design agency specifications 

in support of delivering a first production unit.

◼ Maintain and update PF-4 to ensure reliability and continued compliance with all relevant safety 

requirements.

◼ Reconfigure PF-4 for efficient pit production by completing the ongoing equipment installations 

and facility modification to optimize the pit production process flow and establish the capacity for 

a reliable 30 WR ppy production rate.

◼ Increase the workforce required for the pit production mission to manufacture pits; maintain and 

operate facilities; provide security for pit production activities and materials; and provide a broad 

range of support functions.

◼ Provide acceptable components and support for the experiments and evaluations specified by the 

LLNL in the Pit Certification Plan Under the guidance of the Pit Production Realization Team.

Plutonium metal purification, casting, machining, and assembly are all currently performed at LANL’s PF-4, 

while the Radiological Laboratory/Utility/Office Building houses plutonium chemistry operations that 

support plutonium component production, surveillance, and science missions. DOE/NNSA will transition 

PF-4 to be available 24/7 for scheduling programmatic work, facility maintenance, equipment installation, 

and construction activities to accommodate increased operations. DOE/NNSA also will use a waste 

management program at LANL to maintain efficient and continuous off-site shipments to the Waste 

Isolation Pilot Plant.

3.4.1.1.2 Savannah River Site Approach to Producing a Minimum of 50 War Reserve Pits Per 

Year

DOE/NNSA will reach 50 WR ppy production as close to 2030 as possible by repurposing the former MFFF 

as SRPPF. 

SRPPF will be 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. 

Initial modernization activities include repurposing and transitioning the MFFF into a safe, secure, 

compliant, and efficient pit production facility, the planned SRPPF. Developing new facilities and security 

infrastructure and establishing a new program office at SRS to sustain an enduring pit production goal of 

50 plutonium ppy are also underway. Preliminary and final design efforts for the SRPPF project are in 

progress with knowledge gained from LANL, LLNL, and other sites. 

There are several key steps to completing the SRPPF project and establishing an enduring production 

mission: 

◼ Complete five interrelated construction subprojects.

◼ Hire and train the workforce necessary to establish and sustain the SRS pit production mission.

◼ Begin production operations upon CD-4 to enable delivery of a first production unit pit.
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◼ Establish the institutional systems at SRS necessary to build WR pits.

◼ Establish and manage SRS pit production interfaces across the nuclear security enterprise.

◼ Re-establish a secure supply chain to support the SRS pit production mission.

Further design activities conducted supporting CD-2, Approve Performance Baseline, will identify multiple 

opportunities to accelerate achieving the required production capacity. One opportunity already 

down-selected is the use of a High Fidelity Training and Operations Center, which will reduce the time 

required from CD-4 to delivery of first production unit pit by facilitating operator training and qualification 

and supporting certification activities in cold environments. Establishing required SRPPF pit production 

capacity as close as possible to 2030 remains a high priority and is required for sustaining the Nation’s 

nuclear deterrent’s effectiveness.

The proposed pit production mission will need a skilled workforce at the site. Estimates indicate design 

and construction activities will require approximately 3,000 staff. Sustained production of 50 WR ppy at 

SRS will require nearly 2,000 production and support staff. These estimates will continue to be refined as 

the project’s design matures. LANL is actively supporting a knowledge transfer program for the SRS pit 

production mission with subject matter expertise. 

DOE/NNSA will undertake a multi-year training and qualification process to ensure the necessary people, 

processes, procedures, and commodities are in place to meet the minimum 50 ppy requirement at SRS. 

Essential to this process will be transitioning an existing facility into the SRS High Fidelity Training and 

Operations Center expected to be completed prior to the SRPPF main process building. The Center will 

enable unclassified and classified training in a non-nuclear environment, aimed to qualify the personnel 

and procedures ultimately used to build and handle pits in the SRPPF main process building. The Center

will also advance final design by serving as a proving ground for selected engineering equipment and a 

test bed 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. This knowledge transfer program will form the foundation of the 

High Fidelity Training and Operations Center knowledge and experience base.

3.4.1.1.3 Status of Other Plutonium Activities

Many other production, surveillance, and research activities involving plutonium must be conducted 

throughout the nuclear security enterprise, including radioisotope thermoelectric generator production 

and surveillance, subcritical plutonium experiments, pit certification, environmental testing, and material 

processing. Conducting these activities requires close coordination between the sites to execute the 

disassembly activities, evaluations, experiments, analysis, and recovery. 

A responsive plutonium infrastructure requires proper storage facilities, safe and secure disposal 

pathways, and unique equipment and facilities for R&D activities.

3.4.1.2 Challenges and Strategies

Table 3–4 provides a high-level summary of plutonium handling, packaging, and processing challenges 

and the strategies to address them.
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Table 3–4. Summary of plutonium handling, packaging, and processing challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Timely integration of infrastructure 

and workforce investments in 

alignment with W87-1 program 

needs to reestablish required pit 

production capabilities and capacity.

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 MFFF 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.

Reestablish the 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 thermal and mechanical 

testing capabilities to evaluate newly 

manufactured and legacy pits in the STS 

sequence normal environments.

Establish equipment, experimental 

platforms, and systems to evaluate 

additional normal and abnormal 

environments that pits could experience.

Leverage the ongoing investment in the 

Enhanced Capabilities for Subcritical 

Experiments Program to demonstrate 

the certification uncertainty achieved 

with one-point and multi-point safety.

CD = Critical Decision

MFFF = Mixed Oxide Fuel Fabrication Facility

ppy = pits per year

SMEs = subject matter experts

SRPPF = Savannah River Plutonium Processing Facility

STS = stockpile-to-target sequence

WR = War Reserve

3.4.2 Uranium Management

Uranium is a strategic national defense asset with different assays and enrichments, including highly 

enriched uranium (HEU), low-enriched uranium (LEU), and depleted uranium (DU). Uranium has a variety 

of defense and other applications, including weapon components and fuel for naval reactors, commercial 

power reactors (for tritium production), and commercial and research reactors (medical isotope 

production).

3.4.2.1 Highly Enriched Uranium

HEU is needed to support stockpile programs, Naval Reactors, and Nonproliferation programs. Uranium 

Modernization supports these efforts through modernizing the infrastructure around HEU processing, 

purification, machining, and other operations. Particularly, the program is working to phase out mission 

dependency on Building 9212 at the Y-12 National Security Complex (Y-12). The program is working 

toward completing the following actions to ensure the success of this transition:

◼ Relocating HEU capabilities from Building 9212 into the Uranium Processing Facility and other 

enduring facilities.
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◼ Leveraging these relocations to develop and deploy new technologies that will improve safety, 

reduce costs, and enhance throughput to meet future needs.

◼ Investing in key systems such as casting, machining, metal purification systems, assembly, and 

analytical chemistry capabilities to ensure long-term reliability.

3.4.2.2 Status

DOE/NNSA manages and operates the Nation’s primary uranium processing and storage capabilities at 

Y-12, and several laboratories for R&D capabilities at Y-12 and other locations across the nuclear security 

enterprise. Building 9212 at Y-12 houses the most hazardous of the HEU processing capabilities; however,

at more than 75 years old, the facility is deteriorating and does not meet modern nuclear safety and 

security standards. DOE/NNSA is decreasing mission dependency on this facility by relocating certain 

uranium purification and processing capabilities to existing facilities at Y-12, and through construction of 

the Uranium Processing Facility. In addition to relocating these capabilities, DOE/NNSA is modernizing 

them to increase safety and efficiency, ensuring future material needs can be met. 

The Uranium Processing Facility will replace Building 9212 capabilities for HEU casting, special oxide 

production, chemical recovery, decontamination, and assay. 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. 

While the Uranium Processing Facility is constructed and undergoes startup activities, DOE/NNSA will

relocate capabilities for HEU purification and chip processing, deploying new technologies that will fully 

enable phasing out mission dependency on Building 9212 and meet future mission needs. Ongoing 

projects include electrorefining, calciner, and direct chip melt (recovery of enriched uranium machine tool 

chips and turnings by collecting and melting them in a furnace), which will reduce cost and improve 

manufacturing processes for nuclear weapon materials. These capabilities will replace the hazardous HEU 

processing capabilities, improve safety, and reduce risk. Technology maturation, such as for 

electrorefining and direct electrolytic reduction, is funded and monitored by the Uranium Modernization 

Program. When the technology is sufficiently mature, the equipment development and deployment is 

pursued through capital line-item acquisition and major item of equipment processes, as appropriate. 

This process has generated three current major items of equipment acquisitions to enable the following 

processes:

◼ Electrorefining is the electrochemical purification process for HEU metal. This capability, located 

in Building 9215, along with the calciner process in Building 9212 (see below), will replace the 

current high-hazard wet chemistry process located in Building 9212.

◼ The calciner process uses 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, 

ensuring all material is recovered, aiding in shutdown activities. This process, along with the 

electrorefining capability in Building 9215 (see above), will enable the shutdown of the current 

high-hazard wet chemistry process in Building 9212.

◼ Direct Chip Melt is the process by which HEU machine tool chips/turnings are recovered and 

melted in furnaces. This capability, located in Building 9215, will replace the current high-hazard 

practices where chips are transferred to Building 9212, then cleaned, briquetted, and stored 

there.
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DOE/NNSA will perform its enriched uranium metal purification in Building 9215 using the electrorefining 

process, which will achieve CD-4 in 2023. Uranium Modernization will continue to fund the hazardous 

wet chemistry metal purification process in Building 9212 until the electrorefining process is fully 

operational, at which point wet chemistry in Building 9212 will be shut down. 

Uranium Modernization currently uses Y-12’s Building 9212 resources to supply the stockpile with purified 

HEU metal. The program provides a comprehensive storage capability to support a steady material supply 

stream 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 inventory

composition. The program, partnering with DOE/NNSA’s Office of Infrastructure, is sustaining existing 

and enduring uranium facilities with an Extended Life Program. These efforts allow safe and secure 

operations to continue, including those relocated from Building 9212, in existing facilities through 2040 

and beyond. 

Uranium Modernization is proactively removing equipment that is no longer needed from these enduring 

facilities through its Flexible Production Capacity Initiative to improve Y-12’s responsiveness and 

resiliency. 

3.4.2.3 Challenges and Strategies

Table 3–5 provides a high-level summary of highly enriched uranium handling, packaging, and processing

challenges and the strategies to address them.

Table 3–5. Summary of highly enriched uranium handling, packaging, and processing

challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Bringing new processes online and 

shutting down hazardous processes.

Verify equipment meets all requirements 

and use Operational Release Plans to 

streamline the transition to operations.

Support past project closure, ensuring

the transition to production is 

successful.

Developing processes to bridge 

capability gaps as Building 9212 is 

phased out.

Closely monitor and work with the site to 

advance technology development and plan 

how to move projects forward.

Closely monitor project schedules and 

prepare fallback options to ensure 

mission demand is met.

Preparing Building 9212 for 

disposition and demolition.

Shutdown high-hazard processes as new 

processes are brought online and begin 

material removal, maintaining a 15+ year 

schedule.

Current strategy is sufficient.

Continuing operations in aging 

facilities with increasing safety, 

security, and environmental 

requirements and maintaining them 

until operations transition to newly 

deployed facilities.

Make short- to medium-term 

recapitalization investments where 

reasonable. Find adaptive solutions to 

maintain facilities past their useful lives.

Execute future projects including 

electrical, utility upgrades, and other 

identified structural life-extending 

efforts, as identified in the 

implementation plan.

Growing and maintaining SMEs across 

the nuclear enterprise.

Increase hiring to plan for multi-year 

training and clearance requirements.

Transfer knowledge from SMEs near 

retirement age to new SMEs.

Collaborate with national laboratories and 

industry to develop next generation of 

subject matter expertise.

Gather and collate knowledge from 

SMEs through documentation programs 

targeting critical knowledge areas.

SME = subject matter expert
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3.4.2.3.1 Depleted Uranium Modernization

DU, a HEU enrichment process byproduct, has a lower concentration of the fissile isotope uranium-235 

and a higher concentration of the fissionable isotope uranium-238 than natural uranium. DOE/NNSA must 

have the capability to produce certified components made from high purity depleted uranium metal 

(HPDU) and DU-niobium alloy (binary) to fulfill mission requirements.

DU and binary are required for nuclear component production to maintain and modernize the stockpile 

through LEPs, Mods, and limited life component (LLC) exchange programs. DU and binary are processed 

into precision components through complex processes that must meet stringent requirements. Key 

processes include alloying, casting, rolling, swaging, forming, forging, machining, assembly, welding, and 

inspection.

3.4.2.3.2 Status

The Depleted Uranium Modernization Program was established in FY 2021 by consolidating the DU

portions of the previous Uranium Sustainment Program and other related programs. DU capabilities 

include feedstock procurement, restarting and maintaining legacy Vacuum Induction Melt-Vacuum Arc 

Remelt alloying and manufacturing processes, and investing in new key technologies. In the early 2000s, 

these capabilities lapsed due to materials reuse, low-demand signals, and prioritizing other activities. The 

Depleted Uranium Modernization Program is restarting these capabilities to meet imminent mission 

requirements. 

DOE/NNSA has a long-term requirement to reestablish a reliable supply of HPDU before the current 

inventory is exhausted. DOE/NNSA is working toward an AoA study to determine the best approach to 

meet the mission need for HPDU supply. One concept is to develop a uranium hexafluoride (DUF6) to 

uranium tetrafluoride (DUF4) conversion line and establish a capability to convert DUF4 to HPDU metal. 

DOE/NNSA is also evaluating if recycling DoD DU munitions to mitigate schedule risks associated with 

establishing a DUF4 conversion line is feasible or not. 

Figure 3–3. High Purity Depleted Uranium supply chain

DOE/NNSA is developing new technologies to replace and augment aging capabilities and to provide a 

more efficient and cost-effective means of producing binary components, allowing DOE/NNSA to meet 

future production demands while reducing feedstock demand. For example, Direct Casting is a technology 

being developed to supplement current wrought activities that would significantly reduce equipment 

failure risk, decrease material waste, and improve process efficiency. The Depleted Uranium 

Modernization Program is also pursuing new technologies for material reuse and recycling, such as 

electron beam cold hearth melting of binary. These new technologies have the potential to significantly 

reduce risks to production and DU and binary components material feedstock in the future stockpile.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-32

Figure 3–4. Depleted Uranium Modernization Process flow chart

DOE/NNSA’s Manhattan Project-era facilities continue to experience age-related failures that present 

significant risk to mission delivery and personnel safety. Short-term stockpile demands require dedicated 

resources to restart and modernize legacy-DU processing capabilities. Ultimately, to meet long-term 

stockpile demands, DOE/NNSA will invest in a new dedicated DU facility. 

3.4.2.3.3 Challenges and Strategies

Table 3–6 provides a high-level summary of depleted uranium modernization challenges and the 

strategies to address them. 

Table 3–6. Summary of depleted uranium modernization challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

HPDU inventory insufficient to meet 

long-term demands.

Purchase existing, limited HPDU supplies 

from commercial vendors.

Scaling up DU munitions recycling to 

convert to HPDU.

Conduct AoA study to inform alternatives 

for creating DUF4 feedstock.

Invest in EBCHM and direct casting to 

reduce overall HPDU demand.

DU alloying capabilities have lapsed 

and need to be restarted and 

modernized to support future 

stockpile needs.

Invest in the restart and maintenance of 

the legacy alloying processes. 

Purchase additional equipment to reduce 

the strain on legacy equipment and 

processes. 

Coordinate across production and design 

agencies to expedite binary qualification. 

Use the NNSA Binary Working Group to 

manage existing and future binary 

supplies and set NNSA priorities.

Deploy EBCHM 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 | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-33

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.

Identify bottlenecks and develop bridging 

strategies to fulfill near-term mission 

requirements should new technology not 

be employed in the immediate future. 

Purchase wrought critical spare parts to 

sustain the process.

Invest in direct casting technology to 

produce component technologies more 

efficiently and reliably.

Current DU facilities experience agerelated failures and have insufficient 

floor space to support future 

stockpile demand.

Identify opportunities to meet capacity 

within existing space using process 

improvements, upgraded equipment, and 

future needs and capacity modeling. 

Invest to recapitalize the aging physical 

infrastructure, thus reducing risk to 

produce strategic materials and 

components.

Establish a combination of on-site and offsite storage capabilities to store required 

HPDU feedstock quantities to meet future 

mission demand.

Evaluate long-term DU facility options to 

meet future stockpile demands.

Sustain existing DU facilities with a 

DU/binary strategy to ensure safe and 

secure operations in existing facilities 

through 2040 or until a replacement 

facility is constructed. 

Continuing operations in aging 

facilities with increasing safety, 

security, and environmental 

requirements and maintaining them 

until operations transition to newly 

deployed facilities.

Make short-term to medium-term 

recapitalization investments where 

reasonable. Find adaptive solutions to 

maintain facilities past their useful lives.

Execute future projects including 

electrical, utility upgrades, and other 

identified structural life-extending 

efforts, as identified in the 

implementation plan.

Growing and maintaining SMEs 

across the nuclear enterprise.

Increase hiring to plan for multi-year 

training and clearance requirements.

Transfer knowledge from SMEs near 

retirement age to new SMEs.

Collaborate with National Labs and 

industry to develop next generation of 

subject matter expertise.

Gather and collate knowledge from 

SMEs through documentation programs 

targeting critical knowledge areas.

AoA = Analysis of Alternatives

DU = depleted uranium

DUF4 = uranium tetrafluoride

EBCHM = electron beam cold hearth melting

HPDU = high purity depleted uranium

SME = subject matter expert

3.4.2.4 Domestic Uranium Enrichment 

Enriched uranium contains higher concentrations of the fissile uranium-235 isotope than natural uranium. 

DOE/NNSA requires enriched uranium at varied enrichment levels for tritium production, 

nonproliferation, and the Naval Reactors Program. The Domestic Uranium Enrichment Program is 

responsible for ensuring a reliable supply of enriched uranium is available to support U.S. national security 

needs. Since the 2013 closure of the Paducah Gaseous Diffusion Plant, near Paducah, Kentucky, the 

United States has lacked the capability to produce enriched uranium free of peaceful use obligations (i.e., 

unobligated). While commercial LEU sources exist, they carry peaceful use obligations and are therefore 

unusable for defense missions. Mission needs for enriched uranium are currently fulfilled via the United 

States’ existing HEU inventory (including downblending HEU to produce LEU where needed), which is a 

finite and currently irreplaceable source.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-34

3.4.2.4.1 Status

The Domestic Uranium Enrichment Program is implementing a three-pronged strategy to supply current 

enriched uranium needs and reestablish a domestic uranium enrichment capability for long-term enriched 

uranium needs:

◼ Downblend HEU to LEU to extend the tritium fuel need date to 2044. DOE/NNSA has identified 

existing unobligated and unencumbered material to power the Tennessee Valley Authority (TVA)

reactors through 2044. Much of the material is HEU “scrap,” which is unattractive for use by other 

programs. This effort maintains continuous vendor downblending operations, 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 

Laboratory to ensure a centrifuge technology is available in time to be deployed in a domestic 

uranium enrichment capability.

◼ Execute the acquisition process to deploy an enrichment technology. Because the HEU 

inventory has a finite nature, the United States will eventually need a new uranium enrichment 

capability. DOE/NNSA approved CD-0 for this capability in December 2016 and expects to make 

a final technology down-select and deployment decision in the mid-2020s.

3.4.2.4.2 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.

DOE/NNSA has invested in two centrifuge 

technologies to provide optionality and 

contingency.

DOE/NNSA continuously assesses its 

inventory to identify unobligated enriched 

uranium that may provide additional 

development time or margin to the LEU 

need date.

Continue developing centrifuge 

technologies to reduce long-term 

deployment risks.

Sources of unobligated LEU are finite 

and limited.

DOE/NNSA continuously assesses its 

inventory to identify any additional 

unobligated enriched uranium.

Establish a reliable source of 

unobligated enriched uranium.

LEU = low-enriched uranium
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-35

3.4.3 Lithium Management

3.4.3.1 Lithium

Lithium handling, packaging, and processing is a capability that is key to the 

nuclear weapon production mission. It continues to have increased focus due 

to supply, production, and infrastructure issues. DOE/NNSA requires 

specialized, weapon-specific forms of lithium for stockpile sustainment and is 

the sole source provider for these materials. DOE/NNSA manufactures lithium 

materials into precise nuclear weapon components that meet stringent 

specifications to support warhead modernization programs and joint test 

assembly requirements, and to support tritium-producing burnable absorber 

rod (TPBAR) production for the tritium production, handling, and processing 

program. 

3.4.3.2 Status

Lithium for the weapons program is currently provided via a 

recycling process that relies on dismantled weapon feedstock 

to supply material for processing. Nondestructive and 

destructive testing is performed for lithium components in 

full assembly and part forms as part of surveillance data 

collection for ensuring confidence in the stockpile. Additional 

material is provided to the Department of Homeland Security 

and DOE Office of Science for various needs, and to other 

customers through the Strategic Partnership Program 

process. 

DOE/NNSA is actively pursuing alternate, advanced lithium 

purification techniques. Technology Readiness Assessments 

are conducted as needed to assess the strengths and weaknesses of identified technologies. 

Currently, aging infrastructure and antiquated equipment present risks to mission delivery that, if realized,

will affect the ability to meet stockpile requirements. The 79-year-old facility where lithium is processed 

has structural issues due to chemical degradation, which poses safety and environmental concerns, and a 

replacement facility is needed. DOE/NNSA continues to execute and revise a lithium strategy to maintain 

sufficient lithium processing capabilities (from raw materials to finished assemblies) to meet near-term

and long-term requirements. The strategy includes the design and construction of a new Lithium 

Processing Facility by 2031 to house modernized lithium processing capabilities. The Lithium Processing 

Facility F has received CD-1, Approve Alternative Selection and Cost Range, approval and is on track for 

CD-2/3 approval first quarter of FY 2026.

DOE/NNSA will continue to work with stakeholders 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. Subject matter expert (SME) growth and sustainment will require SMEs 

undergo continued training and development to produce lithium components and resolve technical issues 

associated with these complex production processes. 

3.4.3.3 Challenges and Strategies

Table 3–8 provides a high-level summary of lithium handling, packaging, and processing challenges and 

the strategies to address them.

Lithium metal from technology 

maturation efforts

Restored electrolytic cell at Y-12

Lithium metal from technology 

maturation efforts
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-36

Table 3–8. Summary of lithium handling, packaging, and processing challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Meeting manufacturing 

deliverables using existing aging 

and degraded facilities.

Sustain current operations in the legacy 

lithium facility to meet near-term 

stockpile needs.

Reestablish a small-scale purification 

capability and restart some legacy 

processing capabilities to supplement 

recycling activities.

Plan and prioritize recapitalization 

projects and risk reduction activities to 

keep facilities and process equipment 

functional until the Lithium Processing 

Facility is qualified.

Design and construct the Lithium 

Processing Facility. Continue to maintain 

legacy processing efforts through the 

identified facility life cycle extension 

project until the Lithium Processing Facility 

is fully qualified.

Sustaining the supply of recycled 

lithium during potential shortages.

Restart a small-scale purification 

capability and legacy processing 

capabilities in the legacy lithium facility 

to provide additional feedstock material.

Deploy/recapitalize new equipment 

(production cleaning station glovebox, 

backup pressure vessel, backup 

crusher/grinder) to increase capacity and 

provide redundancy to reduce likelihood 

of single-point failures.

Monitor and optimize weapons 

dismantlement schedule to provide 

feedstock as needed.

Develop and prioritize new process 

technologies and equipment to maximize 

efficiency and reliability in meeting 

stockpile needs.

Complete the qualification for the 

production parts cleaning station glovebox.

Identify, plan, and schedule future weapon 

system qualifications for direct material 

manufacturing feed material.

Complete the qualification for the 

refurbished purification and legacy 

processing capabilities. 

Develop, update, and sustain program 

management tools to optimize the 

feedstock production schedule.

Sustaining lithium production with 

current inefficient processes.

Develop and mature lithium process 

technologies to introduce efficiencies 

into the current process and prepare for 

insertion in process facilities.

Further develop small-scale wet chemistry 

to purify legacy material not suitable for 

the direct materials manufacturing 

process.

Mature process improvements for legacy 

processes (e.g., next-generation 

electrolytic cell and improved purification).

Continuing operations in aging 

facilities with increasing safety, 

security, and environmental 

requirements and maintaining 

them until operations transition to 

newly deployed facilities.

Make short-term to medium-term 

recapitalization investments where 

reasonable.

Find adaptive solutions to maintain 

facilities past their useful lives.

Execute future projects including electrical, 

utility upgrades, and other identified 

structural life-extending efforts, as 

identified in the lithium implementation 

plans.

Optimize the purification processes design

for the Lithium Processing Facility.

Grow and maintain SMEs across 

the nuclear enterprise.

Increase hiring to plan for multi-year 

training and clearance requirements. 

Transfer knowledge from SMEs near 

retirement age to new SMEs.

Collaborate with national laboratories 

and industry to develop next generation 

of SMEs.

Gather and collate knowledge from SMEs 

through documentation programs 

targeting critical knowledge areas.

SMEs = subject matter experts
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-37

3.4.4 Tritium Management

Tritium, a strategic material used for national security purposes, is placed in gas transfer system (GTS) 

reservoirs, and used to meet weapon system military specifications, increase system margins, and support 

weapon system reliability. Due to the rate of radioactive decay, tritium must be replenished periodically 

in these components. DOE/NNSA produces tritium for this purpose and others using TPBARs that are 

irradiated in the Watts Bar Unit 1 and Watts Bar Unit 2 nuclear reactors (WBN 1 and WBN 2) operated by 

TVA. Because this is defense-purposed tritium, WBN 1 and WBN 2 require unencumbered and 

unobligated LEU use as fuel (i.e., LEU that is free of any peaceful use restrictions). Once the TPBARs are 

irradiated, the bars are transported to SRS, where the tritium is extracted, stored, and loaded into GTS 

reservoirs. In addition to tritium production at TVA, tritium supplies from previously filled reservoirs are 

recycled to maintain required inventories. Most of DOE/NNSA’s tritium capability activities focus on 

stockpile requirements, but activities also include tritium gas processing R&D, GTS life storage, helium-3 

recovery, and stockpile surveillance. 

