Fiscal Year 2021 

Stockpile Stewardship and 

Management Plan – Biennial 

Plan Summary

Report to Congress

December 2020 

National Nuclear Security Administration 

United States Department of Energy 

Washington, DC 20585 

Department of Energy/National Nuclear Security Administration | December 2020

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page i 

Message from the NNSA Administrator 

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

safeguard and support our Nation’s security through the application of nuclear science and engineering. 

Since the days of the Manhattan Project, the highly talented men and women of the nuclear security 

enterprise have applied unique capabilities to promote U.S. security in the face of an ever-evolving global 

security environment. 

Nuclear deterrence has been, and remains, the cornerstone of our Nation’s security posture, and its 

credibility serves as the ultimate insurance policy against a nuclear attack. DOE/NNSA is the only 

organization that can sustain the Nation’s nuclear stockpile, as well as the nuclear propulsion systems of 

the U.S. Navy’s submarines and aircraft carriers. We are the industrial base for the Nation’s nuclear 

stockpile, and providing the tools of deterrence to our Nation’s military is DOE/NNSA’s highest-priority 

mission. 

The Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary (SSMP) 

describes DOE/NNSA’s plans to ensure the safety, security, and effectiveness of the U.S. nuclear weapons 

stockpile and to maintain the scientific and engineering tools, capabilities, and infrastructure that 

underpin the nuclear security enterprise. NNSA also publishes the annual Prevent, Counter, and Respond: 

A Strategic Plan to Reduce Global Nuclear Threats report to Congress as a companion document to the 

SSMP, which outlines the equally vital missions to reduce the threats of nuclear proliferation and nuclear 

terrorism. In keeping with our commitments to Congress and the public, updated versions of these 

reports are published each year. 

The fiscal year (FY) 2021 SSMP summarizes the activities being performed within DOE/NNSA’s national 

laboratories, production facilities, and security sites in support of our national security missions. In 

particular, this report describes DOE/NNSA’s plan to achieve the program requirements of producing 80 

plutonium pits per year during 2030; achieving the first production unit of the W80-4 Life Extension 

Program and W87-1 Modernization Program by FY 2025 and FY 2030, respectively; and delivering the first 

production units of the B61-12 Life Extension Program and the W88 Alteration 370 warheads. 

In FY 2020, DOE/NNSA closed out the W76-1 Life Extension Program, provided the W76-2 low-yield 

ballistic missile warhead for initial deployment, and restarted design activities for the W78 replacement 

warhead (the W87-1) program that resumed in FY 2019. The nuclear security enterprise is at its busiest 

since the Cold War. 

DOE/NNSA’s ability to execute the priorities outlined in the 2018 Nuclear Posture Review depends upon 

a modern, flexible, and resilient nuclear security infrastructure, as outlined in the 2019 DOE/NNSA Nuclear 

Posture Review Implementation Plan report to Congress. This SSMP reflects continued investments in 

repair and recapitalization of the laboratories, production facilities, and security sites that are crucial to 

delivering on the Nation’s defense priorities and, most importantly, to supporting our greatest asset, our 

workforce. Together with continued support from Congress, DOE/NNSA will ensure that its world-class 

workforce has the resources and the responsive, agile infrastructure needed to steward the systems that 

comprise our deterrent today and, should the need arise, to design the systems of tomorrow. 

The rapidly evolving threat environment facing our Nation underscores the need for the United States to 

maintain a diverse set of nuclear capabilities that can provide flexible, tailored options to enhance 
Department of Energy/National Nuclear Security Administration | December 2020 

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page ii 

deterrence and achieve national security objectives should deterrence fail. As described in this report, 

the scientific and technological expertise found at DOE/NNSA’s laboratories, production facilities, and 

other sites is the intellectual backbone that supports the United States’ continued deterrence of 

adversarial aggression and the preservation of peace for our Nation and our allies. 

For 75 years, the nuclear security enterprise has met every challenge, leading the country in incredible 

scientific and engineering endeavors and discoveries that benefit the Nation as a whole. As we continue 

into the next decade, DOE/NNSA will continue to stand together to anticipate future security challenges 

and ensure that our Nation is ready to meet them. 

Pursuant to statute, this FY 2021 SSMP is provided to: 

The Honorable Richard Shelby 

Chairman, Senate Committee on Appropriations 

The Honorable Patrick Leahy 

Vice Chairman, Senate Committee on Appropriations 

The Honorable James Inhofe 

Chairman, Senate Committee on Armed Services 

The Honorable Jack Reed 

Ranking Member, Senate Committee on Armed Services 

The Honorable Lamar Alexander 

Chairman, Subcommittee on Energy and Water Development 

Senate Committee on Appropriations 

The Honorable Dianne Feinstein 

Ranking Member, Subcommittee on Energy and Water Development 

Senate Committee on Appropriations 

The Honorable Deb Fischer 

Chairman, Subcommittee on Strategic Forces 

Senate Committee on Armed Services 

The Honorable Martin Heinrich 

Ranking Member, Subcommittee on Strategic Forces 

Senate Committee on Armed Services 

The Honorable Nita Lowey 

Chairman, House Committee on Appropriations 

The Honorable Kay Granger 

Ranking Member, House Committee on Appropriations 

The Honorable Adam Smith 

Chairman, House Committee on Armed Services 

The Honorable Mac Thornberry 

Ranking Member, House Committee on Armed Services 
Department of Energy/National Nuclear Security Administration | December 2020 

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page iii 

The Honorable Marcy Kaptur 

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

House Committee on Appropriations 

The Honorable Mike Simpson 

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

House Committee on Appropriations 

The Honorable Jim Cooper 

Chairman, Subcommittee on Strategic Forces

House Committee on Armed Services 

The Honorable Michael Turner 

Ranking Member, Subcommittee on Strategic Forces 

House Committee on Armed Services 

Should you have any questions or need additional information, please contact Dr. Howard Dickenson, 

Acting Associate Administrator for External Affairs, at (202) 586-7332; or Ms. Katie Donley, Deputy 

Director for External Coordination, Office of the Chief Financial Officer, at (202) 586-0176. 

 Sincerely, 

 William A. Bookless 

 Acting Under Secretary for Nuclear Security 

 And Administrator, NNSA 

 
Department of Energy/National Nuclear Security Administration | December 2020 

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Department of Energy/National Nuclear Security Administration I December 2020 

Message from the Secretary 

The Department of Energy's National Nuclear Security Administration (DOE/NNSA) was established 20 

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

and engineering. Since that time, DOE/NNSA has successfully maintained a safe, secure, and effective 

nuclear deterrent in close coordination with the Department of Defense. 

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

return to great power competition in the 21st century, coupled with an unprecedented range and mix of 

threats, requires the United States to maintain a diverse set of nuclear deterrent capabilities. The Nation 

must also maintain the means to provide flexible, tailored options to achieve national security objectives 

should deterrence fail. To provide a viable nuclear deterrent, the United States must maintain the current 

stockpile of nuclear weapons, extend the life of the stockpile, and sustain the nuclear deterrent in the 

long term through the modernization of laboratory and production infrastructure. 

Over the past several decades, necessary weapon and infrastructure modernization program investments 

have been postponed for competing priorities. These delays in investments have directly affected 

DOE/NNSA's ability to maintain critical capabilities, recapitaliz�_modernize deteriorating 

infrastructure, and recruit and retain the workforce necessaryto ensure the future viability of the 

deterrent. This Administration is committed to reversing these trends and investing to support a truly 

responsive and resilient nuclear security enterprise. 

DOE/NNSA's Fiscal Year 2021 Stockpile Stewardship and Management Pion - Biennial Summary {SSMP}

outlines the extensive work DOE/NNSA will undertake to modernize the stockpile; strengthen its 

significant scientific, technical, and engineering capabilities; and recapitalize supporting infrastructure to 

support the nuclear deterrent's modernization now and into the future. With the continued support of 

Congress, this program will revitalize and reinvigorate the nuclear security enterprise and ensure the 

safety, security, and effectiveness of the nuclear deterrent for the next 25 years and beyond. 

Sincerely, 

Dan Brouillette 

Fiscal Year 2021 Stockpile Stewardship and Management Plan - Biennial Plan Summary I Page v 
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Executive Summary 

This Fiscal Year 2021 Stockpile Stewardship and Management Plan (SSMP), including its classified Annex,

describes the Department of Energy/National Nuclear Security Administration (DOE/NNSA) program for 

maintaining the safety, security, and effectiveness of the nuclear stockpile 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 for Weapons Activities. This fiscal year 

(FY) 2021 SSMP is a summary report. This annual plan provides a single, integrated picture of current and 

future nuclear security enterprise activities and capabilities funded by the Weapons Activities account in 

support of the Nation’s nuclear deterrent and is developed to be consistent with the Nuclear Weapons 

Council Strategic Plan for FY 2019–2044.

This SSMP reflects a rigorous mapping of the military requirements and nuclear security enterprise needs 

to assure an effective deterrent, and meet the nuclear deterrent objectives laid out in the National 

Security Strategy (White House 2017) and the 2018 Nuclear Posture Review. 

Maintaining a safe secure, and effective nuclear weapons stockpile is one of several DOE/NNSA enduring 

missions, which also include reducing global nuclear threats, and providing the Navy’s submarines and 

aircraft carriers with militarily effective nuclear propulsion. To accomplish these missions, DOE/NNSA 

must maintain a range of flexible nuclear capabilities that can only be realized through a world-class 

scientific and engineering workforce operating in a modern, resilient, and responsive nuclear 

infrastructure. The National Nuclear Security Administration Strategic Vision (NNSA 2019) lays out five 

mission priorities, three of which are directly relevant to the nuclear deterrent. Highlights of near-term 

and out-year mission milestones and accomplishments for these mission priorities are: 

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

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

complex component development and production work. 

Near-Term and Out-Year Mission Goals: 

 Deliver the B61-12 gravity bomb 

 Deliver the W88 Alteration 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 Department of Defense (DoD) long range standoff cruise missile replacement 

program 

 Support fielding the Ground-Based Strategic Deterrent and advance the W87-1 Modification 

Program (formerly called the W78 Replacement Warhead) 

 Sustain the B83-1 gravity bomb until a suitable replacement is identified 

 Provide the enduring capability to produce 80 plutonium pits per year during 2030 by expanding 

plutonium pit production capabilities 

 Assure a continuous and reliable supply of strategic nuclear weapon components and the key 

materials that make up the components, to include plutonium, uranium, lithium, tritium, and high 

explosives 

 Provide experimental and computational capabilities to support annual assessment and 

certification of the stockpile 
Department of Energy/National Nuclear Security Administration | December 2020 

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Key Accomplishments: 

 The W76-1 LEP was completed under budget and ahead of schedule, strengthening the Nation’s 

safety and security by extending the warhead’s service life from 20 years to 60 years. 

 The W76-2 warheads were delivered to the Navy. A modification of the W76-1, the W76-2 

supports the low-yield, sea-launched ballistic missile capability called for in the 2018 Nuclear 

Posture Review. 

 The W80-4 LEP entered Phase 6.3, Development Engineering, in FY 2019. 

 In FY 2019, five additional developmental plutonium pits, a key component of nuclear weapons, 

were completed at Los Alamos National Laboratory (LANL), in Los Alamos, New Mexico, in support 

of DOE/NNSA’s strategic effort to revitalize U.S. pit production capability. 

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 

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 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 effects of plutonium aging on weapon performance over time 

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

 Maintain state-of-the-art manufacturing technologies in support of production operations 

 Implement the Stockpile Responsiveness Program to fully exercise the workforce and capabilities 

of the nuclear security enterprise 

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

long-term capabilities and workforces of the national security laboratories, production plants, and 

sites 

Key Accomplishments: 

 DOE/NNSA signed a $600 million contract for its first exascale supercomputer, El Capitan, slated 

to be delivered at the end of 2022 and projected to be operational in 2023 at Lawrence Livermore 

National Laboratory, in Livermore, California, to support NNSA’s weapons programs. 

 DOE/NNSA approved the conceptual design and cost range, or Critical Decision 1 (CD-1; Approve 

Alternative Selection and Cost Range), for the Advanced Sources and Detectors (ASD) project 

within the Enhanced Capabilities for Subcritical Experiments portfolio. ASD will lead to a more 

robust Stockpile Stewardship Program by generating high-speed, high-fidelity X-ray images of 
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subcritical experiments. This capability will support warhead modernization, certification, and 

stockpile assessments. 

 The Kansas City National Security Campus (KCNSC) used microreactor technology to create a type 

of Trigonox, which is used in the production of nuclear weapons parts but is no longer 

commercially available. 

 DOE/NNSA announced an additional $5 million investment in developing future employees to 

carry out vital missions at the Savannah River Site (SRS) near Aiken, South Carolina. The 

Workforce Opportunities in Regional Careers Grant supports programs at five post-secondary 

education institutions around the site, including its first historically black college or university, 

Claflin University. 

 DOE/NNSA funded over $100 million in grants and cooperative agreements with top universities 

across the country, such as the Stewardship Science Academic Alliances Program and the Minority 

Serving Institution Partnership Program. 

 The Z pulsed power facility successfully measured temperature on dynamically compressed 

plutonium in a regime relevant for primary performance. 

 National Ignition Facility operations enabled the completion of several high-energy-density 

science campaigns for stockpile stewardship, including radiation-transport studies in support of 

the W80-4 LEP and the first plutonium equation of state experiment on the National Ignition 

Facility, a culmination of platform development that will enable plutonium experiments to inform 

issues associated with plutonium pit lifetimes. 

 Developed methods to characterize explosives in support of the W80-4 LEP. 

Modernize the Nuclear Security Infrastructure 

DOE/NNSA continues to revitalize and reinvigorate the facilities and corresponding infrastructure that 

make up the nuclear security enterprise. These upgrades are necessary to create a responsive and 

resilient nuclear enterprise that can meet national security missions today and into the future. 

Near-Term and Out-Year Mission Goals: 

 Recapitalize existing infrastructure to implement a plan to produce 80 pits per year during 2030. 

The recommended strategy is a two-site solution: 

– Produce 30 pits per year at the Plutonium Facility at LANL, beginning in 2026 

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

Plutonium Processing Facility to produce 50 pits per year during 2030 

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

(Y-12) in Oak Ridge, Tennessee, by relocating the facility’s enriched uranium processing 

capabilities into existing facilities and the Uranium Processing Facility and extend the operational 

lifetime of key existing facilities into the 2040s 

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

Metallurgy Research Replacement project 

 Modernize lithium facilities 

 Modernize tritium facilities 

 Increase production of tritium using two reactors to meet stockpile needs 
Department of Energy/National Nuclear Security Administration | December 2020 

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 Recapitalize the high explosive 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 the ASD Major Item of Equipment. 

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

maintain capabilities of the nuclear weapons stockpile 

 Reduce deferred maintenance and required repairs by not less than 30 percent by 2025 

Key Accomplishments: 

 Construction of Uranium Processing Facility at Y-12 remains on budget and on schedule. 

 NNSA completed a tool upgrade at the Sandia National Laboratories (SNL) facility in Albuquerque, 

NM responsible for making integrated circuits that will enable continued production using current 

supply chain materials. 

 NNSA produced the first high explosive part at the new High Explosives Pressing Facility at the 

Pantex Plant near Amarillo, TX after DOE/NNSA authorized full-scale operations. The modern 

45,000 square-foot facility replaces infrastructure that is over 50 years old, improving worker 

safety. 

 NNSA finished the exterior structure of the Albuquerque Complex which will provide a modern, 

safe, and reliable workspace to approximately 1,200 employees. 

 NNSA completed the award and construction of its first new-construction, net-zero energy facility, 

Mercury Building 1, powered from the Mercury solar field at the Nevada National Security Site 

near Las Vegas, Nevada. 

 DOE/NNSA began using its BUILDER software, revolutionizing management of infrastructure and 

maintenance and allowing the agency to track the status of over 3,000 buildings across the nuclear 

security enterprise. Using BUILDER provides more accurate, timely, consistent, comprehensive, 

and risk-based data on infrastructure condition and costs than historical approaches and will 

greatly improve management of deferred maintenance. 

 NNSA completed CD-0, Approve Mission Need, for the Power Sources Capability and Combined 

Radiation Environments Survivability Testing Complex at SNL. 

 NNSA completed CD-1 for the Lithium Processing Facility at Y-12. 

 NNSA completed CD-1 for the Tritium Finishing Facility at SRS. 

Challenges in Executing the Stockpile Stewardship and Management Plan 

DOE/NNSA and DoD together deliver the capabilities that will provide the Nation with the ability to adapt 

and respond to a dynamic security environment, emerging strategic challenges, and geopolitical and 

technological changes. Weapon Activities capabilities are the foundational mechanisms for achieving 

mission deliverables and priorities. DOE/NNSA must continue to invest in advancing existing capabilities 

and developing emerging capabilities to assure a strong nuclear deterrent. A summary of the required 

capabilities and their current status is found in Chapter 3. 

Major aspects of DOE/NNSA’s capabilities are overdue for replacement or recapitalization to ensure a 

modern, responsive, and resilient nuclear security enterprise that can meet the U.S. national security 

missions today and into the future. Many key facilities that enable weapon activity capabilities must be 

replaced or reinvigorated as they do not meet modern safety standards and require significantly increased 
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investment to maintain them. This is particularly critical for the production capabilities of the nuclear 

security enterprise necessary to meet DoD warhead deliverables. The NNSA continue to invest in 

modernizing and developing the nuclear security enterprise’s capabilities and supporting infrastructure. 

 
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Fiscal Year 2021 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 Policy Framework Summary .................................................................................................... 1-2 

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

1.3 Overall Strategy and Goals of Weapons Activities ................................................................... 1-4 

1.4 Summary of Key Challenges in Implementing the Stockpile Stewardship and 

Management Plan .................................................................................................................... 1-5 

Chapter 2 Managing the Stockpile ..................................................................................................2-1 

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

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

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

2.1.3 Maintaining the Stockpile .......................................................................................... 2-5 

2.2 Stockpile Major Modernization ............................................................................................... 2-5 

2.2.1 W76-1 Life Extension Program .................................................................................. 2-7 

2.2.2 W76-2 Modification Program .................................................................................... 2-7 

2.2.3 W88 Alteration 370 Program ..................................................................................... 2-7 

2.2.4 B61-12 Life Extension Program ................................................................................. 2-8 

2.2.5 W80-4 Life Extension Program .................................................................................. 2-8 

2.2.6 W87-1 Modification Program .................................................................................... 2-9 

2.2.7 Sea-Launched Cruise Missile ...................................................................................2-10 

2.2.8 W93..........................................................................................................................2-10 

2.2.9 Future Warheads .....................................................................................................2-10

2.3 Weapon Dismantlement and Disposition ..............................................................................2-10 

2.4 Production Operations ...........................................................................................................2-11 

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

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

3.1 Weapons Activities Capabilities in Context ............................................................................. 3-1 

3.2 Weapons Activities Capabilities ............................................................................................... 3-2 

3.3 Weapon Material Processing and Manufacturing Portfolio .................................................... 3-3 

3.3.1 Special Nuclear Materials Handling, Packaging, and Processing 

(Plutonium and Uranium) .......................................................................................... 3-4 
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3.3.2 Tritium Production, Handling, and Processing ........................................................ 3-10 

3.3.3 Energetic and Hazardous Material Handling, Packaging, Processing, and 

Manufacturing (High Explosives and Lithium) ......................................................... 3-12 

3.3.4 Metal and Organic Material Fabrication, Processing, and Manufacturing ............. 3-16 

3.4 Weapon Component Production Portfolio ............................................................................ 3-16 

3.4.1 Non-Nuclear Component Production ...................................................................... 3-16 

3.4.2 Weapon Component and Material Process Development ...................................... 3-18 

3.4.3 Weapon Component and System Prototyping ........................................................ 3-19 

3.4.4 Advanced Manufacturing ........................................................................................ 3-21 

3.5 Weapon Simulation and Computing Portfolio ....................................................................... 3-23 

3.5.1 Status of Weapon Simulation and Computing Portfolio ......................................... 3-24 

3.5.2 Challenges and Strategies ........................................................................................ 3-25 

3.6 Weapon Design and Integration Portfolio ............................................................................. 3-26 

3.6.1 Weapons Physics Design and Analysis..................................................................... 3-26 

3.6.2 Weapons Engineering Design, Analysis, and Integration ........................................ 3-27 

3.6.3 Environmental Effects Analysis, Testing, and Engineering Sciences ....................... 3-29 

3.6.4 Weapons Surety Design, Testing, Analysis, and Manufacturing ............................. 3-30 

3.6.5 Radiation-Hardened Microelectronics Design and Manufacturing ......................... 3-30 

3.7 Weapon Science and Engineering Portfolio ........................................................................... 3-31 

3.7.1 Nuclear Physics and Engineering ............................................................................. 3-32 

3.7.2 Radiochemistry ........................................................................................................ 3-32 

3.7.3 Atomic and Plasma Physics ...................................................................................... 3-33 

3.7.4 High Energy Density Physics .................................................................................... 3-34 

3.7.5 Laser and Optical Science, Technology, and Engineering ........................................ 3-35 

3.7.6 Accelerator and Pulsed Power Science, Technology, and Engineering ................... 3-36 

3.7.7 Advanced Experimental Diagnostics and Sensors ................................................... 3-38 

3.7.8 Hydrodynamic and Subcritical Experiments ............................................................ 3-39 

3.7.9 Chemistry and Chemical Engineering ...................................................................... 3-40 

3.7.10 High Explosives and Energetic Science and Engineering ......................................... 3-41 

3.7.11 Materials Science and Engineering .......................................................................... 3-43 

3.8 Weapon Assembly, Storage, Testing, and Disposition Portfolio ............................................ 3-44 

3.8.1 Weapon Assembly, Storage, and Disposition .......................................................... 3-44 

3.8.2 Testing Equipment Design and Fabrication ............................................................. 3-45 

3.8.3 Weapon Component and System Surveillance and Assessment ............................ 3-46 

3.9 Transportation and Security Portfolio ................................................................................... 3-47 

3.9.1 Secure Transportation ............................................................................................. 3-47 

3.9.2 Physical Security ...................................................................................................... 3-49 

3.9.3 Information Technology and Cybersecurity ............................................................ 3-52 

Chapter 4 Infrastructure and Workforce ..........................................................................................4-1 

4.1 Infrastructure ........................................................................................................................... 4-1 

4.1.1 Overall State of DOE/NNSA Physical Assets .............................................................. 4-2 

4.1.2 Major Investments in Programmatic Infrastructure ................................................. 4-2 

4.1.3 Major Investments in Mission-Enabling Infrastructure ............................................. 4-5 

4.2 Workforce ................................................................................................................................ 4-6 
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Chapter 5 Budget and Fiscal Estimates .............................................................................................5-1 

5.1 Future Years Nuclear Security Program Budget ...................................................................... 5-1 

5.1.1 FY 2021 Budget Structure Change ............................................................................. 5-1 

5.1.2 FY 2021 Future Years Nuclear Security Program Request ......................................... 5-2 

5.2 Stockpile Management ............................................................................................................ 5-3 

5.2.1 Budget........................................................................................................................ 5-3 

5.2.2 FY 2021 Budget Request Compared to FY 2020 Enacted Budget .............................. 5-4 

5.2.3 Key Milestones .......................................................................................................... 5-5 

5.3 Production Modernization ....................................................................................................... 5-6 

5.3.1 Budget........................................................................................................................ 5-6 

5.3.2 FY 2021 Budget Request Compared to FY 2020 Enacted Budget .............................. 5-7 

5.3.3 Key Milestones .......................................................................................................... 5-8 

5.4 Stockpile Research, Technology, and Engineering ................................................................. 5-11 

5.4.1 Budget...................................................................................................................... 5-11 

5.4.2 FY 2021 Budget Request Compared to FY 2020 Enacted Budget ............................ 5-12 

5.4.3 Key Milestones ........................................................................................................ 5-14 

5.5 Infrastructure and Operations ............................................................................................... 5-16 

5.5.1 Budget...................................................................................................................... 5-16 

5.5.2 FY 2021 Budget Request Compared to FY 2020 Enacted Budget ............................ 5-16 

5.5.3 Key Milestones ........................................................................................................ 5-18 

5.5.4 Infrastructure Maintenance and Recapitalization Investments .............................. 5-18 

5.6 Other Weapons Activities ...................................................................................................... 5-20 

5.6.1 Budget...................................................................................................................... 5-20 

5.6.2 Secure Transportation Asset ................................................................................... 5-20 

5.6.3 Defense Nuclear Security ........................................................................................ 5-21 

5.6.4 Information Technology and Cybersecurity ............................................................ 5-22 

5.7 Budget Projections Beyond FY 2025 ...................................................................................... 5-24 

5.7.1 Basis for Budget Projections .................................................................................... 5-24 

5.7.2 Sustaining the Current Stockpile ............................................................................. 5-24 

5.7.3 Stockpile Major Modernization ............................................................................... 5-24 

5.7.4 Construction ............................................................................................................ 5-36 

5.8 Affordability Analysis ............................................................................................................. 5-38 

5.8.1 Estimate of Weapons Activities Program Costs and 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 Ongoing Requirements ........................................................................................................... A-1 

A.3 Other Requirements ............................................................................................................. A-11 

A.4 Related Legislation ................................................................................................................ A-12 

Appendix B Exascale Computing Initiative ...................................................................................... B-1 

B.1 Challenges ................................................................................................................................ B-1 

B.2 Approaches and Strategies ...................................................................................................... B-2 

B.3 Collaborative Management ..................................................................................................... B-4 

B.4 Milestones ................................................................................................................................ B-5 

B.5 Conclusion ................................................................................................................................ B-5
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Appendix C: Capabilities and Definitions ........................................................................................ C-1 

Appendix D: Glossary .................................................................................................................... D-1 

Appendix E: Lists of Figures and Tables ........................................................................................... E-1 

Appendix F: Acronyms and Abbreviations ....................................................................................... F-1 
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Legislative Language 

Title 50 of United States Code Section 2523 (50 U.S.C. § 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/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 2021 Stockpile Stewardship and Management Plan (SSMP) is a biennial plan summary 

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

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

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

 

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

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

the nuclear security enterprise had not yet been finalized. 

Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-1 

Chapter 1 

Strategic Context for Managing the 

Nuclear Weapons Stockpile 

The Department of Energy/National Nuclear Security Administration (DOE/NNSA) draws authority for 

managing the Nation’s nuclear stockpile from the Atomic Energy Act of 1954 (42 United States Code 

[U.S.C.] § 2011 et seq.) and more specifically, the National Nuclear Security Administration Act (50 U.S.C. 

§ 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, reducing global nuclear threats, and providing 

nuclear propulsion for Navy submarines and aircraft carriers. 

The 2018 Nuclear Posture Review recognized that the global 

security environment is growing increasingly dangerous and 

uncertain. Countries such as Russia, China, and North Korea 

are investing in efforts to modernize, expand, and diversify 

nuclear arsenals. The United States’ nuclear deterrent is the 

cornerstone of America’s national security strategy and is 

important to maintaining global stability. It is imperative for 

the United States to continue to modernize delivery platforms, 

warheads, and the supporting elements of the nuclear security 

enterprise, to continue to assure friends and allies and deter 

adversaries. 

Every leg of the Nation’s nuclear triad is undergoing 

modernization. DOE/NNSA must synchronize modernized 

warheads with Department of Defense (DoD) weapons delivery 

platform modernization efforts, and this requires a responsive 

and resilient production and scientific infrastructure. 

Modernizing the U.S. nuclear stockpile requires investment in 

three main areas: production capabilities, technical and scientific expertise and tools, and infrastructure. 

DOE/NNSA is the sole provider of most of these critical capabilities. These capabilities cannot be 

outsourced. 

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

 The SSMP documents DOE/NNSA’s plans to maintain the current stockpile, modernize the 

stockpile as needed to respond to evolving deterrent needs, employ science-based stockpile 

stewardship to enhance understanding of the internal nuclear weapons function, maintain and 

modernize the supporting infrastructure, and sustain DOE/NNSA’s highly skilled workforce. 

 The SSMP provides DOE/NNSA’s formal response to multiple statutory reporting requirements, 

which can be found in Appendix A, “Requirements Mapping.” 

This fiscal year (FY) 2021 SSMP serves as the biennial plan summary required by statute. The 25 year 

strategic plan summarized within this report was developed to be in line with the 2018 Nuclear Posture 

Review, the Nuclear Weapons Council’s Strategic Plan for Fiscal Years (FY) 2019–2044, the National 

Key Changes Affecting the FY 2021 SSMP 

x Identification of new Department of 

Defense (DoD) warhead requirements 

x Detailed assessment and mapping of 

warhead and DoD platform and 

synchronization requirements onto 

DOE/NNSA enterprise requirements, 

including production infrastructure 

x Higher-fidelity scope, schedule, and site 

information 

x Improved construction project execution 

and cost information 

x Lessons from ongoing warhead and capital 

equipment acquisition processes 

x Application of continuous improvements 

across the nuclear security enterprise 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-2 

Security Presidential Memorandum (NSPM) – 22, FY 2019 – 2024 Nuclear Weapons Stockpile Plan, and 

other policy directives (see Section 1.1). A detailed assessment and mapping of warhead and DoD 

platform and synchronization requirements onto DOE/NNSA enterprise requirements resulted in a 

number of key changes to the DoD and DOE/NNSA programs of record, as agreed by the Nuclear Weapons 

Council. Key changes affecting the SSMP are summarized in the call-out box. 

The FY 2021 SSMP Biennial Plan Summary includes budget information for the FY 2021 Future Years 

Nuclear Security Program, along with stockpile modernization schedules, preliminary infrastructure 

resource planning, and the long-term DOE/NNSA strategy through FY 2045 to ensure the Nation’s nuclear 

deterrent.1

 The document is structured primarily around the unique capabilities necessary to sustain and 

modernize nuclear weapons, better understand nuclear weapon performance, maintain confidence in the 

aging and evolving stockpile, so that the Nation’s nuclear security enterprise remains responsive and 

resilient. Details of each capability are examined in Chapter 3. 

1.1 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.” 

Several policy documents provide additional direction and guidance to 

DOE/NNSA on accomplishing the nuclear weapons mission. These include 

the 2017 National Security Strategy and DoD’s 2018 Nuclear Posture 

Review and National Defense Strategy. The 2018 Nuclear Posture Review

reinforced the requirement for a nuclear weapons infrastructure that has 

the design, engineering, and manufacturing capabilities necessary to be 

flexible, responsive, and resilient enough to meet changing geopolitical 

challenges. DOE/NNSA performs the nuclear weapons stockpile mission 

in close collaboration with DoD as members of the Nuclear Weapons 

Council. 

Maintaining a safe, secure, and effective nuclear weapons stockpile is one 

of several DOE/NNSA enduring broader missions, which also include 

reducing global nuclear threats and providing the Navy with safe, militarily-effective naval nuclear 

propulsion plants. As laid out in the 2019 National Nuclear Security Administration Strategic Vision

(2019 NNSA Strategic Vision), execution of these overarching missions by DOE/NNSA is built along five 

mission priorities: 

 Maintain the safety, security, and effectiveness of the Nation’s nuclear deterrent 

 Reduce global nuclear security threats and strengthen the nuclear enterprise 

 Provide safe and effective integrated nuclear propulsion systems for the Navy 

 Strengthen key science, technology, and engineering capabilities 

 Modernize the national security infrastructure 

 

1 See 50 U.S.C. § 2453, Future-years nuclear security program, for a detailed description. 

“Nuclear weapons...are the 

foundation of our strategy to 

preserve peace and stability by 

deterring aggression against 

the United States, our allies, 

and our partners.” 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-3 

The first, fourth, and fifth mission priorities for the Nation’s nuclear deterrent are directly supported by 

the plans laid out in subsequent sections. 

1.2 Nuclear Weapons Stockpile Summary 

The size and composition of the nuclear stockpile has evolved as a consequence of the changing global 

security environment and U.S. national security needs. Increasingly diverse and advanced nuclear threats 

and challenges facing the United States continue to put a premium on a U.S. nuclear deterrent that is 

robust, flexible, adaptive, and well-positioned to meet future requirements. 

Maintaining the Nation’s safe, secure, and effective nuclear weapons requires the technical expertise and 

scientific capabilities and resources that reside only within the DOE/NNSA nuclear security enterprise. 

Failure to ensure any of these necessary capability requirements puts the nuclear deterrent at risk. 

Many weapons are well past original design life and require unique capabilities for the effectiveness of 

the stockpile. National level guidance, as defined by NSPM – 22 and the FY 2019 – 2024 Nuclear Weapons 

Stockpile Plan, requires an appropriate number of weapons to support active and strategic hedge 

capabilities, as necessary to meet military requirements. Retired weapons are not included in the count 

of stockpile weapons. Table 1–1 reflects the major characteristics of the Nation’s current nuclear 

weapons stockpile, which consists of two types of submarine-launched ballistic missile warheads, two 

types of intercontinental ballistic missile warheads, several types of bombs, and a cruise missile warhead. 

The classified Annex provides specific technical details by warhead type. 

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

Warheads—Strategic Ballistic Missile Platforms

Type a Description Delivery System Laboratories Mission Military

W78 Reentry vehicle warhead Minuteman III intercontinental 

ballistic missile 

LANL/SNL Surface to 

surface 

Air Force 

W87 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 submarinelaunched ballistic missile LANL/SNL Underwater to 

surface 

Navy 

W88 Reentry body warhead Trident II D5 submarinelaunched ballistic missile LANL/SNL Underwater to 

surface 

Navy 

Bombs—Aircraft Platforms

B61-3/4 Non-strategic bomb F-15, F-16, certified 

NATO aircraft 

LANL/SNL Air to surface Air Force/Select 

NATO forces 

B61-7/11 Strategic bomb B-2 bombers LANL/SNL Air to surface Air Force 

B83-1 Strategic bomb B-2 bombers 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(s) associated 

with the respective weapon. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-4 

1.3 Overall Strategy and Goals of Weapons Activities 

DOE/NNSA is committed to implementing the policy direction provided by the 2018 Nuclear Posture 

Review as managed by the Nuclear Weapons Council. Modernization activities provide nuclear warheads 

that meet DoD performance requirements and DoD and DOE/NNSA safety and security requirements. 

DOE/NNSA maintains the capabilities to perform this critical work as well as the ability to annually assess 

the current stockpile and certify modernized warheads for 

entry into the stockpile without the need for a return to 

explosive nuclear testing. 

Modernization activities address issues such as aging, the 

unavailability of replacement parts, and different weapon 

system flight characteristics due to changes in DoD delivery 

platforms. DOE/NNSA extends the service life of weapons 

that have reached the end of their original design life through 

life extension programs. Other modernization efforts include 

alterations, which do not change the weapon’s operational 

capabilities, as well as modifications, which do change the 

weapon’s operational capabilities. DOE/NNSA also conducts 

surveillances and assessments to confirm that weapons 

currently in the stockpile remain safe, secure, and reliable 

and reports on findings through the annual assessment process. 

DOE/NNSA modernizes and sustains the stockpile through a joint acquisition process for nuclear weapons, 

in partnership with DoD and coordinated through the Nuclear Weapons Council. This acquisition process 

includes the entire life-cycle of the weapon and addresses DoD and DOE/NNSA warhead modernization 

needs from concept assessment to full-scale production to retirement or storage. With five concurrent 

warhead modernization activities underway, DOE/NNSA is implementing an unprecedented variety and 

volume of complex technology development and production work and continues to make progress across 

all five programs. In addition to coordinating weapon modernization and sustainment efforts, DOE/NNSA 

and DoD synchronize nuclear weapon delivery system programs. These coordinated efforts are the basis 

of the Nation’s ability to maintain the nuclear deterrent as the United States faces an increasingly 

uncertain security environment. 

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 national security 

infrastructure: 

 Assess the stockpile annually through science-based stockpile stewardship 

– Assess whether the safety, reliability, and performance of the current and future nuclear 

stockpile can be assured in the absence of underground nuclear testing 

– Renew and develop science capabilities to assess effects of aging, remanufacture, and evolving 

threat environments 

– Maintain a nuclear test capability as a safeguard 

 Extend the life of the nuclear deterrent through modernizations 

– Replace obsolete technology 

– Enhance stockpile safety and security 

– Meet military requirements 

Major Goals of Weapons Activities 

x Ensure that the nuclear weapons 

stockpile continues to meet DoD deterrent 

requirements while enhancing warhead 

safety and security 

x Modernize production capabilities and 

nuclear security enterprise facilities 

x Provide experimental and computational 

capabilities to support annual assessment 

and certification of the stockpile 

x Recruit, train, and retain a highly skilled 

workforce to meet mission deliverables 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-5 

 Assure the capabilities to support the nuclear deterrent in the near and long term (these 

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

Security Enterprise.”) 

– Renew and sustain critical production, manufacturing, and research capabilities 

 Advance innovative experimental platforms, diagnostic equipment, and computational 

capabilities 

– Keep technical expertise and capabilities at the cutting edge to support a responsive and 

resilient enterprise 

 Provide safe and secure transport of nuclear weapons, weapon components, and special nuclear 

materials to meet mission requirements 

1.4 Summary of Key Challenges in Implementing the Stockpile 

Stewardship and Management Plan 

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. DOE/NNSA’s infrastructure has long been 

overdue for the upgrades necessary to create a modern, responsive, and 

resilient nuclear security enterprise that can meet national security missions 

today and into the future. This is particularly critical for the production 

capabilities of the nuclear security enterprise given the recent increased 

scope and requirements. Currently, roughly 30 percent of NNSA’s facilities 

date back to World War II, and more than half are over 40 years old. As 

determined in NNSA’s 2020 Master Asset Plan, more than a third of NNSA’s 

total infrastructure assets (as a percentage of replacement plant value) are 

in poor or very poor condition and are insufficient to meet mission needs. 

These assets include strategic materials facilities critical to the Nation’s 

nuclear deterrent. 

DOE/NNSA must re-establish a number of full-rate production capabilities 

to meet planned DoD warhead deliveries. A number of key facilities do not 

meet modern safety standards and require significantly increased 

investment to maintain. Safety and efficiency remain important concerns 

to be addressed by reinvestments. If any of these facilities experience 

operational shutdowns due to these mounting issues, stockpile 

maintenance and warhead deliveries may be affected. Considering that it can take a decade or more to 

plan and complete facility replacement projects, it is critical to address shortfalls now to assure facility 

availability when needed for mission deliverables and to proactively maintain the existing facilities until 

the replacements are online. 

DOE/NNSA has put in place a plan to renew the essential time-critical manufacturing capabilities 

prioritized to meet DoD near- to intermediate-term warhead deliveries and for workforce safety. This 

plan focuses on five areas: 

 Establishing a production capability of 80 pits per year during 2030 

 Re-establishing high explosive synthesis, formulation, and production capabilities 

“Recapitalizing the nuclear 

weapons complex of 

laboratories and plants is also 

long past due; it is vital we 

ensure the capability to 

design, produce, assess, and 

maintain these weapons for 

as long as they are required.” 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-6 

 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 

replacement of the current lithium production facility 

 Modernizing and enhancing non-nuclear component development and production capabilities 

The next 10 years are critical for modernizing the production capabilities needed for the stockpile. The 

ability to continue delivering life-extended warheads in the future depends on rebuilding the 

infrastructure and capabilities to supply feedstock and warhead materials now. Figure 1–1 shows the 

necessary timeline to meet warhead needs. 

Figure 1–1. Timeline for key infrastructure and capability investments for future warheads2

Failure to meet these timelines may increase the risk to the deterrent and personnel safety, reduce 

operational efficiency, increase operating costs, and hinder recruitment of the workforce. 

Even as the production infrastructure is modernized, DOE/NNSA must continue to rely on an enterprise 

whose buildings’ average age is over 40 years old. Holding the average age of just the highest-priority 

assets constant requires a significant sustained investment. Figure 1–2 shows the projected average age 

of major programmatic facilities over time with planned investments. Without such investments, the 

average age and risk to DOE/NNSA’s mission will continue to increase. 

 

2 DOE/NNSA obtained Critical Decision (CD)-0, Achieve Mission Need, approval for the Power Sources Capability (PSC) facility in 

FY 2019 and for the Energetic Materials Characterization (EMC) facility in FY 2020. DOE/NNSA is working toward CD-4, Approve 

Start of Operations or Project Completion, approval for both projects in FY 2026 based on the clearly defined capability gap and 

mission need. The Analysis of Alternatives process for EMC, Conceptual Design for PSC, and subsequent cost estimates for both 

will inform future budget planning profiles. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-7 

Figure 1–2. Historical average age growth of NNSA major programmatic facilities and 

a projection of the planned stabilization of average age after executing 

the FY 2021 President’s Budget Request-Informed Line-Item Plan 

The condition of the facilities in the nuclear security enterprise imposes a risk to the mission. Accordingly, 

DOE/NNSA is prioritizing strategies to address the infrastructure challenge across the enterprise to assure 

continuity of mission by planning for both recapitalization of the existing infrastructure and the future 

needs of the enterprise. 

While infrastructure is at the forefront of DOE/NNSA’s key challenges, DOE/NNSA is also addressing other 

areas of current and emerging challenges in: 

 The current stockpile program of record represents a continued increase in scope, including 

restarting production operations that have been dormant for decades and increasing overall 

production rates of many components. DOE/NNSA is restoring capabilities and enhancing 

capacity at the production plants to address current stockpile needs and to prepare for future 

uncertainty. 

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

processes, technologies, and tools to produce, qualify, and certify warheads in accordance with 

stringent and evolving stockpile specifications and requirements. The increased number of 

concurrent weapon system builds requires three things: 

– Maturing new options with shortened development cycles 

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

underground 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 1-8 

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

systems, and enhancing production throughput 

 The trustworthiness of the nuclear weapons supply chain must be sustained to protect 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. To assure continued capability, DOE/NNSA is 

installing new tooling, and planning recapitalization efforts to extend the life critical facilities. 

DOE/NNSA is also interacting and collaborating with partners to establish research and 

development efforts that could also serve as a future production capability. 

 The DOE/NNSA nuclear security enterprise has many retirement-eligible employees who are 

expected to leave the workforce in the near future. To prepare for these high numbers of 

retirements, new hiring initiatives are necessary to recruit, train, or retain high-quality individuals 

capable of obtaining security clearances and to provide new personnel with opportunities that 

establish the experience and expert judgment necessary to sustain the stockpile. DOE/NNSA has 

undertaken an enterprise-wide corporate approach to recruiting and retaining the nextgeneration workforce to maintain a world-class workforce now and into the future. 
 Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-1 

Chapter 2 

Managing the Stockpile 

In support of DoD’s highest priority mission – nuclear deterrence – 

DOE/NNSA is responsible for ensuring that U.S. nuclear weapons meet 

military requirements and remain safe, secure, and militarily effective. 

DOE/NNSA stockpile management activities are synchronized with DoD 

sustainment and modernization programs, providing the President with 

flexible deterrence options. 

This chapter describes the manner in which DOE/NNSA accomplishes 

Weapons Activities mission priorities through sustaining, modernizing, 

and dismantling nuclear weapons; maintaining and modernizing 

production operations; and optimizing the scientific tools underpinning 

these efforts. 

Key changes resulted from the identification of new DoD warhead 

requirements and an in-depth assessment and mapping of warhead, DoD 

delivery platform, and synchronization of requirements onto DOE/NNSA enterprise requirements. 

Specifically, these changes include the W93 (a recently established program of record), W80-4, W87-1, 

and modernization of the production infrastructure as needed to improve efficiency and have in place the 

manufacturing operations needed to meet future requirements. Chapter 5 details the major changes in 

the Stockpile Management budget portfolio. 

DOE/NNSA manages the stockpile through four major 

activities: 

 Stockpile Sustainment performs single-system 

and multi-system 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 (Mods), and major alterations (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. This includes modernization programs not possible through an LEP, Alt, or Mod. 

Key Changes Affecting FY 2021 Stockpile 

Management Activities 

x DoD warhead requirements for W93 

x DoD requirements for the W87-1 and W80-4 

x Production infrastructure modernization to 

improve base capabilities to enable weapon 

operations (assembly, disassembly, and 

production) planned for the warhead 

modernization programs, stockpile systems, 

and weapons dismantlement and disposition 

programs to meet delivery requirements 

x Higher fidelity inputs to weapons cost and life 

cycle estimates, based on lessons learned from 

ongoing weapons developments 
 Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-2 

 Weapons Dismantlement and Disposition (WDD)

dismantles retired weapons and disposes of weapon 

components and provides components and materials for 

weapons activities and other DOE/NNSA mission areas.

 Production Operations provides DOE/NNSA with a 

manufacturing-based program that drives individual site 

production base capabilities for warhead modernization 

activities, weapon maintenance, surveillance, weapon 

assembly and disassembly, and weapon reliability and 

safety testing. The scope of Production Operations 

encompasses sustainment of all weapon systems 

capabilities that enable individual weapon production and 

are not specific to one material stream. It works 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, discussed in Chapter 3. 

Managing the stockpile requires comprehensive planning for all 

stockpile elements to fit cohesively into an integrated 

development and production system. This chapter documents all 

of these planning and execution activities; 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. These individual capabilities 

and the linkages to stockpile management are described at length in Chapter 3. Chapter 4 addresses 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 in support of the stockpile mission 

work. 

2.1 Stockpile Sustainment 

Stockpile sustainment activities are responsible for the day-to-day health of the stockpile. These activities 

include surveillance, annual assessments, and routine maintenance to ensure weapons remain safe, 

secure, and reliable over the projected lifecycle. Weapons that remain in the stockpile are eventually 

modernized through modernization programs to address any anomalies and to meet updated safety and 

security standards. These modernization activities (LEPs, Mods, and some major 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 monitored through continuous, multi-layered assessments of the safety, 

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

process evaluates the state of weapons by conducting physics and engineering analyses, experiments, 

surveillance and flight testing, and computer modeling. Assessments may also evaluate the effects of 

aging on performance and quantify performance thresholds, uncertainties, and margins. These 

evaluations rely on all available sources of information, including surveillance, hydrodynamic tests, 

subcritical experiments, materials evaluation, modeling and simulation, and enhanced surveillance 

techniques. These evaluations also involve assembling a body of evidence to assess performance at the 

part, component, subsystem, and system levels to determine whether all of the required performance 

Stockpile Management 

Accomplishments 

(through September 30, 2019) 

x Completed Cycle 23 of the Annual 

Assessment Review process 

x Completed W76-1 last production unit 

x Completed W76-2 first production unit 

x Qualified and sold the first additive 

manufactured component to War 

Reserve production stores 

x Qualified Confined Large Optical 

Scintillator Screen and Imaging 

System (CoLOSSIS II) at the Pantex 

Plant (see Chapter 3, Figure 3–5) 

x Delivered a substantial subset of first 

production units of B61-12 and 

W88 Alt 370 weapon components 

early or on time at the Kansas City 

National Security Campus 
 Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-3 

characteristics are met. The processes are quantitative and combine data and theories with simulations 

of nuclear weapons to arrive at a conclusion that also relies on expert judgment. 

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 each are responsible for. The Commander of the U.S. 

Strategic Command (USSTRATCOM) is also required by statute 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 Stockpile Stewardship Program in the past year. Each annual assessment builds on 

continuing experience with each weapon system and incorporates new information from stockpile 

maintenance, surveillance, experiments, simulations, and other sources to enhance the technical basis of 

each weapon system. 

The assessments and conclusions in the Annual Assessment Reports are peer reviewed 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 that is submitted to the president on an annual 

basis. 

2.1.1.2 Weapon Reliability 

Every September, DOE/NNSA publishes the Weapons Reliability Report, which provides a summary of 

reliability and yield characteristics of all weapons in the stockpile. The report communicates to DoD two 

key contributors to military effectiveness and is the principal DOE/NNSA report on weapon systems 

reliability that USSTRATCOM uses for strategic planning actions and targeting. This report also informs 

the Annual Assessment Review process and incorporates data from 

surveillance activities. 

2.1.1.3 Advanced Certification and Qualification 

Advanced Certification activities improve the methodology and 

physics-based capabilities used to ensure that the evolving stockpile 

will operate as intended. These activities deliver matured 

technologies, diagnostic techniques, data analysis methods, and 

design options for future stockpile needs. Advanced Certification 

activities also preserve and reanalyze legacy nuclear test data and 

conduct simulations of data to benchmark simulation codes. These 

activities enhance DOE/NNSA’s understanding of a weapon’s 

performance and possible failure modes, improve the technical 

components of the quantification of margins and uncertainties 

methodology, and improve the fidelity and agility of certification 

methodologies. 

DOE/NNSA concentrates on stewarding, advancing, and qualifying 

nuclear weapons components, subassemblies, and integrated 

systems to meet military characteristics across the stockpile-totarget sequence environmental requirements (i.e., normal, 

abnormal, and hostile environments specified in the stockpile-totarget sequence). These activities are defined in qualification plans 

Using modeling and simulation, 

Sandia National Laboratories worked 

with Los Alamos National Laboratory 

to provide predictions of B61-12 

nuclear safety timelines used to 

quantify system safety. Thermal 

analysis models were applied by the 

B61-12 project to predict weapon 

nuclear safety for credible accident 

scenarios and weapon configurations 

not considered in qualification testing 

because of schedule and cost 

constraints. The abnormal thermal 

environment qualification and nuclear 

safety arguments were presented by 

systems engineering during B61-12 

system final design review. 
 Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-4 

and use experimental and modeling and simulation capabilities as well as production data to ensure 

system functionality. Experimental capabilities include flight tests, shock and vibration tests, thermal 

environment tests, and exposure to various forms of radiation. Modeling and simulation are used to 

interpolate and extrapolate into regions not addressed by testing and experiments. 

2.1.1.4 Quantification of Margins and Uncertainties 

Assessing weapon performance through predictive capabilities requires the coordination of many 

resources and expertise. Performance is gauged through the quantification of margins and uncertainties 

methodology, which evaluates the degree to which the operation of a weapon is judged to be within the 

bounds of specified operating characteristics. This methodology supports nuclear stockpile decision 

making and enables risk-informed decisions. This methodology’s confidence factor of a prediction is the 

ratio of margin (M) to uncertainty (U), or M/U. Stockpile Research, Technology, and Engineering activities 

(also referred to as Stockpile Stewardship activities) aim to increase the margin when possible and to 

reduce uncertainty by performing R&D in areas such as material properties and improving the fidelity of 

the models used to simulate operation of the warhead. 

2.1.1.5 Responsiveness 

The 2018 Nuclear Posture Review called for rapid implementation of the Stockpile Responsiveness 

Program established by Congress in Section 3112 of the National Defense Authorization Act for Fiscal 

Year 2016 to “effectively respond to emerging threats, unanticipated events, and technological innovation 

through science and engineering” (Senate Report 114-236, Energy and Water Development 

Appropriations Bill, 2017). This program develops and exercises the capabilities required to support all 

phases of the joint nuclear weapons life cycle process, transfers knowledge and skills to the newer 

generation of nuclear weapon designers and engineers, strengthens integration between DoD and 

DOE/NNSA, and uses potential responses to future threats to explore the acceleration of design, 

engineering, testing, production, and qualification methodologies that could increase the responsiveness 

of the enterprise. 

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, and Mods. The surveillance program has six goals: 

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

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

 Determine the margins between design requirements and performance at the component and 

material levels 

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

 Further develop capabilities for predictive assessments of stockpile components and materials 

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

Assessments

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

testing, stockpile laboratory testing, component testing, and material evaluation. DOE/NNSA continually 

refines stockpile evaluation activity planning requirements based on new surveillance information, 
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Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-5 

deployment of new diagnostic tools, annual assessment findings, and analysis of historical information 

using modern assessment methodologies and computational tools. 

2.1.2.1 Anomaly Investigative Process 

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

surveillance data are taken and assessed to determine whether observations are serious enough to open 

an SFI for specific weapon or component issues. SFIs are also opened for anomalies discovered anywhere 

in the stockpile when unexpected phenomena are observed. Such occurrences are investigated by the 

national security laboratory responsible for the anomalous component. Investigations may include 

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

replication (i.e., hydro tests), and subsystem and subcomponent testing. SFIs may remain active through 

several annual assessment cycles. SFIs are closed once an assessment of the impacts to system 

performance or safety is complete and follow-up actions are determined. A tracking and reporting system 

is in place to monitor the progress of an SFI from discovery of the anomaly to submission of the closure 

report, along with the status of any corrective actions. Most SFIs are closed with little to no impact to 

weapon system safety and reliability. 

2.1.3 Maintaining the Stockpile 

Maintaining the current stockpile requires many ongoing activities: 

 LLC exchanges such as gas transfer systems (GTSs), power sources, and neutron generators that 

require periodic replacement to sustain system functionality 

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

maintenance, such as changing the type of LLC, minor repairs and rebuilds, incorporation of surety 

features, and other changes 

 Developing joint test assemblies (JTAs) that represent the original build to the extent possible by 

directly reusing non-nuclear components and substituting surrogate parts for the nuclear 

components 

 Modernizing JTAs to replace sunset technologies and improve the capability to assess stockpile 

performance in the absence of underground nuclear testing 

 Maintaining an Authorization Basis by conducting periodic nuclear explosives safety studies 

 Program management of each stockpile system 

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 lifecycle. 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 and are highly complex, enhance weapon safety and reliability, and must meet stringent 

requirements for proper weapon functionality. 

2.2 Stockpile Major Modernization 

Stockpile Major Modernization activities are achieved through a series of planned LEPs, Mods, and Alts 

that are supported by a strong set of science, technology, and engineering activities. These modernization 
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Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-6 

activities fully reflect on requirements stated in the 2018 Nuclear Posture Review and priorities 

established by the Nuclear Weapons Council. Figure 2–1 displays these plans. 

Figure 2–1. DOE/NNSA warhead activities1

This long-term vision of the stockpile seeks to build 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. Within this strategy, DOE/NNSA will consider flexibility-enabling design 

strategies and an advanced digital enterprise that promotes the 

accomplishment of future system modernization actions with 

greater speed. Incorporating these improvements will enhance 

the Nation’s ability to counter adversaries’ capabilities, 

stockpile aging, and variables associated with supporting U.S. 

hedge capabilities.

To meet requirements for the resilience of the U.S. nuclear 

deterrent, qualification- and certification-ready options for 

materials, components, and systems must be available when 

needed for down-select decisions, development, and 

production. In addition to developing options, the qualification 

and certification pathways for these options must be matured 

ahead of time to be viable for consideration. The activities that 

lead to this state of readiness depend on advanced scientific 

and engineering capabilities that support qualification and 

certification processes and improve the responsiveness of the 

nuclear security enterprise in terms of cycle time and digital 

design tools. Because of the crucial role of science and 

 

1 The SLCM-N first production unit is illustrative and subject to the outcome of the analysis of alternatives process. 

DOE/NNSA Warhead Modernization 

Activities 

DOE/NNSA is currently executing three 

types of warhead modernization activities: 

x An LEP refurbishes warheads of a 

specific weapon type to extend the 

service life of a weapon while increasing 

safety and security. 

x A Mod changes a current weapon type’s 

operational capabilities. It may enhance 

margin against failure, increase safety, 

replace LLCs, etc. 

x An Alt is a material change to a nuclear 

weapon or major assembly that does not 

alter operational capability, but is 

sufficiently important to the user in terms 

of assembly, maintenance, storage, or 

test operations. 
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Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-7 

technology in shaping the future stockpile, the current NNSA Strategic Vision also includes strengthening 

key science, technology, and engineering capabilities among five mission priorities. Technologies and 

capabilities must be developed and continually matured to assure viable technology options for future 

insertion opportunities supporting nuclear weapon modernization programs. 

2.2.1 W76-1 Life Extension Program 

DOE/NNSA successfully completed the last production unit for the W76-1 

LEP in December 2018 and delivered the final warhead to DoD in April 2019. 

Some of these units were converted to meet the requirement for the lowyield W76-2 warhead.

2.2.2 W76-2 Modification Program

The W76-2 is the nation’s response to the low-yield ballistic missile 

requirement called for in the 2018 Nuclear Posture Review. In FY 2020, 

assembly of the W76-2 was completed, with the full quantity produced and 

delivered to the Navy.

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 and to maintain readiness. 

The W88 Alt 370 modernizes the arming, fuzing, and firing subsystem; 

improves surety; replaces the conventional high explosive and associated 

materials; and incorporates a lightning arrestor connector, trainers, flight 

test assemblies, and associated handling gear. The W88 Alt 370 conversion 

is scheduled to run concurrently with LLC exchanges of GTSs and neutron generators. 

2.2.3.1 Status 

The W88 Alt 370 is now in Phase 6.4, Production Engineering, with delivery of the first production unit 

scheduled for the fourth quarter of FY 2021. DOE/NNSA experienced technical issues associated with a 

very limited number of electrical components. DOE/NNSA is coordinating closely with DoD to mitigate 

delays to this weapon program. The program has planned component production rates to work toward 

the original baseline schedule for components not affected by the base metal electrode capacitor issue. 

2.2.3.2 Challenges and Strategies 

Table 2–1 provides a high-level summary of W88 Alt 370 Program challenges and the strategies to address 

each. 

Table 2–1. Summary of W88 Alteration 370 Program challenges and strategies 

Challenges Strategies 

Technology and component manufacturing synchronization 

between DOE/NNSA and DoD partner programs lead to 

shared impacts from any program change or delay.

DOE/NNSA is closely aligned with DoD partners to manage 

production impacts. Collaboration is key for keeping scope, 

schedule, and cost decisions aligned with strategic-level 

priorities. 

Managing baseline system first production unit schedule 

impacts from capacitor component change. 

DOE/NNSA has coordinated with DoD to mitigate impacts. A 

new timeline was coordinated with DoD and endorsed by the 

Nuclear Weapons Council, with a new system first production 

unit scheduled for the fourth quarter of FY 2021. 

“Expanding flexible U.S. 

nuclear options now, to 

include low-yield options, is 

important for the preservation 

of credible deterrence against 

regional aggression. It will 

raise the nuclear threshold 

and help ensure that 

potential adversaries 

perceive no possible 

advantage in limited nuclear 

escalation, making nuclear 

employment less likely.”
 Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 2-8 

2.2.4 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 a 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, -7, and -10 bomb variants. 

2.2.4.1 Status 

The B61-12 LEP is also in Phase 6.4, Production Engineering. Similar to the W88 Alt 370 a lifetime reliability 

concern with base metal electrode capacitors in electrical components necessitated a delay of the B61-12 

first production unit delivery to FY 2022. All -other major components unaffected by the capacitor failures 

are continuing with production and readiness activities. The B61-12 will maintain the initial operational 

capability schedule and the adjusted plan has received concurrence by the Air Force and Nuclear Weapons 

Council. Certification and system qualification activities are ongoing. 