3.4.4.1 Status

DOE/NNSA has a multi-year plan of producing and recycling 

tritium to meet national security requirements and 

demonstrating a highly reliable supply chain. DOE/NNSA 

continues to deliver the requisite supply by using TVA’s WBN 1 

and WBN 2 reactors. The goal to reach maximum tritium 

production in each of the two Watts Bar reactors by FY 2025 is on 

schedule. Extraction of tritium from irradiated TPBARs at SRS is 

ongoing in accordance with the multi-year plan. 

DOE/NNSA manages numerous facilities at SRS that support 

tritium handling, processing, and storage functions, including 

recovery, nondestructive analysis, and surveillance, and is 

implementing a plan to replace, or recapitalize, aging facilities. 

This plan focuses on facilities maintenance and the need for 

supply chain management (e.g., vendors, tritium R&D 

capabilities, etc.). 

The Tritium Finishing Facility line-item project, along with several 

minor construction projects and equipment 

replacement/upgrade projects, will replace the critical 

capabilities occurring at the existing 60-year-old manufacturing 

building that operates 24/7 for GTS production and surveillance. 

Examples of these required smaller projects include:

◼ Replacing large, obsolete distributed control systems for the gas processing equipment

◼ Replacing and electronic refurbishing mass spectrometers to analyze gas associated with 

processing equipment

◼ Installing a hydrogen/tritium separation capability in the Tritium Extraction Facility

◼ Replacing the deuterium/tritium separation equipment, including support systems and valves

◼ Several minor construction projects to address end of life, safety, and space requirements

The SRS Tritium Extraction Facility performs 

a cask receipt, enabling TPBARs to be 

moved safely from shipping casks to basket.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-38

Some of the scope described above will require significant processing downtime, particularly replacing

the deuterium/tritium separation equipment. Maintaining the equipment replacement sequence and 

timing will be critical to minimize downtime. 

3.4.4.2 Challenges and Strategies

Table 3–9 provides a high-level summary of the tritium production, handling, and processing challenges 

and the strategies to address them. 

Table 3–9. Summary of the tritium production, handling, and processing challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Maintaining a reliable tritium supply 

chain to meet tritium inventory and 

availability requirements to load 

GTSs on schedule.

Assess supply chain risks and 

opportunities. Investments are being 

made that will provide high-level 

reliability, flexibility, and resiliency to the 

program.

Continue to monitor risks and 

opportunities to identify cost-effective 

solutions and retain high reliability.

Planning for alternative tritium 

production technologies or methods 

due to the uncertainties associated 

with Nuclear Regulatory Commission

approval of operating license 

renewal applications in 2055 for 

Watts Bar Units 1 and 2. 

Invest in studies that identify and monitor 

viable and emerging replacement 

methods and technologies as risk 

mitigation for long-term tritium 

production.

Monitor evolving technologies and 

invest in existing or new technologies as 

appropriate. 

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 on schedule to replace 

infrastructure critical to stockpile 

deliverables at SRS by 2031. Continue 

long-lead procurements and other 

activities needed to support replacement 

of aged tritium isotopic equipment and 

support systems in CY 2025.

Monitor emerging needs and implement 

strategies and actions to mitigate risks.

Developing technologies that further 

enhance stockpile maintenance and 

evaluation and increase efficiency of 

processes throughout the tritium 

production life cycle. 

Invest in fundamental tritium science,

including 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.

Planning for long lead times to hire, 

clear, and train personnel.

Examine multiyear staffing needs 

appropriate to ensure a continuous 

knowledge, skills, and abilities influx to 

sustain capabilities. 

Implement additional strategies to 

maximize knowledge retention and 

minimize workforce turnover. 

Alt = alteration

CY = calendar year

GTS = gas transfer system

LEP = life extension program

Mod = modification

TPBAR = tritium-producing burnable absorber rod

3.4.5 High Explosives and Energetics Management

Energetics development and production, including the associated manufacturing processes and 

infrastructure, are required to meet legacy material demands and to modernize stockpile applications. 

Energetics are materials that provide instantaneous energy through an exothermic chemical reaction. 

Energetics include specific end products, such as HE that include conventional HE and insensitive HE, low 

explosives (e.g., pyrotechnics and propellants), their respective energetic ingredients, and various inert 

ingredients required for manufacturing (e.g., polymers, reactants, catalysts, plasticizers, oxidizers, fuels, 
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-39

ballistic modifiers, stabilizers, surfactants, and bonding agents). Across the enterprise, DOE/NNSA 

laboratories and production sites handle energetic material as part of the nuclear weapon sustainment 

and warhead modernization missions. 

The current stockpile maintenance and modernization programs will continue to demand energetic and 

hazardous materials. Ensuring DOE/NNSA has the capability to properly handle, package, process, and 

manufacture energetic and hazardous materials is essential to supporting the nuclear deterrent.

This capability depends on the ability to perform HE and energetic scientific and engineering activities, 

and is united with the ability to handle, package, and process SNM (plutonium and uranium) (Section 3.4.1 

and 3.4.2). 

The nuclear security enterprise must maintain reliable production; science, technology, and engineering 

capabilities; an integrated infrastructure; a robust domestic supplier base; and logistics (handling, storage, 

and delivery) for raw materials and WR products. Most 

of the current facilities were built over 70 years ago, 

lack the electrical infrastructure to meet mission 

requirements, and have safety and security limitations 

because infrastructure is failing. New facilities 

construction and existing energetic facilities

recapitalization across the nuclear security enterprise 

are needed to improve the capability and capacity 

required by increased modernization efforts, 

continuing challenges associated with a limited vendor 

base, and advancements to energetic manufacturing.

HE processing, production, and manufacturing are 

currently performed externally by a vendor and 

internally at the Pantex. This capability encompasses 

the ability to supply raw material, procure HE from the vendor, and perform safe HE processing into 

precision parts meeting tight specifications. The current stockpile planned warhead modernization 

programs, LLC exchanges, and future modernization programs will continue to demand HE and energetic 

materials. 

In each weapon, DOE/NNSA uses either one of the two types of HE produced in the main charge of a 

nuclear weapon: (1) insensitive HE, which provides greater safety and security of the stockpile by reducing 

the risk of low‐likelihood but high‐consequence accidents from initial build through retirement and 

disassembly, and/or (2) conventional HE, which provides enhanced performance for a lower volume and 

weight. The type of HE used changes depending on the weapon type and purpose. 

3.4.5.1 Status

The facilities and equipment that support this capability pose mission risks due to their aging and declining 

condition and must be maintained through rigorous corrective maintenance, preventive maintenance, 

and calibrations. 

Experienced and knowledgeable personnel are needed to properly care and handle energetic and 

hazardous materials. Also, recruitment of skilled professionals and extensive safety training are 

imperative for safe operations. With an increased workload and the attrition/retirement of senior 

personnel, DOE/NNSA must focus on building and training a workforce that can safely perform these 

operations well into the future.

DOE/NNSA completed the Nuclear Explosive Package 

Engineering Test’s functional test phase in 

January 2022.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-40

DOE/NNSA is currently planning three major programmatic line-item construction projects for HE. The 

High Explosives Science and Engineering Facility will consolidate 15 aging facilities into 3 new and more 

efficient facilities to conduct science, technology, engineering, and production activities in weapons 

assembly/disassembly and HE. The High Explosives Science and Engineering Facility received CD-2/3 

approval in the third quarter of FY 2022 and commenced construction immediately. CD-4 is planned for 

FY 2027. The HE Synthesis, Formulation, and Production project will address challenges at the supplier’s 

production facility and address the difficulties in meeting DOE/NNSA production requirements. It plans 

to receive CD-3A approval for the first quarter of FY 2024 and CD-4 approval fourth quarter of FY 2030. 

Areas that will be addressed include explosive and mock formulation operations to support multiple 

weapon programs, technology development for future programs, and support for strategic partners. 

Finally, the Energetic Materials Characterization project will provide the capability to perform energetics 

material characterization, analysis, and testing, and will replace obsolete facilities that pose risks to 

workforce safety.

Future infrastructure enhancements may include consolidating and modernizing existing facilities critical 

to meet the stockpile’s HE production capabilities for energetic components (main charges, boosters, 

actuators, igniters, rocket motors, timers, and detonators) in a modern and enhanced safety and security 

environment. DOE/NNSA also will continue to implement minor construction to mitigate known issues 

with the limited commercial component vendor base to provide on-site production of energetic 

components in the stockpile (actuators, igniters, detonators, timers, rocket motors). 

3.4.5.2 Challenges and Strategies

Table 3–10 provides a high-level summary of the high explosives and energetics management challenges 

and the strategies to address them.

Table 3–10. Summary of the high explosives and energetics management challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Nuclear security enterprise infrastructure 

for energetics face aging critical facilities 

and equipment (many past their life 

expectancies), increasing demands for 

capability and capacity, and uncertainty 

in material production due to a singlesource vender base.

Coordinate with the Infrastructure and 

Operations Program 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 

equipment refinancing planning across 

the nuclear security enterprise. 

Find creative solutions to maintain 

facilities past their useful life.

Make short-term to medium-term 

refinancing investments where 

reasonable.

Engage and enable sites to reduce 

dependency or better enable external 

suppliers.

Construct the HE Synthesis, 

Formulation, and Production building, 

the HESE Facility, and the Energetic 

Materials Characterization facility.

Identify and invest in equipment 

requirements through input from the 

sites and link them to defined risks and 

capability gaps.

Employ creative methods to mitigate 

obsolescence issues, such as using 

additive manufacturing to produce 

parts.

Stand up production enclaves at design 

laboratories to enable more efficient 

response to the emerging deterrent.

Prototyping Capabilities, funded at the 

production agencies, would better 

serve this need by not only addressing 

emerging needs, but by also providing 

early visibility and involvement that 

would accelerate transitions from 

development into production. See 

Section 3.5.23.5.4. 
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-41

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Dependence on a small and shrinking 

vendor base to supply the explosives, 

constituent components, and specialized 

equipment needed to produce its 

energetic end products.

Establish clear requirements for 

Nuclear Enterprise Assurance. 

When necessary, use in-house 

capabilities to restore mission 

schedules at risk.

Respond to situations by acting to 

stabilize suppliers or fund management 

and operating partner activities to 

qualify new ones. Support cooperative 

arrangements with DoD and 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, capacity, resources, and 

equipment to supply HE for WR 

energetics.

Developing sufficient supply chain 

capacity for energetic materials in 

current and future LEPs and Alts.

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 design for 

manufacturing, and requirements and 

capacity integration.

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 outof-spec material to meet requirements.

Planning for 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 form 

energetic materials.

Complete triaminotrinitrobenzene/

PBX-9502 specifications will improve 

plans and processes to enhance 

inventory control. 

Preserve and enhance in-house 

production for items such as WR 

detonator powder production.

Alt = alteration

HE = high explosives

HESE = high explosives science and engineering

LEP = life extension program

WR = War Reserve
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3.4.6 Additional Material Needs

Specialized components and materials that are not commercially available must be produced within the 

nuclear security enterprise. This production may require organic materials and processing production, 

manufacturing, and metallic and organic products inspection, based on knowledge of material behavior, 

compatibility, and aging. This would include, but is not limited to, polymer material and part 

manufacturing.

3.5 Weapon Component Production Area

The Weapon Component Production area includes multiple capabilities for producing all the non-nuclear 

components and the arming, fuzing, and firing system, and for designing, developing, engineering, and 

integrating other materials, from components to prototype high-quality and full-scale nuclear explosive 

packages and/or their major assemblies. This area also includes the advanced manufacturing capabilities 

that apply modern technologies to advance NNSA legacy and existing processes for making and producing 

weapons components and systems. The capability area involves internal and external manufacturing and 

maintenance and of a broad supply base for parts. It also includes identifying and verifying trusted 

suppliers to provide materials and parts within the weapon product realization process.

3.5.1 Non-Nuclear Component Modernization and Production

The Non-Nuclear Capability Modernization Program manages projects and executes strategies to 

modernize, monitor, and ensure DOE/NNSA’s non-nuclear capabilities and capacities. The Non-Nuclear 

Capability Modernization Program provides funding to modernize and strengthen capabilities required for 

full product realization, including design development, qualification, and production of non-nuclear 

components for multiple weapon systems. Non-nuclear components and subsystems make up more than 

half the cost of each warhead modernization activity. This program consolidates management and 

oversight of strategic investments in technology, equipment, infrastructure, tools, and materials.

Non-Nuclear Capability Modernization activities include:

▪ Procuring equipment

▪ Meeting non-nuclear component design, qualification, and manufacturing capacity 

requirements

▪ Increasing non-nuclear component manufacturing in capacity and capability within the nuclear 

security enterprise and extending and strengthening the trusted supplier base

▪ Sustaining DOE/NNSA’s capability to produce trusted microelectronics

▪ Re-establishing critical capabilities for the design, production, and qualification of nuclear 

weapon electrical and mechanical systems

▪ Modernizing capabilities with a fragile vendor base such as Power Sources program deliverables

▪ Reducing component manufacturing costs through introducing modernized processes and 

technologies

▪ Developing a pre-qualified and trusted commercial partsinventory to avoid delays in integrating 

commercial off-the-shelf components into DOE/NNSA systems
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Production sites work with the national security laboratories early in the design phase to provide 

production perspectives on material selections and designs to enhance components producibility. The 

national security laboratories define the component testing requirements for acceptance through a 

variety of specialized procedures to ensure materials meet design specifications, parts are manufactured 

within acceptable tolerances, and assemblies function as intended. 

3.5.1.1 Status

DOE/NNSA has made progress in developing rapid prototyping and advanced manufacturing capabilities 

that have the potential to accelerate production, reduce production issues, and deliver better overall 

products at lower costs. 

Production sites are facing capacity shortfalls in production and components development due to 

increased weapon modernization requirements and scope. The increased workload has resulted in a 

growth in the KCNSC management and operating partner’s workforce that has more than doubled since 

2014. DOE/NNSA is adding additional production capacity through leasing at KCNSC and shifting 

production to other DOE/NNSA sites while simultaneously increasing the supplier base for commercial 

component production. Off-site office space has been leased to meet the increased office employment. 

KCNSC is leasing an additional 275,000 square feet of space for manufacturing to meet the near-term 

weapon modernization mission. Additional space will be needed for long-term manufacturing 

requirements. LLNL and KCNSC jointly developed and implemented the Polymer Enclave to help ensure 

production capacity for the W80-4 and W87-1. Further, the Enclave has enabled advanced Direct Ink 

Write (DIW) technology research and production process development to better integrate and increase 

cycles of learning for the technology, resulting in more rapid product development for the programs.

All modernization programs and future planned nuclear weapon systems require power sources, and 

DOE/NNSA has concluded there is an unacceptable risk to power source development and production due 

to failing and inadequate power source facilities and an unreliable supplier base. DOE/NNSA is investing 

in the development of new power source technologies across the nuclear security enterprise to expand 

the option space for safe and reliable long-term power sources that can meet evolving system 

architectures. Currently, the mission assignment for design and production agencies for power source is 

assigned to SNL. DOE/NNSA completed an AoA Study in 2020 and identified a preferred alternative for 

pursuing capital acquisition of a line-item construction project to address this risk. Current stockpile 

stewardship plans are forecasting sustained high workload for power sources production over the next 

decade. 

Similar issues hold true for radiation-hardened microelectronics at SNL’s MESA complex; the MESA 

facilities and existing equipment face obsolescence and are becoming less suitable for mission use. MESA 

has an ongoing extended life program to sustain MESA’s capabilities through 2040. In addition, plans are 

being developed for sourcing and manufacturing these microelectronics well past 2040. 

Aging equipment poses reliability and obsolescence issues, resulting in greater operations continuity risks. 

The Capabilities Based Investments program helps mitigate these risks and related ones through projects 

which refinance high risk failure test, measurement, and production equipment. In addition, DOE/NNSA 

is pursuing efforts to better understand current and future equipment needs across the nuclear security 

enterprise for all aspects of the nuclear weapons mission, including non-nuclear production, through the 

Programmatic Recapitalization Working Group. This working group is a combination of participants from 

the Office of Defense Programs and the Office of Infrastructure, and has full participation from each of 

the DOE/NNSA sites. The concern with aging capabilities extends to major environmental test facilities 

used to qualify and assess non-nuclear components in their extreme environments to high reliabilities not 

required for commercial products. The majority of these facilities, including the Annular Core Research 
Department of Energy/National Nuclear Security Administration | April 2023

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Reactor, are decades old and, similar to production facilities, have suffered from technology obsolescence 

and deferred maintenance over the years. These facilities must remain operational to assure qualifying

non-nuclear components does not become critical path for the modernization programs. 

DOE/NNSA is becoming increasingly dependent on internal production due to difficulty finding trusted 

sources for non-nuclear weapon components such as power sources, cables, and radiation-hardened 

microsystems. This insourcing may require additional facilities, equipment, and infrastructure for certain 

product lines. In the long term, capital reinvestment will be crucial to maintaining DOE/NNSA’s 

manufacturing and testing capabilities suite. Developing additional qualified commercial suppliers will 

help this effort, although commercial demand for these products, with less stringent production 

requirements, is posing challenges throughout the supplier base. 

3.5.1.2 Challenges and Strategies

Table 3–11 provides a high-level summary of non-nuclear capability modernization challenges and the 

strategies to address them. 

Table 3–11. 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.

DOE/NNSA will develop options for 

additional space or more efficient use 

of existing space. Planning is 

underway to determine the most 

prudent solutions to provide 

increased production capacity at SNL 

(for Power Sources) and KCNSC.

Additionally, production enclaves 

enable increased production at 

production sites.

The MESA complex at SNL fulfills an 

enduring need for radiation-hardened 

microelectronics. A Federal Management 

Plan will implement processes to validate 

sustainment and modernization needs, 

identify potential funding gaps, and 

develop mitigation strategies to ensure 

MESA capabilities continue to meet 

stockpile sustainment and modernization 

needs through 2040.

Integration of New Technologies: As new 

manufacturing techniques are developed, 

qualified, and accepted, new production 

capabilities are required to support 

manufacturing involving different 

materials, multi-function machines, 

additive manufacturing, and other new 

approaches. Space for the new 

capabilities is required in addition to 

current equipment until legacy 

technologies can be retired.

The Capability-Based Investments 

program is providing interim relief for 

some of the critical equipment needs 

related to these key product lines. 

Investments in multiple Advanced 

Manufacturing technologies are being 

made across several NNSA sites and 

are expected to be used by FY 2023. 

Additionally, production enclaves at 

design laboratories enable new 

manufacturing techniques to 

transition smoothly to production by 

encouraging early DA-PA interactions.

The Non-Nuclear Capabilities Program will 

continue to collaborate with the Research, 

Development, Test, and Evaluation 

Program Office to identify promising 

technologies that could/would be 

committed to future modernization 

programs if sufficiently mature and fund 

them to higher technology readiness levels 

and manufacturing readiness levels.

5

 

These technologies) will enable 

improvements in stockpile safety, security, 

use control, and reliability, while 

minimizing the schedule, performance, 

and cost risk to the identified 

modernization program.

5

Technology readiness level (TRL) is a measurement system to assess the maturity level of a particular technology that includes 

nine levels, where TRL 1 is the lowest (the associated scientific research is beginning) and TRL 9 is the highest (a technology has 

been proven through successful operation). Manufacturing readiness level (MRL) is a means of communicating the degree to 

which a component or subsystem is read 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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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Material Availability: Some material 

supplies are limited to only those 

quantities remaining from legacy 

programs yet continue to be in demand 

by weapons programs. Vendors have lost 

the capability, capacity, or interest to 

produce more of these materials.

Current efforts for managing these 

critical materials consist of 

establishing a central database for atrisk materials and providing a 

transparent supply chain network and 

associated risks by industry experts. 

Supply chain analysis and studies will 

examine supplier network risks for nonnuclear components and provide 

recommended policy actions, production 

activity practices, and material solutions to 

improve supply chain resiliency. These 

efforts also coordinate across DOE/NNSA 

to prioritize supplier risks, develop 

enterprise-wide mitigation strategies, and 

leverage available policy tools such as the 

Defense Production Act, and leverage 

existing partnerships such as with DoD.

Vendor Implications: Risks in the 

available supplier base and the need to 

produce more classified components is 

driving a need for additional in-house 

production capability while continuing to 

identify and qualify additional suppliers.

The program will support non-nuclear 

component material development 

and replacement identified for use. 

The program will then engage in 

activities to modernize DOE/NNSA’s 

industrial capacity for its 

implementation.

Early engagement with design 

requirements to research potential new 

qualified sources. Baseline capabilities at 

the design agencies to quickly fulfill 

unexpected needs.

DA-PA = design agency-production agency

MESA = Microsystems Engineering, Science and Applications

3.5.2 Weapon Component and Material Process Development

The Weapon Component and Material Process Development 

capability is focused on research, development, engineering, and 

integrating technologies into production operations to improve 

cycle time, cost, safety, security, reliability, and performance. 

This capability entails improving required manufacturing, 

scientific, and engineering capabilities in the production 

environment, while also meeting DOE/NNSA production 

requirements. 

Weapon Component and Material Process Development 

capabilities must include the ability to rapidly develop and 

mature manufacturing processes and technologies. Advanced 

manufacturing technologies and digital-based processes are 

needed to reduce cost and support mission success. Historically, 

these processes and technologies have been matured late in the 

process, with limited time to produce viable component and 

material options to support production. The expanding scope of 

the weapon modernization programs is driving increased 

complexity and diversity of production demands, which 

inherently slows process and technology maturating. 

The Weapon Component and Material Process Development 

capability develops innovative manufacturing processes, technologies, and materials that are necessary 

to address obsolescence due to sunset availability, regulatory safety, or security requirements, and to 

reduce schedule and cost risks.

Weapon Component and Material 

Process Development Accomplishments

In the absence of a suitable commercial 

solution, a custom software package for DIW 

was developed and deployed. LayerUp 

uniquely combines capabilities to generate 

complex toolpaths for 5-axis printing, 

corrects for substrate surface variations and 

handles high precision multi-material 

dispensing and flow control. LayerUp also 

provides a user-friendly interface and quality 

control capability to support rigorous nuclear 

security enterprise qualification needs. 

Compared to the previous scripting R&D 

solution, LayerUp reduces the toolpath 

computation time from 3 hours to 7 minutes. 

Notably, LayerUp has been selected as the 

baseline software for W80-4 LEP polymer 

DIW components and is being adopted by 

the W87-1 program for both polymer and 

thermoset DIW components.
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3.5.2.1 Status

DOE/NNSA must achieve higher technology and manufacturing readiness levels and buy down risks, 

enabling faster insertion of new technologies into weapon systems for the modernization programs to 

succeed in reducing costs and increasing agility. Programs associated with the Weapon Component and 

Material Process Development capability continue to develop and improve multi-system component and 

manufacturing processes, reducing costs, and improving schedule execution for the nuclear security 

enterprise. 

Current processes and infrastructure are inadequate to meet 

goals for rapid design, production, testing, and qualification of 

equipment and technologies to meet modernization needs. 

These inadequacies are hampering focus on development 

efforts separate from production demand, which has reduced 

the ability to innovate new solutions that could help assure 

responsiveness to future needs. 

Advances in the Weapon Component and Material Process 

Development capability are currently constrained by aging 

infrastructure and associated reliability risks. Aging 

manufacturing equipment is leading to increased downtime 

and reduced product yield. At the same time, sustaining or 

restarting legacy processes is affected by equipment and 

material obsolescence. DOE/NNSA must also address facility 

capacity issues due to the increased production demand from 

multiple concurrent modernization programs. DOE/NNSA is performing AoA studies to seek ways to 

mitigate any potential adverse effects to existing and future programs caused by insufficient facility 

capacity and emerging production needs.

3.5.3 Weapon Component and System Prototyping

The Weapon Component and System Prototyping capability supports efforts to develop, test, analyze, and 

manufacture high-fidelity, full-scale prototype weapon components and systems to reduce the cost and 

cycle times required to develop modern designs and technologies prior to production. This capability 

includes the ability to design, manufacture, and employ mock-ups with sensors to support laboratory and 

flight tests that will provide component functionality evidence with DoD delivery systems in realistic 

environments. Identifying, developing, and sustaining process expertise and prototyping is crucial to 

scientific understanding, production agility, responsiveness, and efficiency in the ever-changing threat 

environment. 

The Weapon Component and System Prototyping capability supports DOE/NNSA to replace sunset 

technologies and obsolete materials and use technological advances from industry and academia. This 

approach provides weapon designers the opportunities to take prudent risks before use in stockpile 

warheads, facilitates rapid/accelerated learning cycles, and integrates multidisciplinary, multi-site teams 

to support laboratory and flight tests to provide evidence that components will function in relevant 

environments. 

Weapon Component and System Prototyping facilitates an effective nuclear deterrent through proactive 

design and innovative weapon technologies development. Such activities may include:

◼ Developing technology insertion options to prepare the nuclear stockpile for changing global 

security environments, such as advanced hardware design for nuclear explosive packages, 

Weapon Component and Material Process 

Development Accomplishments

The capability to print high performance 

thermoset epoxy composites using existing 

DIW tools has been established. The 

Additive Manufacturing Thermosets team has 

rapidly on-boarded the technology and 

printed different prototype iterations for 

analysis and consideration for use on the 

W87-1. These materials and processes 

provide additive manufacturing technologies 

that are readily adaptable to design changes 

and potentially more manufacturable than 

conventional technologies.
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energetics, microelectronics/microprocessors, mechanisms, GTSs, initiation systems, and neutron 

generators.

◼ Partnering with DoD’s Science and Technology community to mature and demonstrate integrated 

system architectures to accelerate innovation and reduce risks in the nuclear weapons 

development life cycle.

3.5.3.1 Status

Aging facilities and legacy processes are not easily, or economically, modifiable to new technologies. 

DOE/NNSA requires capabilities to provide rapid development cycles through modular systems, rapid 

prototyping, integrated simulation, and realistic combined environments testing to develop components 

and systems. The ability to realize designs quickly and receive rapid feedback will promote innovation as 

risks and barriers to participation are lowered. 

Advancements in science and technology improve warhead performance and manufacturing. Recently, 

innovatively applying additive manufacturing and model-based systems engineering have created new 

approaches for weapon technology prototyping. These new technologies will provide options to solve 

warhead issues that can be implemented more quickly, cost less, and/or provide greater performance 

than is possible with existing technologies and processes.

3.5.4 Advanced Manufacturing

The Advanced Manufacturing capability advances novel manufacturing processes to enable a 

responsive and resilient nuclear security enterprise. These innovations simultaneously open component 

design space while reducing component R&D costs. In addition, benefits from advanced manufacturing 

capabilities include a reduced manufacturing footprint, waste, and facility operating costs and increased 

production throughput and improved manufacturing safety basis.

This capability underpins innovation in future nuclear weapons systems and allows the enterprise to 

quickly respond to emerging issues in the current stockpile and respond to future weapons requirements 

resulting from an evolving geopolitical landscape. Many advanced manufacturing capabilities are 

available for the future production capabilities, including additive manufacturing for metals and polymers, 

injection molding, standing up internal materials production capabilities and new materials with better 

properties, and manufacturing simulation capabilities. 

3.5.4.1 Status

All new advanced manufacturing technologies require stringent R&D to ensure the components produced 

by these new methods can meet or exceed the requirements of legacy components. This requirement 

allows the enterprise to field new concepts for the entire life cycle of a weapons system without needing 

underground nuclear explosive testing. DOE/NNSA created a long-term Advanced Manufacturing 

Strategic Program Plan linked to the Nuclear Weapons Council strategic guidance, and the Technology 

Development Strategic Plan to implement this requirement. 

The plan covers objectives including continuous improvement on processes, securing materials and 

component supply chains, adopting modern, risk-based manufacturing qualification methods, developing 

efficient and cost-effective manufacturing technologies, reducing time to deploy advanced manufacturing 

technologies, and discovering the “art of the possible.” Efforts across these themes will directly affect the 

agility and responsiveness of DOE/NNSA’s manufacturing infrastructure and will continue to develop the 

required manufacturing capabilities prior to a future weapon program’s development engineering phase, 

producing confidence in the schedules and cost estimates for those programs.
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Emerging advanced technology solutions will enable a flexible, digital-based enterprise that will use a 

common set of trusted models and simulations throughout the entire product life cycle. Benefits include 

reduced and errors; ability to simulate and predict outcomes for critical manufacturing processes, thereby 

reducing the iterations needed for manufacturing development, rapidly incorporating requirements 

modifications, and enhanced producibility, agility, and responsiveness.

The DOE/NNSA sites are working collectively to rapidly advance additive manufacturing, an emerging

technology, for nuclear deterrence applications. DOE/NNSA established a multi-site Additive 

Manufacturing Coordinating Team to coordinate activities across the enterprise. There are many benefits 

the enterprise is realizing from additive manufacturing including customized tooling and fixturing, weapon 

component weight reduction, and rapid prototyping. 

Technology maturation for advanced manufacturing must be aligned with current and future warhead 

modernization schedules to become responsive to future challenges and execute the current program of 

record.

3.5.5 Challenges and Strategies

Table 3–12 provides a high-level summary of the Weapon Component Production area challenges and the 

strategies to address them. 

Table 3–12. Summary of the Weapon Component Production area challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Cross-program Integration: Extensive 

interactions are necessary across 

program elements, to ensure the full 

suite of advanced manufacturing 

capabilities are matured in time for 

future programs of record. These 

maturation activities are multidisciplinary and often very broad in 

scope because engineering and material 

science functions are required 

throughout the life cycle of a weapon 

system. 

Program managers meet regularly to 

identify opportunities and effect 

coordination. Additionally, regular 

meetings with Management and 

Operating managers help to inform and 

discuss emerging issues and maturation 

progress. 

Earlier and more frequent 

communication across federal program 

managers and Management and 

Operating managers to ensure early 

collaboration and consensus on 

necessary activities. 

Identification of Risks: Lack of highfidelity risk assessment contributes to 

missing insertion opportunities for 

advanced technology and engineering 

into the stockpile or adding new or 

enhanced manufacturing capabilities for 

production. Risks identified later in a 

technology or manufacturing process 

maturation leads to additional 

unforeseen R&D scope that needs 

additional resources and time to buy 

down. The resultant schedule slip 

increases the likelihood the technology 

will not be ready in time for insertion to 

the stockpile.

Maturation of advanced manufacturing 

capabilities is strengthened by using

product business cases and partnerships 

across programs to understand the risk

extent for inserting the new capability 

into the stockpile.

Ensure early stakeholder engagement 

in the technology development cycle to 

best understand the full range of risks 

to inserting a new technology. 

Capturing these risks in a business case 

and using the R&D phase of a 

technology to buy down these risks and 

discover additional risks with more 

than enough time to explore solutions 

before stockpile insertion. 

R&D = research and development
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3.6 Weapon Assembly, Storage, Testing, and Disposition Area

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 a yearly basis 

for surveillance to provide data to evaluate the stockpile’s health. 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. Nuclear weapons undergo disposition at 

their end of life, or due to other reasons. This area covers all these capabilities. 

3.6.1 Weapon Assembly, Storage, and Disposition

The Weapon Assembly, Storage, and Disposition capability involves assembly, disassembly, and inspection 

of nuclear weapons systems, including lower-level subassembly of components and final assembly of the 

nuclear and non-nuclear components. All these activities require special conduct operations, equipment, 

facilities, and quality control, and special safety and security processes and protocols. 

3.6.1.1 Status

DOE/NNSA maintains extensive infrastructure to assemble, disassemble, store, and dispose of weapons 

at a central site, and R&D capabilities throughout the enterprise. Storage, disassembly, and assembly of 

components occurs at the production facilities, depending on the mission. Much of this specialized 

infrastructure is aging, with some facilities exceeding 50 years of age. Capital investments are essential 

to the overall strategy for modernization of this capability. 

Programmatic equipment that supports this capability is also degrading due to age and condition, and 

some pieces are becoming obsolete due to unavailable parts and emerging new technology. Sophisticated 

measurement devices, vacuum chambers, gloveboxes, ovens of many types, lathes of varying sizes, 

environmental chambers and rooms, and various types of nondestructive testing such as radiography, 

laser gas sampling, and computed tomography that all contribute to the viability of this capability and 

depend on this specialized equipment remaining robust. Some new equipment has been installed, but 

many additional equipment replacements are needed to meet mission requirements. As part of the 

overall strategy, DOE/NNSA is investing in upgrading obsolete items of equipment and the facilities in 

which the equipment is used. 

3.6.2 Weapon Component and System Surveillance and Assessment

This capability evaluates weapons and components across weapons-relevant environments to 

demonstrate that stockpile systems continue to meet design and performance requirements. Such 

evaluations occur through inspections, laboratory and flight tests, destructive and nondestructive tests, 

and component and material appraisals. Comparing surveillance results over time provides the ability to 

detect, assess, and resolve aging trends and abnormal changes in the stockpile, potentially predict 

phenomena before the stockpile is affected, and address or mitigate issues or concerns. 

3.6.2.1 Status

The Weapon Component and System Surveillance and Assessment capability is essential to surveillance 

and assessment activities and depends on a broad array of specialized equipment. DOE/NNSA possesses 

a flexible and dynamic evaluation plan that responds to emerging issues and new information, thus 

enabling adjustments as conditions change and key priorities remain met. This planning includes 

identifying issues with the aforementioned equipment and mitigating them accordingly.
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3.6.3 Testing Equipment Design and Fabrication

The Testing Equipment Design and Fabrication capability includes special test equipment design, 

fabrication, and deployment to simulate environmental and functional conditions and collect 

performance and diagnostic data to evaluate against requirements. Data from test equipment provide 

evidence for process qualification, weapon certification, reliability, surety, product acceptance, and 

stockpile evaluation and are used to evaluate performance at all assembly levels.

3.6.3.1 Status

Due to the age of current testers and associated equipment, it is becoming increasingly difficult to obtain 

replacement parts, acquire software upgrades, and maintain test equipment for production and 

surveillance. As a result, operational quantities of some test equipment are diminishing. Furthermore, 

data quantity and complexity requiring collection and processing has challenged the sites’ ability to 

handle, analyze, store, and transfer data. Efforts continue to enhance the common tester architecture, 

improve trusted, robust test solutions, and develop the next-generation foundation bus that will improve 

connectivity, interchangeability, and multi-use compatibility with components and systems in the future. 

A surveillance tester sustainment effort has been initiated and surveillance testers (and potential risk) are 

regularly assessed through stockpile evaluation program planning.

3.6.4 Challenges and Strategies 

Table 3–13 provides a high-level summary of Weapon Assembly, Storage, Testing, and Disposition area

challenges and the strategies to address them.

Table 3–13. Summary of Weapon Assembly, Storage, Testing, and Disposition area challenges 

and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

It is difficult to obtain replacement 

equipment and infrastructure provisions

(facilities, infrastructure, and utilities) to 

adequately perform weapon assembly 

storage and disposition.

Identify aging facilities and infrastructure in 

advance and corresponding plans and 

campaigns for upgrades and replacements.

Current strategy is sufficient.

It is difficult to obtain replacement 

equipment, testers, software, and related 

infrastructure provisions necessary to 

adequately perform testing and 

component and system surveillance.

Identify aging equipment and sunset 

technologies in advance and mitigation 

strategies to compensate for gaps and 

diminishing quantities of hardware.

Current strategy is sufficient.

Numerous capabilities and resources 

have strained or insufficient capacity to 

meet sustainment and modernization 

demands.

Cross-complex working groups prioritize

activities to minimize impacts.

Current strategy is sufficient.

Aging testers supporting surveillance are 

becoming unreliable and unsupportable 

due to sunset technologies.

Sites partner with Headquarters to migrate 

surveillance test capability from old and 

unsupportable testers to modern, common 

platform testers to support components 

that are common across multiple programs. 

This migration not only makes the common 

platform tester sustainable for the future 

and reduces. Required floorspace for 

surveillance testing.

Tester refresh/migration to a 

common platform for 

components that will be surveilled 

as those components approach 

last production unit.
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3.7 Transportation and Security Area

The Transportation and Security area involves DOE/NNSA’s capabilities for protecting the people, places, 

information, and other aspects critical to the nuclear security enterprise’s function. The Secure 

Transportation capability provides safe, secure transport of the Nation’s nuclear weapons, weapon 

components, and SNM throughout the nuclear security enterprise to support DOE/NNSA operations. The 

Safeguards and Security capability protects all nuclear materials, infrastructure assets, information, and 

the workforce at DOE/NNSA sites involved in Weapons Activities programs and operations. The IT and 

Cybersecurity capability supports secure electronic connectivity across the enterprise and guards against 

threats to data integrity.

3.7.1 Secure Transportation

Nuclear weapon warhead modernization, LLC exchanges, surveillance, dismantlement, nonproliferation 

activities, and experimental programs rely on transporting weapons, weapon components, and SNM on 

schedule and in a safe and secure manner. The Secure Transportation capability supports DOE/NNSA’s 

goals, including to consolidating nuclear material storage and reducing the dangers and environmental 

risks posed by domestically transporting nuclear cargo. This capability includes design and fabrication or

vehicle modification, leading edge communication systems, and Federal Agents training. 

Weapons Activities missions receive the highest priority, but the Secure Transportation capability also 

provides secure transport for other DOE/NNSA programs and offices, such as the DOE/NNSA Nuclear 

Counterterrorism and Incident Response Program, the DOE/NNSA Office of Naval Reactors, and DOE 

Office of Nuclear Energy, as well as DoD and other U.S. Government agencies. The capability also supports 

nuclear materials recovery from partner nations. 

The Secure Transportation Asset (STA) Program, which provides this capability, has a record of 100 percent 

safe and secure shipments without compromise, loss of components, or release of radioactive material. 

STA is U.S. Government owned and operated due to the control and coordination required and the 

potential security consequences of material loss or compromise. 

3.7.1.1 Status

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 Federal Agent workforce.

The process of identifying, designing, procuring, and manufacturing vehicles takes several years. The 

Safeguards Transporter (SGT) fleet vehicles reached the end of the projected design life cycle in 2018. STA 

is sustaining this capability by implementing risk-reduction initiatives to extend the life of the SGT until 

the replacement, known as the Mobile Guardian Transporter (MGT), is fully integrated into mission 

operations. The MGT will assure weapon-related cargo and containers’ safety and security, protect the 

public, and meet nuclear explosive safety standards. 

A business case analysis to review options for replacing STA aircraft fleet was performed in FY 2018. The 

analysis supported a McDonnell Douglas DC-9 replacement and a long-range replacement plan for the 

current fleet of two Boeing 737 aircraft. STA procured a 737 (replacement for the DC-9) in FY 2021 and is 

planning for the first 737 life cycle replacement in 2027 and the second in 2032.

As with other capabilities, STA is committed to a robust human resources strategy that recruits and retains 

people with the requisite skills to meet priorities and mission requirements. This strategy considers the 

many years it takes to achieve growth in the Federal Agent workforce due to the stringent hiring process, 
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-52

security clearances, and attrition. During the Coronavirus Disease 2019 (COVID-19) pandemic, STA’s 

mission has not ceased—STA’s ability to effectively meet customer requirements proved STA to be highly 

dynamic and adaptable to the ever-changing environment.

3.7.1.2 Challenges and Strategies

Table 3–14 provides a high-level summary of Secure Transportation Asset challenges and the strategies 

to address them.

Table 3–14. 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.

Continue to evaluate, update, and 

replace STA assets as required to 

meet mission. Incorporate MGT 

into mission operations as fleet 

becomes available (beginning in 

FY 2027).

MGT = Mobile Guardian Transporter

SGT = Safeguards Transporter

STA = Secure Transportation Asset

3.7.2 Safeguards and Security

The Safeguards and Security (S&S) capability protects NNSA personnel, facilities, nuclear weapons, and 

SNM from a full spectrum of specified threats at its national laboratories, production plants, processing 

facilities, and security sites. This capability protects the enterprise from theft, diversion, sabotage, 

espionage, unauthorized access, compromise, and other hostile or noncompliant acts that adversely 

affect national security. The S&S program achieves this capability by ensuring integration amongst several 

components including protective forces, physical security systems, information security, personnel 

security, material control and accountability, and security program operations and planning. 

3.7.2.1 Status

DOE/NNSA must maintain the safety and security of the nuclear security enterprise and its workforce 

despite changing mission needs and ever-evolving threats. The following outlines the status of each S&S 

component and how it supports the entire NNSA mission. 

DOE/NNSA is projecting an unprecedented increase in protective force personnel through FY 2027 in 

support of known mission growth across the nuclear security enterprise, including the pit production 

mission. DOE/NNSA’s standardization initiative for life cycle replacement of its aged rifles will achieve 100 

percent completion during FY 2022.

DOE/NNSA continues to employ proprietary state-of-the-art physical security systems to protect key sites. 

A modernized security system is currently under development, with testing projected to occur in FY 2022 

and 2023. Planned counter unmanned aircraft systems projects are at various stages of installation, and 

testing efforts continue at several sites. For specific system and site information refer to the classified 

Annex.

DOE/NNSA eliminated the personnel security clearance inventory backlog and continues to upgrade the 

web-based Clearance Action Tracking System, develop policy, and update training that supports federally 

mandated Trusted Workforce requirements.
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DOE/NNSA, in partnership with the National Training Center, initiated the contractor Material Control and 

Accountability Technical Qualification Program Pilot. More than 135 individuals have received training 

during eight separate sessions. The Material Control and Accountability Technical Qualification Program 

is critical to addressing significant attrition and turnover of material control and accountability personnel 

across the enterprise, and the program will continue into FY 2023.

DOE/NNSA supports mission growth by prioritizing programs and projects based on prudent risk 

management and acceptance. DOE/NNSA continues to implement the Design Basis Threat (DBT) policy,

specifically, the DBT’s Change 1 requires a security posture assessment against new threats, followed by 

the appropriate adjustments. DOE/NNSA continues to refine and implement a comprehensive risk 

management framework to inform nuclear security decisions. 

Growth within Weapons Activities programs requires increases to the S&S capabilities including additional 

personnel in the various security disciplines along with corresponding investments to maintain and 

modernize security infrastructure and technologies. 

3.7.2.2 Challenges and Strategies

Table 3–15 provides a high-level summary of Safeguards and Security challenges and the strategies to 

address them.

Table 3–15. Summary of Safeguards and Security challenges and strategies

Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Rapidly evolving threats • Complete CUAS deployment at remaining 

planned sites 

• Engage other government agencies on the 

UAS threat and furthering CUAS technologies

• Analyze UAS threat as part of the DBTa

process

• Continue to collaborate with other 

government agencies to address the 

ever-evolving UAS threat

• Analyze and incorporate of future 

CUAS technologies 

Modernize security systems and 

leverage new technology 

• Develop a modernized security system for 

future deployment

• Collaborate through CSTARTbto identify 

advancements in technologies, to include 

artificial intelligence, and integrate into 

future system designs and installations

Assess and deploy future technologies 

through formal efforts (e.g., testing and 

evaluation, etc.) with multiple 

collaborators

Aging security infrastructure Prioritizing security infrastructure 

recapitalization efforts through the Security 

Infrastructure Revitalization Program and West 

End Protected Area Reduction project at Y-12.

Use the Physical Security Technology 

Management Plan to update the current 

plan

DVE threat Partner and liaise with FBI Joint Terrorist Task 

Forces and the Department of Homeland 

Security to provide information regarding DVE 

activity in the vicinity of NNSA equities 

Develop dedicated DVE analysis function 

with advanced tools for threat and 

social media analysis capability 

Enhance cybersecurity protection 

solutions for security systems

In partnership with DOE/NNSA OCIO, develop 

and deploy security systems and technologies to 

defend against cyber threats and resilient to 

intrusions 

Ensure all systems are modernized to 

mitigate cyber vulnerabilities

eConversion of Personnel 

Security Files to electronic 

media

Contract awarded to vendor to complete 

scanning and validation of files, monitoring and 

tracking tasks, productivity, and trends

Realign eConversion of Personnel 

Security Files project focus on Human 

Reliability Program actions 
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies Needed

Implementation of Trusted 

Workforce

Develop policy and implementation plans for 

investigation and adjudication 

Adjust to real-time vetting and 

adjudication model

CUAS = counter unmanned aircraft systems

DVE = Domestic Violent Extremist

OCIO = Office of the Chief Information Officer

UAS = unmanned aircraft systems

a DBT-DOE Order 470.3C, Design Basis Threat (DBT).

b CSTART-Center for Security Technology, Analysis, Response and Testing - Established under Section 3116 of the FY 2014 

National Defense Authorization Act.

3.7.3 Information Technology and Cybersecurity

The DOE/NNSA Office of the Associate Administrator for Information Management and Chief Information 

Officer (NNSA OCIO) is responsible for Federal information management, IT, and cybersecurity for NNSA. 

The NNSA OCIO has implemented an organizational structure that supports its functions under three 

organizations: the Office of Information Technology, the Office of Cybersecurity, and the Office of Mission 

Integration to effectively achieve its mission.

The IT and Cybersecurity program provides information management, IT, and cybersecurity support to 

the nuclear security enterprise through investments in cybersecurity capabilities, cloud-based 

technologies, and IT infrastructure. The NNSA OCIO enhances the nuclear security enterprise’s

information management through using a combination of technology, policy, and risk management 

practices. NNSA OCIO leverages new and existing technologies to assist and protect DOE and NNSA 

nuclear missions in an increasingly complex cyber environment. It also collaborates and coordinates with 

the DOE’s Office of the Chief Information Officer on IT and cybersecurity solutions development and 

deployment to protect DOE information and information assets. 

The major elements of the IT and Cybersecurity program, supported by Mission Integration, are illustrated 

in Figure 3–5.

Figure 3–5. Information Technology and Cybersecurity major elements and initiatives
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3.7.3.1 Status

3.7.3.1.1 Significant Changes Since the Last Stockpile Stewardship and Management Plan

The NNSA OCIO continues to make enhancements to the Enterprise Secure Network infrastructure, and 

additional IT modernization, with an emphasis on addressing risks related to software assurance, 

operational technology (OT) assurance, and supply chain management. Due to the COVID-19 pandemic, 

the IT and Cybersecurity program has expanded its support boundary to be able to continue

accommodating working from home and for extensive videoconferencing, including classified 

videoconferencing for a large portion of the workforce.

3.7.3.1.2 The Current and Future Anticipated Mission Requirements

The need for agility is critical, as the required responses to the cyber environment necessitate constant 

monitoring and response and demand increasingly advanced technology to protect information.

3.7.3.1.3 Current State of the Infrastructure

The NNSA OCIO is currently modernizing the infrastructure to provide the best possible protection of 

information at the best level of service.

3.7.3.1.4 Current State of the Workforce

The NNSA OCIO acknowledges the challenges of recruiting and retaining top talent due to competition for 

IT and cybersecurity resources, especially in a pandemic situation. It 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, the NNSA OCIO will continue to be a competitive employer that can recruit, develop, and 

retain top talent in the IT and cybersecurity workforce.

3.7.3.2 Challenges and Strategies

The highly complex and global nature of 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 

landscape and to respond rapidly to the evolving and most sophisticated threats. Table 3–16 provides a 

high-level summary of Information Technology and Cybersecurity challenges and the strategies developed 

to address them.

Table 3–16. 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, 

without modification.

Move toward centralized purchasing and 

equipment review before issuing equipment 

to the field will address current supply chain 

and software assurance issues.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.

Insider Threat Work with counterintelligence on 

implementing an insider threat program, 

concentrating first on the classified arena.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.
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Challenges

Strategies

Current Strategy Being Implemented Future Strategies 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.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.

Identify, inventory, and ensure proper 

cybersecurity hygiene is applied to OT 

such as Industrial Control Systems and 

wireless technologies across all 

spectrum bands.

• 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.

The current strategy is evolving and 

these processes’ maturity will need to 

adapt to the constantly changing 

threat/risk environments.

Current network monitoring services 

restrictions

• Upgrade sites across the enterprise 

through deploying new cybersecurity 

solutions.

• Ensure all networks, IT, and OT systems 

are monitored by the new demilitarized 

zone.

The current strategy is sufficient. 

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 NNSA complex.

Continued investment is needed in network 

communications systems and in the central 

networking and telecommunications 

facilities.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.

Program effects from 2022 Nuclear 

Posture Review Implementation

• Resource requirements for IT and 

cybersecurity that are required to 

support the nuclear security enterprise 

mission will vary directly with any 

increases in weapons program 

workloads.

• Adding work locations, increasing 

workforce numbers, and adding shifts will 

result in additional demand for IT and 

cybersecurity resources to ensure a 

secure, protected, and innovative work 

environment.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.

Fill critical cybersecurity and IT 

vacancies across the enterprise.

Hire a workforce that has the skillsets

needed per NNSA’s OCIO 2020–2023

Strategic Plan Principle 6: Invest in 

employee development to cultivate a highperforming workforce that will support 

NNSA’s mission today and into the future.

The current strategy is sufficient. 

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.

The current strategy is sufficient. 

However, ongoing threat analysis will 

determine whether further strategies 

are needed.

Fully adopt cybersecurity 

improvements identified in Executive 

Order 14018 (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.

The current strategy is evolving and 

these processes’ maturity will need to 

adapt to the constantly changing 

threat/risk environments.

Accommodate current and future 

teleworking needs across the NNSA 

complex.

Developed and implemented services and 

solutions to provide operational 

connectivity during COVID-19.

Continue planning efforts to ensure 

services and solutions are available to 

enable operational connectivity 

beyond COVID-19. 

Artificial Intelligence/Machine Learning • Develop an artificial intelligence/machine 

learning 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.

IT = information technology

OCIO = Office of the Chief Information Officer

OMB = Office of Management and Budget

OT = operational technologies

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Chapter 4

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 labs, plants, and sites. These factors 

present many complex challenges, particularly given 

DOE/NNSA’s aging infrastructure. Despite these 

challenges, and with congressional support, 

DOE/NNSA has increased the resources allocated to 

and made significant progress in modernizing its 

infrastructure, eliminating excess facilities, and 

improving management practices.

This chapter provides a broad view of infrastructure 

and operations across the nuclear security enterprise

and shows how DOE/NNSA conducts infrastructure 

planning and management to capture infrastructure 

activitivies that support multiple capabilities, such as 

mission enabling construction, minor construction,

and sustainment activities. This chapter also 

addresses how infrastructure supports the Weapons 

Activities capability areas discussed in Chapter 3. 

Infrastructure is an essential element of each 

capability, as shown in Figure 3–2, and as mentioned

in the capability sections of each key capital project in 

Chapter 3. 

Figure 4–1 illustrates the size 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 full spectrum of asset types, resulting in balanced enterprise investment decision-making 

across the entire asset management life cycle, as shown in Figure 4–2. Planning initiates an asset’s life 

cycle, 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. This chapter 

describes these life cycle asset management activities.

Infrastructure and Operations 

Major Accomplishments

• Completed construction of the New Albuquerque 

Complex providing 333,000 square feet of modern 

office space for 1,200 employees.

• Completed construction of the Lawrence 

Livermore National Laboratory (LLNL) B225 

Manufacturing Science Building providing a new 

polymer manufacturing capability supporting the 

W80-4 Life Extension Program (LEP) and W87-1 

Modification Program.

• Executed NNSA’s first-ever “option to purchase” 

acquisition providing a timely and cost-effective 

solution with high-bay, lab, and office space to 

support the Y-12 National Security Complex 

(Y-12) Development mission.

• Completed construction of a modern, state of the 

art new Data Center (Building C902) providing a 

high-capacity and resilient facility supporting 

growing operations across Sandia National 

Laboratories (SNL)-California. 

• Completed construction of the LLNL Emergency 

Operations Center.

• Completed construction of the TA-5 Substation 

providing increased electrical capacity to Los 

Alamos National Laboratory (LANL). 

• Completed construction of the Exascale 

Computing Facility Modernization project at LLNL 

to accommodate the increased infrastructure 

demands of exascale computing platforms.
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Figure 4–1. DOE/NNSA infrastructure size and scope

Figure 4–2. Asset management life cycle
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The asset management life cycle model shown in Figure 4–2 illustrates the different types of investments 

across various funding sources and sponsoring programs. Sections 4.1 through 4.4 describe the activities 

within the asset management model. Infrastructure planning and asset management, described in 

Section 4.1, estimates future repair and modernization investments in facilities as they age, forecasting 

facility replacement schedules, planning for new and replacement acquisitions, and anticipating the 

disposition needs and excess facilities’ costs for completion in a timely manner.