2.2.4.2 Challenges and Strategies 

Table 2–2 provides a high-level summary of B61-12 LEP challenges and the strategies to address each. 

Table 2–2. Summary of B61-12 Life Extension Program challenges and strategies 

Challenges Strategies 

Managing baseline system first production unit schedule 

impacts from capacitor component change. 

DOE/NNSA has coordinated with DoD to mitigate impacts. A 

new timeline was coordinated with DoD and endorsed by the 

Nuclear Weapons Council, with a new system first production 

unit scheduled for the first quarter of FY 2022. 

2.2.5 W80-4 Life Extension Program 

The W80-4 LEP will deploy with the Air Force Long Range Standoff (LRSO) cruise missile. This integrated 

program will replace the aging AGM-86 air-launched cruise missile. The LRSO will improve the Air Force’s 

capability to defeat adversary Integrated Air Defense Systems by improving the bomber force’s delivery 

and survivability capabilities. 

2.2.5.1 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 stockpile-to-target 

sequence 

The W80-4 program office coordinated with DOE/NNSA’s management and operating (M&O) partners to 

develop standardized Earned Value Management practices and schedules across the sites by 

implementing a state-of-the-art software tool to expedite Earned Value Management System data 

analysis. 
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2.2.5.2 Challenges and Strategies 

Table 2–3 provides a high-level summary of W80-4 LEP challenges and the strategies to address each. 

Table 2–3. Summary of W80-4 Life Extension Program challenges and strategies 

Challenges Strategies 

The program faces the challenge of a parallel design 

with the Air Force Long Range Standoff (LRSO) cruise 

missile. 

DOE/NNSA closely aligns W80-4 LEP efforts with those of DoD’s 

LRSO program to refine program goals and define the interface 

scope in detail between the warhead and missile. This collaboration 

enables coordinated cost-informed decisions and interdepartmental 

schedule alignment. 

DOE/NNSA must manage schedule requirements while 

reducing uncertainty.

DOE/NNSA is identifying and implementing opportunities that 

reduce schedule uncertainty and risk; modifying, reducing, or 

eliminating irrelevant requirements; developing a design to 

encompass both warhead and missile environmental requirements; 

and developing processes for increased communication and 

efficiency between design and production agencies. 

2.2.6 W87-1 Modification Program 

DOE/NNSA’s W87-1 Modification Program will replace the aging W78 warhead by modifying the existing 

legacy W87-0 design. Once the B61-12 achieves initial operational capability, the W78 warhead will 

become the oldest weapon system in the stockpile. Critical W78 components continue to age, while the 

military requirements for the safety and security features of W78 warhead have changed since entering 

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 as part of the Ground-Based Strategic Deterrent 

by 2030, as specified in the 2018 Nuclear Posture Review. 

2.2.6.1 Status 

The Nuclear Weapons Council authorized a restart of Phase 6.2, Feasibility Study and Design Options, in 

September 2018. The program is on track to deploy with the Ground-Based Strategic Deterrent by 2030. 

DOE/NNSA 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. In FY 2021, the W87-1 Modification Program is expected to seek Nuclear Weapons Council 

approval to enter Phase 6.3, Development Engineering. 

2.2.6.2 Challenges and Strategies 

Table 2–4 provides a high-level summary of W87-1 Modification Program challenges and the strategies to 

address each.

Table 2–4. Summary of W87-1 Modification Program challenges and strategies 

Challenges Strategies 

Integrating W87-1 Modification Program schedule and 

acquisition efforts with those of the Air Force. 

DOE/NNSA is a member of the Air Force Project Officers Group and 

regularly communicates with the Air Force and related acquisitions 

programs. 

Production is predicated on all newly manufactured 

components. Modernizing nuclear component and 

material manufacturing capabilities requires large, 

multi-year investments. 

DOE/NNSA is supporting commodity and capability programs that 

will provide the materials, components, and capabilities for the 

future stockpile. The W87-1 Modification Program established 

inter-program agreements with applicable commodity and 

capability programs to identify requirements, dependencies, risks 

reporting, and inter-program management strategies. Chapters 3 

and 4 contain more information. 
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Challenges Strategies 

Program success is contingent on development of new 

materials and technologies to address antiquated 

design, material obsolescence, and performance 

expectations, improving life expectancy, reducing 

manufacturing cost and development time, increasing 

safety and security, and improving maintainability. 

The W87-1 Modification Program has established inter-program 

agreements with technology maturation programs to identify 

requirements, dependencies, risk reporting, and inter-program 

management strategies.

The program is incorporating lessons learned from previous LEPs 

and major modernization programs into program plans. 

2.2.7 Sea-Launched Cruise Missile 

DoD is conducting an analysis of alternatives (AoA) study to develop requirements and schedules for the 

Sea-Launched Cruise Missile (SLCM-N). The DoD Office of Cost Analysis and Program Evaluation is serving 

as lead, with DOE/NNSA participating as an observer. The AoA is charged to consider options to support 

a material solution, if required. DOE/NNSA has involved key players in the nuclear security enterprise to 

support the study. 

2.2.8 W93 

The W93 will address future Navy ballistic missile requirements. The W93 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. DOE/NNSA is coordinating with DoD through the 

Nuclear Weapons Council in developing the deterrence strategies as defined in the 2018 Nuclear Posture 

Review. 

2.2.9 Future Warheads 

DOE/NNSA is coordinating with DoD to define the appropriate ballistic missile warheads to support 

threats anticipated in 2030 and beyond, in accordance with the 2018 Nuclear Posture Review. These 

warheads are notional and currently include the future strategic land-based warhead and the future 

strategic sea-based warhead, as well as a replacement air-delivered warhead and submarine-launched 

warhead (for 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 disposal. The dismantlement schedule for retired nuclear 

weapons is planned to provide the material and components required for the stockpile (in particular, LEPs, 

Mods, and Alts). WDD also maintains the proficiency of technicians and balances work scope at the 

production sites. Dismantlement rates are affected by many factors, including appropriated program 

funding, logistics, legislation, weapon system complexity, and the availability of qualified personnel, 

equipment, and facilities. DOE/NNSA’s current five year Dismantlement Plan balances these constraints 

while maintaining strict adherence to legislative guidance. The WDD work scope includes management 

of retired nuclear weapon systems (e.g., managing safety issues), 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. 
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2.3.1.1 Status 

DOE/NNSA continues to make significant progress on dismantling weapons and component disposition. 

WDD is on pace to complete a goal of dismantling weapons that were retired at the end of FY 2008. 

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 of the 

dismantlement line, and sites are eliminating excess component inventories on schedule. 

2.3.1.2 Challenges and Strategies 

Table 2–5 provides a high-level summary of WDD challenges and the strategies to address each.

Table 2–5. Summary of Weapons Dismantlement and Disposition challenges and strategies 

Challenges Strategies 

Meeting WDD requirements within legislative direction 

(National Defense Authorization Act language). 

Use process and cost models to evaluate future dismantlement 

excursions so decision makers can make informed 

dismantlement plans with greatest possible impact. 

Ensuring dismantlement and component disposition plans 

provide sufficient material, components, and canned 

subassemblies (CSAs) for reuse by the warhead 

modernization programs. 

Work closely with all weapon program managers to balance 

material and component needs against future reuse 

possibilities. Develop alternative CSA dismantlement plans that 

provide needed materials while not dismantling CSAs with high 

reuse potential. 

Reducing site legacy inventories of weapon components. Eliminate hazardous items from the legacy inventories first and 

target storage bottlenecks to make adequate space available to 

support warhead modernization program work. 

2.4 Production Operations 

Production Operations activities provide a manufacturing-based 

program that drives individual site production base capabilities for 

warhead modernization activities, weapon maintenance, surveillance, 

weapon assembly and disassembly, and weapon safety and reliability 

testing. It enables individual site capability and capacity to sustain the 

nuclear security enterprise’s production mission, and it encompasses the 

workforce, facilities, and equipment that provide manufacturing and 

capacity across multiple sites. The program’s goal is to maintain the base 

capability required to sustain a responsive and resilient stockpile through 

focused management and production process engineering, 

manufacturing, and production technologies. 

Production Operations also serves as the demand signal for the 

modernization of production capabilities to improve efficiency and 

maintain manufacturing operations that will meet future requirements. 

The program requires close coordination with the Non-Nuclear Component (which provides funding to 

modernize component production) and Advanced Manufacturing Development programs, which are 

charged with development and initial deployment of new or replacement manufacturing and production 

component capabilities. It also heavily depends on required infrastructure modernizations (as discussed 

in Chapter 1, Section 1.4, throughout Chapter 3, and in Chapter 4) to have in place base capabilities with 

adequate capacities, space, and equipment. Production Operations base capability activities also include 

sustaining and improving the capability for calibration and analytical accuracy via certified reference 

material provision to the enterprise and programmatic partners. This activity is vital to process control 

Production Accomplishments 

• Completed over 1,800 critical 

equipment calibrations on time in 

support of production activities 

• Completed approximately 55,000 

analytical tests 

• Upgraded high-resolution 

computed tomography servers 

supporting CoLOSSIS I and II 

(see Chapter 3, Figure 3–5)

• Upgraded vacuum arc remelt 

controller 
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and product certification in Defense Programs as well as partners in Naval Nuclear Propulsion and Defense 

Nuclear Nonproliferation. 

2.4.1 Status 

The Production Operations work scope provides the base capabilities to enable weapon operations 

(assembly, disassembly, and production) planned for the warhead modernization activities, Stockpile 

Systems, and WDD programs to meet delivery requirements. These activities include preventive and 

corrective maintenance, calibrations, quality assurance, supply chain management, logistics, Nuclear 

Enterprise Assurance policy planning meetings, manufacturing execution systems, process flow, and 

scheduling. Model-based enterprise pilot efforts will be funded out of Production Operations through 

FY 2023. 

2.4.1.1 Challenges and Strategies 

Table 2–6 provides a high-level summary of Production Operations challenges and the strategies to 

address each. 

Table 2–6. Summary of Production Operations challenges and strategies 

Challenges Strategies 

Maintaining a knowledgeable and qualified labor force. Work with M&O partners to identify hiring needs and mitigate 

turnover through knowledge capture and next generation work 

force recruitment. 

Difficulty sustaining operations due to decreasing 

reliability of aging capital equipment. 

Categorize and prioritize key production equipment so it can be 

replaced prior to failure. 

Completing infrastructure modernizations that are needed 

for adequate base capabilities, adequate space, and 

equipment capacities. 

Identify infrastructure and space needs and develop 

methodologies to enable prioritization. 

Difficulty in implementing digital transformation of 

product realization.

Determine the cultural, technological, and process-based 

challenges to model-based engineering, provided piloting 

solutions, and generate paths forward through the ModelBased Enterprise Transition Initiative (MBET-I). 

Address evolving Nuclear Enterprise Assurance (NEA) 

requirements. 

Continue integration working groups and NEA Steering Group 

across DOE/NNSA to maintain focus on the highest-priority NEA 

activities implementation at the sites. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 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 DOE/NNSA fulfills the critical mission to 

assess, surveil, modernize, qualify, and certify that the nuclear 

weapons stockpile is safe, secure, and effective. Chapter 3 focuses on 

the Weapons Activities capabilities required to accomplish that 

mission. DOE/NNSA, in partnership with DoD, delivers the capabilities 

required for an effective nuclear deterrent that will provide the 

Nation with the ability to adapt and respond to a dynamic security 

environment, emerging strategic challenges, and geopolitical and 

technological changes. 

The Weapons Activities capabilities described in this chapter directly 

contribute to and support Mission Priority #1, maintaining the safety, 

security, and effectiveness of the Nation’s nuclear deterrent as detailed in the 2018 NNSA Strategic Vision. 

In order to accomplish that mission, DOE/NNSA must: 

 Maintain the safety, security, and reliability of all U.S. nuclear weapons 

 Extend the life of weapons as necessary to assure operational readiness 

 Prepare for the future by ensuring that the nuclear deterrent is modern, robust, flexible, and 

resilient 

 Develop and sustain a highly capable workforce and resilient infrastructure that is responsive to 

future threats 

This chapter describes the elements that define a Weapons Activities capability, and expounds on the 

crucial roles each contribute to maintaining and modernizing the stockpile. The 30-plus Weapons 

Activities capabilities are introduced as a key aspect of the functional portfolios to explain the unique 

nature of the capabilities and to demonstrate the interdependencies in support of the enterprise. Each 

portfolio and associated constituent capabilities is described in detail including the capability health 

status, challenges, and strategies to address those challenges. For an enterprise-level overview of major 

infrastructure investments tied to Weapons Activities capabilities and the supporting workforce, see 

Chapter 4. 

3.1 Weapons Activities Capabilities in Context

Weapons Activities capabilities are vital to the successful conduct of DOE/NNSA’s nuclear deterrence 

mission and comprise the elements illustrated in Figure 3–1. These elements represent the human 

capital, physical assets, resources, and enabling processes underpinning the Weapons Activities 

capabilities. All four elements need to be sustained and modernized to meet current and future missions. 

If any of these elements are missing, the capabilities cannot function as a system. 

Key Changes to Weapons 

Activities Capabilities 

x Reestablishment of weapons 

production capabilities 

x Increase in capacity and 

enhancement of capabilities to 

support weapons requirements 

x Improvements to assessment and 

certification capabilities 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-2 

Figure 3–1. Weapons Activities capability elements 

Weapons Activities capabilities require periodic evaluation across all four elements to assess a capability’s 

health and investment needs. DOE/NNSA must continue to invest in advancing existing capabilities and 

developing emerging capabilities for a strong nuclear deterrent in light of aging or emerging new 

production processes. 

DOE/NNSA is the sole source provider of many functions that comprise Weapons Activities capabilities. 

The highly specialized materials, variability in supply chain component lot sizes, and stringent 

manufacturing specifications required for nuclear weapons production make it difficult or unprofitable 

work for commercial providers. DOE/NNSA must sustain the health of the Weapons Activities capabilities 

for continued availability of these niche functions. In addition, the national security requirements for 

nuclear weapons require trusted domestic vendors for certain materials and processes. 

While Weapons Activities capabilities are nuclear-weapon centric, a number of the capabilities are also 

used to support activities in non-proliferation, naval reactors, and counterterrorism. Examples are 

discussed throughout this chapter. 

3.2 Weapons Activities Capabilities 

More than 30 key Weapons Activities capabilities support the core mission functions, and each capability 

may support multiple parts of the nuclear weapon life cycle. This interdependency between missions and 

capabilities, as well as among the capabilities, is described throughout Chapter 3. These capabilities are 

presented as facets of seven interdependent portfolios, each containing a suite of capabilities that 

together address a particular aspect of Weapons Activities. Figure 3–2 illustrates these capability 

portfolios. The next sections describe the portfolios, their constituent capabilities, specific support to the 

nuclear deterrent mission, and the linkage and integration with other portfolios and capabilities. 
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Figure 3–2. DOE/NNSA Weapons Activities capability portfolios 

3.3 Weapon Material Processing and Manufacturing Portfolio 

The Weapon Material Processing and Manufacturing portfolio 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. Components that contain special nuclear 

material (SNM)1

 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. 

The current stockpile maintenance and modernization programs will continue to demand SNM, high 

explosives (HE) and energetic materials. The nuclear security enterprise must maintain reliable 

production; scientific, technological, and engineering (ST&E) capabilities; integrated infrastructure; and 

logistics (handling, storage, delivery, and supply chain management) for raw materials and War Reserve 

products. Energetic materials are integral to the design and performance of weapon components and 

systems. R&D for energetic materials is covered under Section 3.7.10. 

The capability to handle, package, process, manufacture, and inspect SNM-based products requires the 

support of many specialized facilities and programs 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 that require focused management attention to reliably produce nuclear 

weapon components. The strategies detailed throughout this section for the overall capability are 

organized by the individual materials and supporting programs and address any necessary bridging 

strategy or solution currently being implemented as capability investments for each type of SNM, as well 

as major programmatic infrastructure projects. 

 

1 The Atomic Energy Act of 1954 defines SNM as all isotopes of plutonium, or uranium enriched in the isotopes of uranium-233 

or uranium-235. Tritium is considered a Security Category III nuclear material. 
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Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-4 

3.3.1 Special Nuclear Materials Handling, Packaging, and Processing 

(Plutonium and Uranium) 

3.3.1.1 Plutonium 

The United States must reestablish the capability to manufacture primaries for nuclear weapons, in 

particular plutonium pits to support the W87-1 Modification Program and other planned and future 

weapon modernization programs. As required by statute and as part of a major initiative of the 2018 

Nuclear Posture Review, DOE/NNSA provided Congress with the recommended two site approach to 

produce plutonium pits at a rate of no fewer than 80 pits per year during 2030. Through this two-site 

solution, DOE/NNSA will: 

 Continue to invest in the Los Alamos National Laboratory (LANL) to produce 30 pits per year during 

2026; DOE/NNSA will assess opportunities for LANL to produce above that quantity to help reduce 

schedule risk associated with pit production at the Savannah River Site 

 Repurpose the former Mixed Oxide Fuel Fabrication Facility (MFFF) at the Savannah River Site 

(SRS) as the Savannah River Plutonium Processing Facility (SRPPF) to produce 50 pits per year 

during 2030; 

This two-pronged approach restores a critical production capability central to maintaining the Nation’s 

nuclear deterrent. Operating two geographically separated plutonium pit production facilities provides 

resilience and adaptable options to mitigate against shutdowns, incidents, or other factors that may affect 

operations at a single site. 

The requirement to recapitalize the Nation’s pit production capability and produce no fewer than 80 pits 

per year during 2030 comes from three major factors: 

 DoD and DOE/NNSA requirements to enhance warhead safety and security 

 Risk mitigation against plutonium aging through deliberate, methodical replacement of older 

existing plutonium pits with newly manufactured pits 

 Renewed competition among global powers that may lead to changes in deterrent requirements 

The plutonium capability is also used for radioisotope thermoelectric generator production, pit 

surveillance, plutonium science and aging studies, subcritical experiments, National Aeronautics and 

Space Administration space exploration, and nonproliferation programs. 

3.3.1.1.1 Status 

The Nuclear Weapons Council certified2

 that DOE/NNSA remains on track to: 

 produce no fewer than 80 pits per year during 2030 

 meet the requirements outlined in 50 U.S.C. 2538a 

 meet established milestones and deliverables necessary to produce 30 pits per year at LANL 

by 2026. 

DOE/NNSA is conducting a National Environmental Policy Act (NEPA) review of the recommendation 

described above. The NEPA strategy articulates a three-tiered approach to address pit production 

activities, site-specific environmental impacts, and programmatic actions across the nuclear security 

 

2 Public Law 115-232, § 3120(e) requires the Chair of the Nuclear Weapons Council to annually certify to Congress that the 

DOE/NNSA plutonium pit production plan meets DoD military requirements, and remains on track to achieve all milestones and 

deliverables. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-5 

enterprise. In the first half of FY 2020, the three analysis documents identified as necessary to meet the 

requirements of NEPA were all released for public comment.3, 4, 5 A final Supplement Analysis to the 2008 

LANL Site-Wide Environmental Impact Statement was released in the fourth quarter of FY 2020. 

In addition to dedicated infrastructure efforts at LANL and SRS, DOE/NNSA is recapitalizing existing 

facilities through a series of reinvestment projects, including several line item projects, to replace the 

current aging capability to manufacture and certify pits. 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 (CMR) 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 CMR facility. 

3.3.1.1.1.1 Approach at LANL for 30 Pits Per Year 

DOE/NNSA will establish a reliable capability at LANL to deliver 30 pits per year during 2026. An increase 

in the workforce at LANL is planned over the next few years to accomplish this expanded pit production 

mission, including cost-effective, supporting infrastructure investments for operations support, waste 

management, offices, parking, training, etc. There are several key steps to delivering 30 pits per year 

during 2026: 

 Advance the science and mature the engineering to meet the LLNL design agency specifications 

for plutonium pit production 

 Maintain and update Technical Area 55 (TA-55) Plutonium Facility (PF-4) to ensure reliability and 

continued compliance with all relevant safety requirements 

 Reconfigure TA-55 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 pits per year 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 

 Under the guidance of the Pit Product Realization Team, provide acceptable components and 

support for the experiments and evaluations specified by Lawrence Livermore National 

Laboratory (LLNL) in the Pit Certification Plan 

Plutonium metal purification, casting, machining, and assembly are all currently performed at LANL’s PF-4, 

while the Radiological Laboratory/Utility/Office Building (RLUOB) houses plutonium chemistry operations 

that support plutonium component production, surveillance, and science missions. To accommodate 

increased operations, DOE/NNSA will transition existing operations to be available 24/7 for scheduling 

programmatic work, facility maintenance, equipment installation, and construction activities. 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 Notice of Availability for the Final Supplement Analysis to the Complex Transformation Programmatic Environmental Impact 

Statement, published in the Federal Register January 8, 2020. 4 Notice of Availability of the Final Supplement Analysis of the 2008 Site-Wide Environmental Impact Statement for the Continued 

Operation of Los Alamos National Laboratory for Plutonium Operations, August 2020. 5 Notice of Availability for the Final Environmental Impact Statement for Plutonium Pit Production at the Savannah River Site in 

South Carolina, published in the Federal Register September 30, 2020. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-6 

3.3.1.1.1.2 SRS Approach to Producing a Minimum of 50 Pits Per Year 

DOE/NNSA will reach production of 50 plutonium pits per year during 2030 by repurposing the former 

MFFF as the proposed SRPPF. Preliminary design of the SRPPF and some long-lead procurement of 

equipment will proceed in FY 2021. 

The former MFFF is a Security Category 1/Hazard Category 2 structure that provides an opportunity to 

achieve pit production in a facility designed to meet stringent security and safety requirements for 

plutonium operations. Conceptual design efforts for the proposed SRPPF are underway using knowledge 

gained from LANL, LLNL, and other sites. 

The proposed pit production mission will need a skilled workforce at the site. Early estimates indicate 

that design and construction activities will require approximately 2,000 staff, and manufacturing 50 pits 

per year at SRS will require more than 700 production staff. These early estimates will continue to be 

refined as the project’s design matures. LANL is supporting the training rotation pipeline for the SRS pit 

production mission with subject matter expertise. 

3.3.1.1.1.3 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. Conduct of these activities requires close coordination between the sites to execute the 

disassembly activities, evaluations, experiments, analysis, and recovery. 

DOE/NNSA manages numerous facilities that house plutonium handling, processing, characterization, 

experimental, and storage facilities that must be sustained. A responsive plutonium infrastructure 

requires proper storage facilities, safe and secure disposal pathways, and unique equipment and facilities 

for R&D activities. 

3.3.1.1.2 Challenges and Strategies 

Table 3–1 provides a high-level summary of plutonium capability challenges and the strategies to address 

them. 

Table 3–1. Summary of Plutonium Handling, Packaging, and Processing challenges and strategies 

Challenges Strategies 

Meeting the W87-1 Pit Product Realization Team 

schedule to achieve an enduring production rate of 

30 pits per year at LANL during 2026. 

Continue to invest in LANL plutonium facilities to meet pit production 

milestones – achieving first production unit capability in 2023 then 

achieve an enduring production rate of 30 pits per year during 2026. 

Repurposing of the former Mixed Oxide Fuel 

Fabrication Facility at SRS to achieve a production 

rate of 50 pits per year during 2030. 

Implement a tailored approach to achieve CD-1 (Approve Alternative 

Selection and Cost Range) and CD-2 (Approve Performance Baseline) in 

order to support producing 50 War Reserve pits per year during 2030. 

Meeting warhead modernization program 

requirements timelines, mitigating risk against 

plutonium aging, and responding to changes in the 

deterrent. 

Continue prioritizing recapitalization investments for the pit production 

capability to produce 80 pits per year at LANL and SRS during 2030. 

Use LANL and LLNL subject matter experts to support building 

plutonium production capabilities at SRS. 

Executing environmental 

testing/surety/qualification of plutonium pits 

without nuclear test. 

Use and expand thermal and mechanical testing capabilities to 

evaluate newly manufactured and legacy pits in the STS normal 

environments. Establish equipment and systems to evaluate additional 

normal and abnormal environments that pits could experience. 

CD = Critical Decision 

STS = stockpile-to-target sequence 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-7 

3.3.1.2 Uranium 

Uranium is a strategic national defense asset with different assays and enrichments, including highly 

enriched uranium (HEU), low-enriched uranium (LEU), and depleted uranium. Uranium has a variety of 

defense and nuclear nonproliferation applications, including weapon components and fuel for naval 

reactors, commercial power reactors (tritium production), and commercial and research reactors (medical 

isotopes production). 

3.3.1.2.1 Highly Enriched Uranium 

HEU is uranium in which the concentration of the fissile isotope uranium-235 is increased to 20 percent 

or greater. This capability includes the ability required to recover, recycle, and purify HEU, and then cast 

and machine it into parts that support the current and future stockpile. HEU is required for nuclear 

component production to maintain and modernize the stockpile through warhead modernization 

programs and modifications. HEU is processed into precision components through complex processes 

that must meet stringent requirements. These processes include chemical conversion, special processing, 

casting, machining, assembly, and inspection. The demand for HEU continues to increase based on the 

needs of the stockpile. HEU is recycled from dismantled and disassembled weapon components to 

support production requirements. 

3.3.1.2.1.1 Status 

DOE/NNSA manages and operates the Nation’s primary uranium processing and storage capabilities, as 

well as several laboratories for R&D capabilities, at the Y-12 National Security Complex (Y-12) and other 

locations across the nuclear security enterprise. Much of the infrastructure at Y-12 is deteriorating; some 

of the facilities are more than 70 years old, predating many of the modern safety standards applicable to 

nuclear facilities. DOE/NNSA is decreasing mission dependency on these older facilities by relocating 

certain uranium enrichment processes to existing recapitalized facilities at Y-12, as well as through 

construction of the Uranium Processing Facility. Modernizing the infrastructure that supports this 

capability will improve resiliency and responsiveness for future mission requirements. 

Sustaining uranium processing capabilities requires targeted resources to address mission risk associated 

with aging equipment. Sustainment of capabilities will also require continued training and development 

of subject matter experts to produce components and resolve technical issues. 

HEU processing is required for other missions, including surveillance of the stockpile, fuel for naval 

reactors for submarines and aircraft carriers, and nuclear nonproliferation. Nondestructive and 

destructive testing is performed on HEU components in full assembly and part form as part of critical data 

collection for ensuring confidence in the stockpile. Production of fuel for the Navy requires reprocessing 

HEU into a form that is usable in naval reactors. HEU-related nuclear nonproliferation activities involve 

downblending weapons-grade materials to a lower enrichment level for safe and secure use in domestic 

and foreign nuclear reactors. 

3.3.1.2.1.2 Challenges and Strategies 

Table 3–2 provides a high-level summary of HEU challenges and the strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-8 

Table 3–2. Summary of Highly Enriched Uranium Handling, Packaging, and Processing 

challenges and strategies 

Challenges Strategies

Transitioning enriched uranium capabilities from 70+ 

year-old facilities that do not meet current safety 

standards into existing and new facilities to phase out 

mission dependency. 

Implement the Transition Strategy, which entails complex 

activities to shut down production processes, drain and isolate 

systems, and facilitate post-operations clean-out of the facility. 

Extending the operational lifetime of existing enriched 

uranium processing facilities. 

Sustain existing enriched uranium capabilities through 

enhanced facility and equipment maintenance and the purchase 

of critical spare parts to improve the availability and reliability of 

production systems. 

Constructing the Uranium Processing Facility by the end 

of 2025 to house processes currently performed in older 

facilities that cannot be transferred to another operating 

facility.

Execute capability relocations into existing facilities through the 

Process Technology Development projects. Construct the 

Uranium Processing Facility to provide new floor space for the 

high-hazard, high-security operations currently located in older 

buildings that cannot viably be relocated to existing facilities. 

Prepare for increased work scope by increasing staff in several 

areas, including hiring additional craftspeople to execute the 

construction work.

Maintaining subject matter expertise at the national 

laboratories in base R&D capabilities to support HEU 

production.

Continue two-way communications between the nuclear 

weapon production facilities and the national security 

laboratories to meet increased production needs. Recommend 

improvements that can be applied to HEU production. 

HEU = highly enriched uranium 

3.3.1.2.2 Depleted Uranium 

Depleted uranium, a byproduct of the HEU enrichment process, 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 has a long-term requirement for high-purity depleted uranium metal feedstock to 

meet national security mission needs. 

Depleted uranium is required for nuclear component production to maintain and modernize the stockpile 

through life extension, modification, and limited life component (LLC) exchange programs. Depleted 

uranium is processed into precision components through complex processes that must meet stringent 

requirements. Key processes include casting, rolling, swaging, forming, forging, machining, assembly, and 

inspection. 

Depleted uranium is also required for surveillance of the stockpile. Nondestructive and destructive testing 

is performed for depleted uranium components in full assembly and part forms as part of surveillance 

data collection for ensuring confidence in the stockpile. The demand for depleted uranium continues to 

increase based on the needs of the stockpile. 