Sections 4.2 and 4.3 describe acquisition strategies as well as modernization and sustainment activities 

for existing facilities that support capabilities needed to sustain the stockpile. Section 4.2 discusses the 

plansfor programmatic construction by area and the actions being taken to sustain, recreate, and improve 

the capabilities detailed in Chapter 3. Section 4.4 addresses disposition of excess facilities. Sections 4.2 

through 4.4 also discuss a wide range of programs, processes, and funding types, which reflect the 

complexity of aligning investment needs to funding sources.

Facility acquisition occurs through line-item projects, minor construction, purchase, or leasing. Operating, 

maintaining, and revitalizing existing facilities are funded through minor construction, recapitalization, 

maintenance, and other programs. The funding strategy to support any given type of project can vary 

greatly due to the project’s size, scope, and other factors.

In addition to modernizing DOE/NNSA’s physical infrastructure that directly supports the Weapons 

Activities programs, continuous investments are required to sustain and modernize both critical physical 

security and cybersecurity elements across the nuclear security enterprise. 

4.1 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, and

strategic investment planning for major system upgrades and 

replacements. 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. Previous 

capital planning efforts gave insufficient consideration to the long-term infrastructure needs in 

sustaining/renewing existing assets, and future needs tied to emerging capabilities and anticipated future 

workloads. DOE/NNSA’s most recent integrated strategic planning efforts have yielded a much more 

realistic and time-critical view of out-year infrastructure needs to support the mission and long-term 

sustainment of capabilities. The processes for identifying and planning for these long-term needs are now 

greatly improved and expanded.

Direct mission needs have been better integrated with routine infrastructure sustainment and renewal 

processes to create a clearer, more comprehensive plan for long-term investments. Bottom-up planning 

across the nuclear security enterprise has been improved through area planning, described below, and 
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deep dive reviews. Asset management software has provided 

accessible data for earlier maintenance and sustainment needs 

planning. Because of this expanded, more integrated planning, 

DOE/NNSA has a more 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 much more closely with industry standards. The 

asset management life cycle, shown in Figure 4–2, is the basis 

for all investment planning within DOE/NNSA. It can be applied 

to a single facility or, if applied to numerous facilities, can be 

used to organize the way the infrastructure program operates. 

The elements of the cycle must remain in balance to keep the 

nuclear security enterprise assets healthy. While the model 

appears straightforward, the processes employed to achieve balance across multiple facilities for the 

purpose of meeting multiple competing priorities are not. In the DOE/NNSA environment, decisionmaking is complicated by multiple funding mechanisms, guidance, and requirements. This section 

includes definitions of terms and background to aid in understanding these intricacies and the nuclear 

security enterprise’s broad extent of investment planning and execution.

4.1.1 Area Planning

The newest element of DOE/NNSA’s planning process is area planning, which connects plans to projects 

for achieving DOE/NNSA’s Strategic Vision for the future nuclear security enterprise. The area plans

provide detailed information on the life cycle management strategies of co-located or functionally similar 

facilities, buildings, and other structures. 

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 aligned with DOE/NNSA mission 

needs. Area plans blend multiple funding sources and are regularly updated to reflect the latest 

developments and priorities.

DOE/NNSA and its M&O partners have been developing area plans, representing assets and associated 

capabilities 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 and weapon components to utilities 

and emergency services. When viewed collectively, area plans provide a roadmap for modernizing

DOE/NNSA infrastructure to deliver the mission.

4.1.2 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

(FYNSP) programming and budgeting process as projects reach appropriate milestones.

Infrastructure Deep Dives 

DOE/NNSA holds meetings with each 

management and operating (M&O) partner 

site to discuss mission requirements, related 

infrastructure needs, asset condition and life 

cycle management, and proposed 

investment plans. 

Deep dives lay the foundation for prioritized, 

integrated area plans and a Master Asset 

Plan for the nuclear security enterprise. 
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Programmatic infrastructure investments are linked to 

mission-specific functions 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 nearterm and for the foreseeable future.

Consolidating line-item investment proposals combines

multiple current data collection processes and ensures a 

consistent, repeatable planning process for all line-item

construction projects. The program offices’ comprehensive 

review of project proposals ensures all current and proposed 

line-item construction projects (detailed in Sections 4.2.1–

4.2.2) represent necessary investments to support the program of record. The cost estimation process 

for proposals within capital acquisition is described in Chapter 5, Section 5.9.3.

4.1.3 Critical Decision Acquisition Milestone Process

A basic understanding of DOE’s Critical Decision (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, Program and Project Management for the Acquisition of Capital 

Assets, 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 

in order to progress to the next stage. Figure 4–3 shows the four phases of the CD process (Initiation, 

Definition, Execution, and Closeout), with their corresponding CD stages.

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.

1

 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 approval of CD-4 is 

predicated on the readiness to operate and/or 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.

1 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.

DOE/NNSA Capital Construction Levels

Line-item – a capital project greater than $25 

million, so-called because it has its own line 

in DOE/NNSA’s budget structure.

Minor Construction – a construction project 

less than $25 million that includes projects 

also referred to as General Plant Projects, 

Institutional General Plant Projects, and 

Accelerator Improvement Projects.

Institutional General Plant Project – 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.

General Plant Project – a miscellaneous 

minor construction project of a general 

nature, for which the total estimated cost may 

not exceed the congressionally established 

limit.
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Figure 4–3. Critical Decision process

4.2 Acquisition

DOE/NNSA has more than 5,000 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. 

DOE/NNSA’s line-item construction portfolio requires 

consistent, stable, and timely funding. The size and 

complexities of these projects present several program and 

project management challenges. However, DOE/NNSA has 

demonstrated success despite the complexity of the 

DOE/NNSA acquisition processes and the challenge of meeting enterprise needs in a responsive and timely 

manner.

Since aging facilities represent increasing risk to mission execution, 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 4–4 demonstrates 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 presented here varies from similar charts in previous Stockpile Stewardship and 

Management Plans (SSMPs) as the average age calculation was expanded from using a few hundred 

representative programmatic facilities to all DOE/NNSA facilities.
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Figure 4–4. 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 (formerly termed portfolio), 

followed by mission-enabling line-items.

4.2.1 Programmatic Construction

Programmatic construction projects are categorized according to the Weapons Activities capability areas, 

which are detailed in Chapter 3. Sections 4.2.1.1–4.2.1.7 describe current and proposed line-item projects 

within each capability area, including their projected schedules and cost ranges. Project proposals 

(Pre-CD-0) represent potential mission gaps and emerging requirements across the nuclear security 

enterprise. They require additional vetting before DOE/NNSA moves forward with addressing the gap

with a material solution. The projected schedules and cost ranges shown represent one potential planning 

scenario and may change in future SSMPs as stockpile and enterprise requirements are refined.

4.2.1.1 Weapon Science and Engineering

Line-item projects in the Weapon Science and Engineering area encompass the suite of physical sciences 

and engineering disciplines that comprise the theoretical and experimental capabilities needed to assess 

the current nuclear stockpile and design and certify future stockpile weapons. Current planning estimates 

and schedule dates for projects in this area are listed in Figure 4–5. Plans for the sustainment of the Z 

pulsed power facility (Z) and Omega Laser Facility (Omega) are not included in this figure because they 

are not proposed as line-item projects. 
Department of Energy/National Nuclear Security Administration | April 2023

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Figure 4–5. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Science and Engineering

DOE/NNSA is currently executing three programmatic line-item construction projects in the Weapon

Science and Engineering area that are past CD-1. Cost and schedule estimates for these projects vary from 

conceptual design-based estimates to baselined project estimates:

◼ The High Explosive Science and Engineering (HESE) Facility will construct three new buildings to 

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-2/3 approval in April 2022. Site preparation and long-lead procurement activities started at 

the beginning of fiscal year (FY) 2021. Main works construction started in May 2022.

◼ The Advanced Sources and Detectors project is an MIE2that 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 the U1a Complex.

◼ The U1a Complex Enhancements Project (UCEP) will provide infrastructure modifications to the 

U1a Complex at the Nevada National Security Site (NNSS) to house and field multi-pulse 

radiography. This project includes structures, systems, and components necessary for deploying 

2 MIEs are capital equipment with a cost that exceeds $5 million. In most cases, capital equipment is installed with no construction 

cost. However, in cases where the equipment requires supporting construction provision, the associated construction activities 

must be acquired through a line-item construction project, or a minor construction project if the cost is below the minor 

construction threshold established by Congress. MIEs follow a similar CD process as line-item capital asset projects. See DOE 

Order 413.3B for additional details.
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Enhanced Capabilities for Subcritical Experiment Advanced Sources and Detectors Project’s 

pulsed X-ray radiography equipment. It also includes support systems for potential future 

neutron-diagnosed subcritical experiments technology, which will produce valuable data on the 

neutron behavior of aged plutonium and other phenomena associated with the final stages of a 

weapon implosion.

The following programmatic line-item project in the Weapon Science and Engineering area is in the 

Definition Phase of the CD process (CD-0 to CD-1):

◼ The Energetic Materials Characterization (EMC) project will support research and development 

(R&D) to advance predictive capabilities for safety and performance assessments and 

qualification and surveillance, evaluate material responses to all phases 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 into a single modern facility to increase operational efficiency and reduce operating 

costs.

In addition to projects in the Definition and Execution Phases, DOE/NNSA is considering several 

programmatic line-item proposals in the Weapon Science and Engineering area (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. Descriptions of scope should be considered illustrative, as 

alternative selections will not be made until each project completes an Analysis of Alternatives (AoA) and 

the project achieves CD-1:

◼ The Los Alamos Neutron Science Center (LANSCE) Modernization Project (LAMP) would be a 

one-time capital investment to replace the front end of the LANSCE accelerator. This would

eliminate end-of-life and obsolete components to improve reliability, availability, maintainability, 

efficiency, and safety, and would allow LANSCE to support assessment and certification, which is 

required through at least 2050.

◼ The National Ignition Facility (NIF) Laser and Experimental System Revitalization is part of a 

broader effort of NIF sustainment aimed at refurbishment, recapitalization, and improvement of 

the NIF facility. This project would support revitalization of the laser systems as part of the 5-year 

plan to ensure NIF continues to deliver for the Stockpile Stewardship Program.

◼ The Increased Laser Power and Energy on 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 Building 851 Next Generation Cinematographic Moderate Energy Radiography Capability

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.

◼ The Radiological Science Capability project would consolidate and relocate the aging radiological 

facilities that support Los Alamos National Laboratory (LANL) weapons and global security mission 

requirements. The planned replacement facility would support critical missions including 
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weapons programs, nuclear forensics, and nonproliferation programs, as well as broad science 

capabilities (e.g., actinide separation and synthetic chemistry).

◼ 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. 

◼ The Next Gen Pulsed Power facility is a significant long-term goal of the DOE/NNSA’s Inertial 

Confinement Fusion program to fill a capability gap in the environments currently accessible at

facilities such as NIF, Z, and Saturn. The Next Gen Pulsed Power facility would have increased

efficiency and effectiveness and would modernize infrastructure dedicated to HED experiments.

◼ The Dual-Axis Radiographic Hydrodynamics Test (DARHT) Facility Modernization would be a 

series of activities to ensure continued reliable and resilient high-quality data returns at DARHT. 

These upgrades would sustain delivery of foundational data for stockpile stewardship and global 

security.

◼ The Building 801A Advanced Radiographic and Diagnostics Hydrodynamic Test Building 

Upgrade project would build a second-axis with a multi-frame cinematographic capability for 

imaging weapon physics configurations over a range of densities. The project would use the 

existing Contained Firing Facility and would add non-bunker laboratory space to house an active 

reset linear induction accelerator or laser based multi-frame radiographic source.

◼ The 3D Time Resolved Hydrodynamic-Radiography in a Laser-Explosives Application Facility 

Replacement project would build a new facility capable of multi-axis, multi-frame imaging of 

surrogate nuclear weapon-relevant dynamic experiments to meet a wide range of experimental 

goals, including tomographic reconstruction. The flexibility, resolution, and information content 

that would be afforded by this laser-driven X-ray source is not possible in existing facilities.

4.2.1.2 Weapon Simulation and Computing

Line-item projects in the Weapon Simulation and Computing area enable high performance computing 

(HPC) and development of the weapons codes, models, and data analytics used to design and assess 

nuclear weapons systems’ and components’ behavior. Current planning estimates and schedule dates for 

projects in this area are listed in Figure 4–6.

Figure 4–6. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Simulation and Computing
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DOE/NNSA recently completed a project in the Weapon Simulation and Computing area:

◼ The Exascale Computing Facility Modernization (ECFM) 

project modified the existing HPC center at LLNL to 

accommodate the increased infrastructure demands of 

exascale computing platforms, including upgrades to the 

facility’s electrical, cooling, and mechanical capabilities. The 

existing cooling tower complex was expanded for additional 

cooling, and the electrical system was upgraded to allow 

additional power for HPC. The project was completed in 

May 2022.

There are no projects in the Execution or Definition Phases in the Weapon Simulation and Computing

area. DOE/NNSA is considering one programmatic line-item proposal in the Weapon Simulation and 

Computing area (Pre-CD-0). This project proposal is in the planning process but should not be considered 

a part of the program of record until it achieves appropriate approvals. The description of scope should 

be considered illustrative, as alternative selection will not be made until the project completes an AoA

and the project achieves CD-1:

◼ The Engineering-Data Analytics Facility (EDAF) project would construct a new HPC facility that 

would enable data collection, storage, and analysis capabilities by bringing together HPC systems, 

high-performance data-analytics systems, a scalable data enclave, and an extreme-speed 

network-backbone to deploy these capabilities and enable a future of full-system engineering 

models.

4.2.1.3 Weapon Design and Integration

Line-item projects in the Weapon Design and Integration area support the capabilities needed to research, 

design, test, analyze, qualify, and integrate components and subsystems into weapon systems that will 

meet all military requirements and endure all predicted environments. Current planning estimates and 

schedule dates for projects in this area are listed in Figure 4–7.

Figure 4–7. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Design and Integration

The following programmatic line-item project in the Weapon Design and Integration area is in the 

Definition Phase of the CD process (CD-0 to CD-1):

◼ 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 

Upgraded cooling and electrical capabilities 

upon the completion of ECFM at LLNL
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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. 

However, ACRR is nearly 60 years old, was not designed to house a nuclear reactor, and does not 

meet modern codes or standards. 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 optimized 

to meet current and future stockpile modernization needs.

In addition to the project in the Definition Phase, DOE/NNSA is considering a number of programmatic 

line-item proposals in the Weapon Design and Integration area (Pre-CD-0). These project proposals are 

in the planning process but should not be considered part of the program of record until they achieve 

appropriate approvals. The descriptions of scope should be considered illustrative, as alternative 

selections will not be made until the projects complete an AoA and the project achieves CD-1:

◼ The New Next Generation Life Extension Program R&D Component Fabrication Facility 

(NextGen Fabrication Facility) would be a joint design agency-production agency (DA-PA) 

pre-production testbed that could assess, develop, tailor, and transition new manufacturing 

technologies. This would provide DOE/NNSA with a capability to accelerate the development and 

production of non-nuclear components into the weapon modernization process. This joint DA-PA 

owned collaborative space would enable faster and more frequent design iterations to mature 

the definition and production processes for production of non-nuclear components, resulting in 

accelerated time to first production unit for future modernization programs.

◼ The Heterogeneous Integration Facility (HIFac) capability would provide DOE/NNSA an enduring 

supply of trusted strategic radiation hardened microsystems to meet future system functional, 

environmental, and assurance requirements. Meeting these requirements would likely require 

the integration of a suite of future products, including semiconductor components, 

microelectromechanical systems, and photonics components. Heterogeneous Integration would

improve cost efficiency and reliability through flexibility in combining custom-built and 

commercially available state-of-the-art technologies.

◼ The Gas Transfer Systems and Surety Laboratory (GTS/S) project would meet GTS and Surety 

mission requirements in the future. The GTS and Surety project would provide a modern, 

lower-maintenance structure capable of meeting the expanded, future demands of the program. 

Work areas and equipment would be upgraded with an efficient layout and state-of-the-art 

technology to meet current and specific testing requirement needs.

4.2.1.4 Weapon Material Processing and Manufacturing

Line-item projects in the Weapon Material Processing and Manufacturing area are related to the 

packaging, processing, handling, and/or manufacturing of plutonium, uranium, tritium, energetic and 

hazardous materials, lithium, and other metal and organic materials needed for nuclear weapons. Current 

planning estimates and schedule dates for projects in this area are listed in Figure 4–8.
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Figure 4–8. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Material Processing and Manufacturing 

DOE/NNSA is currently executing multiple programmatic line-item projects in the Weapon Material 

Processing and Manufacturing area that are past CD-1. Cost and schedule estimates for these projects 

vary in maturity from conceptual design-based estimates to baselined project estimates.

◼ 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 Plutonium Facility (PF-4) at LANL to increase throughput to no less than 30 pits 

per year (ppy). LAP4 achieved CD-2/3 for the Decontamination and Decommissioning subproject 

in the first quarter of FY 2022. Additionally, CD-3A and CD-3B were approved for long lead 

procurement of gloveboxes to support the 30 ppy base equipment installation subproject.

◼ 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 to support pit production and Plutonium Center of Excellence missions. 

Active subprojects include reconfiguring space in the Radiological Laboratory Utility Office 

Building and in PF-4, and installing additional analytical chemistry and materials characterization 

equipment.

◼ The Uranium Processing Facility (UPF)3 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, is poorly configured to meet 

today’s strategic needs, and poses multiple risks to meeting the mission.

3 The original baseline date for the Uranium Processing Facility CD-4 approval of December 2025 is under review.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-14

Manhattan Project-era Building 9212 at Y-12 (left) and construction on its replacement,

the Uranium Processing Facility, in April 2022 (right)

◼ The Transuranic Liquid Waste Facility (TLW) will support transuranic liquid waste treatment, 

which is a key support capability for DOE/NNSA operations at PF-4. The current facility that treats 

liquid waste is past its useful life and does not meet current codes and 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.

◼ The Technical Area 55 (TA-55) Reinvestments Project (Phase 3) has begun and supports design 

and construction for new fire alarm systems and removal of the old system in PF-4 at LANL. Due 

to the old system’s age, replacement parts are no longer readily available, adding risks to the 

program.

◼ The Savannah River Plutonium Processing Facility (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 I/Hazard 

Category II4structure that provides an opportunity to achieve pit production in a facility designed 

to meet stringent security and safety requirements for plutonium operations. SRPPF will provide 

a sustained production capacity of no fewer than 50 War Reserve ppy as close to 2030 as possible 

at Savannah River Site (SRS). The project achieved CD-1 in FY 2021.

◼ The High Explosives Synthesis, Formulation, and Production Facility (HESFP) project will 

establish HE production capability within the nuclear security enterprise to address the current 

domestic supply’s inability 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 and plans for a CD-3A approval in 

FY 2024.

◼ The Lithium Processing Facility (LPF) will construct a new facility to replace Y-12 Building 9204-2. 

At 79 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 

4 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. 
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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, providing geotechnical information in support of facility design, have commenced.

◼ The Tritium Finishing Facility (TFF) project will construct two new processing buildings and 

relocate the vulnerable reservoir-related capabilities from the current 65-year-old facility to the 

newer, centralized facilities. This alternative will significantly reduce operational risk and increase 

facility reliability when compared to continuing operations in the current facility for an additional 

20 years.

The Weapon Material Processing and Manufacturing area has one line-item project 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.

In addition to projects in the Definition and Execution Phases, DOE/NNSA is considering one programmatic 

line-item proposal in the Weapon Material Processing and Manufacturing area (Pre-CD-0). This project 

proposal is in the planning process but should not be considered a part of the program of record until it 

achieves appropriate approvals. The description of scope should be considered illustrative, as alternative 

selection will not be made until the project completes an AoA and the project achieves CD-1:

◼ The Depleted Uranium Manufacturing Capability (DUMC) project would support several 

processes for creating binary feedstock and manufacturing components to meet component 

deliveries in support of weapons modernization programs. These processes include casting and 

alloy fabrication, pressing, forging, machining, and inspection. Updating the processing methods 

and right-sizing the facility for current and foreseeable production needs would result in a 

significant reduction in the footprint defined by the existing facilities.

4.2.1.5 Weapon Component Production

Line-item projects in the Weapon Component Production area support the research, design, 

development, qualification, surveillance, manufacturing and production for all non-nuclear components 

and systems for nuclear explosive package weaponization. Current planning estimates and schedule dates 

for projects in this area are listed in Figure 4–9.

Figure 4–9. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Component Production
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The Weapon Component Production area has one line-item project in the Definition Phase of the CD 

process (CD-0 to CD-1):

◼ The Power Sources Capability 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 

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.

In addition to the project in the Definition Phase, DOE/NNSA is considering one programmatic line-item

proposal in the Weapon Component Production area (Pre-CD-0). This project proposal is in the planning 

process but should not be considered part of the program of record until it achieves appropriate 

approvals. The description of scope should be considered illustrative, as alternative selection will not be 

made until the project completes an AoA and the project achieves CD-1:

◼ 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.

4.2.1.6 Weapon Assembly, Storage, Testing, and Disposition

Line-item projects in the Weapon Assembly, Storage, Testing, and Disposition area support the safe and 

secure assembly, storage, testing, and disposition of weapon components. Current planning estimates 

and schedule dates for ongoing and proposed projects in this area are listed in Figure 4–10.

Figure 4–10. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Assembly, Storage, Testing, and Disposition

Two line-itemsin the Weapon Assembly, Storage, Testing, and Disposition area are in the Definition Phase 

of the CD process (CD-0 to CD-1):

◼ 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 
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capacities for the next 75 to 100 years. The facility will house weapons, pits, SRS surplus 

plutonium material, as/if needed, and Hanford Unirradiated Fuel Packages. It will include shipping 

and receiving docks for SNM, and for transporting weapons in the Mobile Guardian Transporter 

and Safe Secure Transport. This project has been placed on hold so that NNSA can address higher 

priority infrastructure projects.

◼ The Radiography/Assembly Capability Replacement (RACR) project will consolidate the existing 

assembly and radiography complex, consisting of over 17 World War II-era buildings. RACR will 

improve safety, security, schedules, and quality assurance, and decrease risk to the public, 

workers, and program. 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.

DOE/NNSA is considering two programmatic line-item proposals in the Weapon Assembly, Storage, 

Testing, and Disposition area (Pre-CD-0). These project proposals are in the planning process but should 

not be considered as part of the program of record until they achieve appropriate approvals. The 

descriptions of scope should be considered illustrative, as alternative selections will not be made until the 

projects complete an AoA and the project achieves CD-1:

◼ The Integrated Weapon Evaluation Capability (IWEC) project would consolidate testing facilities 

for a faster and more efficient testing process and improve NNSA’s test development capability 

at Sandia National Laboratories (SNL). Facility investment would provide secure high-bay, 

mid-bay, and light electrical laboratories; collaboration space; and general office space. This 

project would involve co-locating DOE/NNSA's IWEC equipment. Commonality would reduce 

development cycle time and cost.

◼ The Weapon System Assembly and Disassembly Cell Upgrade project would fill a throughput and 

capacity mission gap. By modernizing the infrastructure needed to improve production cell 

capacity, DOE/NNSA would be poised to support the anticipated workload increase during other 

infrastructure construction projects.

4.2.1.7 Transportation and Security

Line-item projects in the Transportation and Security area support protecting all aspects that are critical 

to the nuclear security enterprise’s function. The Secure Transportation capability within this area has no 

current or proposed line-item projects. The projects listed below support the Physical Security capability, 

which protects all nuclear materials, infrastructure assets, and the workforce at DOE/NNSA sites that are 

involved in Weapons Activities programs and operations. Current planning estimates and schedule dates 

for projects in this area are listed in Figure 4–11.

Figure 4–11. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Transportation and Security
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DOE/NNSA is currently executing one programmatic line-item construction project in the Transportation 

and Security area that is past CD-1. Cost and schedule estimates for this project vary from conceptual 

design-based estimates to baselined project estimates:

◼ 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 Environmental Management cleanup activities for facilities 

previously encompassed by the larger protected area may proceed more efficiently and 

cost-effectively because those facilities will no longer be in a protected area. The project received 

CD-2/3 approval in January 2021 and is anticipated to reach CD-4 in FY 2025.

In addition to the project in the Execution Phase, DOE/NNSA is considering one programmatic line-item 

proposal in the Transportation and Security area (Pre-CD-0). This project proposal is in the planning 

process but should not be considered a part of the program of record until it achieves appropriate 

approvals. The description of scope should be considered illustrative, as alternative selection will not be 

made until the project completes an AoA and the project achieves CD-1:

◼ The New Physical Security and Central Alarm Station (CAS) Facility Replacement and 

Consolidation project would provide a new two-story facility that would house multiple security 

groups including the 24/7 CAS.

4.2.2 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 deterrence mission (see Figure 4–12). These 

projects are required to meet daily operational needs across the nuclear security enterprise.

Three mission enabling line-item projects were recently completed:

◼ The Albuquerque Complex Project provided new office space and was constructed on DOE 

property in Albuquerque, adjacent to Kirtland Air Force Base. The current DOE/NNSA 

Albuquerque Office Complex is beyond its design life and does not meet DOE/NNSA’s mission 

needs. Construction was completed on a 333,000-square-foot building to house approximately 

1,200 employees. The new building is designed to Leadership in Energy and Environmental Design

(LEED) Gold Standards.

◼ The Technical Area 3 (TA-3) Substation Replacement at LANL provides increased distribution 

capacity, improved reliability, reduced maintenance, support for greater operational flexibility, 

and increased worker safety. It provides separate power feeds to LANL and Los Alamos County.

◼ The Emergency Operations Center at 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 allows an occupancy rate 

needed during an emergency event that the previous Emergency Operations Center could not

accommodate, provides additional parking, and contains or interfaces with approximately 60

systems, including closed-circuit television, metrology, site fire and life safety alarms, radio 

communication, emergency services disaster dispatching, etc.
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-19

Figure 4–12. 25-year mission-enabling line-item schedule

The Enhanced Minor Construction Commercial Standards pilot is a new initiative to increase buying power 

and accelerate delivery for non-complex, non-nuclear, commercial facilities line-item construction 

projects less than $50 million. The pilot aims to attract more competitive bidding and reduce project and 

contract management costs, while delivering a quality facility that meets the program requirements.

There are currently three projects in the pilot, with a fourth, the Emergency Operations Center at LLNL, 

completed in March 2022.

◼ The Fire Station project at Y-12 provides a single-story building (approximately 35,000 square 

feet) 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 the Y-12 site. 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 that includes

large fire apparatus vehicles, ambulances, emergency response vehicles, and other support 

vehicles. Construction began in FY 2021 and beneficial occupancy is planned for completion in 

FY 2023.
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-20

◼ The Emergency Operations Center at Y-12 will provide 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. 

Construction began in FY 2021 and beneficial occupancy is planned for start of operations in 

FY 2023.

◼ 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. The center is expected to be operational in spring 2023.

Digital rendering of SNL’s new Emergency Operations Center

Construction at the Emergency Operations Center at Y-12
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-21

The mission enabling projects listed below are following DOE Order 413.3B CD processes and are currently 

in the Execution Phase.

◼ The 138kV Power Transmission System Replacement project will replace a 55-year-old 

138-kilovolt (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 23 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 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.

◼ 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 Electrical Power Capacity Upgrade at LANL will address projected increases in the electrical 

transmission and distribution system’s capacity at LANL to reliably support demand for multiple 

program activities being performed at the site. By 2024, 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.

There are multiple proposals for new mission enabling projects that are planned over the next 10 to 

25 years, including those listed below. With the exception of the Special Materials Facility, the 

descriptions of scope should be considered illustrative, as alternative selections will not be made until the 

projects complete an AoA and the project achieves CD-1:

◼ The Special Materials Facility (SMF) Utilities and Infrastructure Sub-project will provide 

infrastructure and utility upgrades to Building 9225-03 at Y-12. This repurposed facility is 

necessary to support special materials processing and production for future mission 

requirements.

◼ 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. 

◼ 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 Office Space at Kansas City National Security Campus (KCNSC) would provide office space for 

additional staff supporting increased production capacity for planned requirements. Current 

facilities do not have the capacity to house the forecasted workforce for the production of

non-nuclear components for multiple programs.
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-22

◼ The National Security Innovation Center at LLNL would collocate staff in dispersed, end-of-life 

Weapons Program office buildings into a more centralized location and would enable optimized 

use of space. 

◼ 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.

◼ The Northwest Las Vegas New Office Space at NNSS would provide sustainable infrastructure 

that supports the health, safety, and welfare of NNSS employees, the public, and the 

environment.

4.3 Modernization and Sustainment

This section describes how DOE/NNSA, in partnership with its M&O

partners, modernizes and sustains 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.

Modernization can be done through minor construction and 

recapitalization projects, which are important vehicles for DOE/NNSA to 

sustain major facilities and replace smaller capital assets below the $25 

million minor construction

threshold. These projects 

are an effective method for 

making improvements to 

increase DOE/NNSA’s mission performance and lower 

operating costs. They typically 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 General Plant Projects, 

Institutional General Plant Projects, and 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. This 

investment method is used in conjunction with line-item construction to provide timely, appropriately 

sized, and integrated infrastructure solutions.

Security Infrastructure Revitalization 

Program (SIRP)

SIRP was created by DOE/NNSA’s Office 

of Defense Nuclear Security (DNS) to 

assure the strength of the physical security 

infrastructure supporting the DOE/NNSA 

mission. DNS developed and submitted to 

Congress a long-range Physical Security 

Systems Refresh Plan to outline and guide 

the scope of the SIRP effort. This plan 

contains a comprehensive condition 

assessment of the security infrastructure 

and a nuclear security prioritized listing of 

required upgrades. 
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-23

The following completed projects demonstrate that DOE/NNSA has directed infrastructure investments 

to address risks identified through facility and mission assessments: 

◼ Building 235 Chemistry Laboratories and Facility 

Revitalizations at LLNL (Recapitalization)

◼ Crystal Lab Revitalization at LANL (Recapitalization)

◼ DARHT Weather Enclosure at LANL (Recapitalization)

◼ Building 23 Tenant Improvements at KCNSC 

(Recapitalization)

◼ Data Center at SNL (Recapitalization) 

◼ Device Assembly Facility uninterruptible power supply

Upgrade at NNSS (Recapitalization)

◼ Provided redundant power to Pantex Data Center under 

the 12-37 Secondary Electrical Feed Installation project 

(Recapitalization)

◼ New Building 225 Manufacturing Science Facility at 

LLNL (Recapitalization)

◼ PF-4 High-Risk Variable Frequency Drive Fan Safety 

Replacement at LANL (Recapitalization)

◼ Installation of 7 Flame Detection System and 8 High 

Pressure Fire Loop lead-in replacements at Pantex 

(Recapitalization)

◼ New Z and TA-IV Missions Support Facility Building 972 

at SNL (Recapitalization)

◼ TA-72 Outdoor Range Upgrades Project at LANL 

(Defense Nuclear Security [DNS])

◼ Range Classroom Facility Replacement at LLNL (DNS)

◼ Zone 12 Outdoor Floodlight Replacement at Pantex (DNS)

◼ Zone 12 and 4 Enterprise Standard Booth Installation at Pantex (DNS)

◼ Building 224 Office Building at LLNL (Site Directed Investments)

◼ Building 223 Polymers and Engineering Facility at LLNL (Recapitalization)

◼ TA-33-0066 Building Extension at LANL (Site Directed Investments)

◼ Building 9117 Data Center Upgrades at Y-12 (Site Directed Investments)

◼ Roof Asset Management Program (Recapitalization): 27 projects at NNSA sites/1 project at a DOE 

site

◼ NM HV 5kV Overhead Feeder Replacements for overhead powerlines in TA-III at SNL 

(Recapitalization)

◼ NM Water System Secondary Feed to the 700KG Tank at SNL (Recapitalization)

New Z and TA-IV Missions Support Facility at SNL

Crystal Lab Revitalization at LANL

Data Center at SNL

Installation of Flame Detection System and HighPressure Fire Loop Lead-in Replacements at 

Pantex
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-24

◼ 234-H Main Side Diesel Generator Replacement at SRS 

(Recapitalization)

◼ Nuclear Facilities Electrical Modernization Portfolio at 

Y-12 (Recapitalization and Maintenance)

DOE/NNSA is also modernizing its infrastructure by executing 

its first option to purchase acquisition at 103 Palladium Way to 

house Y-12’s development capabilities. An option agreement 

is 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. 

This existing off-site facility, known as the John M. Googin Tech 

Development Facility, is near Y-12 and will provide a timely and 

cost-effective home for Y-12’s development mission. The 

facility is located on a secure and fenced 21-acre level campus 

with approximately 73,000 square feet of interior space. The building has extensive high-bay areas, 

wet-chemical laboratory areas, office areas, and already has the utilities necessary for a duplicate facility 

(100,000 square foot expansion) on the adjacent grounds. It was originally built as a secure facility to 

make medical isotopes in 1999 but was never occupied. With relatively little renovation, the facility can 

easily be adapted to house the compatibility and surveillance, materials processing, mechanical, control 

and sensor systems, and the metallurgical engineering and processing operations of Y-12 development. 

It is anticipated the building will provide a clean, safe, and modern facility for development that will assist 

in the recruitment and retention of the talented scientific and engineering staff that Y-12 requires for 

future success if this strategy is pursued.

Sustainment activities include maintenance and repair activities to sustain an acceptable condition of real 

property assets to perform their designated purpose or to mitigate risks. In some instances, the nature 

of core mission areas leads to direct programmatic sustainment funding for certain operations. These 

efforts support the recurring daily work needed to sustain plant, property, assets, systems, roads, and 

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.

These sustainment activities are executed through a combination of innovative tools that provide data for 

risk analyses that inform infrastructure management decisions. Decisions dedicate critical resources to 

maintaining facilities already in good condition and repairing the highest risks in DOE/NNSA assets.

4.4 Disposition

DOE/NNSA infrastructure that is no longer needed must be 

dispositioned to minimize risks to workers, the public, the environment, 

and the mission. 

Approximately 9 percent of assets located on DOE/NNSA’s sites are 

designated as excess. 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 

Nuclear Facilities Electrical Modernization 

Portfolio at Y-12

Main Side Diesel Generator Replacement at SRS
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-25

dispositioned. If a facility is process-contaminated, and the cost estimate for disposing of the facility 

exceeds $75 million, then DOE/NNSA must stabilize the facility until the DOE Office of Environmental 

Management can perform the disposition. The DOE/NNSA Disposition Strategic Plan outlines the details 

of how DOE/NNSA plans to address these excess facilities. 

Several completed projects demonstrate that DOE/NNSA has directed infrastructure investments to 

address risks identified through facility and mission assessments:

◼ Building 292 Deinventory at LLNL (Disposition)

◼ Ion Beam Equipment Removal at LANL (Disposition)

◼ Buildings 11-015A, 12-006B, 12-007, 12-007A, 12-014, 

12-017P1, 12-017P2, 12-019P, 12-024E, 12-024S, 12-030, 12-

R-034, 12-034, 12-034SS, 12-045, 15-051, and 16-031 at 

Pantex (Disposition)

◼ Buildings 9727-04, 9727-04A, 9409-34, and 9949-47 at Y-12 

(Disposition)

The longer an unused facility is left standing before demolition, the more deteriorated it becomes, and 

the more difficult it is to maintain in a safe shutdown condition. Aging facilities 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, nearly 700 additional assets with 4.2 million gross square feet are planned to 

become excess at DOE/NNSA sites. Of these assets, approximately 43 percent are process contaminated 

and may require DOE Office of Environmental Management expertise to demolish.

Building 11-015A at Pantex

Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-1

Chapter 5

Budget and Fiscal Estimates

The Fiscal Year (FY) 2023 President’s Budget for Weapons Activities supports the nuclear stockpile and 

associated modernization programs. The FY 2023 President’s Budget provides increase of 8.5 percent1

for the Department of Energy’s National Nuclear Security Administration (DOE/NNSA) and an increase of 

7.4 percent for Weapons Activities above the FY 2021 enacted appropriation. Throughout this chapter, 

the FY 2023 budget request is compared to the FY 2021 enacted budget to maintain consistency with the 

FY 2023 Congressional Budget Justifications. The FY 2023 Congressional Budget Justifications were 

prepared under a continuing resolution, prior to the enactment of the FY 2022 budget. 

DOE/NNSA developed the FY 2023 Future Years Nuclear Security Program (FYNSP) budget request for 

Weapons Activities by evaluating the resources necessary to support priority requirements and aligned

warhead programs to DOE/NNSA requirements. The assumptions encompassed by this request meet the 

timeline for DOE/NNSA’s warhead deliveries to be synchronized with the modernization of Department 

of Defense (DoD) delivery platforms.

The first part of this chapter displays budgetary information for the FY 2023 budget request based on the 

program of record described in the previous chapters of this Fiscal Year 2023 Stockpile Stewardship and 

Management Plan – Biennial Plan Summary (FY 2023 SSMP). Sections 5.4 through 5.8 compare the 

FY 2023 budget request to the FY 2021 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.

The second part of the chapter describes cost projections for selected programs beyond FY 2023, including 

the basis of those cost projections used to estimate the potential long-term cost of the DOE/NNSA 

Weapons Activities program. Cost-estimating techniques supporting the budget request are consistent 

with Government Accountability Office (GAO) best practices and 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.

5.1 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 considers the range of work 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 

1The percent change does not reflect the mandated transfer of $91.0 million in FY 2021 from Naval Reactors to the Office of 

Nuclear Energy for operations of the Advanced Test Reactor. 
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-2

and management and operating (M&O) contractor partners to ensure they reflect a complete set 

of requirements. This analysis drives the development of a budget that allows timely execution 

of key mission priorities and enables DOE/NNSA to achieve its mission.

◼ 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 OMB budget justification materials for the FYNSP that state 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 funding 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. The OMB 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.

At any time, multiple PPBE phases for different budget cycles are ongoing concurrently.

5.2 Portfolio Management

DOE/NNSA employs portfolios which are aligned with the budget, but are scope-based, to optimize its

risk-informed, complex, and time-constrained modernization and recapitalization efforts. 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. DOE/NNSA uses a rigorous portfolio management approach to determine the right set 

of programs and projects to accomplish that mission. 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.

Portfolio management enables DOE/NNSA to make necessary investments to advance existing capabilities 

and develop emerging capabilities for a strong nuclear deterrent. These capabilities underpin each of the 

Weapons Activities portfolios and are described in Chapter 3.

5.3 FY 2023 Future Years Nuclear Security Program

Weapons Activities provides maintenance and refurbishment of nuclear weapons to sustain confidence 

in their safety, reliability, and military effectiveness. In addition, Weapons Activities invests in scientific 

and engineering capabilities for assessment of the current stockpile warheads, qualification of 
Department of Energy/National Nuclear Security Administration | April 2023

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components for warhead modernization, and certification of warheads upon entry into the stockpile. 

Weapons Activities also provides maintenance and investment in DOE/NNSA’s infrastructure. 

The FY 2023 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 personnel growth 

in operations, physical security, and information technology (IT) and cyber security to support expanding 

program needs. In previous years, line-item construction projects were consolidated under the 

Infrastructure and Operations program. However, programmatic line-items in the FY 2023 FYNSP now 

reside under their respective program lines to reflect the Weapons Activities account integrator’s request 

for greater transparency with major construction projects.

Table 5–1 displays the FY 2021 and FY 2022 enacted budgets, and the program budget requests for 

Weapons Activities for FY 2023–FY 2027. The structure of the budget request in Table 5–1 reflects the 

major programs, not the capabilities discussed previously in Chapter 3. The figures and narrative that 

follow describe the FY 2023 budget request in more detail. 

Table 5–1. Overview of Future Years Nuclear Security Program budget request for

Weapons Activities in FY 2021–FY 2027a

Activity

FY (dollars in millions)

2021 

Enacted 

(Comp)

2022

Enacted 

(Comp)

2023

Request

2024

Request

2025

Request

2026

Request

2027

Request

Stockpile Management 4,290.2 4,637.7 4,929.1 4,967.2 4,943.5 4,778.6 4,914.3 

Production Modernization 3,903.5 4,156.9 4,640.6 5,157.6 5,245.4 5,027.2 4,612.6 

Stockpile Research, Technology, and 

Engineering 

3,003.5 2,978.0 2,894.7 3,066.8 2,937.7 2,892.5 2,975.0 

Infrastructure and Operations 2,542.1 2,487.4 2,631.0 2,775.0 2,842.7 2,893.9 2,972.1 

Secure Transportation Asset 348.7 330.8 344.4 354.7 381.0 389.0 442.1 

Defense Nuclear Security 789.1 844.1 882.3 927.6 955.3 991.5 1,049.2 

Information Technology and Cybersecurity 366.2 406.5 445.7 494.1 513.9 534.4 587.2 

Legacy Contractor Pensions and Settlement 

Payments

101.7 78.7 114.6 73.5 77.6 79.2 80.9 

Adjustments 0.0 0.0 (396.0) 0.0 0.0 0.0 0.0 

Weapons Activities Total 15,345.0 15,920.0 16,486.3 17,816.3 17,897.1 17,586.3 17,633.4 

a Totals may not add because of rounding. 

5.4 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). 

NEA, a new subprogram for FY 2023, will prevent, detect, and mitigate potential consequences of 

subversion to the stockpile and associated capabilities to design, produce, and assess nuclear weapons. 

Additional information about the Stockpile Management program can be found in Chapter 2, “Stockpile 

Management.”
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-4

5.4.1 Budget

The budget request for Stockpile Management increased 14.9 percent from the FY 2021 enacted budget

and is illustrated in Figure 5–1. 

Figure 5–1. FY 2023 President’s Budget Request for Stockpile Management

5.4.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

5.4.2.1 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) Program, (3) W80-4 LEP, (4) W87-1 Modification Program, and 

(5) W93 Program. 

The budget request for Stockpile Major Modernization increased to support:

◼ W87-1 transition from Phase 6.2, Feasibility Study and Design Options, to Phase 6.3, Development 

Engineering

◼ W93 ramp-up within Phase 2, Feasibility Study and Design Options

◼ W80-4 ramp-up of activities as the program transitions from Phase 6.3, Development Engineering,

to Phase 6.4, Production Engineering
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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-5

5.4.2.2 Stockpile Sustainment

Stockpile Sustainment directly executes maintenance, limited life component exchanges, minor 

alterations, 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.

The budget request for Stockpile Sustainment increased to support:

◼ The W76 Mk4B development and qualification

◼ Design, development, qualification, and production of weapon surety capabilities

◼ Implementation of Integrated Surety Architecture

◼ Development and deployment of product realization and digital engineering tools and 

applications

◼ Transition of the B61-12 into stockpile

◼ Joint Test Assembly flight test vehicle development and production

◼ High explosive component development and production

◼ Special material procurement supporting limited life components

◼ Activities supporting Air Force transition from Minuteman III to the LGM-35A Sentinel, previously 

referred to as the Ground Based Strategic Deterrent

5.4.2.3 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 warhead components that have been retired, while 

some limited number of components from the dismantled warheads are preserved for potential reuse in 

stockpile modernization and safety testing programs.

The budget request for Weapons Dismantlement and Disposition decreased due to a reduction in 

disposition of legacy component inventories.

5.4.2.4 Production Operations

Production Operations is a multi-weapon system manufacturing-based program that drives 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:

◼ Programmatic equipment maintenance activities previously funded under Infrastructure and 

Operations

◼ Kansas City National Security Campus (KCNSC) expansion and equipment relocation

◼ Hiring of critical skilled labor resources to support increase in production activities

5.4.2.5 Nuclear Enterprise Assurance

The FY 2023 budget request provides funding for this new subprogram, which actively manages 

adversarial subversion risks to nuclear weapons and associated design, production, and testing 
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capabilities. NEA enables the responsible use of digital technologies in the modernization of weapons, 

facilities, and engineering capabilities by preventing, detecting, and mitigating potential consequences of 

subversion. Through nuclear weapon digital assurance, NEA enables risk-managed adoption of leadingedge technologies to meet emerging military requirements and to reduce modernization schedules and 

costs.

5.4.3 Key Milestones

DOE/NNSA must meet the key Stockpile Management milestones in Figure 5–2

2

to sustain and modernize 

the stockpile. There is one major change from last year’s plan related to Stockpile Management: 

◼ The FY 2022 milestone, Begin Phase 6.4 activities for the W80-4 LEP, is delayed to FY 2023. 

DOE/NNSA is re-evaluating the W80-4 LEP schedule due to the Coronavirus Disease 2019 

(COVID-19), staffing, and technical program delays. Entry into Phase 6.4 will occur after the 

re-scheduled milestones are completed.

◼ The FY 2025 milestone, Deliver first production unit of the W80-4 LEP, was shifted to FY 2027 due 

to COVID-19 impacts, slow ramp-up in staff, and component technical delays. Due to the current 

margin between NNSA first production unit and Air Force Initial Operational Capability, NNSA has 

high confidence that it will support the Air Force’s scheduled Long Range Standoff cruise missile 

initial and final operational capability dates.

One milestone from last year’s Stockpile Stewardship and Management Plan (SSMP) completed in FY 2022 

is:

◼ Deliver first production unit of the B61-12 LEP

Figure 5–2. Key milestones for Stockpile Management

5.5 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 that sustain the Nation’s nuclear 

weapons stockpile: (1) Primary Capability Modernization, (2) Secondary Capability Modernization,

(3) Tritium Modernization and Domestic Uranium Enrichment, (4) Non-Nuclear Capability Modernization,

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 fiscal year; 

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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and (5) Capability Based Investments (CBI). CBI was funded under Infrastructure and Operations in prior 

year budget requests and now resides within Production Modernization.

5.5.1 Budget

The budget request for Production Modernization increased 18.9 percent from the FY 2021 enacted 

budget (comparable structure) and is illustrated in Figure 5–3.

Figure 5–3. FY 2023 President’s Budget Request for Production Modernization

5.5.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

5.5.2.1 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 Los Alamos Plutonium 

Pit Production Project (LAP4), the Technical Area 55 (TA-55) Reinvestment Project - Phase 3, Transuranic 

Liquid Waste Facility, Chemistry and Metallurgy Research Replacement, and the Savannah River 

Plutonium Processing Facility (SRPPF) are now included under Primary Capability Modernization to 
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encompass the full scope of Plutonium Modernization. The HE&E program includes the Energetic 

Materials Characterization project, the High Explosives (HE) Synthesis, Formulation, and Production 

project, and the HE Science and Engineering project. As with Plutonium Modernization, these line-item 

construction projects were captured under Infrastructure and Operations in previous years.

The budget request for the Primary Capability Modernization program increased to support:

◼ Activities associated with Los Alamos Plutonium Operations, LAP4, and SRPPF

◼ HE&E modernization through establishing HE production capability at the Naval Surface Warfare 

Center – Indian Head Division, preliminary design for the Energetic Materials Characterization 

project, and final design and start of construction for HE Synthesis, Formulation, and Production

5.5.2.2 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 three subprograms: (1) Uranium 

Modernization (formerly Uranium Sustainment), (2) Depleted Uranium Modernization, and (3) Lithium 

Modernization. The Lithium Processing Facility and Uranium Processing Facility projects are now captured 

within the Secondary Capability Modernization program instead of Infrastructure and Operations.

The overall decrease in the budget request for Secondary Capability Modernization reflects the transition 

from peak construction activities for the Uranium Processing Facility; however, the budget request for 

Depleted Uranium Modernization and Lithium Modernization increased to support:

◼ Re-establishing a reliable supply of High Purity Depleted Uranium metal and investing in key new 

technologies to modernize production and meet future demands, including modernizing the 

historical wrought process and investing in critical foundry modernization projects

◼ Fully funding minor construction projects supporting Lithium Modernization such as the Lithium 

Lab Area Upgrades, Backup Crusher/Grinder project, and the Lithium Process Equipment 

Relocation risk reduction activity

5.5.2.3 Tritium Modernization and Domestic Uranium Enrichment

Tritium Modernization and Domestic Uranium Enrichment (DUE) consist of two parts: (1) Tritium 

Modernization, which produces, recovers, and recycles tritium to support national security requirements,

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 Tritium Finishing Facility line-item project now resides 

within this program and no longer falls under Infrastructure and Operations.

The budget requests for Tritium Modernization and Domestic Uranium Enrichment increased to support:

◼ Increasing irradiation of tritium-producing burnable absorber rods (TPBAR) to meet multi-year 

plans for producing tritium, consistent with sustaining a reliable, flexible, and resilient supply 

chain to meet National Security requirements

◼ Licensing Tennessee Valley Authority reactors beyond 1,792 TPBARs and Spent Fuel Pool Rerack

◼ Replacing Hot and Cold Nitrogen and Thermal Cycling Absorption Process equipment at the 

Savannah River Site (SRS)
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◼ Completing final design activities and the Site Preparation and Warehouse subproject for the 

Tritium Finishing Facility project

◼ Down-blending highly enriched uranium (HEU) to extend future tritium need dates, which had 

previously been funded in a separate HEU down-blend line and is now included in the DUE line

◼ Increasing centrifuge development scope and maturity as the DUE program advances towards 

larger-scale R&D demonstrations

5.5.2.4 Non-Nuclear Capability Modernization

Non-Nuclear Capability Modernization consolidates management and oversight of strategic investments 

to modernize capabilities for design, qualification, and production of non-nuclear components for 

multiple weapon systems. This program provides increased capability and capacity to produce, and 

qualify, non-nuclear components to meet scheduled stockpile sustainment and weapon modernization 

programs. In addition, this program enables development of strategies, processes, and new capabilities 

and purchasing programmatic equipment for production of non-nuclear components. The Power Sources 

Capability line-item is now captured within this program instead of Infrastructure and Operations.

The budget request for this program increased to support:

◼ The transfer of scope for Accelerator and Major Environmental Test Facility programmatic 

equipment maintenance requirements from Infrastructure and Operations

◼ Additional support for required qualification and testing capabilities, including modernization 

efforts for the radiation testing facility Annular Core Research Reactor at Sandia National 

Laboratories (SNL)

◼ Tester Transformation Initiative aimed at improving tester requirements by establishing a means 

for pre-qualifying testers to a common design agency-production agency platform and ensuring

designs and hardware meet requirements

◼ Direct funding for At-Risk Materials, an enterprise-wide effort for early identification of at-risk 

materials and development of solutions to avoid supply chain interruptions

5.5.2.5 Capability 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 aging, broken, or 

outdated equipment and supporting systems. CBI activities primarily include 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 increased to support the expansion of the Flexible Production 

Capacity Initiative.

5.5.3 Key Milestones

DOE/NNSA must invest in re-establishing production capabilities and modernizing programmatic 

infrastructure to properly support the current and future nuclear deterrent mission. Although

programmatic construction projects shifted from Infrastructure and Operations to the relevant programs

in the FY 2023 budget request, in previous SSMPs, key infrastructure milestones were included in the 
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relevant program areas, so there is no significant change to the milestone sections because of this shift.

Key milestones for Production Modernization are presented by program in Sections 5.5.3.1–5.5.3.5.

5.5.3.1 Primary Capability Modernization

Key milestones for Primary Capability Modernization are in Figure 5–4. Major changes from last year’s 

plan related to Primary Capability Modernization are: 

◼ The FY 2022 milestone, Obtain Critical Decision (CD)--1 for Energetic Materials Characterization, 

is delayed to FY 2023 to align the project’s post-CD-1 activities with appropriated project funding 

available beginning in FY 2023.

◼ The FY 2032 to FY 2035 milestone, Achieve 80 pits per year (ppy) production capability as close to 

2030 as possible, is now shown as Obtain CD-4, Approve Start of Operations or Project Completion, 

for SRPPF to provide clarification that following the start of operations at SRPPF (CD-4 approval),

SRPPF will then ramp up to projected pit production capability.

◼ The FY 2026 milestone, Obtain CD-4 for High Explosives Science and Engineering, is delayed to 

FY 2027 due to a termination of the early works subcontractor, requirement to replan remaining 

scope, and a delay in awarding the main works construction contract.