3.3.1.2.2.1 Status 

DOE/NNSA’s Manhattan Project-era facilities continue to experience failures that represent significant 

risk to mission delivery and personnel safety. Restarting and sustaining depleted uranium processing 

capabilities requires targeted resources to address risk associated with aging equipment. Sustainment of 

these capabilities also requires continued training and development of subject matter experts to produce 

components and resolve technical issues associated with the complex processes. DOE/NNSA has 

developed an integrated strategy to restore lapsed capabilities; invest in new technologies that simplify 

processes and increase safety and efficiency of depleted uranium operations; and is evaluating 

infrastructure needs to meet mission requirements. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-9 

DOE/NNSA intends to restart and modernize depleted uranium capabilities to meet imminent mission 

requirements, including feedstock procurement, alloying and manufacturing capabilities, and investments 

in key new technologies for maturation. The capability to produce, process, and handle depleted uranium 

supports a number of key missions within the nuclear security enterprise. 

DOE/NNSA has a large quantity of depleted uranium in the form of depleted uranium hexafluoride (DUF6) 

gas, a byproduct of enriching uranium. At present, DOE/NNSA do not have the capability to convert this 

gas to a usable form of depleted uranium. DOE/NNSA began efforts to reestablish depleted uranium 

feedstock capability through material recycle and recovery in FY 2019. As part of that program, 

DOE/NNSA is working with DOE’s Office of Environmental Management to initiate design work for 

construction, installation, and operation of equipment at the Portsmouth DUF6 Conversion Facility to 

meet nuclear stockpile requirements. 

A key element of DOE/NNSA’s depleted uranium strategy is to restart and maintain capabilities for 

depleted uranium and depleted uranium alloying. In order to restart casting, forming, heat-treating, 

machining, and metalworking, DOE/NNSA will need to restart the Vacuum Induction Melt – Vacuum Arc 

Melt production process, as well as establishing capability for machining, training operators, developing 

procedures, and assisting with process qualification activities. 

3.3.1.2.2.2 Challenges and Strategies 

Table 3–3 provides a high-level summary of depleted uranium challenges and the strategies to address 

them. 

Table 3–3. Summary of Depleted Uranium Handling, Packaging, and Processing 

challenges and strategies 

Challenges Strategies

Determining a path forward to mitigate the issue of 

limited supplies of depleted uranium for the future. 

Continue efforts to reestablish the depleted uranium supply. 

Investigate alternate processes and technology improvements that 

can increase the efficiency of traditional manufacturing processes. 

Creating innovative new sources for depleted 

uranium metal production beyond the current 

limited vendor base. 

Increase supply and more closely interface with DoD by exploring 

the capability for recycling depleted uranium resulting from 

processing of byproducts and waste. 

Provide an alternate source for the remainder of the demand. 

Work with DoD counterparts to establish a clear understanding of 

the shared need for this material. 

Achieving and maintaining steady-state production 

of depleted uranium alloy production in existing 

aging equipment and other infrastructure. 

Target resources and address risks associated with aging equipment 

and infrastructure to restart the equipment in a timely manner. 

Meeting stockpile requirements to support warhead 

modernization in the face of potential single-point 

process equipment failures. 

Pursue multiple alternative technologies concurrently. 

Invest in upgrades to recapitalize the aging physical infrastructure 

to reduce risk and the ability to produce strategic materials and 

components. 

3.3.1.2.3 Domestic Uranium Enrichment 

Enriched uranium contains higher concentrations of the fissile uranium-235 isotope than natural uranium. 

Enriched uranium is required at various levels of enrichment and forms for national security and nuclear 

nonproliferation missions, including but not limited to nuclear weapon components and fuel for naval 

reactors, power reactors (tritium production), and research reactors (medical isotope production). 

DOE/NNSA is currently executing an analysis of alternatives (AoA) to determine the best approach to meet 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-10 

the mission need for enriched uranium. The selected option to provide domestic uranium enrichment 

will provide a reliable supply of enriched uranium to support all of the mission needs mentioned above. 

Longstanding policy and international agreements require that LEU used for tritium production be free of 

peaceful use restrictions. The United States currently has no domestic uranium enrichment capability 

that could produce such material. At present, mission needs for enriched uranium are currently fulfilled 

using the United States’ existing HEU stockpile, which is a finite source. To meet future needs, DOE/NNSA 

will require a U.S.-origin enrichment capability for a long-term supply of LEU for tritium production and 

naval nuclear propulsion. 

3.3.1.2.3.1 Status 

DOE/NNSA is executing a three-pronged strategy towards reestablishment of a Domestic Uranium 

Enrichment capability. First, DOE/NNSA is downblending HEU to LEU through 2025, which will extend the 

need date for LEU fuel for tritium production to 2042.6

 Second, DOE/NNSA is preserving and advancing 

enrichment technology by funding centrifuge R&D at Oak Ridge National Laboratory. Third, DOE/NNSA is 

pursuing a capital acquisition to deploy a domestic uranium enrichment capability in time for need. 

The Domestic Uranium Enrichment program formally obtained approval of mission need for 

reestablishment of a domestic uranium enrichment capability, and is currently executing the AoA. The 

AoA will inform NNSA’s strategy to establish a source of unobligated uranium in time for need. Depending 

on the outcome of the AoA, NNSA may need to deploy an enrichment pilot plant in the mid-2020s, which 

will demonstrate the selected enrichment technology at a smaller scale, identify any remaining technical 

issues within sufficient time to develop remedies, and begin training operators ahead of full-scale plant 

operation. The full-scale capability, if selected following the AoA, will be established in time to meet the 

2042 need for tritium production. 

3.3.1.2.3.2 Challenges and Strategies 

Table 3–4 provides a high-level summary of Domestic Uranium Enrichment challenges and the strategies 

to address them. 

Table 3–4. Summary of the Domestic Uranium Enrichment Handling, Packaging, Processing, and 

Manufacturing challenges and strategies 

Challenges Strategies 

Deploying complex enrichment technologies at 

production scale. 

Consider deployment of an enrichment pilot plant, which would 

identify technical issues and further R&D to remedy any issues. 

3.3.2 Tritium Production, Handling, and Processing 

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 and other purposes using tritium-producing 

burnable absorber rods (TPBARs) that are irradiated in the Watts Bar Unit 1 reactor operated by the 

Tennessee Valley Authority (TVA), using unencumbered and unobligated LEU as fuel, i.e., LEU that is free 

of peaceful use restrictions, as discussed in more detail in Section 3.3.1.2.3. Once the TPBARs are 

 

6 In FY 2020, DOE/NNSA’s need date for LEU for tritium production has shifted one year from 2041 to 2042. This is the result of

the program identifying additional quantities of LEU free of peaceful use restrictions within DOE’s inventory. DOE/NNSA has 

executed the necessary contracting actions to secure this material and make it available, providing an additional year of tritium 

production. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-11 

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. 

3.3.2.1 Status 

The demand for tritium is increasing, and DOE/NNSA continues to deliver the requisite supply through the 

use of TVA’s Watts Bar Unit 1 and eventually Watts Bar Unit 2 reactors at TVA. The goal to reach maximum 

tritium production in each of the two Watts Bar reactors by FY 2024 is on schedule. Extraction of tritium 

from irradiated TPBARs at SRS is ongoing and is expected to increase to meet future tritium demand. 

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 maintenance of the facilities as well as 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 of the existing 60-year-old 

manufacturing building that operates 24/7 for GTS production and surveillance. 

Examples of these required smaller projects include: 

 Replacement of large, obsolete distributed control systems for the gas processing equipment 

 Replacement and electronic refurbishment of mass spectrometers to analyze gas associated with 

processing equipment 

 Replacement of the GTS tracking system that is no longer supported by the software vendor 

 Installation of a hydrogen/tritium separation capability in the Tritium Extraction Facility 

 Replacement of the deuterium/tritium separation equipment, including support systems and 

valves 

 Several minor construction projects to address safety, space, and parking requirements 

The scope described above will require significant production downtime. The equipment replacement 

sequence and timing will be critical to ensuring the shortest possible GTS loading outage during 

construction and installation periods. 

3.3.2.2 Challenges and Strategies 

Table 3–5 provides a high-level summary of Tritium Production, Handling, and Processing challenges and 

the strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-12 

Table 3–5. Summary of the Tritium Production, Handling, and Processing challenges and strategies 

Challenges Strategies 

Maintaining a reliable tritium supply chain to meet tritium 

inventory and availability requirements to load GTSs on 

schedule. 

Implement recommendations from the Tritium Sustainment 

Strategic Efficiency Enhancement study to improve supply chain 

reliability, manage facility health and availability, increase 

proficiency and implement process system modernization 

capabilities, procure spare parts or equipment, and evaluate 

options for increasing tritium production. 

Maintaining tritium production in the face of pending 

license renewals in 2055 for The Watts Bar Unit 1 and 2. 

Monitor the results of studies underway regarding potential 

current and emerging replacement methods and technologies 

as risk mitigation for long-term tritium production. 

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.

Developing technologies that further enhance stockpile 

maintenance and evaluation and increase efficiency of 

processes throughout the tritium production life cycle. 

Continue scientific research into the material properties and 

behaviors of TPBARs, GTSs and tritium gas processing 

technologies. Develop a strategy to acquire dedicated 

radiological tritium R&D to address future technology needs 

without compromising mission schedule. 

Planning for long (~2-year) lead times to hire, clear, and 

train personnel. 

Examine multi-year staffing needs appropriate to ensure a 

continuous pipeline of knowledge, skills, and abilities to sustain 

capabilities. 

GTS = gas transfer system 

TPBAR = tritium producing burnable absorber rod

3.3.3 Energetic and Hazardous Material Handling, Packaging, 

Processing, and Manufacturing (High Explosives and Lithium) 

Across the enterprise, DOE/NNSA laboratories and production sites handle energetic and hazardous 

material as a part of the nuclear weapon sustainment and warhead modernization missions. The nuclear 

security enterprise must maintain reliable production, integrated infrastructure, a reliable domestic 

supplier base, and logistics (handling, storage, and delivery) for raw materials and War Reserve products. 

The current stockpile maintenance and modernization programs will continue to demand energetic and 

hazardous materials. Ensuring 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 High Explosives and Energetics Science and Engineering capability 

(Section 3.7.10) for support and is synergistic with its companion capability, special nuclear materials 

handling, packaging, and processing (plutonium and uranium) (Section 3.3.1). 

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 War Reserve 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 as a result of failing infrastructure. Construction of new facilities and recapitalization of 

existing energetic facilities 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 changes to energetic manufacturing. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-13 

3.3.3.1 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 for the proper care and handling of hazardous 

components. Recruitment of skilled professionals and extensive safety training are imperative for safe 

operations. With an increased workload and the attrition/retirement of senior personnel, DOE/NNSA 

must focus on building and training a workforce that can safely perform these operations well into the 

future. 

3.3.3.2 Challenges and Strategies 

Table 3–6 provides a high-level summary of Energetic and Hazardous Materials Handling, Packaging, 

Processing, and Manufacturing (HE and lithium) challenges and the strategies to address them.

Table 3–6. Summary of Energetic and Hazardous Materials Handling, Packaging, Processing, and 

Manufacturing (HE and Lithium) challenges and strategies 

Challenges Strategies 

Maintaining aging equipment and facilities while 

awaiting upgrades or replacements.

Keep aging equipment available for warhead modernization and 

current stockpile systems through rigorous maintenance programs. 

Employ creative methods to mitigate obsolescence issues, such as 

using additive manufacturing to produce parts. 

Maintaining subject matter experts across the nuclear 

enterprise. 

Increase hiring to plan for multi-year training and clearance 

requirements. Transfer knowledge from subject matter experts near 

retirement age to new subject matter experts. Gather and collate 

knowledge from subject matter experts through documentation 

programs targeting critical knowledge areas. 

Maintaining qualified vendors for low-volume, highquality outsourced components.Establish clear requirements for Nuclear Enterprise Assurance. 

When necessary, use in-house capabilities to restore mission 

schedules at risk. 

Continuing operations in aging facilities with 

increasing safety, security, and environmental 

requirements and maintaining them until their 

transition to newly deployed facilities. 

Make short- to medium-term recapitalization investments where 

reasonable. Find creative solutions to maintain facilities past their 

useful life. 

3.3.3.3 High Explosives and Energetics 

HE processing, production, and manufacturing is currently performed both externally by a vendor and 

internally at the Pantex Plant (Pantex). This capability encompasses the ability to supply raw material, 

procure HE from the vendor, and perform safe processing of HE 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. 

DOE/NNSA uses one of two types of HE in the main charge of a nuclear weapon: insensitive high 

explosives can greatly improve the safety and security of the stockpile by reducing the risk of lowlikelihood but high-consequence accidents from initial build through retirement and disassembly. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-14 

3.3.3.3.1 Status 

DOE/NNSA is currently planning two major programmatic line-item construction projects for HE. The HE 

Science and Engineering Facility will consolidate 15 aging facilities into 3 new efficient facilities to conduct 

science, technology, engineering, and production activities in weapons assembly/disassembly and HE. 

The HE Synthesis, Formulation, and Production project will address challenges at the supplier’s 

formulation facility and the difficulty meeting DOE/NNSA production 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. 

Future infrastructure enhancements may include consolidation and modernization of existing facilities 

critical to meet HE R&D capabilities of the stockpile for main charges, boosters, 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).

3.3.3.3.2 Challenges and Strategies 

Table 3–7 provides a high-level summary of High Explosives Handling, Packaging, Processing, and 

Manufacturing challenges and the strategies to address them.

Table 3–7. Summary of the High Explosives Handling, Packaging, Processing, and Manufacturing 

challenges and strategies 

Challenges Strategies 

Developing sufficient supply chain capacity for energetic 

materials in current and future LEPs and Alts. 

Exercise initiatives for Energetic Materials. Refresh HE 

formulation, synthesis, and machining capabilities at Pantex. 

Maintain a robust R&D capability within the national laboratories. 

Maintaining a viable and reliable domestic supplier 

base. 

Exercise suppliers to maintain proficiency on a more frequent 

schedule between procurements and continue technical 

exchanges. 

Ensuring that requirements for energetic materials are 

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. 

Planning for material shortfalls for legacy War Reserve 

HE due to a lack of robust plans and processes to control 

inventories. 

Collaborate with DoD and industrial partners to institute a more 

routine process to exercise synthesis and formulation of energetic 

materials. Preserve and enhance in-house production for items 

such as War Reserve detonator powder production. 

Controlling risks posed by aging HE facilities across the 

nuclear security enterprise needed to support warhead 

modernization and emerging weapons program needs. 

Coordinate with the Infrastructure and Operations Program and 

the Programmatic Recapitalization Working Group to improve 

energetic readiness. Construct the HE Synthesis, Formulation, and 

Production building, the High Explosives Science and Engineering 

Facility, and the Energetic Materials Characterization Facility. 

Forecasting future needs in both legacy inventories and 

new procurements and formulations for HE. 

Charter the NNSA Energetics Coordinating Committee and 

establish an HE sustainment program (both completed). 

HE = high explosives 
Department of Energy/National Nuclear Security Administration | December 2020

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3.3.3.4 Lithium 

Lithium is a subset of the Energetic and Hazardous Material Handling, Packaging, 

Processing, and Manufacturing capability that is key to the nuclear weapon 

production mission. It has recently come into increased focus due to supply, 

production, and infrastructure issues. DOE/NNSA requires specialized, weaponspecific forms of lithium for stockpile sustainment and is the sole source 

provider for these materials. DOE/NNSA manufactures lithium materials into 

precision nuclear weapon components that meet stringent specifications to 

support warhead modernization programs and joint test assembly (JTA) 

requirements, as well as to support TPBAR production for tritium 

modernization. 

3.3.3.4.1 Status 

Lithium is currently provided via a recycling process that relies on retired weapons dismantlement 

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, as well as to other customers through the Strategic Partnership 

Program process. 

DOE/NNSA is actively pursuing alternate, advanced lithium purification 

techniques. In addition, DOE/NNSA established a technology 

development laboratory to support and expand lithium technology 

maturation. Technology Readiness Assessments will be conducted as 

needed to assess the strengths and weaknesses of identified 

technologies. 

DOE/NNSA will continue to work with operating partners to develop 

tailored, long-term staffing plans that anticipate critical skills shortfalls 

within this capability and properly forecast staffing levels based on the 

current program of record. Sustainment of capabilities will require continued training and development 

of subject matter experts to produce lithium components and resolve technical issues associated with 

these complex production processes. 

Currently, aging infrastructure and antiquated equipment present risks to mission delivery that could 

affect the ability to meet stockpile requirements. The current 75-year-old lithium facility has structural 

issues due to chemical contamination that poses safety and environmental concerns and must be 

replaced. To meet near- and long-term requirements, DOE/NNSA put in place a lithium strategy for the 

availability of sufficient lithium processing capabilities (from raw materials to finished assemblies). The 

strategy includes the design and construction of a new Lithium Processing Facility by 2031 to house 

modernized lithium processing capabilities. 

3.3.3.4.2 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 

Hydriding reactor vessels, 

restarted in 2019 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-16 

Table 3–8. Summary of Lithium Handling, Packaging, and Processing challenges and strategies 

Challenges Strategies 

Meeting manufacturing deliverables using existing 

aging and degraded facilities. 

Sustain current operations in the legacy lithium facility to meet 

near-term stockpile needs. 

Monitor and optimize weapons dismantlement schedule to provide 

feedstock as needed. 

Reestablish a small 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 operational. 

Design and construct the Lithium Processing Facility. 

Sustaining lithium production with current inefficient 

processes. 

Develop and mature lithium process technologies to introduce 

efficiencies into the current process and prepare for insertion of 

these new technologies into the Lithium Processing Facility. 

Sustaining the supply of recycled lithium in the face 

of potential shortages from the Weapons 

Dismantlement Program. 

Restart a small purification capability and legacy processing 

capabilities in the legacy lithium facility to provide additional 

feedstock material. 

Deploy a new material recycle cleaning station to provide additional 

capacity. 

Monitor and optimize weapons dismantlement schedule to provide 

feedstock as needed. 

3.3.4 Metal and Organic Material Fabrication, Processing, and 

Manufacturing 

DOE/NNSA uses a variety of metals and organic materials to manufacture precision components that meet 

tight specifications to support life extension, modification, and JTA programs. More detail on this 

capability is provided in the classified Annex. 

3.4 Weapon Component Production Portfolio 

The Weapon Component Production portfolio includes the capabilities for producing all the non-nuclear 

components and systems for weaponization of the nuclear explosive package. These functions are for the 

weapons to arm, fuze, fire, for the designed function when needed. This capability includes both internal 

and external manufacturing and a broad supply base. It also includes identification and verification of 

trusted suppliers to provide materials and parts within the weapon product realization process. 

3.4.1 Non-Nuclear Component Production 

The Non-Nuclear Component Production capability includes activities associated with the design, 

development, qualification, manufacture, assembly, and inspection of all non-nuclear weapon 

components. Many non-nuclear weapon components require special manufacturing and inspection 

protocols. The design, development, qualification, and fabrication of non-nuclear components and 

subsystems used in the stockpile amounts to more than half the cost of each warhead modernization. 

This capability incorporates innovative technologies from both the commercial and government sectors. 

The weapon components include power sources, radiation-hardened microelectronics, neutron 

generators, GTSs, arming, fuzing, and firing (AF&F) assemblies, environmental sensing devices, structural 

parts, cushions, pads, spacers, engineered polymeric components, detonator cable assemblies, and other 

specialized electro-mechanical components. 
Department of Energy/National Nuclear Security Administration | December 2020

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Subject matter experts at the nuclear weapons production facilities work with the national security 

laboratories early in the design phase for producibility of components. The national security laboratories 

define the component testing needed for acceptance through a variety of specialized procedures to 

ensure that (1) materials meet design specifications; (2) parts are manufactured within acceptable 

tolerances; and (3) assemblies function as intended. 

3.4.1.1 Status of Non-Nuclear Component Production 

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 face capacity constraints that affect both production and development of components 

due to increased weapon modernization requirements and scope. As an example, the Kansas City 

National Security Campus (KCNSC) management and operating (M&O) workforce has increased from 

2,200 to more than 4,500 employees since 2014, resulting in a lack of office space, production space, and 

parking. Additional production capacity is being sought through bridging leases at KCNSC, as well as 

shifting production to other DOE/NNSA sites while simultaneously increasing the vendor base for 

commercial component production. DOE/NNSA is considering both short- and long-term solutions as part 

of an ongoing study. 

Sandia National Laboratories (SNL) is the Nation’s sole resource for nuclear weapon power sources 

research, development, testing, and evaluation. Current stockpile stewardship plans are forecasting a 

fourfold increase in workload for power sources production during the next decade. The primary SNL 

power sources research and production facility is a shipping/receiving warehouse converted in 1949. 

Severe degradation of this facility has led to an AoA for a long-term replacement while exploring use of 

other SNL facilities on a temporary basis. Similar issues hold true for radiation-hardened microelectronics 

at SNL’s Microsystems Engineering, Science, and Applications (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 risk to continuity of 

operations. 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 nonnuclear 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 Safety, Infrastructure, 

and Operations, as well full participation from each of the DOE/NNSA sites. 

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 the suite of DOE/NNSA’s 

manufacturing capabilities. Developing additional qualified commercial suppliers will help this effort, 

although a strong economy is creating competition and posing challenges throughout the supplier base. 

3.4.1.2 Challenges and Strategies 

Table 3–9 provides a high-level summary of Non-Nuclear Component Production challenges and the 

strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-18 

Table 3–9. Summary of Non-Nuclear Component Production challenges and strategies

Challenges Strategies

Sustaining unreliable, obsolete equipment and 

inadequately sized and aging facilities, which 

poses risks to manufacture of non-nuclear 

components. 

Plan and execute major investments in facilities, infrastructure, and 

equipment for key production sites.

Optimize Capabilities-Based Investments funding to provide interim 

relief for some of the critical equipment needs related to these key 

product lines. 

Meeting increased weapon program requirements 

on schedule with current production capacity 

limitations across all production sites.

Established the new Non-Nuclear Components program office with 

renewed focus on the design, development, and manufacturing of 

these critical components and funding the associated modernization 

of equipment and facilities to improve production yields and 

capacity, including necessary long-term modernization needs at 

Pantex. 

Develop options for additional space or more efficient use of existing 

space. KCNSC is pursuing an interim solution to lease additional 

manufacturing space and is considering long-term solutions for 

manufacturing needs. DOE/NNSA is conducting an AoA for Power 

Sources.

Gather and use industrial best management practices for application 

across key component production areas. 

Developing domestic external supplier options to 

supplement internal production capacities to meet 

mission requirements and balance R&D needs 

with production. 

Evaluate and develop new suppliers and implement new, moreefficient supplier qualification practices. Use baseline capabilities at 

nuclear security enterprise sites to quickly fulfill unexpected needs 

and expand surge capability. 

AoA = analysis of alternatives 

3.4.2 Weapon Component and Material Process Development 

The Weapon Component and Material Process Development capability is focused on research, 

development, engineering, and integration of 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, the 

maturation of these processes and technologies has been conducted 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 maturation. 

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. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-19 

3.4.2.1 Status of Weapon Component and Material Process Development 

To succeed in reducing costs and increasing agility, DOE/NNSA must achieve more mature technology and 

manufacturing readiness levels prior to insertion of new technologies into weapon systems for the 

modernization programs. 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 potentially adverse effects 

to existing and future programs caused by insufficient facility capacity and emerging production needs, as 

described in Section 3.8.3. 

3.4.2.2 Challenges and Strategies 

Table 3–10 provides a high-level summary of Weapon Component and Material Process Development 

challenges and the strategies to address them.

Table 3–10. Summary of Weapon Component and Material Process Development 

challenges and strategies 

Challenges Strategies 

Conducting rapid design, production, testing, and 

qualification of new equipment and technologies to 

meet modernization needs using inadequate 

processes, capabilities, and facilities. 

Pursue common test capabilities and advanced manufacturing 

technologies and infrastructure for cost-effective, rapid-prototype 

iteration, and faster transition from design to production. Increase 

understanding of properties and performance of additive 

manufacturing materials and components. 

Reducing risks to meeting the mission due to aging 

infrastructure and legacy processes. 

Implement predictive maintenance to determine when failure might 

occur and to prevent the occurrence of the failure; sustaining facilities 

and infrastructure, to include strategies for managing substandard 

facilities that house mission-critical functions or operations. 

Increasing responsiveness and innovation with 

inadequate equipment, facilities, and computational 

capabilities. 

Establish joint projects and milestones between multiple sites, 

programs, suppliers and agencies for early prototyping and technology 

development and maturation and encourage collaboration. 

Dealing with attrition and attendant loss of 

experienced critical personnel needed to bring the 

manufacturing capability up to an appropriate level. 

Provide design staff with the flexibility to develop and implement 

modern concepts by means of advanced manufacturing. Increased 

efforts in training and improved collation and transfer of knowledge. 

3.4.3 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 
Department of Energy/National Nuclear Security Administration | December 2020

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flight tests that will provide evidence that a component can function 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, as well as use technological advances from industry and academia. 

This approach provides weapon designers the opportunities to take prudent risks in advance of use in 

stockpile warheads, facilitates rapid/accelerated cycles of learning, and integrates multidisciplinary, multisite 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 development of innovative weapon technologies. Such activities may include: 

 Developing technology insertion options to prepare the nuclear stockpile for changing global 

security environments, such as design of advanced hardware for nuclear explosive packages, 

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 

3.4.3.1 Status of Weapon Component and System 

Prototyping 

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 both warhead 

performance and manufacturing. Recently, revolutionary 

applications of 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. 

3.4.3.2 Challenges and Strategies 

Table 3–11 provides a high-level summary of Weapon Component 

and System Prototyping challenges and the strategies to address 

them. 

High Operational Tempo Sounding 

Rocket Flight Test (HOT SHOT) 

Launch 

The first HOT SHOT from the Kauai 

Test Facility in Hawaii in May 2018 

supported seven experiments on 

component technologies, additive 

manufacturing processes, model 

validation, and data communications. 

The HOT SHOT program provides an 

agile, risk-tolerant technology 

maturation platform to deepen 

scientific understanding by testing in 

relevant environments at a lower cost 

than operational system flight tests. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-21 

Table 3–11. Summary of Weapon Component and System Prototyping challenges and strategies 

Challenges Strategies 

Improving rapid learning cycles to support evaluation 

of emerging capabilities and reduce risks associated 

with insertion into future systems. 

Employ a high-tempo flight test capability to influence innovative 

design practices for new technologies to gain the necessary flight 

pedigree to mitigate risk in a systems context. 

Using inadequate processes and capabilities for fast 

design, production, testing, and qualification of new 

equipment and technologies to meet modernization 

needs.

Pursue common test methodologies, advanced manufacturing 

technologies, and infrastructure that together support cost-effective, 

rapid-prototype iteration; faster transition from design to production; 

and understanding and assuring the properties and performance of 

additive manufacturing materials and components. 

Conducting prototyping activities with inadequate 

investments in equipment, facilities, and 

computational capabilities. 

Establish joint projects and milestones among multiple sites, 

suppliers, programs, and agencies for support of early prototyping 

and technology development and maturation. This approach will 

facilitate a collaborative scope, joint priorities, integrated systems, 

and leveraging of resources.

Continue development of commercial vendors for component pieceparts for responsive testing and evaluation. 

Dealing with loss of experienced, critical personnel. Increase efforts to provide additional training and improve the 

collation and transfer of knowledge to mitigate the consequences of 

attrition. 

3.4.4 Advanced Manufacturing 

The Advanced Manufacturing capability uses innovative techniques from industry, academia, or 

enterprise-wide 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 

micro-reactors, augmented reality, microwave casting, and electrorefining. 

This capability provides the nuclear security enterprise the ability to respond to emerging issues with the 

current stockpile and adapt new processes for follow-on use to gain production efficiencies. The stockpile 

of the future depends on innovation, agility, and responsiveness in advanced manufacturing in order to 

reduce defects, increase yields, and develop new and improved production techniques for future weapons 

requirements. 

3.4.4.1 Status of Advanced Manufacturing 

All advanced manufacturing technologies require rigorous scientific testing and development to ensure 

the components produced can meet requirements and perform throughout the entire life cycle of the 

weapon systems. To implement this, DOE/NNSA created a long-term Advanced Manufacturing Strategic 

Program Plan linked to 2018 Nuclear Posture Review objectives, the Nuclear Weapons Council strategic 

guidance, and the Technology Development Strategic Plan. 

The themes of this plan are laid out in Figure 3–3 and cover additive manufacturing, automation, 

intelligent production systems, and manufacturing processes to reduce production time, waste, and floor 

space requirements. 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 the development engineering phase of a future weapon program, producing 

confidence in the schedules and cost estimates for those programs. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-22 

Figure 3–3. DOE/NNSA will pursue advanced manufacturing areas for investments across capabilities 

that support a robust and resilient manufacturing capability 

Emerging advanced technology solutions will include an evolving, digital-based enterprise that will use a 

common set of trusted models throughout the entire product life cycle. Benefits include elimination of 

waste and errors, ability to simulate and predict outcomes for critical manufacturing processes, more 

rapid incorporation and propagation of requirements changes, and enhanced producibility, agility, and 

responsiveness. 

The DOE/NNSA sites are working collectively to rapidly advance additive manufacturing technology for 

nuclear deterrence applications. DOE/NNSA has established a multi-site Additive Manufacturing 

Coordinating Team to coordinate activities across the enterprise. Additive manufacturing is an emerging 

technology that requires additional work to apply and qualify additive manufacturing for weapon 

applications. 

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. 