◼ The FY 2028 milestone, Obtain CD-4 for Energetic Materials Characterization, is shifted to FY 2030 

due to a higher fidelity schedule estimate as a result of additional design and scheduling analysis 

required prior to CD-1, Approve Alternative Selection and Cost Range.

◼ The FY 2028 milestone, Obtain CD-4 for CMRR, is delayed to FY 2029 to prioritize LAP4 and major 

item of equipment projects within the Plutonium Facility.

One milestone from last year’s SSMP is no longer included as a milestone:

◼ Complete construction of the Energetics Manufacturing Science and Technology Project

Figure 5–4. Key milestones for Primary Capability Modernization
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5.5.3.2 Secondary Capability Modernization

Key milestones for Secondary Capability Modernization are in Figure 5–5. There were no substantive 

changes to the Secondary Capability Modernization milestones from last year’s SSMP.3 

One milestone from last year’s SSMP was completed in FY 2022:

◼ Qualify lithium small-scale purification, conversion, and reaction capabilities

One milestone from last year’s SSMP that was anticipated to be completed in FY 2022, “Perform 

production melts for binary ingot,” is now anticipated to be completed in FY 2023 due to unexpected, 

prolonged production Vacuum Arc Remelt (VAR) equipment restart activities. Current test and 

development needs are being met by using development binary ingots from the development VAR at the 

Test and Demonstration Facility. 

Figure 5–5. Key milestones for Secondary Capability Modernization

5.5.3.3 Tritium Modernization and Domestic Uranium Enrichment

Key milestones for Tritium Modernization and Domestic Uranium Enrichment are in Figure 5–6. Major 

changes from last year’s plan related to Tritium Modernization and Domestic Uranium Enrichment are:

◼ The FY 2023 milestone, Implement use of new TPBAR Transport Cask for four-fold increase in 

capacity, is shifted to FY 2025 due to the current TPBAR irradiation schedules, which allow existing 

capabilities to meet transportation requirements through FY 2025.

◼ The FY 2024 milestone, Obtain CD-2/3, Approve Performance Baseline/Approve Start of 

Construction, for Tritium Finishing Facility, is delayed to FY 2026 due to revised Savannah River 

Nuclear Solutions cost and projected schedule baselines to achieve CD-2/3.

◼ The FY 2024 milestone, Obtain CD-3A, Approve Long-Lead Item Procurements, for the Tritium 

Finishing Facility, is shifted to FY 2025 after completion of the design performance baseline.4

3 The original baseline date for the Uranium Processing Facility CD-4 approval of December 2025 is under review.

4 NNSA completed the design performance baseline after completion of the FY 2023 Construction Project Data Sheet.
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◼ The FY 2024 milestone, Complete facility modifications to prepare for future demonstration of the 

ORNL small centrifuge, changed to FY 2023 consistent with the FY 2023 President’s Budget 

Request for the completion of this Minor Construction project.

◼ The FY 2041 milestone, Obtain CD-4, Approve Start of Operations or Project Completion, for 

Domestic Uranium Enrichment Facility, has a completion range of FY 2041 to FY 2044 to 

accommodate potential uncertainty in future tritium production requirements.

There were no milestones in last year’s SSMP scheduled for completion in FY 2022.

Figure 5–6. Key milestones for Tritium Modernization and Domestic Uranium Enrichment

5.5.3.4 Non-Nuclear Capability Modernization

Key milestones for Non-Nuclear Capability Modernization are in Figure 5–7. One milestone in last year’s 

SSMP, Complete NNCC Long Term Plan, is no longer applicable and therefore not published in Figure 5–7.

Major changes from last year’s plan related to Non-Nuclear Capability Modernization are:

◼ The FY 2023 milestone, Complete SNL Agile Facility final fitout and transition to operations, is 

delayed to FY 2024 based on the construction contractor’s draft schedule of completion in the 

first quarter of 2024 vice the fourth quarter of 2023 due to delays in obtaining materials and 

potential difficulties with hiring laborers.

◼ The FY 2023 milestone, Finalize design and obtain CD-2/3 for Power Sources Capabilities, is 

delayed to FY 2024 to accommodate a conceptual re-design after the original conceptual design 

was deemed unaffordable.

◼ The FY 2025 milestone, Obtain KCNSC Short-Term Expansion Space, has been delayed to FY 2027 

to reflect the KCNSC Building 23 North completion timeline. KCNSC Short-Term Expansion Space 

is on schedule to complete buildout of the South end of Building 23 by FY 2026, and plans to 

additionally complete buildout of the North end of Building 23 by FY 2028.
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◼ The FY 2026 milestone, Obtain CD-4 Power Sources Capability, is delayed to FY 2029 due to earlier 

design milestone delays and expected construction schedule challenges due to availability of craft 

in the greater Albuquerque area.

◼ The FY 2022 milestone, Upgrade Annular Core Research Reactor Simulator, is shifted to FY 2024 

due to challenges with obtaining the necessary electronic components. 

Four milestones from last year’s SSMP were completed in FY 2022 or the first quarter of FY 2023: 

◼ Obtain CD-1 for Power Sources Capabilities

◼ Complete standup of Lawrence Livermore National Laboratory (LLNL) Polymer Enclave

◼ Complete Award of Construction for Agile Facility Build Out

Figure 5–7. Key milestones for Non-Nuclear Capability Modernization

5.5.3.5 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.

5.6 Stockpile Research, Technology, and Engineering

Stockpile Research, Technology, and Engineering (SRT&E) provides the knowledge and expertise needed 

to maintain confidence in the nuclear stockpile without additional nuclear explosive testing. SRT&E

encompasses six major subprograms: (1) Assessment Science, (2) Engineering and Integrated 

Assessments, (3) Inertial Confinement Fusion (ICF), (4) Advanced Simulation and Computing (ASC),

(5) Weapon Technology and Manufacturing Maturation, and (6) Academic Programs.

5.6.1 Budget

The budget request for SRT&E decreased 3.6 percent from the FY 2021 enacted budget (comparable 

structure) due to reductions in line-item construction project funding and is illustrated in Figure 5–8. 
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Figure 5–8. FY 2023 President’s Budget Request for Stockpile Research, Technology, and Engineering

5.6.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

5.6.2.1 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 U1a Complex (U1a) Enhancements 

Project line-item is also now captured within this program instead of Infrastructure and Operations.

The budget request for Assessment Science decreased, driven by reduced funding needs for U1a 

Enhancements that are partially offset by increases to support burn studies for boost science and analysis 

as well as ECSE procurements.

5.6.2.2 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 stockpile-to-target 

sequence is understood, ensuring a responsive nuclear deterrent through collaborative partnerships, 
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proactive integration, and assessments. This program includes seven subprograms: (1) Archiving and 

Support, (2) Delivery Environments, (3) Weapons Survivability (previously Nuclear 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 (CREST) 

line-item project now resides within this program instead of Infrastructure and Operations.

The budget request for Engineering and Integrated Assessments increased to support: 

◼ Conceptual design costs for CREST—the increased funding for CREST is partially offset by shifting 

resources from all Engineering and Integrated Assessments’ programs to support higher priority 

NNSA efforts.

◼ Studies and Assessments to support pre-Phase X/6.X studies, which focus on the conduct and 

management of refurbishment activities of existing weapons per the Phase 6.X guidelines, in 

addition to feasibility assessments of future nuclear weapon stockpile requirements.

5.6.2.3 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 to use available carryover while prioritizing support for maturing 

experimental platforms to execute HED experiments critical to supporting stockpile needs.

5.6.2.4 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 six 

subprograms: (1) Integrated Codes, (2) Physics and Engineering Models, (3) Verification and Validation,

(4) Advanced Technology Development and Mitigation, (5) Computational Systems and Software 

Environment, and (6) Facility Operations and User Support. The Exascale Computing Facility 

Modernization line-item project now falls within the ASC program instead of Infrastructure and 

Operations.

The overall decrease in the budget request for ASC is due to Exascale Computing Facility Modernization 

project completion, while funding for the rest of ASC increased slightly.

5.6.2.5 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.
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The budget request for Weapons Technology and Manufacturing Maturation decreased due to:

◼ The transfer of quality assurance scope and funding from Weapon Technology Development to 

the Stockpile Management/Production Operations

◼ The transfer of direct cast scope and funding from Advanced Manufacturing Development to the 

Secondary Capability Modernization program within the Office of Production Modernization

◼ The shift of resources from the three Weapon Technology and Manufacturing Maturation 

programs to support higher priority DOE/NNSA efforts

5.6.2.6 Academic Programs

Academic Programs support investments in science and engineering disciplines critically important to the 

nuclear security enterprise. Funding provided for the program’s grants, research centers of excellence, 

fellowships, and other activities offers individuals an introduction to the mission and people of the 

national laboratories and helps establish a workforce pipeline to strengthen the future enterprise. 

Academic Programs includes five subprograms: (1) Stewardship Science Academic Alliance, (2) Minority 

Serving Institution Partnership Program, (3) Joint Program in High Energy Density Laboratory Plasmas,

(4) Computational Science Graduate Fellowships, and (5) Predictive Science Academic Alliance Program.

The slight decrease in the budget request for Academic Programs reflects reprioritization of Stewardship 

Science Academic Alliance, while supporting existing awards until completion.

5.6.3 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 5–9. Major changes from last year’s plan are:

◼ The FY 2022 milestone, Accept ATS-3/Crossroads Phase 1 computing platform, is shifted to 

FY 2023 due to supply chain challenges, as well as application and software issues. 

◼ The FY 2023 milestone, Accept ATS-4/El Capitan exascale computing platform, is now correctly 

shown in FY 2024 and was previously published in error. 

◼ The FY 2023 milestone, Complete Advanced Sources and Detectors (ASD) accelerator injector 

testing at the integrated test stand, is delayed to FY 2026 due to COVID-19 and supply chain issues 

associated with delivery of materials. ASD was in the design phase during COVID-19, which caused 

delays as designers could not come to laboratories to work using CAD machines, and many parts 

ordered for prototyping were delayed due to vendor staffing.

◼ The FY 2025 milestone, Obtain CD-4 for ASD-Scorpius, is delayed to FY 2027 due to COVID-19 and 

supply chain issues associated with delivery of materials.

◼ The FY 2024 milestone, Execute Excalibur Experiment (ECSE reactivity), is delayed to FY 2025 due 

to an updated subcritical experiments (SCE) schedule.

◼ The FY 2025 milestone, Complete Red Sage & Nimble subcritical experiment campaigns, is delayed 

to FY 2026 due to an updated SCE schedule.

◼ The FY 2026 milestone, Execute Sherman Experiment (ECSE plutonium radiograph), is delayed to 

FY 2028 due to an updated SCE schedule.
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Three milestones from last year’s SSMP were completed in FY 2022:

◼ Complete construction of Exascale Computing Facility Modernization

◼ Obtain CD-2/3 for ASD-Scorpius

◼ Qualify and deploy a new scintillator for Confined Large Optical Scintillator Screen and Imaging 

System (CoLOSSIS) I and II

Figure 5–9. Key milestones for Stockpile Research, Technology, and Engineering

5.7 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. Capabilities Based Investments, previously 

under Recapitalization, now resides under Production Modernization, and programmatic construction 

projects have shifted to their relevant programs. Additional information about Infrastructure and 

Operations can be found in Chapter 4, “Infrastructure and Operations.”

5.7.1 Budget

The budget request for Infrastructure and Operations increased 3.5 percent from the FY 2021 enacted 

budget (comparable structure) and is illustrated in Figure 5–10.
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Figure 5–10. FY 2023 President’s Budget Request for Infrastructure and Operations

5.7.2 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

5.7.2.1 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:

◼ The Plutonium Modernization mission, including the production of at least 30 ppy at Los Alamos 

National Laboratory (LANL)

◼ Operations support personnel to complete 100 percent of SRS mission deliverables, including LEP 

requirements and gas transfer system surveillance requirements per schedule

◼ Increased safety basis needs at the Pantex Plant (Pantex)

Note: The increase is partially offset by a transfer of scope for programmatic equipment maintenance 

at SNL to the Production Operations program.
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5.7.2.2 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 a small adjustment 

to reduce uncosted balances. This is offset by an increase for additional support for the Material 

Managers at the sites under the Nuclear Materials Integration Program.

5.7.2.3 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 and 

facility-related equipment 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:

◼ The Plutonium Modernization mission, including the production of at least 30 ppy at LANL

◼ Increased maintenance needs at SNL to support the Microsystems Engineering, Science, and 

Applications Extended Life Program

◼ Transfer of the Waste Solidification Building at SRS from the Material Management and 

Minimization’s Material Disposition subprogram within Defense Nuclear Nonproliferation

Note: The increase is partially offset by a transfer of scope for programmatic equipment maintenance 

at KCNSC to the Production Operations program.

5.7.2.4 Recapitalization

Recapitalization modernizes DOE/NNSA’s infrastructure by prioritizing investments to improve the 

condition and extend the life of structures, capabilities, and systems, thereby improving the safety and 

quality of the workplace. Funding is used to address numerous obsolete support and safety systems,

revitalize facilities that are beyond the end of their design life, address climate adaptability and resilience,

and improve 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 decrease of the budget request for Recapitalization reflects a realignment to Mission Enabling 

Construction to address modernizing larger projects.

5.7.2.5 Line-Item Construction

Construction is critical in revitalizing the nuclear security enterprise. These 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 no longer 

falls under this subprogram, and instead was shifted to the respective programs.
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The budget request for Mission Enabling Construction includes funding in FY 2023 for:

◼ Design for the Electrical Power Capacity Upgrade at LANL

◼ Plutonium Modernization Operations and Waste Management Office Building at LANL

◼ Construction for the Special Materials Facility at the Y-12 National Security Campus (Y-12)

◼ The transition to construction for the Digital Infrastructure Capability Expansion project at LLNL

Additional information on planned line-item investments can be found in Chapter 4, “Infrastructure and 

Operations.”

5.7.3 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 4, 

Figures 4–5 through 4–12. 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 (AoA) 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. 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.

5.7.4 Infrastructure Maintenance and Recapitalization Investments

As part of the IMI, DOE/NNSA is using BUILDER, a system developed by the 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, life cycle, 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. As shown in Table 5–2, 

DOE/NNSA’s new calculated RPV is $124.9 billion based on end-of-year data. The DM backlog is tied to 

RPV as it costs more to repair a more expensive facility, therefore, as expected, DM increased with the 

deployment of DOE/NNSA’s new, more accurate, data-driven approach from $5.8 billion as of FY 2020 to 

$6.1 billion as of FY 2021. The overall physical condition of DOE/NNSA’s infrastructure did not decline.

Table 5–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant Value

Metric FY 2019 FY 2020 FY 2021

RN $8.9B $9.4B $9.8B

DM $4.8B $5.8B $6.1B

RPV $124.3B $116.3B $124.9B

RN/RPV Ratio 7.16% 8.08% 7.88%

DM/RPV Ratio 3.85% 4.99% 4.90%

RN = repair needs

DM = deferred maintenance

RPV = replacement plant value
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In response to GAO recommendations, this information is provided to improve transparency in the 

budget. Table 5–3 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. DOE/NNSA has decreased recapitalization investments by $25 million from 

FY 2022 to FY 2023 to support additional construction of larger facilities. Recapitalization continues to 

include deactivation and demolition of excess, and underused, facilities to reduce DOE/NNSA’s footprint. 

Maintenance investments reflect a decreased funding level from FY 2022 to FY 2023 due to the 

unanticipated increase above the request level in FY 2022. Overall 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 5–3. Projected FY 2023 DOE/NNSA infrastructure maintenance and 

recapitalization investments5

FY 2021 FY 2022 FY 2023

Replacement Plant Value (RPV) ($B) 116.3 124.9 125.9

Maintenance 

Benchmark 

2–4% RPV

Infrastructure and Safety Maintenance Investments ($K) 667,000 700,000 680,000

Other NNSA Maintenance Investments (direct and indirect funded) ($K) 286,397 284,090 284,434

Total NNSA Maintenance Investments ($K) 953.397 984,090 964,434

Maintenance as % RPV 0.76% 0.78% 0.76%

Recapitalization 

Benchmark 

1%

Infrastructure and Safety Recapitalization Investments ($K) 573,717 600,000 561,663

Other NNSA Recapitalization Investments ($K) 331,979 393,716 407,393

Total NNSA Recapitalization Investments ($K) 905,696 993,716 969.056

Recapitalization as % RPV 0.73% 0.79% 0.76%

$B = billion dollars

$K = thousand dollars

5.8 Other Weapons Activities

5.8.1 Budget

The funding schedule for Other Weapons Activities is illustrated in Figure 5–11.

5 These values do not include Naval Reactors investments.
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Figure 5–11. FY 2023 President’s Budget Request for Other Weapons Activities

5.8.2 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.

5.8.2.1 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

The budget request for Secure Transportation Asset decreased 1.2 percent from FY 2021. 

The overall budget request for Operations and Equipment decreased due to the completion of aircraft 

procurement in FY 2021, however, an increase is requested for the Mobile Guardian Transporter (MGT) 

subprogram to support its schedule deliverables including:

◼ Continued development of Engineering Releases

◼ Continued Pre-Production Unit stage builds

◼ Validation of the Pre-Production Unit manufacturing process

◼ Test Article 2 Crash Test

The budget request for Program Direction increased to support the transfer of support service contract 

costs from Operations and Equipment to Program Direction.

5.8.2.2 Key Milestones

Aging transportation assets must be replaced to meet, and maintain, convoy safety and security 

requirements. The STA milestones in Figure 5–12 will enable DOE/NNSA to support evolving 

transportation requirements for the current and future stockpile. 
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Changes from last year’s plan are:

◼ The FY 2037 milestone, Complete MGT production, is delayed to FY 2038 due to supply chain 

disruptions stemming from the COVID-19 pandemic; disruptions to materials and piece parts, and 

a loss of critical skills in the vendor bases are impacting deliverables. Custom electronic (printed 

wiring boards/printed wiring assembly) fabrication needed to support MGT has been especially 

impacted. This is a persistent issue, however, the MGT team is working to minimize future delays 

by looking at advanced purchases of materials needed for production to account for the extended 

delivery timeline.

One milestone from last year’s SSMP, Design and begin production of the next generation armored tractor 

and escort vehicle, was anticipated to be completed in FY 2022 but was not completed. This milestone is 

now split into two separate milestones, Design and begin production of the next generation armored 

tractor and Design and begin production of the next generation escort vehicle.

◼ Design and begin production of the next generation armored tractor is delayed to 2025 due to 

inadequate vendor response. The program is evaluating the contracting vehicle and will continue 

pursuing this project.

◼ Design and begin production of the next generation escort vehicle is delayed to FY 2023.

Prototypes are currently being evaluated, and final design review and production are anticipated 

to commence by the end of FY 2023.

Figure 5–12. Key milestones for Secure Transportation Asset

5.8.3 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 

security incidents to acts of terrorism. The West End Protected Area Reduction (WEPAR) line-item project 

is also included within DNS.

5.8.3.1 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

The budget request for DNS increased 11.8 percent from FY 2021 to FY 2023. 

The budget request for DNS increased to support: 

◼ Refined security requirements associated with growth across the nuclear security enterprise, 

including plutonium pit production and the Uranium Processing Facility

◼ Increased security requirements related to design-basis threat implementation and sustaining 

core security requirements
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◼ Caerus, the highest priority Security Infrastructure Revitalization Program (SIRP) projects, and the

highest priority initiatives for the Physical Security Center of Excellence and the Center for Security 

Technology, Analysis, Response, and Testing (CSTART)

Funding for the WEPAR line-item project decreased as construction moves toward completion.

5.8.3.2 Key Milestones

The SIRP 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 5–13 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. Changes from last year’s plan are:

◼ The FY 2024 milestone, Complete Y-12 WEPAR, PIDAS modernization, and entry control facility 

upgrade, is shifted to FY 2025 to correct a mistake in the FY 2022 SSMP and align with the CD-4

date, as outlined in the approved CD-2/3 package.

◼ The FY 2026 milestone, Complete Caerus cutover, is delayed to FY 2027 due to the initial rollout 

delay, caused by supply chain issues.

◼ The FY 2029 milestone, Complete Pantex Perimeter Intrusion Detection and Assessment System 

(PIDAS) physical security system components and infrastructure refresh for Zone 4, is delayed to 

FY 2030 due to a reprioritization of SIRP projects.

◼ The FY 2030 milestone, Complete SRS SRPPF PIDAS, is shifted to FY 2029 to reflect the CD-4 date 

for the SRS SRPPF PIDAS project. The training and certification of all forces and systems for the 

SRS SRPPF PIDAS will be complete in FY 2031. This milestone previously read Complete SRS PIDAS

and has been updated for clarity. 6

Figure 5–13. Key milestones for Defense Nuclear Security

6 The SRS SRPPF PIDAS is funded through the SRPPF Safeguards and Security Subproject, which has a CD-2/3 date of FY 2024 and 

a CD-4 date of FY 2029. Since the PIDAS is a major milestone within that subproject, it is called out separately in this graphic.
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5.8.4 Information Technology and Cybersecurity

The DOE/NNSA Office of the Associate Administrator for Information Management and Chief Information 

Officer (OCIO) supports IT and cybersecurity services and solutions, which include continuous monitoring, 

cloud-based technologies, and enterprise security technologies to help meet security challenges. The 

DOE/NNSA OCIO must provide a set of capabilities that enable the mission to increase organizational 

efficiency, protect information assets, enhance communication with internal and external partners, 

ensure continuous monitoring, and support effective incident response. DOE/NNSA OCIO executes a 

strong cybersecurity program that funds ongoing operations and invests in improvements across the 

nuclear security enterprise to meet the President’s Executive Order 14028 to improve the nation’s 

cybersecurity.

5.8.4.1 FY 2023 Budget Request Compared to FY 2021 Enacted Budget

The budget request for Information Technology and Cybersecurity increased 21.7 percent from FY 2021. 

The FY 2023 budget request includes funding for the operation and modernization of the Emergency 

Communications Network previously funded under Emergency Operations within Defense Nuclear 

Nonproliferation.

The budget request for IT and Cybersecurity increased to support:

◼ Investments in cybersecurity tools and services provided to the enterprise

◼ Technology modernization investments for critical classified and unclassified systems

5.8.4.2 Key Milestones

The milestones in Figure 5–14 are necessary steps toward achieving a modernized IT infrastructure and 

cybersecurity posture for the nuclear security enterprise. Several milestones with ongoing activities from 

last year’s SSMP anticipated for completion in FY 2022 have been reworked and are not published again 

in Figure 5–14:

◼ Implement Phase II of DOE/NNSA’s IT Modernization Plan

◼ Begin architecture development of the classified wireless network for non-pit production facilities

◼ Deploy KCNSC hybrid cloud platform in support of Joint Technology Demonstrator project

◼ Perform cybersecurity program budget re-baseline site assessments

◼ Develop phase II system architecture for modernizing the Enterprise Secure Computing 

environment

◼ Implement special network access

◼ Implement the DOE/NNSA Application Modernization Strategy

◼ Implement a Telecommunications Security Program within DOE/NNSA

◼ Complete the modernization of the Information Assurance Response Center cybersecurity 

infrastructure

◼ An additional milestone that was not published in last year’s SSMP was completed in FY 2022:

◼ Complete the external Institute for Defense Analyses cybersecurity assessment
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Figure 5–14. Key milestones for Information Technology and Cybersecurity

5.8.5 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 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. 

5.9 Budget Projections Beyond FY 2027

This section explains the cost estimation methodology that DOE/NNSA uses to create long-term budget 

projections. These projections are used to evaluate, over a longer timeframe than considered in the 

FYNSP and during programming activities, the total required resources to accomplish the program of 

record, how those resources are allocated, and the overall affordability of the program (see Section 5.10).

5.9.1 Basis for Budget Projections

For most of Weapons Activities, the FY 2023–FY 2027 budget request was generated as part of the 

DOE/NNSA planning and 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 requests for Stockpile Major 

Modernization programs are informed by the processes described in Section 5.9.2. The budget estimates 

for FY 2028 and beyond reflect the costs of continuing the FYNSP program described in this SSMP, while 

sustaining, and enhancing, the Weapons Activities capabilities that are essential to executing the stockpile 

mission.

The budget projections beyond the FYNSP are based on requirements and will vary, depending on the 

individual program or subprogram. Some portions 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. 

Some portions of the program, primarily Stockpile Major Modernization programs and major 

programmatic construction projects, will not proceed at the same level of effort from FY 2028 through 

FY 2047. The estimates and the basis for each of these elements of the Weapons Activities portfolio are 

described in Sections 5.9.2–5.10.

7 Projection of budget estimates for these efforts in this way assumes the continued manageability of whatever risks are present 

during the FYNSP at the same level of effort over the FYNSP period, as is typically represented by the funding level of the last year 

of the FYNSP.
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5.9.2 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 next sections summarize cost estimates for Stockpile Major Modernization programs within the 

current 25-year period. The basis for the cost estimates varies from those using top-down cost models 

(such as analogy comparisons to past work completed, parametric relationships, and subject matter 

expert judgment) to those using bottom-up models (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.

Reflecting decisions made during the 2022 Nuclear Posture Review, no funding is requested for the W80-4 

Alteration Sea-launched Cruise Missile-Nuclear (SLCM-N) program in the FY 2023 budget request. The 

program, following direction in the Nuclear Posture Review, has been removed from this section.

5.9.2.1 Cost Estimates across the Phase X/6.X Process

Figure 5–15 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 5–15. Cost estimates across the Phase 6.X Process

The DOE/NNSA Office of Management and Budget, 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, early programming, and budget deliberations. These

planning estimates for Stockpile Major Modernization are:

◼ Based on a defined scope and cost uncertainty at the time and updated annually for the SSMP8

8 Planning estimates assume scopes that are in line with current policy objectives (such as a commitment to surety upgrades) for 

the modernization effort. 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.
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◼ Inclusive of 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

◼ Unconstrained by future budget availability, which may differ from future budget requests 

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 5.9.2.2.

The WDCR is developed by the program teams responsible for the warhead modernization programs and 

provides cost estimates for design, qualification, production, and life cycle 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 late 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, and 6.5, First 

Production.