3.4.4.2 Challenges and Strategies 

Table 3–12 provides a high-level summary of Advanced Manufacturing challenges and the strategies to 

address them. 

Table 3–12. Summary of Advanced Manufacturing challenges and strategies 

Challenges Strategies 

Improving responsiveness to assess and qualify new 

manufacturing technologies for the stockpile. 

Continue investments in process and materials R&D, equipment, 

and infrastructure and partner with domestic industrial 

manufacturing to improve collaboration with national security 

laboratories and nuclear weapons production sites. Implement a 

“design for manufacture” philosophy to accelerate the 

qualification process. Include qualification planning as part of 

requirements mapping for technology insertion. 

Achieving faster development of advanced 

manufacturing expertise, equipment, technologies, and 

processes for component certification and qualification. 

Advance the manufacturing development activities at all sites. 

Pursuing more integrated systems across the nuclear 

security enterprise to reduce costs and improve design 

and technology development in the lead-up to 

production. 

Implementation of common, connected platforms for efficient 

design development and definition, effective technology and 

process maturation, common digital model and component 

libraries, and multi-site integrated scheduling. 
Department of Energy/National Nuclear Security Administration | December 2020

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3.5 Weapon Simulation and Computing Portfolio 

The Weapon Simulation and Computing portfolio 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. The Weapon Simulation and Computing portfolio is closely coupled with the Weapon 

Design and Integration portfolio (Section 3.6) and Weapon 

Science and Engineering portfolio (Section 3.7) in an iterative 

fashion, such that capabilities in all three portfolios are 

routinely supporting efforts in the other two. 

Partnership between High Performance Computing and 

Simulation Codes 

High performance computing (HPC) encompasses software, 

hardware, and facilities of sufficient capability and 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. 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. 

Advanced computer 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 portfolio. Codes range 

in application from design of systems to fundamental 

scientific processes. DOE/NNSA codes operate on computers ranging from desktop machines to the 

world’s largest supercomputers. Simulation codes and models must accurately reflect and predict the 

physical phenomena and behaviors of nuclear weapon functionality, ranging from atomistic nuclear 

processes to integrated nuclear performance. These codes must be sufficiently flexible and adaptable to 

run on a variety of the latest HPC platforms. 

Application to the Stockpile 

Together, HPC and simulation codes are important to enabling weapons designers to sustain and certify 

the stockpile in the absence of underground nuclear tests. These capabilities support accelerated nuclear 

weapons design, manufacturing process development, and prediction of weapon response to hostile 

environments. Simulation and HPC play a central role in assessing both the performance and safety of 

the nuclear explosive package and the reliability of the full warhead system in the stockpile-to-target 

sequence (STS) environments. 

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 address issues associated with an 

aging stockpile and modernize the stockpile with new materials in different configurations without a 

strong underground test history. The nuclear security enterprise also relies on these capabilities to 

Sierra, DOE/NNSA’s latest high performance 

computing system, provides computational 

resources that are essential for nuclear 

weapon scientists to fulfill the stockpile 

stewardship mission through simulation in lieu 

of underground testing. DOE/NNSA scientists 

and engineers use the integrated codes on 

Sierra to assess the performance of nuclear 

weapon systems and carry out the advanced 

nuclear weapon science and engineering 

calculations needed to understand key issues 

of weapon physics. In turn, this knowledge in 

turn informs the integrated codes used for 

weapon component design. 
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continue developing methods for quantifying critical margins and uncertainties (see Chapter 2, 

Section 2.1.1). These methods are important for understanding discrepancies between physical 

measurements and simulated data. 

3.5.1 Status of Weapon Simulation and Computing Portfolio 

This portfolio has three major interdependent components (Figure 3–4) that must evolve together to 

support Weapons Activities and other DOE/NNSA missions (codes, computing platforms, and facilities). 

Each component depends on versatile, highly qualified and skilled staff for vital work on and with the 

capabilities in this portfolio. Evolution of these components must be managed in an integrated and 

consistent manner, while balancing program efforts to continuously support current missions and be 

prepared for future requirements. 

Figure 3–4. Interdependent components of the Weapon Modeling and Simulation portfolio 

Simulation codes include integrated design codes (IDCs) that perform large-scale, multi-physics 

simulations in direct support of 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. Improved 

physical models are needed to address response to hostile environments and analyses of manufacturing, 

production, and disassembly processes to reduce cost and waste. Newer generations of IDCs and 

supporting codes are being designed to respond to evolving requirements. Future rewrites to 

accommodate new technologies will be expedited through careful modular design and adaptable 

programming models. 

Just as the science codes support the IDCs, both types of codes are supported by experimental activities 

designed through close cooperation between the simulation and experimental communities. Simulations, 

especially those resolving 3D 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 B for detailed information on the Exascale Computing Initiative). 

HPC platforms are evolving in response to the computer industry’s movement toward increasing 

computing cores on each node or with different processor and accelerator technologies in a system. As 

recently as 2015, IDCs used homogeneous systems with a moderate number of cores. At the time, NNSA 

recognized that these IDCs would run with degraded efficiency on emerging heterogeneous HPC 

platforms. In response, DOE/NNSA initiated development of 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. This work continues in preparation for NNSA’s first exascale system, 

El Capitan, to be deployed at LLNL in FY 2023. DOE/NNSA continues to collaborate with the U.S. HPC 
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technology sector to manage the effect of technological disruptions while delivering productive advances 

in computing for inherent missions. 

DOE/NNSA has a clearly defined strategy of upgrading HPC platforms at regular intervals to meet mission 

need. Evolution of these platforms also creates increased demand on supporting infrastructure. Power, 

cooling, and mechanical requirements have grown dramatically and are being addressed through minor 

construction projects and construction line items. The Exascale Computing Facility Modernization (ECFM) 

project is an example of a construction line item that will upgrade the LLNL computing facility with 

increased power and cooling capability in preparation of the El Capitan system. The nuclear security 

enterprise will continue to manage and coordinate code development and facility upgrades with system 

acquisitions to assure the use of HPC platforms for DOE/NNSA as the technology progresses into the 

exascale era. 

An integrated approach is also 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 portfolio through coordinated evolutions of both codes and platforms. Quantum 

computing, 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. 

3.5.2 Challenges and Strategies 

Table 3–13 provides a high-level summary of Weapon Simulation and Computing portfolio challenges and 

the strategies to address them. 

Table 3–13. Summary of Weapon Simulation and Computing portfolio challenges and strategies 

Challenges Strategies 

Improving the rate at which new modeling and 

simulation capabilities are provided to the Stockpile 

Major Modernization and Stockpile Sustainment 

programs 

Develop and implement a broader range of tools to support rapid 

design, evaluation, and qualification of new materials for a range of 

mission applications while keeping costs manageable.

Enhancing the ability to simulate the effects of 

weapons effects, aging, and manufacturing changes. 

Develop the needed 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 for 

quicker time-to-solution for applications of the above simulation 

enhancements. 

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 more closely with molecular dynamics and 

mesoscale modeling to enhance the utility of these models. 

Develop machine learning techniques that can use these effects 

efficiently for routine use in part scale simulations. 

Working with less effective IDCs that are not 

effectively using advances which have emerged in 

commercial HPC architectures. 

Short-term: Optimize current codes for advanced technology 

hardware.

Longer-term: Evolve HPC tools for a next generation of IDCs to 

achieve new levels of capability through sophisticated programming 

models, software designs, and numerical algorithms. This will 

produce a more responsive simulation capability that is able to 

respond more rapidly to new challenges and more efficiently search 

for possible solutions. 
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Challenges Strategies 

Supporting exascale platforms with inadequately 

structured and sized facilities and supporting 

infrastructure (space, power, and cooling). 

Continue to execute the Advanced Simulation and Computing 

Platform Strategy. Continually survey HPC vendors’ facility 

requirements, identify gaps, and proceed with modernization or 

new infrastructure solutions to meet demands of HPC solutions. 

Aggressively pursue power and cooling efficiencies while building 

on recent programmatic planning and execution successes to 

deliver large-scale power and cooling infrastructure. 

HPC = high performance computing 

IDC = integrated design codes 

3.6 Weapon Design and Integration Portfolio 

The Weapon Design and Integration portfolio 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. The Weapons Design and Integration portfolio is 

closely coupled with the Weapons Science and Engineering and Weapons Modeling and Simulation 

portfolios in an iterative fashion, such that capabilities in all three portfolios are routinely supporting 

efforts in the other two. 

3.6.1 Weapons Physics Design and Analysis 

Design and analysis of 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 concept exploration, conceptual design, requirements satisfaction, 

detailed design and development, production process development, certification, and qualification. It 

also encompasses evaluation of weapon effects. 

Weapons Physics Design and Analysis efforts are predicated on codes developed through the Weapon 

Modeling and Simulation portfolio, as well as the nuclear data and material properties that underpin 

simulation tools. These tools also require data and knowledge acquired through hydrodynamic, 

subcritical, and high energy density (HED) experimental facilities, as well as legacy data from nuclear 

explosive testing, to validate and improve the models. Advances in diagnostics and experimental 

capabilities are required to obtain data of suitably high fidelity. All of these related capabilities underpin 

and are critical for the Weapons Physics Design and Analysis capability. 

3.6.1.1 Status of Weapons Physics Design and Analysis 

The Weapons Physics Design and Analysis capability provides the basic tools and methods necessary to 

design and analyze nuclear explosive packages and determine the state of constituent materials and 

components, as well as 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 that was never demonstrated through 

nuclear explosive testing. The planned warhead modernization requirements over the next decade also 

have expanded. The ability to provide timely analysis to support warhead development timelines is 

critical. 
Department of Energy/National Nuclear Security Administration | December 2020

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DOE/NNSA must develop new, highly capable methods for certifying designs beyond the nuclear explosive 

test history, and the national security laboratories are developing potential non-nuclear experimental 

capabilities and evaluation metrics that can quantify performance without an underground nuclear test. 

3.6.1.2 Challenges and Strategies 

Table 3–14 provides a high-level summary of Weapons Physics Design and Analysis challenges and the 

strategies to address them. 

Table 3–14. Summary of Weapons Physics Design and Analysis challenges and strategies 

Challenges Strategies 

Developing and exercising design (rather than 

assessment) skills in physics, engineering, chemistry, 

and materials science personnel. 

Short-term: Implement activities called out under Stockpile 

Responsiveness in the 2016 National Defense Authorization Act, 

Certification Readiness Exercises, design practicums, and other design 

studies.

Longer-term: Enhance design experience through the 2018 Nuclear 

Posture Review-tasked design studies and Stockpile Responsiveness 

exercises, as well as warhead modernization. 

Developing and exercising certification 

methodologies using recently-developed physics 

performance metrics on device designs for which 

there is no underground test data.

Short-term: Develop metrics and the methodologies for applying 

them.

Longer-term: 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. 

Short-term: Rely on current simulation capabilities (validated by 

aboveground experiments and non-nuclear testing) to model reuse 

design options. 

Longer-term: Develop certification methodologies for reuse and 

replacement designs. Close the capability gap regarding evaluation of 

plutonium response in integrated weapons experiments as part of the 

Enhanced Capabilities for Subcritical Experiments program. 

Mitigating emerging adversary threats to deterrence. Short-term: Rely on current simulation capabilities (validated by 

experiments).

Longer-term: Develop design skills to take advantage of advanced 

manufacturing and testing capabilities. 

Applying machine learning to weapon physics design 

problems for current system confidence, future 

system certification, and increased responsiveness.

Short-term: Develop capabilities to shorten the design loop through 

workflow enhancement and development of surrogate models for 

faster parameter space exploration.

Long-term: 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 

3.6.2 Weapons Engineering Design, Analysis, and Integration 

The Weapons 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 ST&E 

methods so that the integrated solution meets all performance, safety, security, and reliability 

requirements. 

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 
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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. 

3.6.2.1 Status of Weapons Engineering Design, Analysis, and Integration 

While much of the Weapons Engineering Design, Analysis, and Integration capability is being exercised by 

multiple concurrent LEPs, Alts, and stockpile sustainment, some elements are not being adequately 

exercised. Because recent modernization activities have been focused on extending the life of current 

stockpile weapons, there also 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 (50 U.S.C. 2538b) by exercising 

the technical capabilities required for all stages of the design, testing, and production of nuclear weapons, 

as well as 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 Headquarters and site-level 

initiatives to (1) define where specific digital transformation opportunities provide value over time and 

(2) 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. 

3.6.2.2 Challenges and Strategies 

Table 3–15 provides a high-level summary of Weapons Engineering Design, Analysis, and Integration 

challenges and the strategies to address them. 

Table 3–15. Summary of Weapons Engineering Design, Analysis, and Integration 

challenges and strategies 

Challenges Strategies 

Responding in a timely manner to emerging threats 

under current lengthy weapon development cycles. 

Seek ways to accelerate the development cycle, respond more quickly 

to emerging threats, and invest in technology development and 

process improvements to increase the speed at which weapon systems 

are updated and recertified. 

Certifying and qualifying required new processes or 

materials needed for weapon design, engineering, 

and production, especially as weapons design 

moves further away from the underground tested 

design. 

Engage the Material Science and Engineering capability early in the 

design process to inform process development and material choices. 

Perform system trade analyses to develop new materials that can 

support warhead modernization programs. Seek earlier collaboration

with nuclear weapons production facilities in the design process. 

Enabling digital engineering capabilities to reduce 

material and labor waste. 

Develop a high-level understanding of digital engineering challenges 

within the nuclear security enterprise and pilot potential solutions 

through focused efforts (e.g., Production Operations and Product 

Realization Integrated Digital Enterprise) and using potential warhead 

modernization challenges as opportunities. Once acceptable solutions 

are identified, develop information technology infrastructure 

investment requirements and implement policy and process changes 

to allow the official use of digital product definition. 

Ensuring a responsive and resilient nuclear security 

enterprise using aging, Cold War-era facilities that 

need to be refurbished and/or replaced. 

Pursue facility recapitalization, including laboratory space and 

equipment replacements, through a carefully planned, prioritized, and 

executed investment program. 
Department of Energy/National Nuclear Security Administration | December 2020

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3.6.3 Environmental Effects Analysis, Testing, and Engineering 

Sciences 

The Environmental Effects Analysis, Testing, and Engineering Sciences capability uses an array of test 

equipment, tools, and techniques to simulate STS environments and measure the 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, 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. 

3.6.3.1 Status of Environmental Effects Analysis, Testing, and Engineering Sciences 

As the vision for a future stockpile takes shape, current engineering sciences, experimental capabilities, 

and predictive 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. 

Renewed modernization activities and increasing technical requirements have accelerated the need to 

recapitalize and modernize experimental facilities. Many environmental test facilities are aging and 

beyond their projected design life and are in need of 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. As 

an example, DOE/NNSA is currently evaluating options for Combined Radiation Environments for 

Survivability Testing (CREST) through an 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. 

3.6.3.2 Challenges and Strategies 

Table 3–16 provides a high-level summary of Environmental Effects Analysis, Testing, and Engineering 

Sciences challenges and the strategies to address them. 

Table 3–16. Summary of Environmental Effects Analysis, Testing, and Engineering Sciences 

challenges and strategies 

Challenges Strategies 

Conducting higher-tempo testing in aging facilities, 

equipment, and structures that support this capability 

across the DOE/NNSA nuclear security enterprise. 

Higher risk of single-point failures due to breakdown 

of programmatic equipment.

Develop a plan for systematic maintenance, replacement, and 

recapitalization of programmatic capital equipment and test facilities 

to reduce the risk of the unavailability of test capabilities that could 

delay qualification and physics experiments.

Acquiring the capability to experiments in combined 

mechanical, thermal, radiation, and electromagnetic 

radiation environments.

Pursue enhanced combined hostile, normal, and abnormal 

environment testing capabilities to meet evolving and future mission 

requirements. 

Consider building a new reactor facility to address part of the need 

for a combined environment capability. Complete the CREST lineitem construction project.
Department of Energy/National Nuclear Security Administration | December 2020

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3.6.4 Weapons Surety Design, Testing, Analysis, and Manufacturing 

The Weapons Surety Design, Testing, Analysis, and Manufacturing capability includes development, 

analysis, integration, and manufacture of safety and use control systems to prevent accidental nuclear 

detonation and unauthorized use of nuclear weapons, all of which are necessary for a safe and secure 

stockpile. All aspects of this capability require elevated classification control, as well as secure facilities 

and equipment for surety feature design and manufacturing. National requirements from Presidential 

Directives have been implemented through DOE Orders, and new performance-based use control 

requirements were introduced by the Deputy Administrator for Defense Programs to further establish 

high surety standards for the stockpile. 

DOE/NNSA performs assessments that integrate both weapon and venue security and control capabilities 

to understand the best allocation of resources to meet evolving threats. This includes partnerships across 

DOE/NNSA and the Government with stockpile and modernization programs, nuclear counterterrorism 

and incident response personnel, and other national assets. The Integrated Security Architecture Program 

is one example program that incorporates surety technology to meet transportation and shipping 

requirements. 

3.6.4.1 Status of Weapons Surety Design, Testing, Analysis, and Manufacturing 

A variety of surety technologies and approaches have been or are currently under development to 

improve the safety and security of nuclear weapons. Technologies that improve safety and security have 

recently been applied to stockpiled weapons. 

3.6.4.2 Challenges and Strategies 

Table 3–17 provides a high-level summary of Weapons Surety Design, Testing, Analysis, and 

Manufacturing challenges and the strategies to address them. 

Table 3–17. Summary of Weapons Surety Design, Testing, Analysis, and Manufacturing 

challenges and strategies 

Challenges Strategies 

Sustaining technology maturation activities of 

advanced surety technology development. 

Use planned investments in this capability to support the ST&E base 

needed for maturing advanced technologies to increase weapons 

surety and reduce the risk associated with insertion of advanced 

technologies into system LEPs, Mods, and Alts. 

Continuously creating and evolving highly advanced 

surety technologies that are independent of specific 

weapon types or insertion opportunities and can 

result in major surety improvements. 

Establish a balanced program for weapon surety within DOE/NNSA for 

creating and evolving highly advanced, cost-effective surety 

technologies that are independent of specific weapon types and 

minimize effects to warhead performance, safety, and reliability. 

ST&E = science, technology, and engineering 

3.6.5 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 ranging from radiation within the weapon to cosmic rays 

and hostile sources external to the weapon. 

Radiation-hardened microelectronics perform critical sensing and AF&F functions so that 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 
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nuclear deterrent. Production must also keep pace with evolving trends in 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 the Department of Defense. DOE/NNSA is engaged with the 

Strategic Radiation Hardened Electronics Council (SRHEC), including multiple SHREC working groups such 

as the Test and Evaluation, Recruitment and Retention, and Advanced Packaging working groups and is 

the co-lead for the Science and Technology Needs working group. 

3.6.5.1 Status of Radiation-Hardened Microelectronics Design and Manufacturing 

The 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 Microsystems Extended Life Program, which includes equipment upgrades to maintain and advance 

capabilities for all active weapons systems, to include the W87-1 Modification program. 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 post-2040 

capability sustainment. 

3.6.5.2 Challenges and Strategies 

Table 3–18 summarizes the Radiation-Hardened Microelectronics Design and Manufacturing challenges 

and the strategies to address them. 

Table 3–18. Summary of Radiation-Hardened Microelectronics Design and Manufacturing 

challenges and strategies 

Challenges Strategies 

Balancing LEP, Alt, and Mod production requirements 

with development and maturation of new 

engineering- and science-based microelectronics 

capabilities. 

Implement the NNSA Microelectronics Capability Development 

Roadmap, which outlines an agreed-upon 20-year prioritization of 

R&D to be matured in parallel with production. 

Sustaining microelectronics capabilities’ aging 

infrastructure and equipment through upgrades and 

replacements to sustain the existing capability until 

2040.

Incorporate the results of an independent risk assessment, as well as 

an internal evaluation of tools and equipment, into the MESA 

Extended Life Program – a detailed review of maintenance required 

to sustain the status quo R&D and production capability through 2040 

(completed). 

Finding and maintaining trusted U.S. suppliers for 

radiation-hardened microelectronics that meet 

national security requirements. 

Evaluate future options for procuring or producing microelectronics 

that take this difficulty into account. 

3.7 Weapon Science and Engineering Portfolio 

The Weapon Science and Engineering portfolio 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 coupled with 

the Weapon Simulation and Computing portfolio (Section 3.5) and the Weapon Design and Integration 

portfolio (Section 3.6) in an iterative fashion, such that capabilities in all three portfolios are routinely 

supporting efforts in the other two. All three portfolios of capabilities are needed to achieve stockpile 

mission priorities. 
Department of Energy/National Nuclear Security Administration | December 2020

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3.7.1 Nuclear Physics and Engineering 

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 such as fission and 

fusion. 

Measuring nuclear properties relevant to weapons is critical to enhancing predictive capability and 

designing validation experiments that enhance and provide confidence in simulation models. Obtaining 

new measurements and evaluations of nuclear data on weapon properties can reduce uncertainties in 

predictive simulations and to improve reassessments of historic diagnostic data to validate and constrain 

the simulations. Reducing uncertainty is critical to the certification and assessment processes as weapons 

age. 

3.7.1.1 Status of Nuclear Physics and Engineering 

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

and complexity. New detector systems that use new materials are enabling unprecedented data 

precision. Coupling nuclear theory to experiments is also opening up new predictive methods to 

determine nuclear properties for radioactive materials and other properties that are difficult to measure. 

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

with computer codes to improve predictive simulations. Evaluators reconcile newly acquired 

measurements with existing data and physics models to determine “best value” quantities. Presently, the 

United States has a shortage of well-trained evaluators, resulting in a substantial backlog of work. 

Significant investment in training new evaluators is essential to support the nuclear data pipeline in the 

long term. 

3.7.1.2 Challenges and Strategies 

Table 3–19 provides a high-level summary of Nuclear Physics and Engineering challenges and the 

strategies to address them. 

Table 3–19. Summary of Nuclear Physics and Engineering challenges and strategies 

Challenges Strategies 

Maintaining a highly competent workforce in the face of a 

diminishing supply of U.S. trained nuclear theorists and 

evaluators. 

Implement Weapons Activities programs that develop 

workforce skills, knowledge, and abilities, and implement 

strategic alliances and fellowship programs in critical skills 

areas. 

Conducting experiments in aging experimental facilities, 

resulting in increasingly unreliable operations. 

Reduce deferred maintenance and develop conceptual 

plans for future experimental facilities. 

Maintaining reliable operations in facilities where capital 

equipment is becoming difficult to repair or replace due to 

obsolescence. 

Prioritize strategic investments in key equipment. 

Mitigating the negative consequences of merging computer 

architectures on theory, process, and transport software. 

Maintain close coupling with simulation, codes, and HPC 

capabilities to build on investments and efforts in code 

migration to advanced architectures. 

HPC = high performance computing 

3.7.2 Radiochemistry 

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

modern connection to legacy underground nuclear test data. Radiochemical data from the United States’ 

extensive underground nuclear test history database are used to inform modern-day assessments of 
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weapon performance as part of stockpile stewardship. Explosion debris from past tests is analyzed for 

reaction products, and the results are used to benchmark models of events. These data are directly 

integrated into the computer simulations used by the design community; the simulations are modified if 

disagreement is noted between calculated and measured radiochemical reaction products. 

Radiochemistry is also an important element of the diagnostic capabilities used by HED experiments. 

DOE/NNSA is the nuclear forensics7

 lead for the U.S. Government and employs radiochemistry tools to 

address national security problems. 

3.7.2.1 Status of Radiochemistry 

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

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

obtain measurements for evaluation of legacy test data, modern HED experiments, and nuclear data 

collection. 

Many personnel in this specialized field have retired, resulting in knowledge gaps about historical 

methods. Qualified radiochemists must have both 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. 

3.7.2.2 Challenges and Strategies 

Table 3–20 provides a high-level summary of Radiochemistry challenges and the strategies to address 

them. 

Table 3–20. Summary of Radiochemistry challenges and strategies 

Challenges Strategies 

Adequately preserving and cataloguing radiochemical 

data from historical nuclear tests to improve access; 

creating adequately searchable databases that are 

easily accessible across weapon laboratories. 

Scan and catalogue all data and improve function and access of 

data management systems. 

Meeting the high demand for work in aging 

radiochemical facilities. 

Perform incremental initial infrastructure improvements. 

Revitalize radiochemistry facilities and equipment. 

Finding and training enough radiochemists with direct 

nuclear test experience. 

Conduct workshops and other similar mechanisms to facilitate 

knowledge transfer and close gaps caused by the absence of 

ongoing underground nuclear tests. Address the specialized 

knowledge and experimental skill sets required for the modern 

workforce through focused training programs. 

3.7.3 Atomic and Plasma Physics 

Atomic physics is the study of interactions among positively charged atomic nuclei, the surrounding 

negatively charged electrons, and photons, particularly X-rays. Plasma physics is the study of systems 

containing separate ions and electrons that can exhibit collective behavior. Plasmas (highly charged ions 

with complex electronic structure) and X-rays are generated at the extremely high temperatures of 

functioning nuclear weapons and on flagship experimental facilities such as the National Ignition Facility, 

Z pulsed power facility (Z), and Omega Laser Facility. 

 

7 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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3.7.3.1 Status of Atomic and Plasma Physics 

DOE/NNSA’s understanding of atomic and plasma physics is strong at the limits of both 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. 

The workforce of scientists with training in atomic and 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 directly relevant training. 

3.7.3.2 Challenges and Strategies 

Table 3–21 provides a high-level summary of Atomic and Plasma Physics challenges and the strategies to 

address them. 

Table 3–21. Summary of Atomic and Plasma Physics challenges and strategies 

Challenges Strategies 

Addressing uncertainty in the behavior of matter in 

warm and hot regimes, as well as high-magnetic field 

regimes to enhance certainty in simulated outputs. 

Conduct fundamental theoretical and experimental research at 

universities and national laboratories to reduce uncertainties. 

Generating sufficient benchmark data for verification 

of certain phenomena to increase certainty in 

simulated outputs. 

Develop and maintain 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). 

Addressing inconsistency among tabulated data for 

certain properties of materials of interest to increase 

certainty in simulated outputs. 

Extend state-of-the art complex models to produce complete data sets 

and increase model accuracy. 

Increasing availability of computational capacity and 

capability to run complex radiation models. 

Develop new computational tools and exploit new computing 

architectures, leveraging simulation, codes, and HPC capabilities. 

Increasing numbers of atomic and plasma physicists 

trained to work beyond academia and basic research. 

Provide opportunities specific to atomic and plasma physics for 

graduate students; build and maintain academic alliances with 

materials science, plasma physics, and astrophysics departments. 

HPC = high performance computing 

3.7.4 High Energy Density Physics 

High Energy Density Physics includes the study of matter and radiation under extreme conditions (e.g., the 

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

weapon designs and physics models and help evaluate the survivability of weapons in hostile 

environments. Both focused and integrated HED experiments provide the proficiency needed to support 

warhead certification for legacy and new weapon systems. 

HED experiments also support the development of HED physicists and promote the development of skills 

in experimentation, design work, fabrication, instrumentation, and other related areas. 

3.7.4.1 Status of High Energy Density Physics 

Across all three major HED facilities, the experimental platforms have produced data relevant to the 

performance of nuclear weapons. DOE/NNSA has made advances in determining plutonium properties 

at relevant pressures and addressing key questions on aging and remanufacturing using this material. 

These advances provide immediate mission support in predictive nuclear weapon performance and 

survivability assessments, and are crucial to advancing simulation capabilities in energy densities of 

interest. 
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One challenge facing the HED Physics capability is achieving a robust burning plasma, which would 

demonstrate continued progress in shrinking the gap between experimental radiation and weapons 

environments. DOE/NNSA has also set incremental goals toward achieving a burning plasma state8

 at the 

National Ignition Facility. The understanding developed through each stage of experimental performance 

provides key knowledge and constraining data input for simulations, as well as access to material 

properties and outputs unachievable anywhere else in the world. A focused effort on the understanding 

and scaling of all the major inertial confinement fusion (ICF) platforms will establish a foundation for nextstep decisions on investments and program balance needed to realize the long-term goals of the ICF 

program. 

3.7.4.2 Challenges and Strategies 

Table 3–22 provides a high-level summary of High Energy Density Physics challenges and the strategies to 

address them. 

Table 3–22. Summary of High Energy Density Physics challenges and strategies 

Challenges Strategies 

Maintaining world-class experimental 

capabilities in support of high operational 

tempos as facilities age. 

Perform long-term capital planning for facility upgrades and replacements. 

Form a National Diagnostics group to plan and develop transformational, 

high-fidelity diagnostics. Develop advanced experimental platforms and 

predictive capabilities to acquire needed high-fidelity HED data coupled to 

simulations. 

Using HED experimental data to better 

understand evolving hostile environments and 

survivability. 

Develop relevant X-ray, neutron, and gamma sources on NNSA’s HED 

facilities and use these sources to test relevant materials and components. 

Confidently predicting the performance of ICF 

targets to achieve fusion ignition, followed by 

developing a high-yield platform. 

Implement a program of experiments at the HED facilities to characterize 

fusion phenomena; then use the results to enhance predictive modeling 

capabilities. Acquire high-fidelity data and improve physics and modeling 

fidelity to validate 3D models. Investigate models and codes. Understand 

the physics and scaling for the balanced development of next-generation 

capabilities leading to future high-yield platforms. 