5.9.2.2 DOE/NNSA Office of Management and Budget Cost Estimating Methodology

The DOE/NNSA’s 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 of the W76-1, B61-12, 

W88 Alt 370, W80-4, and production of the W76-1, B61-12 and W88 Alt 370) and the evaluation 

of the relative complexities of future systems11

9

In estimating the cost of a warhead modernization program, the weapon programs depend on an adequately funded base of 

other DOE/NNSA capabilities, as well as activities that 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 and coordinated with other programs to ensure funding is available to support the modernization program

10 Additional detail on the cost estimating methodology of DOE/NNSA’s Office of Management and Budget planning estimates 

can be found 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 between the complete W76-1 and nearcomplete B61-12 LEP and W88 Alt 370 Program 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 site 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 were 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.

5.9.2.3 Current Estimates

Figures 5–16 through 5–20 and Tables 5–4 through 5–12 provide cost estimates for each Stockpile Major 

Modernization program for the 25-year SSMP timeframe. Table 5–4 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 5.9.2.4 through 5.9.2.10. 

Table 5–4. DOE/NNSA cost estimates for Stockpile Major Modernization Programs13

Stockpile Major Modernization 

Program Type of Cost Estimate

Total Estimated Cost 

(FY 2022 dollars in billions)

Total Estimated Cost

(then-year dollars in billions)

B61-12 LEP BCR/SAR 9.6 8.3

W88 Alteration Program BCR/SAR 3.0 2.8

W80-4 LEP WDCR/SAR 10.4 11

W87-1 Modification Program14 Planning Estimate 10.4 12.5

W93 Program Planning Estimate 14.1 19.8

Future Strategic Land-Based Warhead Planning Estimate 13.3 20.2

Future Strategic Sea-Based Warhead Planning Estimate 17.8 27.9

Future Air-Delivered Weapon Planning Estimate 11.2 20.3

BCR= Baseline Cost Report

LEP = life extension program

SAR = Selected Acquisition Report

WDCR = Weapon Design and Cost Report

12 See Lee, David. The Cost Analyst’s Companion, 3rd ed., McLean, VA: Logistics Management Institute, McLean, VA.

13 SAR and WDCR values are provided when available. For programs that only have a planning estimate, the proposed budget is 

provided; for programs pre-phase 1/6.1 the p90 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. Due to the 

differing types of cost estimates, the accuracy of these total program cost estimates varies.

14 The total estimated costs for the W87-1 Modification program represent the midpoint between the p50 and p85 values.
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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 and DoD, in constant FY 2022 and 

then-year dollars. Where appropriate, the tables also include pre-SAR values for pre-Phase 6.2 costs.15

The low estimates presented in the tables and graphs as the green line represent the mid-point (p50) of 

the cost estimate. The high estimates continue to represent the 85th percent (p85) for the B61-12, W88 

Alt 370, W80-4, W87-1, and W93; the estimate increased to the 90th percent (p90) for the future systems 

to reflect the greater uncertainty.

For early-stage programs using planning estimates (such as the W87-1 Modification Program), the figures 

and tables reflect the proposed FY 2023 FYNSP budget and, for years beyond FY 2023, the midpoint 

between the high and low estimates. 

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 2023 

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 an escalation rate of 3.0 percent. This 3.0 percent rate represents an average of 

the individual site escalation rates as documented in current WDCR/BCR estimates. 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.

5.9.2.4 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. Additionally, all commercial off-the-shelf Base Metal 

Electrode capacitor components that experienced an issue in late 2019 have completed first production 

unit and are at or are ramping to full-rate production. The values for development and production costs 

in Figure 5–16 and Table 5–5 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.

15 DoD amounts reflect the costs for weapon components for which DoD is responsible, such as arming and fuzing. While not 

budgeted or executed by DOE/NNSA, these costs reflect the program’s best approximation and are published for transparency 

to better reflect anticipated all-in costs. The total estimated cost is provided because warhead modernization program profiles 

often have later portions that extend beyond the published 25-year SSMP timeframe.
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Figure 5–16. B61-12 Life Extension Program cost from FY 2009 to completion16

Table 5–5. Total estimated cost for B61-12 Life Extension Program

FY 2012–FY 2027

Dollars in Billions

DOE/NNSA DoD17

FY 2022 Dollars Then-Year Dollars FY 2022 Dollars Then-Year Dollars

Pre-SAR Cost 0.5 0.4 N/A N/A

SAR Total 8.9 8.3 N/A N/A

SAR OPM Total 0.8 0.6 N/A N/A

Planning Estimate (High)a 10.0 9.4 0.2 0.2

Planning Estimate (Low)

a 9.4 8.8 0.2 0.2

OPM = Other Program Money

SAR = Selected Acquisition Report

a

Including OPM

5.9.2.5 W88 Alt 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 accepted the 

W88 Alt 370 into the stockpile in December 2021 and authorized Phase 6.6 entry in 2022. 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 (Other Program Money) remain unchanged at $171 million. 

The numbers in Figure 5–17 and Table 5–6 reflect the BCR update.

16 The value for FY 2012 has been updated from previous SSMPs to represent the appropriate SAR value for that year. The SAR 

value represents money spent after Phase 6.3 approval in July 2012. 

17 The DoD costs in this table represent funds provided by DoD for work by DOE/NNSA on specific components, per cost sharing 

agreements between DoD and DOE/NNSA, and does not include work done exclusively by DoD, such as the B61-12 tail kits.
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Figure 5–17. W88 Alteration 370 Program (with conventional high explosive refresh)

from FY 2013 to completion

Table 5–6. Total estimated cost for W88 Alteration 370 Program 

(with conventional high explosive refresh)

FY 2013–FY 2027

Dollars in Billions

DOE/NNSA DoD

FY 2022 Dollars Then-Year Dollars FY 2022 Dollars Then-Year Dollars

Pre-SAR Cost 0.1 0.1 N/A N/A

SAR Total 3.0 2.8 N/A N/A

SAR OPM Total 0.2 0.2 N/A N/A

Planning Estimate (High)a 3.2 3.1 1.0 1.0

Planning Estimate (Low)a 3.1 2.9 1.0 0.9

OPM = Other Program Money

SAR = Selected Acquisition Report

a

Including OPM

5.9.2.6 W80-4 Life Extension Program Cost Estimate

In FY 2019, the W80-4 LEP completed its WDCR and entered Phase 6.3 in which the design will continue 

to be refined. Prior to entry into Phase 6.4 in FY 2023, the W80-4 program will publish its BCR, an update 

to the WDCR. The W80-4 LEP is on track to support fielding the Air Force’sscheduled Long Range Standoff 

cruise missile initial and final operational capability dates. The current cost estimate is displayed in 

Figure 5–18 and Table 5–7. 
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Figure 5–18. W80-4 Life Extension Program cost from FY 2015 to completion

Table 5–7. Total estimated cost for W80-4 Life Extension Program

FY 2015–FY 2032

Dollars in Billions

DOE/NNSA DoD

FY 2022 Dollars Then-Year Dollars FY 2022 Dollars Then-Year Dollars

SAR Total 10.4 11.0 N/A N/A

SAR OPM Total 0.2 0.2 N/A N/A

Planning Estimate (High)a 11.8 12.8 0.2 0.2

Planning Estimate (Low)

a 10.3 11.1 0.1 0.1

OPM = Other Program Money

SAR = Selected Acquisition Report

a

Including OPM

5.9.2.7 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, previously referred 

to by the generic name of Ground Based Strategic Deterrent, 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 Modification Program. DOE/NNSA 

continues to evaluate other component design options and trades. In FY 2021, the W87-1 Modification 

Program completed Phase 6.2 and entered Phase 6.2A. The cost estimate in Figure 5–19 represents the 

latest projected program cost reflecting downselect and trade studies completed in Phase 6.2, and the 

FYNSP is informed by the ongoing WDCR. The estimates in Figure 5–19 and Table 5–8 do not include costs 
Department of Energy/National Nuclear Security Administration | April 2023

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associated with the production of plutonium pits for the W87-1 Modification Program. Those costs are 

contained in Plutonium Modernization.

Figure 5–19. W87-1 Modification Program cost from FY 2019 to completion18

Table 5–8. Total estimated cost for W87-1 Modification Program

5.9.2.8 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 5–9) is based on preliminary assumptions for one of the W93 designs, Option 2A, and provides a 

planning estimate only. The midpoint of the estimates (average of p50 and p85) 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.

18 Since the W87-1 Modification Program is using a planning estimate, the red and green lines represent the high and low 

estimates based on funding models from historical data. The blue bars in this figure show the program’s proposed FY 2023 FYNSP 

budget and, for years beyond FY 2023, the midpoint between the high and low estimates from the funding models.

FY 2019–FY 2037

Dollars in Billions

DOE/NNSA DoD

FY 2022

Dollars

Then-Year 

Dollars

FY 2022

Dollars

Then-Year 

Dollars

Planning Estimate (High)a 10.6 12.6 0.4 0.5

Planning Estimate (Low)

a 9.3 11.1 0.3 0.4

Proposed Budget 10.4 12.5 N/A N/A

a

Including Other Program Money
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Table 5–9. Total estimated cost for W93 Program (Option 2A)

Dollars in Billions

DOE/NNSA DoD

FY 2022

Dollars

Then-Year 

Dollars

FY 2022

Dollars

Then-Year 

Dollars

Planning Estimate (High) a 15.1 21.2 1.3 1.8

Planning Estimate (Low) a 13.1 18.5 1.0 1.4

Proposed Budget 14.1 19.8 N/A N/A

a

Including Other Program Money

5.9.2.9 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, and aging concerns, in 

candidate stockpile warheads. 

The Future Strategic Missile Warhead cost estimates(see Table 5–10, Table 5–11, and Table 5–12) provide

a planning estimate for notional systems based on an existing stockpile weapon scope with increased

uncertainty in design scope and quantities, adjusted for out-year escalation. These estimates will change 

as requirements and schedules are refined and will be updated in future versions of the SSMP.

Table 5–10. Total estimated cost for Future Strategic Missile – Land-Based Warhead (FSLW)

Dollars in Billions

DOE/NNSA DoD

FY 2022

Dollars

Then-Year 

Dollars

FY 2022

Dollars

Then-Year 

Dollars

Planning Estimate (High) a 14.5 22.6 0.4 0.6

Planning Estimate (Low) a 11.9 18.6 0.3 0.5

Proposed Budget 13.3 20.6 N/A N/A

a

Including Other Program Money

Table 5–11. Total estimated cost for Future Strategic Missile – Sea-Based Warhead

Dollars in Billions

DOE/NNSA DoD

FY 2022

Dollars

Then-Year 

Dollars

FY 2022

Dollars

Then-Year 

Dollars

Planning Estimate (High) a 19.6 31.5 1.3 2.0

Planning Estimate (Low) a 15.8 25.2 1.0 1.6

Proposed Budget 17.7 28.4 N/A N/A

a

Including Other Program Money

Table 5–12. Total estimated cost for Future Air-Delivered Weapon

Dollars in Billions

DOE/NNSA DoD

FY 2022

Dollars

Then-Year 

Dollars

FY 2022

Dollars

Then-Year 

Dollars

Planning Estimate (High) a 12.0 21.9 0.2 0.4

Planning Estimate (Low) a 10.3 18.8 0.1 0.3

Proposed Budget 11.2 20.3 N/A N/A

a

Including Other Program Money
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5.9.2.10 Summary of Cost Estimates

Figure 5–20 represents a summary of cost estimate ranges for all presently known warhead 

modernization programs from FY 2022 through FY 2047 based on schedule assumptions that are subject 

to change. The differences in the values from the FY 2022 SSMP reflect increases in new estimates for the 

W93, and in turn the estimates for other future systems that are based off the W93, as well as a later start 

for the development of the future systems which shifted the cost profile to the right. This chart also 

includes a wedge for a warhead modernization program starting in the early 2040s.

Figure 5–20. Total projected Stockpile Major Modernization costs for

FY 2022–FY 2047 with high and low estimates (then-year dollars)
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5.9.3 Construction

5.9.3.1 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 office19

◼ 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 

AoAs. 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 system20 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.

21 Table 5–13 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.

19 The DOE/NNSA Office of Management and Budget, Office of Programing, Analysis and Evaluation, performs the cost estimates 

on behalf of Defense Programs.

20 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.

21 DOE Guide 413.3-21A, Cost Estimating Guide.
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Table 5–13. 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

5.9.3.2 FY 2023 through FY 2047 Estimates

The budget request for capital acquisitions in FY 2023 reflects the latest estimates for existing 

construction projects. DOE/NNSA continues to execute the schedules of multiple ongoing major capital 

acquisition projects, such as the Uranium Processing Facility and U1a Complex Enhancements 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. The schedule for the highest-priority project proposals is shown by major capital acquisition 

projects and project proposals listed in Chapter 4, “Infrastructure and Operations.” This planning 

schedule will be updated annually. Changes will be made based on available funding and programmatic 

priorities.

The current program of record and the vetted programmatic construction project proposals included in 

Figures 4–5 through 4–11 are the basis for the aggregated cost estimates shown in Table 5–14.

22

 

Table 5–14 lists low and high estimates in then-year dollars for planned and proposed programmatic

capital acquisition projects from FY 2023 through FY 2047. 

Table 5–14. Weapons Activities capital acquisition estimated costs, FY 2023–FY 2047

Then-Year Dollars, in Billions Low a High b

Weapons Activities capital acquisition estimated costs 70.2 82.2

a The “Low” estimate reflects the base capital acquisition estimate captured in Figure 5–22. The low value is 

programmatically informed and represents the 70th percentile for the planned and proposed major construction 

projects listed in Section 4.3.1. 

b The “High” estimate represents the 85th percentile for the planned and proposed major construction projects listed in 

Section 4.3.1.

22 At this time, only programmatic construction cost estimates are included in the values shown in Table 5–14. It does not include 

mission enabling construction projects.
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The difference in the estimates as compared to the FY 2022 SSMP are a result of further analysis and 

higher fidelity estimates on major construction projects, including Domestic Uranium Enrichment and 

Depleted Uranium Manufacturing Capabilities.

5.10 Affordability

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 must 

make concerted investments now to make available the necessary capabilities and infrastructure to 

execute modernization programs to meet DoD timelines. If adjustments need to be made in future years, 

DOE/NNSA will work with DoD to consider and adjust schedule and/or scope to major activities, including 

potential effects to warhead modernization programs and infrastructure projects.

DOE/NNSA needs are subject to a high level of uncertainty due to the unique requirements inherent in 

the work that must be completed to meet objectives. Limited numbers of completed projects with similar 

complexity and scope, low quantities, stringent specifications, and multi-year development schedules add 

to the high level of uncertainty in early estimates. For these reasons, the projected costs beyond FY 2023 

incorporate some amount of uncertainty in the out-year weapons modernization and construction 

resource needs. These later plans and estimates are compared to external straight-line budget 

projections that have not been adjusted to be more predictive based on actual scope and schedule. 

Variances are managed as the out-years estimates move into the FYNSP window and as scope and 

schedule are further refined.

Budget projections for the out-years incorporate the Stockpile Major Modernization program cost 

estimates described in Section 5.9.2 and the cost estimates for the planned major programmatic 

construction projects described in Chapter 4, Section 4.2.1. Significant out-year projects include:

◼ Reestablishing a plutonium pit production capability 

◼ Reestablishing a Domestic Uranium Enrichment capability

◼ Revitalizing depleted uranium manufacturing capability

◼ Modernizing DOE/NNSA’s SRT&E capabilities for certifying warheads upon entry into the stockpile

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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 6-1

Chapter 6

Conclusion

This Department of Energy’s National Nuclear Security Administration’s (DOE/NNSA) Fiscal Year 2023

Stockpile Stewardship and Management Plan – Biennial Plan Summary (SSMP), together with its classified 

annex, is a key planning document for the nuclear security enterprise. This SSMP is the culmination of 

planning and programming 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 fiscal year (FY) 2023 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 through the Nuclear Weapons 

Council. 

In large part due to the current global security environment, DOE/NNSA executed its largest program in 

its 21-year history, advancing the Nation’s nuclear security mission through innovative science and 

technology solutions. These efforts are critical to ensuring the U.S. strategic deterrent remains safe, 

secure, and effective, and that the deterrence commitments extended to U.S. allies remains strong and 

credible.

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Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page A-1

Appendix A

Requirements Mapping

A.1 National Nuclear Security Administration Response to 

Statutory Reporting Requirements and Related Requests

The Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary

(FY 2023 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 fiscal year (FY) 2023 SSMP. 

A.2 50 U.S. Code § 2523

50 U.S. Code § 2523 FY 2022 Response FY 2023 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

All Chapters

(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). 

N/A Unclassified

All Chapters

(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). 

Unclassified

All Chapters

N/A

(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.

N/A Unclassified

Chapter 1,

Section 1.3, 

Figure 1-1

(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.

N/A Unclassified

Chapter 1,

Section 1.4;

Chapter 2,

Section 2.2,

Figure 2-2
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(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.

N/A Unclassified

Chapter 2, 

Sections 2.1, 2.2

(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.

N/A Unclassified

Chapter 4, 

Sections 4.2, 4.3;

Appendix C,

Section C-1

(5) A summary of the status, plans, and budgets for carrying out the stockpile 

responsiveness program under section 2538b of this title.

N/A Unclassified

Chapter 2, 

Section 2.1;

Chapter 5,

Section 5.4

(6) A summary of the plan regarding the research and development, 

deployment, and lifecycle sustainment of technologies described in subsection 

(d) (7).

N/A Unclassified

Chapter 1,

Sections 1.4, 1.5,

Figure 1-3

(7) A summary of the assessment under subsection (d)(8) regarding the 

execution of programs with current and projected budgets and any associated 

risks.

N/A Unclassified

Chapter 5,

Sections 5.1, 5.5, 

5.6, 5.9

(8) 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 5, 

Section 5.4

(9) Such other information as the Administrator considers appropriate. N/A

(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;

Unclassified

Chapter 1, 

Section 1.4; 

Chapter 2, 

Sections 2.1, 2.2

N/A

(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;

Unclassified

Chapter 8, 

Section 8.4, 8.9

N/A

(C) the status, plans, budgets, and schedules for warhead life extension 

programs and any other programs to modify, update, or replace warhead 

types;

Unclassified

Chapter 2, 

Sections 2.2, 2.4; 

Chapter 8, 

Section 8.4

N/A

(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;

Unclassified

Chapter 2, 

Section 2.1; 

Chapter 3, 

Section 3.5; 

Chapter 4, 

Section 4.3

N/A
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(E) a description of the process used in recertifying the safety, security, and 

reliability of each warhead type in the nuclear weapons stockpile;

Unclassified

Chapter 2, 

Section 2.1; 

Chapter 4, 

Sections 4.2.2, 4.3

N/A

(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);

Unclassified

Chapter 2, 

Section 2.1; 

Chapter 3, 

Sections 3.3.2, 

3.4.2; Chapter 4, 

Sections 4.2, 4.3

N/A

(G) mechanisms to provide for the manufacture, maintenance, and 

modernization of each warhead type in the nuclear weapons stockpile, as 

needed;

Unclassified

Chapter 2, 

Sections 2.1, 2.2, 

2.4; Chapter 3, 

Sections 3.2-3.5; 

Chapter 4, 

Section 4.3

N/A

(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;

Unclassified

Chapter 2, 

Sections 2.1.1, 2.4; 

Chapter 3, 

Section 3.5; 

Chapter 4, 

Section 4.3

N/A

(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;

Unclassified

Chapter 1, 

Section 1.3; 

Chapter 4, 

Section 4.2.2; 

Chapter 7 ; 

Appendix E

N/A

(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;

Unclassified

Chapter 2, 

Section 2.1.2

N/A

(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

Unclassified

Chapter 8, 

Sections 8.3-8.6, 

8.9

N/A

(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;

Unclassified

Chapter 8, 

Section 8.3

N/A

(M) the status, plans, activities, budgets, and schedules for carrying out the 

stockpile responsiveness program under section 2538b of this title; 

Unclassified

Chapter 4, 

Section 4.3; 

Chapter 8, 

Section 8.4–8.6; 

Appendix D

N/A

(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

Unclassified

Chapter 8, 

Section 8.4–8.6; 

Appendix D

N/A
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(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;

Unclassified

Chapter 2, 

Section 2.1; 

Chapter 4, 

Sections 4.2.2, 4.3;

N/A

(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

Unclassified

Chapter 4, 

Section 4.3

N/A

(C) the criteria developed under section 2522(a) of this title (including any 

updates to such criteria).

N/A N/A

(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;

Unclassified

Chapter 4, 

Sections 4.2, 4.3

N/A

(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;

Unclassified

Chapter 2, 

Section 2.1.2; 

Chapter 4,

Section 4.3; 

Appendix E

N/A

(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

Unclassified

Chapter 2, 

Section 2.1.2; 

Chapter 4, 

Section 4.2; 

Appendix E

N/A

(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—

Unclassified

Chapter 7, 

Sections 7.1, 7.3; 

Appendix E

N/A

(i) the number of scientists, engineers, and technicians, by discipline, 

required to maintain such competencies; and

Unclassified

Chapter 7, 

Sections 7.2, 7.3; 

Appendix E

N/A

(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.

Unclassified

Chapter 7, 

Section 7.4;

Appendix E

N/A

(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—

Unclassified

Chapter 6, 

Sections 6.3, 6.4

N/A
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(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; 

Unclassified

Chapter 6, 

Sections 6.3, 6.4

N/A

(ii) the most recent quadrennial defense review if such strategy has 

not been submitted as of the date of the plan; and

Unclassified

Chapter 6, 

Sections 6.3, 6.4

N/A

(iii) the most recent Nuclear Posture Review as of the date of the plan; Unclassified

Chapter 6, 

Sections 6.3, 6.4

N/A

(B) a schedule for implementing the measures described under 

subparagraph (A) during the 10-year period following the date of the plan; 

Unclassified

Chapter 6, 

Sections 6.3.1, 

6.3.2

N/A

(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

Unclassified

Chapter 8, 

Sections 8.7.1, 

8.9.3

N/A

(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.

Unclassified

Chapter 8, 

Section 8.7.4

N/A

(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;

Unclassified

Chapter 4, 

Section 4.4

N/A

(B) a description of the level of test readiness that the Administrator, in 

consultation with the Secretary of Defense, determines to be appropriate;

Unclassified

Chapter 4, 

Section 4.4

N/A

(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;

Unclassified

Chapter 4, 

Section 4.4

N/A

(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

Unclassified

Chapter 4, 

Section 4.4

N/A

(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).

Unclassified

Chapter 4, 

Section 4.4

N/A
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(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.

Unclassified

Chapter 4, 

Sections 4.3.1, 

4.3.2

N/A

(B) An assessment of scientific and testing instrumentation for plutonium 

at elemental and bulk conditions.

Unclassified

Chapter 4, 

Sections 4.3.1, 

4.3.2

N/A

(C) An assessment of manufacturing and handling technology for 

plutonium and plutonium components.

Unclassified

Chapter 3, 

Section 3.2.1; 

Appendix E, 

Sections E.2.2, 

E.3.3

N/A

(D) An assessment of computational models of plutonium performance 

under static and dynamic loading, including manufactured and 

nonmanufactured conditions.

Unclassified

Chapter 4, 

Sections 4.2.2, 

4.3.1 - 4.3.4

N/A

(E) An identification of any capability gaps with respect to the assessments 

described in subparagraphs (A) through (D).

Unclassified

Chapter 4, 

Sections 4.3.1 -

4.3.4

N/A

(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.

Unclassified

Chapter 8,

Section 8.5.1, 

8.6.1

N/A

(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.

Unclassified

Chapter 8,

Section 8.5.1, 

8.6.1

N/A

(H) Such other items as the Administrator considers important for the 

integrated management of plutonium for stockpile and stockpile 

stewardship needs.

Unclassified

Chapter 3, 

Section 3.2.1

N/A

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—

Unclassified

Chapter 5

N/A

(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; 

Unclassified

Chapter 5

N/A

(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 

Unclassified

Chapter 5, 

Sections 5.3, 5.4

N/A

(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.

Unclassified

Chapter 8, 

Sections 8.8.3, 

8.8.4

N/A

(8) An assessment of whether the programs described by the report can be 

executed with current and projected budgets and any associated risks.

Unclassified

Chapter 8, 

Sections 8.9, 8.10

N/A

(9) Identification of any modifications or updates to the plan since the 

previous summary or detailed report was submitted under subsection (b).

Unclassified

Chapter 8

N/A
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50 U.S. Code § 2523 FY 2022 Response FY 2023 Response

(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

(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,

Glossary 
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A.3 50 U.S. Code § 2538a

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 2022

Response

FY 2023

Response1

Stockpile Responsiveness Program

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.

Unclassified

Appendix D

Unclassified

Appendix E and 

standalone 

report

1 H. Rept. 117-98 accompanying the Energy and Water Development and Related Agencies Appropriations Bill, 2022 restated this 

annual Stockpile Responsiveness Program (SRP) 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, the Department of Energy’s National Nuclear Security Administration (DOE/NNSA) submitted the 

report as a standalone document in September 2022 to provide as timely updates as possible. This report has been resubmitted 

within the SSMP, as the SSMP is also required to provide information on SRP under 50 USC 2523 and 2523(c)(5), as noted.

50 U.S. Code § 2538a 

FY 2022

Response

FY 2023

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 3.2; 

Chapter 6, 

Section 6.3.1.1; 

Chapter 8, 

Section 8.5.3.1; 

Appendix E, 

Sections E.2.2, E.3.3

Chapter 0,

Executive 

Summary;

Chapter 3,

Section 3.4.1;

Chapter 4,

Section 4.2.1;

Chapter 5,

Section 5.5.3

(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 3.2; 

Chapter 8, 

Section 8.5.3.1

Unclassified

Chapter 3,

Section 3.4.1;

Chapter 5,

Sections 5.5.3, 

5.9.2

(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.5 H.R. 244

H.R.244 – Consolidated Appropriations Act, 2017, P.L. 115-31

FY 2022

Response

FY 2023

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.

(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 
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50 U.S. Code § 2521

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.

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.
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50 U.S. Code § 2524

(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.

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.
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A.10 Related Legislation: S. 4049 NDAA for FY 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.

(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 FY 2022

S. 1605A for FY 2022 NDAA

§ 3135. Reports on risks to and gaps in industrial base for nuclear weapons components, subsystems, and materials

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 

presented as facets of seven interdependent areas, each containing a suite of capabilities that together 

address a particular aspect of Weapons Activities. 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. Chapters 3 and 4 detail the evaluation 

of the four elements of each capability.