HED = high energy density 

ICF = inertial confinement fusion 

3.7.5 Laser and Optical Science, Technology, and Engineering 

Lasers deliver intense beams of energy to localized regions. Within the nuclear security enterprise, these 

laser capabilities are used to generate and probe HED conditions similar to those produced during the 

detonation of a nuclear weapon. Lasers support studies that affect enhancement of design codes, 

qualification of new components and systems, and improvement of weapon performance assessments. 

Experiments on laser facilities directly inform material choices for warhead modernizations and resolve 

stockpile questions. 

Laser-driven devices such as the National Ignition Facility and Omega Laser Facility are complemented by 

pulsed-power machines, generating unique HED conditions with distinct characteristics. The combination 

of capabilities from these two approaches to producing HED conditions work together to cover the 

spectrum of material and physics regimes needed to generate and study the environments produced by 

nuclear weapons upon detonation. 

 

8 A burning plasma—in which at least 50 percent of the energy to drive the fusion reaction is generated internally—is an essential 

step to reach the goal of fusion power generation. (A Strategic Plan for U.S. Burning Plasma Research, National Academies, 201) 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-36 

3.7.5.1 Status of Laser and Optical Science, Technology, and Engineering 

Over the past decade, U.S. laser facilities for HED science have achieved unprecedented levels of 

performance and efficiency. Maintaining and enhancing this capability as equipment and facilities reach 

midlife is a challenge. The National Ignition Facility and other flagship facilities were designed 

approximately 20 years ago, and many subsystems and components are reaching obsolescence and 

becoming increasingly challenging to maintain. Recapitalization of these facilities and equipment with 

minimal pause in operations will be necessary to sustain a key role in maintaining a strong deterrent. 

3.7.5.2 Challenges and Strategies 

Table 3–23 provides a high-level summary of Laser and Optical Science, Technology, and Engineering 

challenges and the strategies to address them. 

Table 3–23. Summary of Laser and Optical Science, Technology, and Engineering 

challenges and strategies 

Challenges Strategies 

Maintaining effective experimental operations and 

mission-required experimental tempos in the face of 

aging and increasingly obsolete subsystems and 

components. 

Develop and implement comprehensive sustainment plans to 

refurbish, recapitalize and incorporate modest enhancements to 

existing facility capabilities. 

Losing U.S. preeminence in laser and optical science, 

which expands the potential for other nations to 

generate materials in extreme conditions beyond 

U.S. capabilities. 

Implement research plans for domestic development of the next 

generation of laser technology, including advanced probe and 

radiography techniques and alternate light sources, to maintain 

U.S. leadership in this discipline. Develop flexible designs for new 

facilities geared toward increased mission capabilities. 

Generating certain experimental conditions using 

current facilities to validate weapons codes for the 

full nuclear weapon life cycle. 

Sustain RDT&E efforts to understand experimental performance gaps 

and implement plans to mitigate identified gaps by extending the 

capabilities of current facilities. 

RDT&E = research, development, test and evaluation 

3.7.6 Accelerator and Pulsed Power Science, Technology, and 

Engineering 

Accelerators use high-voltage pulses to accelerate charged particles to generate high-energy X-rays, 

protons, and/or neutrons that probe objects in weapon-relevant experiments. These pulses of highenergy particles are used as a radiographic source for dynamic imaging diagnostics. 

Pulsed power experiments, which complement laser-driven experiments, provide data on HED materials 

under compression (e.g., densities, temperatures, and radiative properties). Such data are used to study 

aging of components and materials, performance of weapon–relevant materials under hostile 

environments, and survivability of components and systems. 

DOE/NNSA uses accelerator and pulsed power capabilities to support the stockpile in several ways: 

 Generating stockpile-relevant environments to qualify nuclear and non-nuclear materials, 

components, systems, and hardened electronics in hostile environments 

 Providing static and dynamic material information for weapon assemblies and components 

 Generating data to explore and implement new options for the stockpile as external threats 

evolve 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-37 

3.7.6.1 Status of Accelerator and Pulsed Power Science, 

Technology, and Engineering 

Pulsed power technology is vital for laboratory-scale experiments 

at several large-scale facilities such as the Dual-Axis Radiographic 

Hydrodynamic Test (DARHT) Facility, Los Alamos Neutron Science 

Center (LANSCE), High-Energy Radiation Megavolt Electron Source 

(HERMES), Z, and Saturn to generate pressures, temperatures, 

and radiation that approach levels found in nuclear weapons. 

Such experiments produce data to qualify weapon components 

and assess weapon performance, which was formerly only 

possible via underground nuclear tests. At present, the Nation’s 

accelerator and pulsed power facilities are aging and cannot 

provide the full range of test capabilities needed to assure the 

future viability and reliability of the stockpile, including within a 

combination of the environments that weapons may experience 

during use. A new, more capable accelerator is being developed 

for the Enhanced Capabilities for Subcritical Experiments (ECSE) 

project to deliver images of the final implosion stages of 

plutonium; that is not currently possible using existing 

radiography capabilities. Neutron diagnostic capabilities are also 

being developed for deployment in underground subcritical tests. 

3.7.6.2 Challenges and Strategies 

Table 3–24 provides a high-level summary of Accelerator and 

Pulsed Power Science, Technology, and Engineering challenges and the strategies to address them.

Table 3–24. Summary of Accelerator and Pulsed Power Science, Technology, and Engineering

challenges and strategies 

Challenges Strategies 

Generating environments that will validate models 

and simulation capability across the full nuclear 

weapon life cycle. 

Sustain driver and accelerator technology R&D to extend the capability 

of existing facilities and design new facilities to produce higher-fidelity, 

weapons-relevant environments. 

Advancing the capability in pulsed power 

technology to retain the U.S. pre-eminence in 

HED/ICF science and other related technologies. 

Advance the state of the art in fundamental science and technology to 

determine the feasibility of next-generation demonstration systems 

that extend the capabilities of current facilities. Develop feasible, 

practical designs geared to increased outputs and mission capability. 

Providing time-evolution data for experiments of 

interest.

Develop advanced, potentially multiple-pulse technologies that 

support diagnostic techniques that can probe for data at higher spatial 

and temporal resolutions. 

Increasing the reliability and availability of 

experimental facilities and equipment. 

Modernize facilities and equipment. Increase the resilience and 

capability of aging facilities. Use technology advancements developed 

for ECSE in sustaining enduring experimental facilities. 

Recruiting and training the next generation of 

accelerator and pulsed power stewards. 

Make DOE/NNSA facilities available to academic partners for use by 

students and professors; develop small-scale technology 

demonstration systems as platforms to engage and recruit the next 

generation of stockpile stewards. 

ECSE = Enhanced Capabilities for Subcritical Experiments 

HED = high energy density 

ICF = inertial confinement fusion 

Pulsed Power Technology is used to 

simulate the extreme temperatures and 

pressures created by the detonation of 

the nuclear weapon. The Z pulsed 

power facility is the world's most 

powerful and efficient laboratory 

radiation source. It uses high magnetic 

fields associated with high electrical 

currents to produce high temperatures, 

high pressures, and powerful X-rays for 

research in HED science. 

Z is crucial to DOE/NNSA’s mission to 

ensure the reliability and safety of the 

Nation’s nuclear stockpile as it ages. It 

produces key data used to validate 

physics models in computer simulations.
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-38 

3.7.7 Advanced Experimental Diagnostics and Sensors 

The Advanced Experimental Diagnostics and Sensors capability provides detailed measurements of 

materials, objects, and dynamic processes that are critical to weapon performance, other national security 

applications, and HED science. 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 understand scaling of current capabilities to much larger yields. 

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 probe this 

wide range of parameters. 

3.7.7.1 Status of Advanced Experimental Diagnostics and Sensors 

Working across the accelerator/pulsed power science and HED science capabilities, DOE/NNSA has 

developed transformative, next-generation diagnostics for flagship radiographic and HED capabilities. To 

drive down simulation uncertainties, diagnostic measurements and techniques need to be improved to 

obtain higher spatial resolution, additional time resolution/evolution of the data, and improved sensitivity 

at higher energies. 

Several new diagnostic capabilities now contribute to a better understanding of weapon performance and 

the dynamic behavior and response of materials and components in relevant weapon environments. Data 

from experiments that explore the effects of plutonium aging on dynamic material properties are used to 

improve models to inform lifetime assessments of plutonium. 

Recent experiments have been conducted to determine the effects of using additively manufactured 

components that may be added to future warhead modernization programs. With advanced diagnostic 

techniques, uncertainties can be decreased when changes to the stockpile are needed. 

Higher-fidelity measurements lead to a greater understanding of HED and stockpile science. Experimental 

diagnostics push the boundary of what is possible and create concepts for future experimental advances. 

To support this, DOE/NNSA must make investments in three areas: 

 Infrastructure to support the continued health of existing capability in advanced diagnostics 

 Hiring and training the next generation of diagnostic scientists who will push the frontier of 

measurement science 

 Development of advanced and transformational diagnostics 

3.7.7.2 Challenges and Strategies 

Table 3–25 provides a high-level summary of Advanced Experimental Diagnostics and Sensors challenges 

and the strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-39 

Table 3–25. Summary of Advanced Experimental Diagnostics and Sensors challenges and strategies 

Challenges Strategies 

Driving down simulation uncertainties, 

developing better diagnostic measurements and 

techniques, and obtaining higher spatial 

resolution, additional time resolution/evolution 

of the data, and improved sensitivity at higher 

energies.

Provide world-class radiographic and neutron diagnostic systems for ECSE. 

Deliver world-class diagnostic capabilities, including proton radiography at 

LANSCE, X-ray diffraction, and advanced temperature diagnostics. 

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. 

Develop and execute an Integrated Plan for experimental diagnostics. 

ECSE = Enhanced Capabilities for Subcritical Experiments 

ICF = inertial confinement fusion 

LANSCE = Los Alamos Neutron Science Center 

3.7.8 Hydrodynamic and Subcritical Experiments 

The Hydrodynamic and Subcritical Experiments capability provides data on the behavior of imploding 

primaries without creating nuclear yield, providing vital data on material behavior under extreme 

conditions. The combination of hydrodynamic testing with surrogate materials and subcritical 

experiments with plutonium provides the breadth of data needed to build and validate weapon design 

and safety simulation capabilities. 

Hydrodynamic and subcritical experiments are used to characterize nuclear weapon primary performance 

and safety, and can be used to assess the effects of findings from stockpile surveillance. The data are used 

for annual assessment of the stockpile and for 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, as well as effects on weapon performance and potential design 

changes, material substitution, and component changes. 

3.7.8.1 Status of Hydrodynamic and Subcritical Experiments 

The National Hydrodynamic Testing Complex operates as a user facility; it supports base operations while 

the sponsors of individual experiments provide experiment-specific support. This complex is aging, and 

the demand for a higher cadence of experimental data collection required by multiple DOE/NNSA 

programs stresses both the workforce and the specialized facilities that are operating at near capacity. To 

meet a greater demand, additional investments are necessary to maintain the equipment, facilities, and 

people underpinning this capability. 

The weapon programs supported by the Hydrodynamic and Subcritical Experiments capability require 

more and higher-resolution data, which creates the need for both increased testing and enhanced or 

novel diagnostic measurements. Higher-resolution data are needed to validate higher-fidelity, morepredictive computational simulation capabilities used to certify primaries without underground nuclear 

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. 

The U1a Complex Enhancements Project provides the U1a Complex with the infrastructure to house and 

field multi-pulse radiography in support of ECSE. This includes the structures, systems, and components 

necessary for deployment of the ECSE Advanced Sources and Detectors Project’s pulsed X-ray radiography 

equipment and potential future neutron diagnosed subcritical experiments technology that will provide 

valuable data on the phenomena associated with the final stages of a weapon implosion. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-40 

3.7.8.2 Challenges and Strategies 

Table 3–26 provides a high-level summary of Hydrodynamic and Subcritical Experiments challenges and 

the strategies to address them.

Table 3–26. Summary of Hydrodynamic and Subcritical Experiments challenges and strategies 

Challenges Strategies 

Enhance the ability to obtain multi-frame penetrating 

radiographs on hydrodynamic experiments with plutonium pits. 

Implement the ECSE program, which is installing a 

radiographic capability in the U1a Complex to close these 

capability gaps in the mid-2020s. 

Measuring reactivity of subcritical assemblies on the 

experiments. 

Implement neutron diagnosed subcritical experiments in 

the early to mid-2020s to address this need. 

Increasing the physical capacity to generate more experimental 

data from hydrodynamic and subcritical experiments. 

Increase staffing and investments in facility enhancements 

to provide increased experimental capacity and operational 

efficiency. 

Designing and procuring new confinement vessels at all firing 

facilities as existing vessels exceed useful life. 

Establish an enduring vessel capability and procurement 

funding strategy with the intention to reestablish a 

domestic fabrication and manufacturing capability for 

vessels. 

Dealing with increased operational issues due to aging 

infrastructure at firing sites, as well as at upstream and 

downstream support facilities. 

Invest in baseline capability (facilities, infrastructure, and 

equipment) to sustain and enhance the hydrodynamic 

capabilities at firing sites. 

ECSE = Enhanced Capabilities for Subcritical Experiments 

3.7.9 Chemistry and Chemical Engineering 

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. 

Chemistry and chemical engineering are essential for synthesizing, purifying, processing, and fabricating 

all of the materials that are currently fielded in stockpile warheads, proposed for near-term warhead 

modernizations, or to be deployed to meet future system requirements. Chemical knowledge and 

assessment are key to ensuring quality, performance, and safety of the current stockpile. 

Chemistry and Chemical Engineering plays a key role in the design and improvement of manufacturing 

processes for weapon components, as well as in resolving stockpile production and surveillance issues 

and developing and qualifying new materials and diagnostics. Chemistry supports materials and 

compatibility testing to mitigate material aging, while computational chemistry and material science tools 

help to understand the chemical reactions that control material creation and the mechanisms and effects 

of aging and degradation. 

3.7.9.1 Status of Chemistry and Chemical Engineering 

The breadth of the current capability is extensive and presents challenges in maintaining an expert 

workforce and sustaining modern facilities. Developing a sustainable workforce requires active partnering 

with academic institutions and onboarding that allows significant training time in specialized areas. Some 

facilities have received major capital investments; e.g., the Plutonium Facility upgrades, the new Uranium 

Processing Facility, and renovated radiological space to replace the existing facilities. Future investments 

are needed for modernized laboratory space to house radiological and general chemical synthesis. 

3.7.9.2 Challenges and Strategies 

Table 3–27 provides a high-level summary of Chemistry and Chemical Engineering challenges and the 

strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-41 

Table 3–27. Summary of Chemistry and Chemical Engineering challenges and strategies 

Challenges Strategies 

Predicting chemical compatibility in new systems to 

reduce the need for expensive core-stack and shelf life 

units. 

Develop validated computational chemistry models that span 

length and time scales and address reactivity at interfaces. 

Eliminating capability gaps in weapons analytical 

chemistry as DOE/NNSA increases pit production 

activities. 

Simultaneously execute War Reserve qualification of analytical 

techniques and the Chemistry and Metallurgy Research facility 

exit strategy. 

Scaling up of new material formulations from the 

laboratory to industry to provide commercial material 

sources of required materials. 

Partner across the nuclear security enterprise to transition from 

large numbers of small-scale experiments to fewer informed 

pilot-scale tests. 

Improving the ability to predict the effects of age on 

components. 

Advance multiscale, validated predictive models of material 

aging, including the kinetic and thermodynamically aware 

degradation models of organics, inorganics, energetics, and 

corrosion of metals.

Improve the use of data informatics and artificial intelligence to 

aid the interpretation of large data sets (e.g., mass spectrum 

data from compatibility and surveillance testing). 

Develop and deploy nondestructive tools to assess the state of 

materials in service. 

Understanding the effects of processing conditions on 

production consistency and device performance.

Provide advanced inline analytical and diagnostic tools combined 

with process modeling to introduce efficiencies in 

manufacturing. 

Developing validated predictive models of material aging 

that incorporate material microstructure, including 

degradation of organics and energetics and corrosion of 

metals. 

Improve the use of data informatics and artificial intelligence to 

aid the interpretation of large data sets (e.g., mass spectrum 

data from compatibility and surveillance testing) and incorporate 

reaction kinetics. 

Improving flexibility in the current and future stockpile 

through accelerated qualification methodologies using 

advanced and additive manufacturing techniques. 

Synthesize new formulations that expand material possibilities 

for the design of new composite, multifunctional materials. 

Build confidence in a prediction capability of the stability over 

time of materials made by new processes. 

Successfully collaborate with design and production agencies to 

design for manufacturing. 

Improving throughput, reducing waste, and limiting 

worker exposure to hazards. 

Explore improvements in automated synthesis, advanced 

shielding, and compatibility testing and prediction for waste 

streams. 

Conducting activities in aging chemistry infrastructure. Modernize chemistry facilities across the nuclear security 

enterprise to support analytical and physical chemistry, as well 

as new feedstock synthesis and process scale-up needs, including 

radiological space. 

Developing and maintaining a pipeline of specialized 

chemists and chemical engineers required to meet 

current and future staffing needs. 

Develop a hiring pipeline by forming strategic alliances with 

specific universities that are strong in areas that are relevant to

the nuclear security enterprise. 

3.7.10 High Explosives and Energetic Science and Engineering 

The High Explosives and Energetic Science and Engineering capability encompasses the study of 

detonation and deflagration physics, shock wave propagation, and reaction initiation. It includes the 

design, synthesis, formulation, manufacturability, inspection, testing and evaluation of HE and other 

energetic materials and components for specific applications. Knowledge of the characteristics and 

behavior of energetic materials is necessary to understand nuclear weapon performance and can 

contribute more-efficient weapons design and production. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-42 

DOE/NNSA mission priorities are critical for making available energetic materials and products to meet 

production base and capability objectives and other commitments. DOE/NNSA organizes energetic 

materials efforts to meet weapon delivery schedules and address challenges through strategic planning. 

The energetic materials mission covers three broad areas: 

 Surveillance, maintenance, and LLC replacement of existing stockpile material 

 Development of new materials for modernization 

 R&D, diagnostics, and safety studies of novel materials and processes 

3.7.10.1 Status of High Explosives and Energetic Science and Engineering 

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. To 

that end, DOE/NNSA has a project underway for energetic materials characterization, and plans to 

recapitalize additional HE facilities, including the High Explosives Applications Facility, Site 300, and the 

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

3.7.10.2 Challenges and Strategies 

Table 3–28 provides a high-level summary of High Explosives and Energetic Science and Engineering 

challenges and the strategies to address them. 

Table 3–28. Summary of High Explosives and Energetic Science and Engineering 

challenges and strategies 

Challenges Strategies 

Supporting science and engineering programs and 

responding to emerging weapons program needs in aging HE 

facilities. 

Develop and implement plans for modernization of 

HE/energetic materials design infrastructure to meet 

immediate programmatic needs, while maintaining the 

technological capacity to support the long-term HE mission. 

Coordinate with the Infrastructure and Operations Program 

and the Programmatic Recapitalization Working Group to 

improve energetic capability readiness. Implement the 

Energetic Materials Characterization Facility. 

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 in conjunction with goals reflecting future program 

requirements. 

Developing the next generation of HE scientists and 

engineers to continue to maintain the stockpile into the 

future. 

Develop training and knowledge transfer programs to retain 

current HE scientists and engineers; develop partnerships 

with key universities to increase available pool of candidates. 

Improving HE safety by bringing the state of the prediction 

capability in line with HE performance prediction. 

Understand and predict HE deflagration through a 

combination of bench- and full-scale experimentation. 

Finding a sufficient number of competent, qualified 

commercial vendors that are willing and able to meet 

stringent specifications and produce a diversity of energetic 

materials for commercial vendors to improve existing 

processes. 

Collaborate with DoD and industrial partners to produce HE 

and preserve in-house production authority, such as for War 

Reserve detonator powder production. 

HE = high explosives 
Department of Energy/National Nuclear Security Administration | December 2020

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3.7.11 Materials Science and Engineering 

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 the 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). 

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

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

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

developed for insertion into the stockpile and are integral to extending the life of weapon systems. This 

reduces risks and may improve the overall safety and reliability of the stockpile. Dynamic material studies 

investigate the structural transformations, deformation, fracture, and chemical reactions that contribute 

to a confident prediction of weapon performance. 

3.7.11.1 Status of Materials Science and Engineering 

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 partnerships among DOE/NNSA 

national security laboratories and nuclear weapons production facilities, sites with experimental 

platforms, and networks with strategic academic partners. 

DOE/NNSA performs thousands of materials science and engineering experiments using a broad range of 

R&D, testing, and evaluation facilities. Capabilities for probing material properties in extreme conditions 

have been advanced by using light sources and HED physics facilities. However, a number of new 

materials and increased scrutiny of how legacy materials change with age are putting significant strain on 

throughput at existing facilities. 

3.7.11.2 Challenges and Strategies 

Table 3–29 provides a high-level summary of Materials Science and Engineering challenges and the 

strategies to address them. 

Table 3–29. Summary of Materials Science and Engineering challenges and strategies 

Challenges Strategies 

Maintaining and enhancing the ability to assess 

material changes due to aging, obsolescence, 

replacement for hazard mitigation in a timely and 

cost-effective manner for qualification. 

Develop 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. Expand experimental and computational abilities to 

study these material changes through partnerships between 

national security laboratories and nuclear weapons production 

facilities and deliver solutions to emerging materials issues. 

Maintaining capabilities to develop new materials and 

perform advanced evaluation and assessment of 

materials behavior in aging facilities, using aging 

equipment, in support of development, design, 

production, and surveillance activities. 

Execute capital reinvestment in key facilities and equipment for 

Materials Science and Engineering capabilities to support nuclear 

weapons throughout life cycles. 

Maintaining a reliable, sustainable and predictable 

material supply chain for nuclear weapons 

components. 

Develop strategic partnerships with U.S. industries to understand 

the effects of material process or property changes on performance. 

Maintaining the ability to perform rapid design and 

qualification of replacement materials in the face of 

the loss of vendor supply. 

Understand the key material parameters affecting the performance 

of legacy materials and control them in the production of 

replacements materials. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-44 

Challenges Strategies 

Performing rapid design and qualification of new 

materials needed to meet future requirements. 

Use advanced manufacturing techniques to design new materials 

with controlled and tailored performance. 

Establishing a capability to quantify mesoscalea

material performance and micron-scale performance 

in bulk materials in dynamic environments. 

Develop new experimental techniques to dynamically probe bulkmaterial performance in the mesoscale regime. Use existing 

experimental platforms and explore the benefits and opportunities 

of developing new platforms. 

Meeting the high demand for dynamic materials 

properties data to support warhead modernizations 

and Science programs and in situ diagnostics. 

Develop and implement modern and cutting-edge material science 

and engineering tools that will attract the next generation of nuclear 

security enterprise workforce. Build and sustain pipeline networks 

with U.S. academic institutes. Use cross-functional teams of experts 

to prioritize the use of unique capabilities such as plutonium-capable 

gun facilities. 

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. 

3.8 Weapon Assembly, Storage, Testing, and Disposition 

Portfolio 

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 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. This portfolio covers all of these capabilities. 

3.8.1 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 of operations, 

equipment, facilities, and quality control, as well as special safety and security processes and protocols. 

3.8.1.1 Status of Weapon Assembly, Storage, and Disposition 

DOE/NNSA maintains extensive infrastructure to assemble, store, and dispose of weapons at a central 

site, as well as R&D capabilities throughout the enterprise. Storage and assembly of components occurs 

at some production sites, such as Pantex, SNL, and KCNSC. 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 the unavailability of parts and the emergence of 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 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 and obsolete items of equipment as well 

as the facilities in which the equipment is used. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-45 

3.8.1.2 Challenges and Strategies 

Table 3–30 provides a high-level summary of Weapon Assembly, Storage, and Disposition challenges and 

the strategies to address them. 

Table 3–30. Summary of Weapon Assembly, Storage, and Disposition challenges and strategies 

Challenges Strategies 

Sustaining aging equipment and facilities that 

support this capability due to age and condition.

Implement a strategy for major facilities, infrastructure, and 

equipment projects that includes refurbishments and replacements to 

support weapon assembly and disassembly operations. 

Mitigating the shortage of staging area for pits 

from dismantled weapons. 

Develop a strategy to address future staging capacity issues. 

3.8.2 Testing Equipment Design and Fabrication 

The Testing Equipment Design and Fabrication capability includes design, fabrication, and experimental 

deployment of special test equipment 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 levels of assembly. 

3.8.2.1 Status of Testing Equipment Design and Fabrication 

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 both production and 

surveillance. Furthermore, the quantity and complexity of data that must be collected and processed has 

challenged the sites’ ability to handle, analyze, store, and transfer data. Examples of equipment to 

address these digital data needs include digitized waveforms, high-speed video, centrifuge, higher 

frequency and shock, and simultaneous multi-environment requirements. Efforts continue to enhance 

the common tester architecture and develop the next-generation foundation bus that will improve 

connectivity, interchangeability, and multi-use compatibility with components and systems in the future. 

Many items of test equipment in this capability are one-of-a-kind, custom-designed, and custom-built 

apparatuses that test classified assemblies. While some external vendors support a few test equipment 

capabilities, currently none can handle DOE/NNSA’s unique requirements for combining test article 

classification, hazardous materials (including HE) testing, and stringent diagnostic or performance data 

collection and processing. Consequently, much of the tester design and fabrication remains in-house, 

which requires the retention of certain specialized technical expertise among staff. 

3.8.2.2 Challenges and Strategies 

Table 3–31 provides a high-level summary of Testing Equipment Design and Fabrication challenges and 

the strategies to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-46 

Table 3–31. Summary of Testing Equipment Design and Fabrication challenges and strategies 

Challenges Strategies 

Acquiring replacement parts, software upgrades, 

maintenance for test equipment, and test-specific 

hardware.

Develop a modular approach to system testers that supports 

more commonality and flexibility across systems to provide 

more cost-effective spares management, upgrade or repair 

frequencies, and operations, as well as a reduced footprint. 

Establishing the capability to test hardware performance 

under more realistic environmental conditions, such as 

combinations of stimuli. 

Obtain a design and fabricating test capability that will stress 

components and systems under multiple concurrent 

environments. 

Recapitalizing one-of-a-kind testing equipment that is 

nearing or beyond end of life and subject to single-point 

failures (e.g., system-level acceptance testers, unique 

centrifuges). 

Develop and implement a strategy to replace or modernize 

existing facilities and recapitalize programmatic equipment to 

prevent technical obsolescence.

Improving testers’ capacities and capabilities to handle, 

store, transport, retrieve, and search for relevant data 

within large data sets. 

Work with a larger consortium on developing solutions for 

handling, storage, transport, retrieval, and searching large 

amounts of data. 

Attracting and retaining staff with requisite skills. Partner with nuclear security enterprise sites to enhance 

processes for acquisition and retention of critical skills such as 

digital signal processing, field programmable gate arrays, and 

environmental testing. Partner with universities to identify and 

develop a pipeline of qualified candidates in critical fields. 

Maintaining a balance between in-house design and 

manufacturing capability with industry engagement and 

procurement. 

Continue to maintain critical capabilities in house, while using 

industry standards, hardware, and software as appropriate. 

3.8.3 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 take place 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 anomalous changes in the stockpile; potentially 

predict phenomena before the stockpile is affected; and address or mitigate issues or concerns. 

Figure 3–5. Confined Large Optical Scintillator Screen and Imaging System (CoLOSSIS) 

X-rays from a 9-megaelectronvolt linear accelerator (far right) travel through three tungsten collimators to the heavily 

shielded CoLOSSIS (far left). CoLOSSIS supports nondestructive evaluations, providing 3D images of components that 

help identify flaws or defects in materials without damaging them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-47 

3.8.3.1 Status of Weapon Component and System Surveillance and Assessment 

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. It is becoming 

increasingly difficult to maintain test equipment, gauges, and other analytical equipment and techniques 

to support surveillance needs. Efforts continue to obtain replacement parts and software upgrades to 

maintain test equipment and identify needs for gauges and other acceptance equipment to maintain 

capabilities. 

3.8.3.2 Challenges and Strategies 

Table 3–32 provides a high-level summary of Weapon Component and System Surveillance and 

Assessment challenges and the strategies to address them. 

Table 3–32. Summary of Weapon Component and System Surveillance and Assessment 

challenges and strategies 

Challenges Strategies 

Managing the additional strain on aging facilities 

and equipment due to increased workload 

throughout the enterprise. 

DOE/NNSA is deploying innovative management tools to facilitate a 

data-driven, risk-informed planning process that will guide investment 

decisions. Furthermore, multiple capabilities will come on line and be 

available for use in FY 2020 that will improve capacity for planned 

warhead modernizations and related activities. 

Performing adequate surveillance with a decrease 

in the overall size of the stockpile, which limits the 

availability of test assets to pull from inventory for 

surveillance. 

Improve and adjust surveillance, including an increased emphasis on 

nondestructive diagnostics to optimize, and potentially reduce, 

destructive testing of major components.

Performing adequate surveillance in the face of 

deterioration of supporting capabilities. 

Coordinate the programs that maintain these capabilities to develop 

risk-driven plans for recapitalization of capabilities as needed to sustain 

performance of the Surveillance program. Bring multiple capabilities on 

line for use in FY 2020 that will improve capacity and/or data quality, 

including:

• Graded collimation/computed tomography and built-in glovebox 

microscopy capabilities at Y-12 

• Pit nondestructive evaluations (increased gas sampling, assessment of 

weigh and leak capabilities; CoLOSSIS computed tomography 

maintenance and upgrades) 

CoLOSSIS = Confined Large Optical Scintillator Screen and Imaging System 

3.9 Transportation and Security Portfolio 

The Transportation and Security portfolio involves DOE/NNSA’s capabilities for protecting the people, 

places, information, and other aspects that are critical to the function of the nuclear security enterprise. 

The Secure Transportation capability provides safe, secure transport of the Nation’s nuclear weapons, 

weapon components, and SNM throughout the nuclear security enterprise to meet nuclear security 

requirements and support DOE/NNSA operations. The Physical Security capability protects all nuclear 

materials, infrastructure assets, and the workforce at DOE/NNSA sites that are 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. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-48 

3.9.1 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 related to consolidating 

storage of nuclear material and reducing the dangers 

and environmental risks posed by domestic transport 

of nuclear cargo. This capability includes design and 

fabrication or modification of vehicles, design and 

fabrication of special communication systems, and 

training of Federal agents. 

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 Government agencies. The capability also supports the 

recovery of nuclear materials from partner nations. 

The Secure Transportation Asset program (STA), 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 Government owned and operated due to the control and coordination 

required and the potential security consequences of material loss or compromise. 

3.9.1.1 Status of Secure Transportation 

DOE/NNSA 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 workforce. 

The process of identifying, designing, procuring, and manufacturing vehicles takes several years. The 

Safeguards Transporter (SGT) fleet vehicles began reaching the end of their projected design life cycle in 

2018. DOE/NNSA is sustaining this capability by implementing a risk-reduction initiative to extend the life 

of the SGT until a replacement, known as the Mobile Guardian Transporter (MGT), becomes operational. 

The MGT is critical for the safety and security of weapon related cargo, protect the public, and meet 

nuclear explosive safety standards. Without an effective MGT, future mission transportation needs will 

be at risk. 

DOE/NNSA maintains the Secure Transportation capability by sustaining its vehicle fleet with replacement 

armored tractors, escort, and support vehicles. In 2021, DOE/NNSA will design and begin production of 

the next-generation Armored Tractor (T4) and Escort Vehicle (EV4). 

A business case analysis to review options for replacing DOE/NNSA’s aging DC-9 supported the planned 

purchase of an aircraft in FY 2021. The business case also supports a long-range replacement plan for the 

two 737 aircraft. DOE/NNSA currently plans to replace the first 737 in 2025 and the second in 2029.

As with other capabilities, DOE/NNSA 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 

takes into account the many years it takes to achieve substantial growth in the Federal Agent workforce 

due to the stringent hiring process, security clearances, and attrition. 

Mobile Guardian Transporter (Test Article) 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-49 

3.9.1.2 Challenges and Strategies 

Table 3–33 provides a high-level summary of Secure Transportation challenges and the strategies to 

address them. 

Table 3–33. Summary of Secure Transportation challenges and strategies 

Challenges Strategies 

Sustaining the SGT fleet beyond the design life in the face 

of difficulties replacing obsolete parts, finding new 

manufacturers, and meeting Nuclear Explosive Safety 

Study requirements.

Develop the MGT to replace the aging SGT. Work with partners 

to identify mitigation strategies, address Nuclear Safety Study 

requirements, and sustain the SGT capability. Implement an 

SGT risk-reduction program.

Sustaining the aging Tractor Control Unit communications 

hardware/software, which provides critical communication 

functionality in vehicles. 

Redesign the Tractor Control Unit to accommodate updated 

communications and security for the SGT and MGT.

Supporting DOE/NNSA missions in the face of aircraft 

performance issues and payload restrictions. 

Support a charter aircraft contract. Procure a DC-9 

replacement aircraft. 

Maintaining and operating aging facilities and 

infrastructure safely and securely. 

Repair, upgrade, and enhance STA facilities to meet safety, 

security, and mission requirements. 

MGT = Mobile Guardian Transporter 

SGT = Safeguards Transporter 

STA = Secure Transportation Asset

3.9.2 Physical Security 

The Physical Security capability protects the Nation’s nuclear materials, infrastructure assets, and the 

workforce at DOE/NNSA sites involved in Weapons Activities from theft, diversion, sabotage, espionage, 

unauthorized access, compromise, and other hostile or noncompliant acts that may adversely affect 

national security; assures program continuity; and provides employee security. The Physical Security 

capability includes the protection, control, and accounting of materials, physical security, and information 

for all facilities within the nuclear security enterprise. These physical measures are deployed to mitigate 

a broad range of threats to DOE/NNSA at all locations. The current growth in Weapons Activities programs 

mandates increases to the physical security capabilities necessary to support ongoing modernization 

efforts, including the addition of personnel in each of the safeguards and security functional areas and 

commensurate increases in the ongoing security infrastructure modernization effort. 

Physical security technology management at the various DOE/NNSA sites includes alarm management and 

control, intrusion detection and assessment, access controls, contraband detection, barriers and locks, 

material accountability, technical surveillance countermeasures, tactical systems, remotely operated 

weapon systems, and countering unmanned aircraft systems. For specific system and site information 

refer to the SSMP classified Annex. 

3.9.2.1 Status of Physical Security 

DOE/NNSA deploys state of-the-art technologies to manage various aspects of physical security to execute 

a single, resilient, world-class security program across the nuclear security enterprise. Key aspects of 

these technologies are illustrated in Figure 3–6, and the current status is described in Table 3–34. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-50 

Figure 3–6. Physical security composition 

Table 3–34. Physical Security status 

Physical Security Component Status 

Alarm Management and Control 

Systems

Employing a proprietary physical security system to protect assets at Security 

Category I/II sites. The system is deployed at three sites; deployment of the system 

at the fourth site is scheduled to be completed in FY 2020. 

Intrusion Detection Systems/Access 

Control Systems

Collaborating with DoD to develop a reliable, rapidly deployable, portable perimeter 

security system for the temporary protection of high-value assets. 

Developing a standardized security systems training program for operators and 

system maintainers. 

DOE/NNSA’s proprietary security system is being installed at the last SNM Category I 

facility. 

Material Control and Accountability DOE/NNSA completed its modernization of the standardized accounting software 

in 2019. Currently, all but one site uses this accounting software; the remaining site 

will transition to this standardized accounting system software by 2023. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-51 

Physical Security Component Status 

Protective Force Developed Tactical Casualty Care initiative. Phase I, Train-the-Trainer, was 

completed in 2019. Phase II, Procurement of Equipment, is ongoing and is scheduled 

to be completed in FY 2020. 

Used an existing DoD contract to acquire standardized, enterprise-wide primary 

individual weapons: 

x Reduces need for multiple weapon parts stockpiles 

x Supports bulk supply orders to reduce overall cost and provide seamless mutual 

support initiatives among the DOE/NNSA sites 

x Initial delivery of new individual weapons is expected in the fourth quarter of 

FY 2020 

Through the Enterprise Mission Essential Task List, DOE/NNSA has restructured 

training with a primary focus on critical tasks that directly contribute to mission 

success. 

Enterprise Safeguards and Security 

Planning and Analysis Program

Continuing to conduct standardized vulnerability assessments of DOE/NNSA 

facilities, providing risk acceptance authorities’ critical program information to help 

guide/manage the safeguards and security program. 

Security Management Improvement 

Program (SMIP) 

The SMIP Pilot was conducted and completed at the Nevada National Security Site in 

November 2019. 

SNM = special nuclear material 

Note: A complete breakdown of physical security technology management at each NNSA site is available in the SSMP classified 

Annex. 

3.9.2.2 Physical Security Challenges 

Aging security infrastructure, with some physical security systems older than 30 years, drove DOE/NNSA 

to develop a standardized approach for prioritizing critical physical security system upgrades and life-cycle 

management at each DOE/NNSA site, plant, and laboratory. The 10-Year Security Infrastructure 

Revitalization Program Plan provides a prioritized, cost-effective schedule of recommended physical 

security system investments, assuming appropriate funding is provided. Failure to maintain the schedule 

will increase the risk to security and could affect critical weapons program production activities. 

Table 3–35 provides a high-level summary of Physical Security challenges and the strategies to address 

them. 

Table 3–35. Summary of Physical Security challenges and strategies 

Challenges Strategies 

Identifying emerging threats and ensuring capabilities are 

developed and implemented to counter threats. 

Collaborate with numerous internal and external entities. 

Assessing and addressing the full range of threats, from 

protestor incursions to active, violent insiders or 

intruders.

Participate in executing the DOE Insider Threat Program through 

local Insider Threat Working Groups at each DOE/NNSA site. 

Operate a Security Analysis Cell to analyze and disseminate 

external threat information and interface with the intelligence 

community and law enforcement agencies. 

Ensuring security requirements are factored into NNSA 

mission planning efforts (i.e., production capabilities, 

infrastructure modernization, etc.) and appropriate 

resources are provided to support those requirements. 

Coordinate with NNSA stakeholders to integrate security 

requirements into NNSA mission planning efforts. 

Ensuring all security-related projects (i.e., line items, 

General Plant Projects, and other minor construction 

projects) are executed on time, within budget, and to 

specification. 

Track project implementation through recurring Annual 

Operating Plan updates, field-based Program Execution Reviews, 

and supplementary, monthly project reports as necessary.
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-52 

3.9.3 Information Technology and Cybersecurity 

The IT and Cybersecurity capability provides infrastructure and protection for both classified and 

unclassified computing networks, secure communications, applications, systems, and logical 

environments. Efficient and effective operations and protection of unauthorized access and malicious 

acts that would adversely affect national and economic security of electronic information and information 

assets is vital for the DOE/NNSA. DOE/NNSA directs the design, development, and maintenance of all 

aspects of DOE/NNSA computing and provides DOE/NNSA staff with the IT resources necessary to achieve 

mission goals and objectives. Core components and functions of the IT and Cybersecurity capability are 

influenced and supported by Policy and Governance, as illustrated in Figure 3–7. 

Figure 3–7. Information Technology and Cybersecurity Capability core functions 

Efficient and effective management of IT and Cybersecurity is one of the most crucial factors in supporting 

the DOE/NNSA enterprise; every capability in the nuclear security enterprise depends on IT and 

Cybersecurity to keep information and related assets securely protected and well managed. The highly 

complex nature of the DOE/NNSA enterprise, coupled with resource priorities, requires information and 

information assets to be secured, managed, and protected using a risk-management approach. 

DOE/NNSA makes well-informed management decisions based on a systematic understanding of the risks 

inherent in the use of information systems to properly protect assets and information. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-53 

3.9.3.1 Status of the Information Technology and Cybersecurity 

DOE/NNSA’s IT and Cybersecurity capability supports and underpins the DOE/NNSA mission and provides 

secure, reliable, well-managed, and accessible IT solutions critical to executing DOE/NNSA’s missions. 

Table 3–36 describes key aspects of the IT and Cybersecurity capability and the current status. 

Table 3–36. Information Technology and Cybersecurity status 

IT/Cyber Component Status 

Information Technology 

Modernization

Implemented Phase 1 of the IT Modernization effort. 

Continuing to work with DOE to complete modernization of the current IT 

infrastructure provided to Departmental elements and the move to a managed service 

model. 

Enterprise Secure Computing Continuing to pursue a strategic initiative as part of the larger Enterprise Secure 

Computing program, which will directly increase the capability, capacity, and 

responsiveness of the DOE classified infrastructure. This will directly support the 

DOE/NNSA mission and statutory requirements governing classified data protections 

and information assurance. 

Restricted Data Continuing to work with external partners (including other Government agencies and 

the intelligence community) to identify interagency needs and opportunities for 

accessing, sharing, leveraging, and protecting Restricted Data (RD) by:

x Providing a list of current cyber protection requirements and methodologies for RD

x Explaining the current congressional statutes that control dissemination of RD 

outside the DOE/DoD environment 

x Assessing the current state of the Federal Bureau of Investigation cybersecurity 

controls in correlation with RD protection requirements and assisting in the 

formulation of an official memorandum from the Associate Director of the Render 

Safe Program to the NNSA Office of the Chief Information Officer, requesting access 

to host RD 

x Developing and integrating an RD overlay for external partners to enforce protection 

across environments that are outside of DOE/NNSA’s direct control and oversight 

Technologies Deployed to Address 

Cybersecurity Threats

Maintaining management, operations, and technical security safeguards throughout 

the nuclear security enterprise for adequate protection of information assets.

Developed, deployed, and used security tools to provide the first lines of defense 

against known adversaries and emerging threats. 

3.9.3.2 Challenges and Strategies 

The cyber threat landscape constantly evolves, with the most sophisticated threats adapting rapidly to 

deterrents. DOE/NNSA is committed to providing an IT infrastructure to protect the stockpile stewardship 

and management missions using a collaborative, intelligence-informed approach to cyber operations and 

a response that employs the full capabilities of the nuclear security enterprise, DOE, and the Federal 

Government. Table 3–37 provides a high-level summary of the IT and Cybersecurity challenges and the 

strategies developed to address them. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 3-54 

Table 3–37. Summary of Information Technology and Cybersecurity challenges and strategies 

Challenges Strategies 

Addressing current supply chain and software 

assurance issues. 

Move toward centralized purchasing and equipment review before 

issuing equipment to the field. 

Developing a more robust Insider Threat program 

for emerging threats. 

Work with counterintelligence on implementation of an insider threat 

program. 

Managing aging computing infrastructure. 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. Implement faster development and application of 

these capabilities to counter such threats. 

Addressing limitations of current network 

monitoring services. 

Upgrade sites across the enterprise through deployment of new 

cybersecurity solutions. 

Supporting scientific computing and increased 

reliance on computers across the DOE/NNSA 

complex.

Work with the Office of Infrastructure, Operations, and Modernization 

to optimize infrastructure and the Office of Advanced Simulation and 

Computing and Institutional R&D to perform capacity planning for 

DOE/NNSA. 

Addressing new requirements from the 2018

Nuclear Posture Review. 

Assess methods for IT and Cybersecurity programs are poised to support 

new and emerging mission requirements. 

Filling critical cybersecurity and IT vacancies across 

the enterprise.

Hire a workforce that has the required skills per DOE/NNSA strategic 

plans. Invest in employee development to cultivate a high-performing 

workforce that will support DOE/NNSA's mission today and into the 

future. Incorporate student participation in the DOE/NNSA Cyber 

Summit. 

Fulfilling Office of Management and Budget 

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.

Managing operational technology cybersecurity. Establish an effective methodology to accurately baseline present and 

future operational technology (OT) devices in use across both the NNSA 

Production Office and the nuclear security enterprise. Work with 

external partners on a path forward and partner with the Office of 

Defense Programs to determine toolsets that are necessary to develop 

and support a strategic approach. Implement recommendations 

identified in the OT/IT study performed by the JASON independent 

advisory group. 

Managing software assurance. Work with strategic DoD partner to increase awareness, capabilities and 

tools, and consistent approaches to effectively detect evidence of 

malicious features. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-1 

Infrastructure and Workforce 

The National Nuclear Security Administration Strategic Vision

recognizes infrastructure and workforce as two of the seven 

strategic management challenges that requires immediate 

attention. DOE/NNSA is committed to making concerted 

investments in infrastructure and workforce initiatives to 

support increasing scope and address the state of decline 

across the nuclear security enterprise. As detailed in the 

beginning of Chapter 3, infrastructure and workforce represent 

two of the four elements that comprise every Weapons 

Activities capability. The status of these elements, as well as 

challenges associated with them, are described in detail 

throughout Chapter 3. Many of the individual capability descriptions identified challenges specific to 

aging infrastructure and the need to recruit and retain a highly-skilled workforce, as well as strategies to 

mitigate those challenges. This chapter describes DOE/NNSA’s overall strategy to strengthen these 

elements from an enterprise-wide perspective. 

4.1 Infrastructure 

Infrastructure modernization efforts across the nuclear 

security enterprise are necessary to mitigate risks and 

implement the 25-year program of record described in the 

Nuclear Weapons Council Strategic Plan for Fiscal Years 

2019–2044 and in this SSMP. Efforts include investments in 

major programmatic and mission-enabling construction 

projects, as well as risk-informed, time-sensitive 

recapitalization efforts across every DOE/NNSA site. These 

complementary investments support DOE/NNSA in meeting 

the most pressing mission needs while also addressing the 

issues of an aging infrastructure across the nuclear security 

enterprise. 

Major infrastructure investments require additional scrutiny 

and follow defined acquisition methodology. DOE/NNSA 

manages line-item capital acquisition projects through DOE’s 

acquisition process with five critical decision (CD) points 

(detailed in Figure 4–1) that serve as major milestones approved by a Project Management Executive. 

Each CD marks further certainty in project scope and requires successful completion of the preceding 

phase. DOE/NNSA will sometimes combine CD-2 (Approve Performance Baseline) and CD-3 (Approve 

Start of Construction) to reduce acquisition time while maintaining program management requirements. 

Key Changes Affecting Nuclear Security 

Enterprise Infrastructure 

x Increases in near-term investments in 

specialized facilities for weapon material 

production and processing 

- A two-site solution for Pit Modernization

- High Explosives Synthesis, Formulation 

and Production Facility 

- Lithium Processing Facility 

- Tritium Finishing Facility 

- Physical security and IT enterprise 

investments 

x Increased planning resources for major 

programmatic construction investment

“Previous de-emphasis on our nuclear 

deterrent and the infrastructure that 

supports it...coupled with adversaries that 

are modernizing and creating increasingly 

capable forces, has led us to the point 

where we must modernize now to continue 

to maintain a viable deterrent in the future.” 

Charles A. Richard, Commander, United States 

Strategic Command, 2020 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-2 

Figure 4–1. Critical Decision overview 

4.1.1 Overall State of DOE/NNSA Physical Assets 

DOE/NNSA’s infrastructure is a $121 billion enterprise composed of programmatic research and 

production facilities, support facilities, and service facilities that are of critical importance for mission 

work. More than half of all DOE/NNSA facilities are more than 40 years old. Excess facilities (i.e., facilities 

that are no longer usable for mission needs) account for 10 percent of enterprise infrastructure, and 

hundreds of additional assets are expected to become excess in the next decade. These excess facilities 

must be maintained in a safe standby condition as they await decommissioning and disposition. 

Simultaneously, DOE/NNSA is addressing the declining state of infrastructure by optimizing the 

application of resources across its portfolio. DOE/NNSA has undertaken a comprehensive strategic capital 

acquisition planning effort to identify, scope, and prioritize capital investment needs across all capabilities, 

including office and laboratory space, utilities, equipment, and other supporting infrastructure. 

DOE/NNSA has established priorities based on mission needs and optimization of costs and risk reduction. 

DOE/NNSA has also deployed innovative management tools to facilitate data-driven, risk-informed 

planning that will guide integrated short- and long-term investment decisions. In addition, streamlined 

acquisition and execution techniques will standardize and deliver assets more efficiently by applying more 

commercial standards. 

4.1.2 Major Investments in Programmatic Infrastructure 

DOE/NNSA’s programmatic facilities are facing increased user demand due to multiple concurrent 

warhead modernization activities that have dramatically increased production workload as well as critical 

science, technology, and engineering activities related to stockpile stewardship. Production facilities in 

particular are facing safety, capacity, and reliability challenges. Revitalization of the pit production 

capability and continuing missions in uranium, tritium, high explosives, lithium, and non-nuclear 

component production will require significant investments in modernization of aging infrastructure and 

systems, as well as some improvements or expansions to meet increased capacity requirements. Special 

initiatives such as Exascale Computing Initiative and Enhanced Capabilities for Subcritical Experiments also 

require dedicated equipment and facilities investments. Existing facilities require additional funding for 

maintenance costs and extended bridging strategies until major programmatic construction projects are 

completed. 

DOE/NNSA developed the Capital Acquisition Planning (CAP) process to prioritize programmatic 

infrastructure investments as part of overall planning, programming, budgeting, and evaluation activities.1

 

 

1 CAP replaces the Capital Acquisition Process (CapAx) described in the FY 2020 SSMP. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-3 

This effort, consistent with the planning for DOE/NNSA’s Stockpile Major Modernization programs, is 

conducted in collaboration with the laboratories, plants, and sites to identify and prioritize major 

programmatic construction projects for Weapons Activities within the FYNSP and projected out for a 

25-year period. The CAP process uses site expertise, programmatic requirements reviews, and Federal 

cost and schedule planning estimates to develop long-term plans for major projects. The final 25-year 

schedule of major projects is determined by DOE/NNSA leadership. Integrated planning for infrastructure 

across the enterprise is detailed in the annually updated DOE/NNSA Master Asset Plan. Current planning 

estimates and schedule dates for major programmatic construction projects that are included in the 

FY 2021 President’s Budget Request are listed in Figure 4–2.

2

 Proposed major programmatic construction 

projects that are planned for after FY 2025 are listed in Figure 4–3. 

Figure 4–2. DOE/NNSA 25-year programmatic line-item schedule for projects included in the 

FY 2021 President’s Budget Request (FY 2021–FY 2025)3

 

2 Figure 4–2 includes construction projects that DOE/NNSA has requested planning funding (pre-CD-1) for within the FY 2021 

President’s Budget Request. 

3 DOE/NNSA obtained CD-0, Achieve Mission Need, approval for the Power Sources Capability facility in FY 2019 and for the 

Energetic Materials Characterization facility in FY 2020. DOE/NNSA is working toward CD-4 (Approve Start of Operations or 

Project Completion) approval for both projects in FY 2026 based on the clearly defined capability gap and mission need. The 

analysis of alternatives process for the Energetic Materials Characterization, Conceptual Design for the Power Sources Capability, 

and subsequent cost estimates for both will inform future budget planning profiles. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-4 

Figure 4–3. DOE/NNSA 25-year programmatic line-item schedule for proposed projects 

(FY 2026–FY 2045) 

The projects presented in Figures 4–2 and 4–3 are intended to reduce risk to mission by consolidating and 

replacing unreliable facilities and infrastructure that have exceeded life-cycle expectations and pose 

safety and program risks to people, the environment, and the mission. Near-term projects have higherfidelity cost and schedule data associated with them. As a result, the planned start and end dates for the 

“ongoing projects” are more certain than those in the “under review” and “new proposals” categories. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-5 

DOE/NNSA will continue to update this schedule annually based on revised and new mission needs 

assessments, cost estimates, programmatic prioritization, and the availability of funding. There will be a 

number of planned acquisitions that may convert to alternate strategies upon conduct and completion of 

an analysis of alternatives. 

4.1.3 Major Investments in Mission-Enabling Infrastructure 

In addition to a suite of programmatic facilities, DOE/NNSA is dependent on hundreds of office and 

laboratory buildings, power systems, water systems, emergency response, and other supporting assets 

for programs to function. Similar to the situation with direct mission assets, increases in workload and 

associated staffing are creating a shortage of mission-enabling facilities such as office and laboratory 

space. These aging facilities and systems require maintenance, updating, refurbishment, or replacement. 

Regular investments in power transmission and distribution systems are necessary to avoid safety, 

security, and productivity issues that stem from age and obsolescence. Growth in high performance 

computing requires increased electrical capacity at some sites, while more efficient manufacturing 

technologies and processes at other sites have reduced power requirements. Efforts are underway to 

improve the reliability, capacity, sustainability, and coverage of electrical infrastructure across the 

enterprise. 

Regular investments are also needed to maintain a viable water supply and distribution system, sewers, 

tanks, and other water infrastructure. Activities are underway to mitigate the risk of single point failures 

for the water supply throughout the enterprise. Strategic investments in mission-enabling infrastructure 

are prioritized to address increased program requirements and reduce infrastructure risks to capabilities. 

DOE/NNSA is using the major capital acquisition construction process to address capacity issues and safety 

concerns in utilities, office and laboratory space, and emergency response, as illustrated in the 25-year 

mission-enabling infrastructure line-item schedule in Figure 4–4. 

Figure 4–4. DOE/NNSA 25-year mission-enabling infrastructure line-item schedule 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-6 

4.2 Workforce

DOE/NNSA’s greatest asset is the highly qualified and skilled world-class scientific and engineering 

workforce, without which DOE/NNSA could not meet its vital national security missions. One of 

DOE/NNSA’s top mission enabling priorities is to strengthen key science, technology, and engineering 

capabilities, including recruiting, training, and retaining the next generation of DOE/NNSA’s scientists, 

engineers, project and program managers and technicians. This section emphasizes the overall 

importance of staffing to maintaining capability qualifications, expertise, and competencies, and the 

approach DOE/NNSA is using to address these issues at a strategic, enterprise level. 

Over one-third of the workforce is now retirement-eligible, posing a challenge to DOE/NNSA in bringing 

new hires up to speed while the expertise and experience is still available. Maintaining a DOE “Q”-cleared, 

qualified, and technically-trained workforce requires transferring knowledge, skills, and direct experience 

with respect to all stockpile technologies and processes. Because the expertise required to fulfill 

DOE/NNSA’s mission is often learned on-the-job over a significant period of time, retention of the 

workforce is critical to the development, growth, and maintenance of the workforce’s scientific, 

engineering, technical, and project/program management competencies. 

DOE/NNSA‘s approach to addressing its workforce challenges recognizes five keys characteristics 

necessary to attract and retain a high-quality workforce: 

 Owning a place in the mission 

 Working with state-of-the-art experimental, computational, and manufacturing capabilities 

 Employing modern business and operating systems 

 Working in modern workspaces 

 Providing ample career development opportunities 

On an enterprise level, DOE/NNSA is focused on retaining and preparing the workforce for the future 

through succession planning, knowledge preservation, training, retention, and workforce development. 

Each management and operating (M&O) partner site has a variety of established programs to improve 

retention: 

 Critical skill retention programs that provide pay incentives for hard-to-fill critical positions 

 Employee leadership development programs 

 Increased employee engagement through career conversations, career development tools, 

workshops, and mentoring 

 Educational opportunities and assistance to encourage career growth 

 Flexible work schedules and other family-friendly workplace options 

 Rotational assignments to diversify experience 

The M&O partner sites have placed increased emphasis on career development opportunities and strong 

employee engagement and are committed to attracting and retaining top talent. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-7 

For FY 2019, the M&O partner sites collectively reported a headcount of 44,444 employees.4 This is an 

increase of 3,926 employees from the reported 40,518 in the FY 2020 SSMP. This increase is reflected 

across all job categories as depicted in Figure 4–5. Despite attrition, the nuclear security enterprise 

experienced a positive net gain. 

The M&O partners reported 2,192 separations during FY 2019, as depicted in Figure 4–6. Broken down 

by reason for separation, the data in Figures 4–7 and 4–8 identify two very noticeable issues. One is that 

most voluntary separations occur within 0-5 years of service, and the second is that the voluntary 

separations are concentrated in age groups that would ideally learn from and replace retirees. These 

voluntary separations amount to six percent of the workforce. Overall, site attrition rates have compared 

favorably to the estimated industry average. 

Figure 4–5. Total M&O workforce by Common Occupational Classification System 

 

4 This total is not all-inclusive for the entire nuclear security enterprise workforce of over 50,000 personnel. For reporting 

purposes, the SSMP collects data in headcount form for M&O permanent career employees based on categories from the 

Common Occupational Classification System. This data does not include Naval Reactors or Federal workforces, and exclude parttime or other personnel that fall outside one of these categories. Comprehensive Federal data is presented to Congress outside

of the SSMP. At the time of data collection (9/30/19), DOE/NNSA had around 1,700 Federal FTEs (not counting Office of Secure 

Transportation couriers); DOE/NNSA, to fulfill its growing workload, was authorized to increase its desired end-strength FTE cap 

to 1,890, as opposed to the 1,690 stated in previous SSMPs. DOE/NNSA also has several support-service contractors in Federal 

program offices providing crucial advisory and programmatic services. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-8 

Figure 4–6. M&O separations in FY 2018 and FY 2019 

Figure 4–7. M&O separations by years of service 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 4-9 

Figure 4–8. M&O separations by age 

Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-1 

Chapter 5 

Budget and Fiscal Estimates 

The FY 2021 President’s Budget Request for Weapons Activities seeks appropriations from Congress 

needed to support the Administration’s nuclear deterrent modernization program as described in the 

2018 Nuclear Posture Review. The FY 2021 President’s Budget Request provides an increase of 19 percent 

for DOE/NNSA, and 25 percent for Weapons Activities above the FY 2020 enacted appropriation. These 

robust increases are needed to support the warhead modernization programs and the infrastructure 

modernization projects required to deliver these warheads on schedule. 

DOE/NNSA developed the FY 2021 Future Years Nuclear Security Program (FYNSP) budget request for 

Weapons Activities using a detailed, bottom-up assessment of DOE/NNSA’s capabilities and a thorough 

alignment of warhead programs to DOE/NNSA requirements. The assumptions encompassed by this 

request meet the timeline for DOE/NNSA’s warhead deliveries to be fully synchronized with the 

modernization of DoD delivery platforms. 

The first half of this chapter displays budgetary information based on the FYNSP request, which includes 

programming for FY 2021 through FY 2025. The FY 2021 budget request makes use of a new budget 

structure for Weapons Activities that better accounts for the full scope of activities undertaken in this 

area. Each programmatic section in this chapter compares the FY 2021 budget request to the FY 2020 

enacted budget (comparable) and presents key milestones representing progress toward program goals. 

The second half of the chapter describes cost projections for selected programs beyond the FYNSP, and 

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 this 25-year program 

and an analysis of the affordability of the Weapons Activities program. 