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 future stockpile weapons.

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 and Engineering, 

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. This 

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 that 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 life cycle 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. 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 gas transfer system 

reservoirs and inspecting reservoirs. Tritium is also recovered from returned 

gas transfer systems.

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 Handling, packaging, processing, manufacturing, and inspecting components 

that contain lithium materials require special conduct of operations, physical 

security protection, facilities, and equipment.

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. This includes, 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 the components 

and systems required to arm, fuze, fire, and deliver nuclear weapons to their targets. The Weapon 

Component Production area includes the capabilities for producing 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; gas transfer systems; 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 cost 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 the cost and life cycle 

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 of 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. This 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 includes 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 both classified and unclassified 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

Workforce Retention

The greatest asset of the Department of Energy’s National Nuclear Security Administration (DOE/NNSA)

is the highly qualified and skilled world-class scientific and engineering workforce, without which 

DOE/NNSA could not meet its vital national security missions. The workforce simultaneously performs

surveillance, warhead maintenance, technology exploration and maturation, research and development, 

supply chain management, and acquisition, among its modernization programs and other responsibilities. 

Given this workload, attracting and retaining the right talent is critical. This appendix provides the 

summary of human capital retention required in 50 U.S. Code § 2523c(4) and includes an updated 

demographic snapshot (as of September 30, 2021) of the workforce across the nuclear security 

enterprise. A detailed discussion of the DOE/NNSA workforce is contained in Chapter 7 and Appendix D

of the Fiscal Year 2022 Stockpile Stewardship and Management Plan (FY 2022 SSMP).

The nuclear security enterprise continues to grow its Federal and management and operating (M&O) 

partner workforce to meet mission requirements. Like any large organization, DOE/NNSA faces challenges 

regarding its sizeable and diverse workforce. Some of these challenges, notably related to retention, are 

discussed below.

C.1 Challenges and Approaches

DOE/NNSA has made significant progress in hiring, despite several retention challenges: 

◼ Roughly a quarter of the current enterprise workforce is eligible to retire, and there will likely 

remain a significant retirement-eligible population for the near future. See Table C–1 for details.

◼ There is a shortage of U.S. citizens with science, technology, engineering, and math (STEM) skill 

sets, posing a significant challenge to recruiting STEM personnel. DOE/NNSA sites compete with 

the private sector to recruit and retain personnel with highly valued STEM skills (e.g., computer 

science, electrical engineering, and other engineering and science fields). Given demand for these 

skills, qualified applicants can command significant salaries that may exceed the enterprise’s 

ability to match. Nuclear security positions require extensive security screening and U.S. 

citizenship, further limiting the pool of potential applicants.

◼ DOE/NNSA has had continued mission success, despite impacts of the ongoing Coronavirus 

Disease 2019 (COVID-19) pandemic. It remains to be seen how the pandemic may continue to 

impact the enterprise. 
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Table C–1. Federal and site percent retirement-eligible population

as of September 30, 2021

Site % Retirement Eligible1

Federal (across all sites) 15

Los Alamos National Laboratory 38.8

Lawrence Livermore National Laboratory 28.4

Sandia National Laboratories 19.2

Nevada National Security Site 28

Savannah River Site 16.8

Y-12 National Security Complex 27.4

Kansas City National Security Campus 14.2

Pantex Plant 22.2

On an enterprise level, DOE/NNSA’s workforce strategy team, with membership that spans NNSA 

Headquarters, laboratories, plants, and sites, collaborates to find the best solutions to recruit and 

retain the current and future workforce. Partnership and collaboration will be essential to solving 

workforce challenges and maintaining the scientific and technical competencies that underpin 

DOE/NNSA’s national security missions.

NNSA Headquarters, site offices, and M&O partners support retention through a variety of programs: 

◼ Critical skill retention programs to offer pay incentives for hard-to-fill critical positions and 

“reengagement” to attract and rehire recently separated critical talent

◼ Aggressive knowledge transfer programs to provide expertise to newer employees (e.g., the 

Weapons Intern Program transfers detailed weapons and enterprise knowledge to future 

enterprise professionals)

◼ Employee leadership development programs, educational opportunities and assistance, and 

apprentice skill program involvement to encourage career growth

◼ DOE/NNSA Site Directed Research and Development, Plant Directed Research and Development, 

and Laboratory Directed Research and Development funding to encourage new ideas

◼ Emphasis on employee engagement through career conversations, career development tools, 

workshops, and mentoring

◼ Rotational and promotional assignments to diversify experience (e.g., detail assignments to other 

M&O partners or Federal sites)

◼ Improved University relations, partnerships, and scholarship programs

◼ Transition of many programs to a virtual environment when necessary and feasible to support

teleworking and the greater impacts of COVID-19

◼ Flexible work schedules to support family-friendly work/life options (networking groups, fitness 

classes, meetups, etc.)

NNSA Headquarters, site offices, and M&O partners are committed to attracting and retaining top talent. 

1 The definition of “retirement-eligible” varies by location based on bargaining agreements, pension plans, and other factors. The 

differences in definition account for some of the variation between sites.
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C.2 Demographics (Snapshot as of September 30, 2021)

As of September 30, 2021, the enterprise reported a headcount more than 51,0002 employees (Federal 

and M&O partner combined), with a net increase of 2,306 employees from the number reported in the

FY 2022 SSMP. However, the enterprise must continue to hire aggressively to replace employee 

separations (i.e., retirement, voluntary, involuntary). As shown in Figures C–1 and C–2, voluntary 

separations among early-career employees (age 35 and under), mid-career employees (ages 36–50), and 

those with 5 years of service or fewer remain a challenge. As shown in Figures C–3 and C–4, two-thirds 

of the FY 2021 workforce are early- and mid-career, and nearly half of the total workforce have 5 years of 

service or fewer. If current trends continue, the nuclear security enterprise will face challenges training 

these new hires and retaining the talented individuals it recruits.

Figure C–1. Separation by age3

2 This number omits Support Service Contractors and miscellaneous personnel not neatly incorporated into the Common 

Occupational Classification System categories.

3 Workforce data is site-specific. For instance, if a person voluntarily leaves one M&O partner to work at another M&O partner,

that movement appears as a separation and a hire. Similarly, if a Federal employee leaves DOE/NNSA to work at another Federal 

agency, that appears as a voluntary separation.
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Figure C–2. Separation by years of service

Figure C–3. Headcount by age
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Figure C–4. Headcount by years of service

Department of Energy/National Nuclear Security Administration | April 2023

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Appendix D

Exascale

The United States must retain state-of-the-art capabilities in high performance computing (HPC) to 

maintain competitive advantage and perform the annual assessment of the stockpile. HPC will support

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.

Figure D–1. Overview of the DOE/NNSA Exascale Computing Initiative

The National Strategic Computing Initiative was established as a Federal interagency campaign in 2015 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 Science and 

DOE’s National Nuclear Security Administration (DOE/NNSA), has the lead responsibility for focusing and

implementing the joint Exascale Computing Initiative. This initiative focuses on advanced simulation that 
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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.

D.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 what is 

currently the 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)-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 

the 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.

D.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 Exascale Computing Initiative, including 

investments in research and development (R&D) 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 will deliver one

exascale-class system to the DOE Office of Science in fiscal year (FY) 2021–2022 and 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. 

The FY 2023 spend plan for Exascale Computing Initiative elements is delineated in Table D–1. In FY 2023, 

the DOE/NNSA portion of the Exascale Computing Initiative spans across all six ASC program elements: 

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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Advanced Technology Development and Mitigation (ATDM); Integrated Codes; Physics and Engineering 

Models and Verification and Validation, which fund the next-generation simulation technologies for the 

weapons mission; Computational Systems and Software Environment subprogram that procures the 

El Capitan system; and Facility Operation and User Support that funds the site installation work for the 

power-up of El Capitan. Future exascale investments will include improvements to remote tri-lab 

computing infrastructure.

Table D–1. NNSA Exascale Computing Initiative funding schedule for FY 2023

Exascale Computing Initiative Elements

FY 2023 Request

(dollars in millions)

Advanced Technology Development and Mitigation 12

Defense Applications and Modeling 18

Computational Systems and Software Environment 20

Facility Modifications 0

El Capitan Procurement 110

Total, NNSA Exascale Initiative 160

FY = fiscal year

Advanced Technology Development and Mitigation

For FY 2023, the ASC ATDM subprogram is designated as part of the DOE Exascale Computing Project 

(ECP), a jointly managed collaboration between DOE/NNSA and the DOE Office of Science in accordance 

with DOE Order 413.3B (tailored). This portion consists of the ECP Software Technology, in which ASC will 

make strategic investments in software technologies to directly support its IDC development 

requirements, where appropriate. Funding will support further development of compilers, math libraries, 

and programming models for the DOE/NNSA suite of weapons codes that are aligned with the algorithms 

and approaches used in those codes. This focused research is needed to optimize the performance of the 

algorithms within the overall simulations that are the most time-demanding or require the highest

precision control in numerical approximations. Investments also will be made in various performance 

analysis tools and visualization techniques to aid code developers and users to navigate the new advanced 

architecture systems

Defense Application and Modeling – Next-Generation Application Development

In FY 2021, DOE/NNSA began transitioning the viable and validated ATDM 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 2021, DOE/NNSA started the process of transitioning its previously ATDM-funded computing 

technology activities to Computational Systems and Software Environment. DOE/NNSA will continue 

evaluating its next-generation IDC performance portability on advanced architecture prototype systems. 

Funding will be used 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.
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Computational Systems and Software Environment – El Capitan Procurement

DOE/NNSA is 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 2023 

exascale system will be a capable and productive computing resource for the Stockpile Stewardship 

Program. 

D.3 Collaborative Management

As the 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 D–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. 

Figure D–2. Exascale Computing Project integrated project team

D.4 Milestones

DOE/NNSA has five milestones for FY 2023:

◼ Continue engagement with the El Capitan system vendor on system build activities

◼ Begin transition of DOE/NNSA ATDM application codes to the ASC Defense Applications and 

Modeling portfolio to support annual certification and assessment mission

◼ Begin transition of selected DOE/NNSA ATDM computing technologies to its Computational 

Systems and Software Environment portfolio

◼ Operate El Capitan early access system-3 nodes sited at Lawrence Livermore National Laboratory

◼ Port ATDM application codes to El Capitan early access system-3 nodes to analyze potential 

performance issues
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D.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 R&D

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 has 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 now rely on. More intensive research, development, and engineering effort is needed for 

DOE/NNSA to achieve the goal of deploying and fully utilizing an exascale capability in 2023.

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Appendix E

Stockpile Responsiveness Program

This appendix is provided pursuant to 50 U.S. Code § 2523, which requires inclusion of plans for the 

Stockpile Responsiveness Program in the Stockpile Stewardship and Management Plan (SSMP). H. Rept. 

117-98 accompanying the Energy and Water Development and Related Agencies Appropriations Bill, 

2022, restated an annual Stockpile Responsiveness Program reporting requirement and noted that as the 

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. Therefore, in accordance with this direction, the Department 

of Energy’s National Nuclear Security Administration submitted the report as a standalone document in 

September 2022 to provide as timely updates as possible. This report is being resubmitted through this 

appendix, as the SSMP is also required to provide information on the Stockpile Responsiveness Program 

under 50 U.S. Code 2523 and 2523(c)(5), as noted above.
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Appendix F

Industrial Base

F.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, 

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. The activities 

listed under the pillars in Figure F–1 indicate the types of activities that are considered when examining 

the NIB. 

Figure F–1. The nuclear security enterprise industrial base framework

F.2 Risk Management

Risk management is an area of increased attention across the nuclear security enterprise. Programs and 

sites within the enterprise employ varying methods to identify, characterize, monitor, and manage risks. 

These include efforts such as program-specific risk matrices; supply chain focused risk matrices that track 
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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 that is working to standardize the methods used to identify, monitor, and 

respond to supply chain risks. The Supply Chain Risk Management Team supports larger DOE/NNSA 

initiatives that are addressing all the pillars of the NIB to create an overarching process to make risk 

management practices more rigorous. 

F.2.1 Monitoring

The NIB is complex and multi-faceted; many diverse groups within the enterprise are monitoring and 

acting on industrial base issues that are specific to their own programs or activities. This necessarily 

narrow focus does not always offer a broad view of the industrial base picture. Therefore, as a part of a 

more centralized industrial base management focus, DOE/NNSA leverages its Integrated Planning Group 

to increase data sharing across the various program offices, working groups, and teams to increase 

coordination and collaboration and to gain more detailed insight concerning industrial base challenges. 

In addition, information sharing occurs across the enterprise in areas such as risk management and issues 

related to the industrial base, as well as reciprocity of vendor qualifications to reduce the burden on 

vendors who do business with multiple laboratories, plants, or sites.

F.2.2 Mitigation

Within the Stockpile Stewardship and Management Plan – Biennial Plan Summary, 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 follow:

◼ Supply Chain challenges are discussed throughout but primarily in Chapter 3, “Weapons Activities 

Capabilities.”

◼ Operations and Facilities challenges are discussed primarily in Chapter 3, “Weapons Activities 

Capabilities”; Chapter 4, “Infrastructure and Operations”; and Chapter 5, Section 5.7, 

“Infrastructure and Operations.”

◼ Logistics and Transportation challenges are primarily discussed in Chapter 2, “Stockpile 

Management”; and Chapter 3, Section 3.7, “Transportation and Security Portfolio.”

◼ Workforce challenges are primarily discussed in Chapter 3, “Weapons Activities Capabilities”; and 

Appendix C, “Workforce Retention.”

F.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 
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to review the transaction; DOE is a lead on approximately 25 percent of transaction reviews, mostly in the 

energy sector, but with numerous cases impacting the nuclear weapons complex annually. 

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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 (Alt)—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 highpressure 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 DOE 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 (DU)—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 6.X Process,

culminating in a final design (normally exercised when moving from Phase 6.1 to 6.2, from Phase 6.2 to 

6.2A, and from Phase 6.2A to 6.3). Down-selecting involves analysis of the option’s ability to meet military 

requirements, and assessment of schedule, cost, material, and production impacts. 

electrorefining—An electrochemical metal purification system designed to provide a replacement 

capability for the current metal purification process.
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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 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) DoD or the 

Nuclear Weapons Council accepts the design and (2) DOE/NNSA verifies that the first produced weapon 

meets the design specifications. 

fiscal year (FY)—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 (FYNSP)—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 (GTS)—A warhead component that enables tritium, a radioactive isotope of hydrogen, 

to boost the yield of a nuclear weapon. 

high energy density (HED) 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. High explosives 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 (HPC)—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 (IT)—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 SSMP, 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 (IHE)—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 (JTA)—(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) An NNSA-developed configuration, based on NNSA-DoD requirements, for use in the

flight test program.

life cycle—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.

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.

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 (LLC)—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—A means of communicating the degree to which a component or 

subsystem is ready to be produced. Manufacturing Readiness Levels represent many attributes of a 

manufacturing system (e.g., people, manufacturing capability, facilities, conduct of operations, and 

tooling). There are nine Manufacturing Readiness Levels, 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 DOE/NNSA 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. 

Nuclear Weapons Council—The joint DOE/DoD 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.
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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 (OPM)—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 6.X Process—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. The Phase 6.X Process consists of sub-phases that correspond to 

Phases 1 through 6 of the nuclear weapons life cycle.

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.)

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.
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Safeguards Transporter (SGT)—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 DOE’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 (SFI)—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.

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 lifecycle. 

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.
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sustainment—An NNSA 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.

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.

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 NNSA budget covering these activities. 
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page H-1

Appendix H

Acronyms and Abbreviations

ACRR Annular Core Research Reactor

Alt alteration

AoA Analysis of Alternatives

ASC Advanced Simulation and Computing

ASD Advanced Sources and Detectors

ATDM Advanced Technology Development and Mitigation

BCR Baseline Cost Report

CAS Central Alarm Station

CBI Capability Based Investments

CD Critical Decision

CFF Contained Firing Facility

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

D&I disassembly and inspection

DA-PA design agency-production agency

DARHT Dual-Axis Radiographic Hydrodynamic Test

DIW Direct Ink Write

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

ECP Exascale Computing Project

ECSE Enhanced Capabilities for Subcritical Experiments

FY fiscal year

FYNSP Future Years Nuclear Security Program

GAO Government Accountability Office

GTS gas transfer system

HE high explosives

HE&E high explosives and energetics

HED high energy density

HESE high explosives science and engineering

HEU highly enriched uranium

HPC high performance computing

HPDU high purity depleted uranium
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page H-2

HSE hydrodynamic and subcritical experiments

ICF inertial confinement fusion

IDC integrated design code

IMI Infrastructure Modernization Initiative

IT information technology

IWEC Integrated Weapon Evaluation Capability

JTA joint test assembly

KCNSC Kansas City National Security Campus

kV kilovolt

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

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

Mod modification

MRL manufacturing readiness level

NEA Nuclear Enterprise Assurance

NIB nuclear security enterprise industrial base

NIF National Ignition Facility

NNSA National Nuclear Security Administration

NNSS Nevada National Security Site

OCIO Office of the Chief Information Officer

OMB Office of Management and Budget

Omega Omega Laser Facility

OT operational technologies

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

S&S Safeguards and Security

SAR Selected Acquisition Report

SFI significant finding investigation

SGT Safeguards Transporter

SIRP Security Infrastructure Revitalization Program

SLCM Sea-launched Cruise Missile

SME subject matter expert

SNL Sandia National Laboratories
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page H-3

SNM special nuclear material

SRPPF Savannah River Plutonium Processing Facility

SRS Savannah River Site

SRT&E Stockpile Research, Technology, and Engineering

SSMP Stockpile Stewardship and Management Plan

STA Secure Transportation Asset

STEM science, technology, engineering, math

STS stockpile-to-target sequence

TA Technical Area

TPBAR tritium-producing burnable absorber rod

TRL technology readiness level

TVA Tennessee Valley Authority

U1a U1a Complex

USSTRATCOM U.S. Strategic Command

WBN Watts Bar nuclear reactors

WDCR Weapon Design and Cost Report

WDD Weapons Dismantlement and Disposition

WEPAR West End Protected Area Reduction

WR War Reserve

Y-12 Y-12 National Security Complex

Z Z pulsed power facility

Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page I-1

Appendix I

List of Figures and Tables

List of Figures

Figure 1–1. Size and age of the U.S. nuclear weapons stockpile, 1945–2020........................................................1-4

Figure 1–2. Integrated stockpile model..................................................................................................................1-7

Figure 1–3. Timeline for key infrastructure and capability investments for future warheads...............................1-9

Figure 2–1. Major Stockpile Management Programs.............................................................................................2-2

Figure 2–2. DOE/NNSA Warhead Activities............................................................................................................2-7

Figure 2–3. Phase X and Phase 6.X Processes.........................................................................................................2-9

Figure 3–1. DOE/NNSA Weapons Activities capability areas..................................................................................3-2

Figure 3–2. Weapons Activities capability elements..............................................................................................3-2

Figure 3–3. High Purity Depleted Uranium supply chain......................................................................................3-31

Figure 3–4. Depleted Uranium Modernization Process flow chart ......................................................................3-32

Figure 3–5. Information Technology and Cybersecurity major elements and initiatives.....................................3-54

Figure 4–1. DOE/NNSA infrastructure size and scope............................................................................................4-2

Figure 4–2. Asset management life cycle ...............................................................................................................4-2

Figure 4–3. Critical Decision process......................................................................................................................4-6

Figure 4–4. Historical and projected average age of all DOE/NNSA facilities.........................................................4-7

Figure 4–5. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Science and Engineering .......................................................................................................4-8

Figure 4–6. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Simulation and Computing..................................................................................................4-10

Figure 4–7. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Design and Integration........................................................................................................4-11

Figure 4–8. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Material Processing and Manufacturing .............................................................................4-13

Figure 4–9. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Component Production.......................................................................................................4-15

Figure 4–10. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Weapon Assembly, Storage, Testing, and Disposition.......................................................................4-16

Figure 4–11. 25-year programmatic line-item schedule for ongoing and proposed projects related to 

Transportation and Security ..............................................................................................................4-17

Figure 4–12. 25-year mission-enabling line-item schedule....................................................................................4-19

Figure 5–1. FY 2023 President’s Budget Request for Stockpile Management........................................................5-4

Figure 5–2. Key milestones for Stockpile Management.........................................................................................5-6

Figure 5–3. FY 2023 President’s Budget Request for Production Modernization ..................................................5-7

Figure 5–4. Key milestones for Primary Capability Modernization ......................................................................5-10

Figure 5–5. Key milestones for Secondary Capability Modernization..................................................................5-11
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page I-2

Figure 5–6. Key milestones for Tritium Modernization and Domestic Uranium Enrichment ..............................5-12

Figure 5–7. Key milestones for Non-Nuclear Capability Modernization ..............................................................5-13

Figure 5–8. FY 2023 President’s Budget Request for Stockpile Research, Technology, and Engineering ............5-14

Figure 5–9. Key milestones for Stockpile Research, Technology, and Engineering..............................................5-17

Figure 5–10. FY 2023 President’s Budget Request for Infrastructure and Operations ..........................................5-18

Figure 5–11. FY 2023 President’s Budget Request for Other Weapons Activities..................................................5-22

Figure 5–12. Key milestones for Secure Transportation Asset...............................................................................5-23

Figure 5–13. Key milestones for Defense Nuclear Security....................................................................................5-24

Figure 5–14. Key milestones for Information Technology and Cybersecurity........................................................5-26

Figure 5–15. Cost estimates across the Phase 6.X Process.....................................................................................5-27

Figure 5–16. B61-12 Life Extension Program cost from FY 2009 to completion ....................................................5-31

Figure 5–17. W88 Alteration 370 Program (with conventional high explosive refresh) from FY 2013 

to completion ....................................................................................................................................5-32

Figure 5–18. W80-4 Life Extension Program cost from FY 2015 to completion.....................................................5-33

Figure 5–19. W87-1 Modification Program cost from FY 2019 to completion.......................................................5-34

Figure 5–20. Total projected Stockpile Major Modernization costs for FY 2022–FY 2047 with high 

and low estimates (then-year dollars)...............................................................................................5-36

Figure C–1. Separation by age ............................................................................................................................... C-3

Figure C–2. Separation by years of service............................................................................................................ C-4

Figure C–3. Headcount by age............................................................................................................................... C-4

Figure C–4. Headcount by years of service............................................................................................................ C-5

Figure D–1. Overview of the DOE/NNSA Exascale Computing Initiative ............................................................... D-1

Figure D–2. Exascale Computing Project integrated project team........................................................................ D-4

Figure F–1. The nuclear security enterprise industrial base framework................................................................F-1
Department of Energy/National Nuclear Security Administration | April 2023

Fiscal Year 2023 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page I-3

List of Tables

Table 1–1. Current U.S. nuclear weapons and associated delivery systems.........................................................1-4

Table 3–1. Summary of the Weapon Science and Engineering area challenges and strategies........................ 3-11

Table 3–2. Summary of the Weapon Simulation and Computing area challenges and strategies .................... 3-19

Table 3–3. Summary of the Weapon Design and Integration area challenges and strategies........................... 3-23

Table 3–4. Summary of plutonium handling, packaging, and processing challenges and strategies................. 3-28

Table 3–5. Summary of highly enriched uranium handling, packaging, and processing challenges 

and strategies ................................................................................................................................... 3-30

Table 3–6. Summary of depleted uranium modernization challenges and strategies....................................... 3-32

Table 3–7. Summary of domestic uranium enrichment challenges and strategies ........................................... 3-34

Table 3–8. Summary of lithium handling, packaging, and processing challenges and strategies...................... 3-36

Table 3–9. Summary of the tritium production, handling, and processing challenges and strategies.............. 3-38

Table 3–10. Summary of the high explosives and energetics management challenges and strategies............... 3-40

Table 3–11. Summary of non-nuclear capability modernization challenges and strategies................................ 3-44

Table 3–12. Summary of the Weapon Component Production area challenges and strategies.......................... 3-48

Table 3–13. Summary of Weapon Assembly, Storage, Testing, and Disposition area challenges 

and strategies ................................................................................................................................... 3-50

Table 3–14. Summary of Secure Transportation Asset challenges and strategies............................................... 3-52

Table 3–15. Summary of Safeguards and Security challenges and strategies...................................................... 3-53

Table 3–16. Summary of Information Technology and Cybersecurity challenges and strategies........................ 3-55

Table 5–1. Overview of Future Years Nuclear Security Program budget request for Weapons Activities 

in FY 2021–FY 2027..............................................................................................................................5-3

Table 5–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant Value.............................5-20

Table 5–3. Projected FY 2023 DOE/NNSA infrastructure maintenance and recapitalization investments.........5-21

Table 5–4. DOE/NNSA cost estimates for Stockpile Major Modernization Programs ........................................5-29

Table 5–5. Total estimated cost for B61-12 Life Extension Program ..................................................................5-31

Table 5–6. Total estimated cost for W88 Alteration 370 Program (with conventional 

high explosive refresh).......................................................................................................................5-32

Table 5–7. Total estimated cost for W80-4 Life Extension Program...................................................................5-33

Table 5–8. Total estimated cost for W87-1 Modification Program.....................................................................5-34

Table 5–9. Total estimated cost for W93 Program (Option 2A)..........................................................................5-35

Table 5–10. Total estimated cost for Future Strategic Missile – Land-Based Warhead (FSLW)............................5-35

Table 5–11. Total estimated cost for Future Strategic Missile – Sea-Based Warhead..........................................5-35

Table 5–12. Total estimated cost for Future Air-Delivered Weapon ....................................................................5-35

Table 5–13. Capital Acquisition Cost Estimate Classification System....................................................................5-38

Table 5–14. Weapons Activities capital acquisition estimated costs, FY 2023–FY 2047.......................................5-38

Table C–1. Federal and site percent retirement-eligible population as of September 30, 2021 ......................... C-2

Table D–1. NNSA Exascale Computing Initiative funding schedule for FY 2023 ................................................... D-3


A Report to Congress

Fiscal Year 2023 Stockpile Stewardship and 

Management Plan – Biennial Plan Summary

April 2023

U.S. Department of Energy

National Nuclear Security Administration

1000 Independence Avenue, SW

Washington, DC 20585

DOE/NA-0128