5.1 Future Years Nuclear Security Program Budget 

FY 2021 Budget Structure Change 

The FY 2021 FYNSP budget request for Weapons Activities reflects an updated structure that better aligns 

with current and future Weapons Activities programming; production modernization programming; and 

research, technology, and engineering efforts. It also improves alignment with the current and future 

scope, consolidates similar activities, and facilitates improved program execution by grouping activities 

by how they are managed. A high-level overview of these changes is presented in Figure 5–1. Additional 

details about the budget request are provided in the ensuing sections and can be found in the Department 

of Energy FY 2021 Congressional Budget Request. As a result of the budget structure change, all 

references to the FY 2020 enacted budget in this chapter are provided as comparable numbers to the new 

budget structure for FY 2021.1

 

 

1 The complete budget crosswalk from the FY 2020 enacted budget structure to the FY 2021 requested budget structure can be 

found in the Department of Energy FY 2021 Congressional Budget Request.
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-2 

Figure 5–1. FY 2020 – FY 2021 Weapons Activities Budget Structure Comparison 

FY 2021 Future Years Nuclear Security Program Request 

Weapons Activities provides for maintenance and refurbishment of nuclear weapons to sustain 

confidence in their safety, reliability, and military effectiveness; investment in scientific and engineering 

capabilities for certification of the nuclear weapons stockpile; and increased manufacturing capabilities 

to produce nuclear weapon components. Weapons Activities also provides for maintenance and 

investment in DOE/NNSA’s infrastructure. 

The FY 2021 FYNSP budget request supports the current stockpile, warhead modernization activities, 

recapitalization and modernization programs for infrastructure, and filling gaps in DOE/NNSA’s 

reestablishment of necessary production capabilities. It also supports R&D efforts and personnel growth 

in operations, physical security, and information technology (IT) and cyber security to support expanding 

program needs. 

DOE/NNSA must continue to meet DoD requirements to accomplish warhead modernization programs, 

as well as meet the highest standards of safety, security, and effectiveness while remaining aligned and 

integrated with DoD’s delivery platform modernization. DOE/NNSA will continue to work with DoD 

through the Nuclear Weapons Council to evaluate, maintain, and assure the safety, security, and control 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-3 

of the nuclear weapons stockpile, as well as develop nuclear weapons stockpile and integrated platform 

delivery system options. 

Table 5–1 displays the FY 2020 enacted budget and program budget requests for Weapons Activities for 

FY 2021–FY 2025. The figures and narrative that follow describe the FY 2021 budget request in more 

detail. 

Table 5–1. Overview of Future Years Nuclear Security Program budget request for 

Weapons Activities in FY 2020 – FY 2025a

Activity 

Fiscal Year (dollars in millions) 

2020 

Enacted 

(Comp) 

2021

Request 

2022

Request 

2023

Request 

2024

Request 

2025

Request 

Stockpile Management 3,680.1 4,284.2 4,562.5 4,612.6 4,723.3 5,182.2 

Production Modernization 1,565.5 2,457.9 2,999.5 3,504.0 3,393.3 3,172.8 

Stockpile Research, Technology, and Engineering 2,553.1 2,782.1 2,746.3 2,778.7 2,940.2 2,961.7 

Infrastructure and Operations 3,199.5 4,383.6 3,944.8 3,674.6 3,784.8 3,839.8 

Secure Transportation Asset 292.7 390.1 336.8 345.3 354.7 381.0 

Defense Nuclear Security 775.0 826.9 916.5 880.1 939.9 932.8 

Information Technology and Cybersecurity 300.0 375.5 387.3 394.0 403.4 415.2 

Legacy Contractor Pensions 91.2 101.7 43.4 81.6 73.5 77.6 

Adjustments 0.0 0.0 0.0 0.0 0.0 0.0 

Weapons Activities Total 12,457.1 15,602.0 15,937.0 16,271.0 16,613.0 16,963.0 

a Totals may not add because of rounding. 

5.2 Stockpile Management 

Stockpile Management encompasses four major subprograms that directly support the Nation’s nuclear 

weapons stockpile: (1) Stockpile Major Modernization; (2) Stockpile Sustainment; (3) Weapons 

Dismantlement and Disposition (WDD); and (4) Production Operations. Stockpile Major Modernization 

extends the lifetime of the Nation’s nuclear stockpile while addressing required updates, replacing aging 

or obsolete components for continued service life, and enhancing security and safety features. Stockpile 

Sustainment performs direct tail-specific and multi-system sustainment activities for all current weapons 

systems in the stockpile, including maintenance, surveillance assessment, development studies/capability 

improvements, and weapon program planning/support for each weapon system. WDD dismantles retired 

weapons and properly disposes of retired components from the stockpile. Production Operations 

provides common manufacturing processing services; maintenance and replacement of equipment; and 

calibration services common to the weapon programs for manufacturing operations to meet DoD War 

Reserve requirements. 

Budget 

The budget request for Stockpile Management increased 16 percent from the FY 2020 enacted budget 

(comparable) and is illustrated in Figure 5–2. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-4 

Figure 5–2. Funding schedule for Stockpile Management, FY 2020 – FY 2025 

FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

5.2.2.1 Stockpile Major Modernization (previously Life Extension Programs and Major 

Alterations) 

Stockpile Major Modernization was renamed from the Life Extension Programs (LEPs) and Major 

Alterations (Alts) Program in the Directed Stockpile Work Program budget restructure and contains the 

subprograms of: (1) B61 LEP; (2) W88 Alteration Program; (3) W80-4 LEP; (4) W87-1 Modification 

Program; and (5) W93. Stockpile Major Modernization encompasses the programs necessary to meet 

DoD warhead modernization requirements and for the projected 20- to 30-year in-service life. 

The increased budget request for Stockpile Major Modernization principally represents the planned rampup of the W80-4 LEP to accomplish Phase 6.3 (Development Engineering) activities, Conceptual Design 

Reviews, production of warhead simulators/test units, and hydrodynamic physics tests to support nuclear 

certification; the planned ramp-up of the W87-1 Modification Program across all areas to complete 

Phase 6.2 (Feasibility Study and Design Options) deliverables before entry into Phase 6.2A (Design 

Definition and Cost Study); and the W93 planned Phase 1 (Concept Assessment) and refinement activities. 

5.2.2.2 Stockpile Sustainment (previously Stockpile Systems) 

Stockpile Sustainment is responsible for accomplishing sustainment activities for the total (active and 

inactive) stockpile for the B61, W76, W78, W80, B83, W87, and W88 weapons. The eighth subprogram, 

Multi-Weapon Systems, provides multi-weapon products across the nuclear security enterprise for 

maintenance (e.g., military spares, transportation equipment, and handling gear), surveillance 

(e.g., weapon system testing, component testing, and analysis), assessments (e.g., use control and 

weapon operations analysis), and management (e.g., integrated digital engineering databases and tools, 

weapons training, and military liaison). 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-5 

The budget request for Stockpile Sustainment also supports: 

 Development of new joint test assembly designs for the W76 and W78 

 W87 Ground-Based Strategic Deterrent qualification and integration activities with DoD 

 Development of improved shipping configurations (Integrated Surety Architecture activities) for 

weapons in transportation mode 

 Preparation activities to sustain the B61-12 in the stockpile 

5.2.2.3 Weapons Dismantlement and Disposition 

WDD contains weapon dismantlements, safety studies on retired systems, material characterization, and 

the disposal of weapon parts. 

The budget request for WDD, combined with the FY 2020 carryover, represents level work activities for 

weapon and canned subassembly dismantlements, recycle requirements, and reduction of legacy 

component inventories. 

5.2.2.4 Production Operations (previously Production Support) 

Production Operations was renamed from Stockpile Services, Production Support, in the budget 

restructure. It provides a manufacturing-based program that provides individual site production base 

capabilities for weapon modernization; maintenance, surveillance, assembly and disassembly; and safety 

and reliability testing. 

The increased budget request for Production Operations represents continued growth to underpin the 

warhead modernization workload, assuring procedures and prerequisite process equipment are in place 

to meet warhead modernization first production unit requirements. The program will expand production 

line responsiveness to better sustain workload capacity for warhead modernization activities. The funding 

will also provide the processes needed to certify weapons and components, and the production schedule 

through product qualification. 

Key Milestones 

In order to sustain and modernize the stockpile, DOE/NNSA must meet the key Stockpile Management 

milestones illustrated in Figure 5–3.

2

 Significant changes from last year’s plan are:3

 The FY 2020 milestone, Deliver first production unit of the W88 Alt 370, was changed to FY 2021 

by the Nuclear Weapons Council 

 The FY 2022 milestone, Complete Phase 6.2 activities for the W87-1 Mod Program, was 

accelerated to FY 2021 by the FY 2018 Nuclear Posture Review and subsequent Nuclear Weapons 

Council implementation to meet program requirements 

 The FY 2020 milestone, Deliver first production unit of the B61-12 LEP, was changed to FY 2022 by 

the Nuclear Weapons Council 

 

2 These key milestones do not include key annual deliverables, such as completing the Annual Assessment Process culminating in 

the national security laboratory (LANL, LLNL, and 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. 

3 As a result of the FY 2021 budget structure change, some milestones previously captured under Directed the Stockpile Work are 

now under the Stockpile Research, Technology, and Engineering. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-6 

One milestone from last year’s SSMP was completed in FY 2020:

 Complete project closeout activities for the W76-1 LEP and W76-2 Modification Program. The 

W76-1 LEP completed warhead production in December 2018 and deliveries to the Navy in 

April 2019, ahead of schedule and within planned budgets

There were no substantive changes to the remainder of the Stockpile Management milestones included 

in Figure 5–3. 

Figure 5–3. Key milestones for Stockpile Management 

5.3 Production Modernization 

Production Modernization is focused on production capabilities for nuclear weapons and consists of four 

major subprograms that sustain the Nation’s principal nuclear weapons production capabilities: 

(1) Primary Capability Modernization; (2) Secondary Capability Modernization; (3) Tritium and Domestic 

Uranium Enrichment; and (4) Non-Nuclear Capability Modernization. Modernization efforts within this 

program focus on the capability to manufacture nuclear weapons components that are critical to weapon 

performance. The program’s scope includes restoring and increasing strategic component manufacturing 

and processing capabilities across the national security enterprise to meet mission requirements. 

Budget 

The budget request for Production Modernization increased 57 percent from the FY 2020 enacted budget 

(comparable) and is illustrated in Figure 5–4. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-7 

Figure 5–4. Funding schedule for Production Modernization, FY 2020 – FY 2025 

FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

5.3.2.1 Primary Capability Modernization 

Primary Capability Modernization consolidates management of nuclear material processing capabilities. 

The program includes (1) Plutonium Modernization (previously Plutonium Sustainment) and (2) High 

Explosives and Energetics. The Plutonium Modernization Program includes three subprograms: 

Los Alamos Plutonium Modernization, Savannah River Plutonium Modernization, and Enterprise 

Plutonium Support. The major construction projects for pit production at LANL (Plutonium Pit Production 

Project) and SRS (Savannah River Plutonium Processing Facility) are currently included under Primary 

Capability Modernization to encompass the full scope of the Plutonium modernization effort. These 

construction projects will eventually move to Infrastructure and Operations. 

The budget request for this program increased to cover programmatic equipment investments and critical 

skills necessary to meet pit production process development and qualification activities. This increase will 

also provide for equipment installation at LANL to increase the pit production capability and invest in the 

infrastructure necessary to increase production capability to 30 pits per year during 2026. Funding for 

High Explosives and Energetics will support infrastructure modernization and establish a modern and 

robust production and manufacturing capability. 

5.3.2.2 Secondary Capability Modernization 

Secondary Capability Modernization is responsible for restoring and improving manufacturing capabilities 

for the secondary stage of nuclear weapons. The program includes three subprograms: (1) Uranium 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-8 

Modernization4 (previously Uranium Sustainment); (2) Depleted Uranium Modernization; and (3) Lithium 

Modernization (previously Lithium Sustainment). 

The budget request for Secondary Capability Modernization increased to support new depleted uranium 

scope to meet near-term mission requirements and future weapon systems. This increase will also cover 

additional scope to supply the current stockpile with purified enriched uranium metal, and support the 

transition of new capabilities into modern and enduring uranium facilities. Funding for Lithium 

Modernization increased to process material for the B61-12 LEP and sustaining the current processing 

capability until the Lithium Processing Facility is operational. 

5.3.2.3 Tritium and Domestic Uranium Enrichment 

Tritium and Domestic Uranium Enrichment is responsible for producing tritium and supplying unobligated 

low enriched uranium to support DoD requirements. The program includes two subprograms: (1) Tritium 

Modernization (previously Tritium Sustainment) and (2) Domestic Uranium Enrichment. 

The budget requests for Tritium Modernization and Domestic Uranium Enrichment increased to support 

ongoing activities including, but not limited to, continuing the down-blending campaign and continuing to 

preserve and advance uranium enrichment expertise and technology to meet current and future 

U.S. Government needs. Increases in Tritium Modernization will support increased tritium-producing 

burnable absorber rod irradiation and the ramp-up to full operations at the Tritium Extraction Facility, as 

well as tritium process R&D. 

5.3.2.4 Non-Nuclear Capability Modernization 

Non-Nuclear Capability Modernization provides funding to modernize production of non-nuclear 

components for use in multiple weapon systems. This program consolidates management and oversight 

of strategic investments in technology, equipment, infrastructure, tools, and materials. Specifically, the 

program focuses on improving and/or increasing the capability and capacity of the DOE/NNSA nuclear 

security enterprise to manufacture stockpile components in categories that include (but are not limited 

to) cable assembles, neutron generators, power sources, and gas transfer systems. 

Key Milestones 

To properly support the current and future nuclear deterrent mission, DOE/NNSA must invest in reestablishing production capabilities and modernizing programmatic infrastructure.5

 Key milestones for 

Production Modernization are in Figure 5–5.

6

 Changes from last year’s plan are: 

 

4 Uranium Modernization also includes the scope and funding for Process Technology Development, which was previously under 

Research Development, Test, and Evaluation’s Advanced Manufacturing Development program. 5 Although programmatic construction projects are funded through Infrastructure and Operations, milestones for relevant 

projects are included in this section for transparency. Many of the capabilities depend on the completion of programmatic 

construction projects to execute the mission. 6 Key milestones beyond the FNYSP represent planned activities to meet DoD requirements and are contingent on future resource 

decisions. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-9 

Key milestone changes related to Production Modernization capabilities: 

 The FY 2021 milestone, Install development direct cast furnace, was added

 The FY 2021 milestone, Complete specification for insensitive high explosive (TATB/PBX-9502), 

was added 

 The FY 2023 milestone Obtain Critical Decision 4 (CD-4) (Approve Start of Operations or Project 

Completion) for the Y-12 plant electrorefiner, was added 

 The FY 2024 milestone, Produce first War Reserve production lot of insensitive high explosive 

(PBX-9502), was added 

 The FY 2024 milestone, Produce a qualified binary ingot by restarting lapsed manufacturing 

processes, was added 

Key milestones changes related to production infrastructure: 

 The FY 2021 milestone, Obtain Critical Decision 3A (CD-3A; Approve Long Lead Item Procurements) 

for the Tritium Finishing Facility, was added

 The FY 2021 milestone, Provide the tooling and equipment, facility and infrastructure investments 

necessary to sustain the Microsystems Engineering, Science, and Applications Complex, was added 

 The FY 2021 milestone, Obtain CD-1 (Approve Alternative Selection and Cost Range) for the Power 

Sources Capability Facility, was added 

 The FY 2021 milestone, Obtain CD-1 (Approve Alternative Selection and Cost Range) for the 

Savannah River Plutonium Processing Facility, was added 

 The FY 2021 milestone, Obtain CD-1 (Approve Alternative Selection and Cost Range) for the 

Plutonium Pit Production Project (LANL), was added 

 The FY 2022 milestone, Obtain Lithium Processing Facility CD-2/3 (Approve Performance 

Baseline/Approve Start of Construction), was postponed to FY 2024 

 The FY 2022 milestone, Obtain CD-0 (Approve Mission Need) for the Tritium Development 

Laboratory, was added 

 The FY 2023 milestone, Obtain CD-1 (Approve Alternative Selection and Cost Range) for the 

Domestic Uranium Enrichment production facility, was postponed to FY 20247

 The FY 2024 milestone, Obtain CD-2/3 (Approve Performance Baseline/Approve Start of 

Construction) for the Tritium Finishing Facility, was added 

 The FY 2025 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the

High Explosives (HE) Science and Engineering Facility, was added 

 

7 Depending on the outcome of the Analysis of Alternatives, DOE/NNSA may begin deployment of an enrichment pilot plant prior 

to obtaining CD-1 approval. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-10 

 The FY 2025 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

HE Synthesis, Formulation, and Production Facility for future LEPs, was added 

 The FY 2026 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for Power 

Sources Capability, was added 

 The FY 2026 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

Energetics Material Characterization, was added8

 The FY 2027 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

Lithium Processing Facility), was postponed to FY 2031 to meet mission requirements 

 The FY 2029 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

Chemistry and Metallurgy Research Replacement Project, was added 

 The FY 2031 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

Tritium Finishing Facility, was added 

 The FY 2037 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for the 

Heterogeneous Integration Facility, was added 

 The FY 2039 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for 

Neutron Generator Enterprise Consolidation, was added 

 The FY 2039 milestone, Obtain CD-4 (Approve Start of Operations or Project Completion) for 

Domestic Uranium Enrichment, was changed to FY 2040 as DOE/NNSA has identified additional 

quantities of material, pushing off the need date by one year 

The milestones from last year’s SSMP anticipated to be completed in FY 2020 are: 

 Re-establish lithium chloride conversion and purification process 

 Complete Analysis of Alternatives for domestic uranium enrichment

 Obtain Technology Readiness Level 7 (TRL-7) for selected technologies for insertion into the 

Lithium Processing Facility (previously scheduled in FY 2021) was accelerated to FY 2020 as the 

program is seeking an opportunity for TRL-6 technology insertion into the schedule with the least 

amount of impact 

There were no substantive changes to the remainder of the Production Modernization milestones 

included in Figure 5–5. 

 

8 DOE/NNSA obtained CD-0, Achieve Mission Need, approval for the Power Sources Capability (PSC) facility in FY 2019 and for the 

Energetic Materials Characterization (EMC) facility in FY 2020. DOE/NNSA is working toward CD-4, Approve Start of Operations 

or Project Completion, approval for both projects in FY 2026 based on the clearly defined capability gap and mission need. The

AoA process for EMC, Conceptual Design for PSC, and subsequent cost estimates for both will inform future budget planning 

profiles. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-11 

Figure 5–5. Key milestones for Production Modernization 

5.4 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 the need for additional nuclear explosive testing, 

previously within Research Development, Test, and Evaluation (RDT&E). SRT&E encompasses six major 

subprograms that support science-based stockpile stewardship, stockpile modernization, and continued 

assessment of the stockpile without additional explosive nuclear testing: (1) Assessment Science; 

(2) Engineering and Integrated Assessments; (3) Inertial Confinement Fusion (ICF); (4) Advanced 

Simulation and Computing (ASC); (5) Weapons Technology and Manufacturing Maturation; and 

(6) Academic Programs. 

Budget 

The budget request for SRT&E increased 9 percent from the FY 2020 enacted budget (comparable) and is 

illustrated in Figure 5–6. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-12 

Figure 5–6. Funding schedule for Stockpile Research, Technology, and Engineering, 

FY 2020 – FY 2025 

FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

5.4.2.1 Assessment Science (previously 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 

(previously Advanced Radiography); (4) Secondary Assessment Technologies; (5) Enhanced Capabilities 

for Subcritical Experiments (ECSE); and (6) Hydrodynamic and Subcritical Experiment Execution Support.9

 

The base Subcritical Experiments (SCE) program moved from Dynamic Materials Properties to Primary 

Assessment Technologies to gain efficiencies and make the SCE program easier to execute. 

The budget request for Assessment Science increased to address cost growth for planned FY 2025 

completion of the Advanced Sources and Detectors Major Item of Equipment for the ECSE project to meet 

W80-4 LEP and W87-1 Modification Program needs. Funding also supports the execution of experiments 

for plutonium aging assessment using platforms such as the Joint Actinide Shock Physics Experimental 

 

9 Hydrodynamic and Subcritical Experiment Execution Support includes some scope and funding from Weapon Technology 

Development (previously Research & Development Certification & Safety). 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-13 

Research gas gun, focused material studies in support of Plutonium Modernization, direct cast of 

uranium qualification, and investigations of aged canned subassemblies to aid in warhead and production 

modernization. 

5.4.2.2 Engineering and Integrated Assessments (previously Engineering) 

Engineering and Integrated Assessments supports system-agnostic survivability in present and future 

stockpile-to-target sequences. It also enables a responsive nuclear deterrent through collaborative 

partnerships, proactive integration, and assessments. This program includes seven subprograms: 

(1) Archiving and Support;10 (2) Delivery Environments; (3) Weapons Survivability (previously Nuclear 

Survivability); (4) Studies and Assessments;11 (5) Aging and Lifetimes (previously Enhanced Surveillance); 

(6) Stockpile Responsiveness; and (7) Advanced Certification and Qualification (previously Advanced 

Certification). 

The budget request for Engineering and Integrated Assessments increased to continue development of 

engineering options for future weapon systems as well as supporting continued capabilities for the 

survivability of weapons in normal, abnormal, and hostile environments. It also provides the engineering 

foundation for engineering analyses in combined environments to increase safety and performance; 

continues investments in advanced diagnostics for non-destructive surveillance, increasing knowledge 

and reducing sustainment costs; studies aging effects and helps determine the lifetimes of stockpile 

components; accelerates the nuclear weapons life cycle; and explores new certification and qualification 

approaches for new and reused weapon components to reduce technical risk and time to field. 

5.4.2.3 Inertial Confinement Fusion (previously Inertial Confinement Fusion Ignition and 

High Yield) 

ICF provides expertise and capabilities in high energy density (HED) science, a key component of sciencebased stockpile stewardship. The program includes three subprograms: (1) HED and Ignition Science for 

Stockpile Applications (previously Ignition and Other Stockpile Programs and Pulsed Power ICF); (2) ICF 

Diagnostics and Instrumentation (previously Diagnostics, Cryogenics, and Experimental Support); and 

(3) Facility Operations (previously Facility Operations and Target Production). 

The budget request for ICF addresses three areas: 

 Support implementation of key findings from the ICF 2020 program reviews 

 Focus ignition science campaigns on driving down barriers to understand necessary steps to 

demonstrate ignition 

 Support full operations at the National Ignition Facility, the Z pulsed power facility, and the 

Omega Laser Facility to enable execution of the highest-priority weapons-relevant experiments 

5.4.2.4 Advanced Simulation and Computing 

ASC provides high-end simulation capabilities (e.g., modeling codes, computing platforms, and supporting 

infrastructure) to meet stockpile stewardship requirements. The program includes six subprograms: 

(1) Integrated Codes; (2) Physics and Engineering Models; (3) Verification and Validation; (4) Advanced 

 

10 Archiving and Support includes some scope and funding from Research and Development Support, and Research and 

Development Certification and Safety. 

11 Studies and Assessments funds all future budget requests for pre-Phase 6.1 assessments, studies, and other activities. This 

new control level was directed by Congress in the Energy and Water Development and Related Agencies Appropriations Act of 

2020 with the purpose of improving oversight and visibility of all pre-Phase 6.1 activities by containing them under a single control 

level. It is unfunded in the FY 2021 budget request. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-14 

Technology Development and Mitigation; (5) Computational Systems and Software Environment; and 

(6) Facility Operations and User Support. 

The budget request for ASC decreases in FY 2021 due to suspension of new development of all nextgeneration simulation capabilities while mature next generation code development and computing 

technologies are transitioned into the base program and older code and software tool packages are 

replaced. 

5.4.2.5 Weapons 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. It comprises three subprograms: (1) Surety Technologies (previously Enhanced Surety); 

(2) Weapon Technology Development;12 and (3) Advanced Manufacturing Development (previously 

Additive Manufacturing and Component Manufacturing). 

The budget request for Weapons Technology and Manufacturing Maturation increased to support the 

maturation of technologies, materials, and manufacturing processes for future weapon systems to reduce 

technical risk and time to field, including direct cast of uranium. The technology and production options 

are being developed on a timeline to ensure that they are sufficiently mature to be viable options for 

warhead modernization activities, with a goal of significantly reducing the time and technical risk of 

warhead and complex modernization. The program advances R&D of additively-manufactured (AM) 

feedstock and deposition processes, as well as qualification of AM parts and components. The increase 

also funds the next High Operational Tempo Sounding Rocket Flight Test (HOT SHOT) demonstration (see 

Chapter 3, Section 3.4.3.1), which will shorten the development, testing, and qualification timeline for 

new components and technologies and supports development of new, safer initiation technologies. 

5.4.2.6 Academic Programs (previously Academic Alliances and Partnerships) 

Academic Programs support students pursuing an education in science and engineering disciplines of 

critical importance to DOE/NNSA including: nuclear science, radiochemistry, the study of materials at 

extreme conditions, HED science, advanced manufacturing, and computational science. Through this 

support, the program facilitates a personnel pipeline for the enterprise, particularly in areas with little to 

no commercial interest. 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 budget request for Academic Programs meets growing needs to assure a strong and diverse base of 

national expertise and educational opportunities in specialized technical areas that uniquely contribute 

to modernization and stewardship of the nuclear stockpile. 

Key Milestones 

DOE/NNSA must meet key milestones in order to successfully develop and maintain the critical 

capabilities, tools, and processes needed to support science-based stockpile stewardship, refurbishment, 

and continued assessment of the stockpile without additional explosive nuclear testing. Key milestones 

for SRT&E are illustrated in Figure 5–7. As a result of the budget structure change, milestones that were 

previously shown separately in the former RDT&E sections have been consolidated into a single figure for 

 

12 Weapon Technology Development includes some of the scope and funding from Research and Development Support and 

Research and Development Certification and Safety. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-15 

SRT&E. Several lower-level milestones were removed for consistency with the level of detail in the other 

milestone sections. Major changes from last year’s plan are: 

 The FY 2021 milestone, Obtain CD-3A approval for long-lead ECSE procurements, was modified to 

Obtain CD-3A (Approve Long-Lead Item Procurements) for ASD-Scorpius

 The FY 2021 milestone, Accept ATS-3/Crossroads computing platform, was modified to reflect 

acceptance in FY 2022 

 The FY 2022 milestone, Complete Red Sage and Nimble subcritical experiment campaigns, was 

added 

 The FY 2023 milestone, Design and demonstrate a light weight, modular weapon system 

architecture, was added 

 The FY 2024 milestone, Provide a pulsed neutron source that supports radiographic and reactivity 

measures, was modified to Field a neutron source and detectors to obtain subcritical experiment 

reactivity measurements

 The FY 2023 milestone, Complete assembly of a 10-megaelectronvolt (MeV) neutron imaging 

machine at LLNL for plant installation was modified to Complete assembly of a 7-MeV neutron 

imaging machine at LLNL for plant installation by FY 2025 

 The FY 2025 milestone, Establish sustainable ECSE capability at the Nevada National Security Site, 

was modified to Obtain CD-4 (Approve Start of Operations or Project Completion) for ASD-Scorpius

 The FY 2026 milestone, Conduct first test using Enhanced Capabilities for Subcritical Experiments, 

was added 

The milestone from the last SSMP anticipated to be completed in FY 2020 is: 

 Complete Exascale Class Computer Cooling Equipment (EC3E) project (previously listed for 

completion in FY 2021)

There were no substantive changes to the remainder of the SRT&E milestones included in Figure 5–7. 

Figure 5–7. Key milestones for Stockpile Research, Technology, and Engineering 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-16 

5.5 Infrastructure and Operations 

Infrastructure and Operations maintains, operates, and modernizes the DOE/NNSA infrastructure in a 

safe, secure, and cost-effective manner to maximize return on investment, enable program results, and 

reduce enterprise risk. The program also plans, prioritizes, and constructs state-of-the-art facilities, 

infrastructure, and scientific tools for the nuclear security enterprise. It includes: (1) Operations of 

Facilities; (2) Safety and Environmental Operations; (3) Maintenance and Repair of Facilities; and 

(4) Recapitalization. 

The success of DOE/NNSA’s unique national security missions is dependent upon safe, reliable, and 

modern infrastructure. However, the current state of DOE/NNSA’s infrastructure poses increasing risk to 

availability, capacity, and reliability for Weapons Activities capabilities, as well as the safety of the 

workforce, the public, and the environment. Upgrading or replacing aging facilities will require significant 

and sustained investment. 

Budget 

The budget request for Infrastructure and Operations increased 37 percent from the FY 2020 enacted 

budget (comparable) and is illustrated in Figure 5–8. 

Figure 5–8. Funding schedule for Infrastructure and Operations, FY 2020 – FY 2025 

FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

5.5.2.1 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 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. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-17 

The budget request for Operations of Facilities increased to support 30 pits per year production capability 

at LANL and additional leased space at KCNSC to meet warhead modernization schedules. 

5.5.2.2 Safety and Environmental Operations 

As a part of the FY 2021 budget request, Nuclear Materials Integration (NMI) moved from Directed 

Stockpile Work to Infrastructure and Operations. This realignment also includes funding realigned from 

the Material Recycle and Recovery program to NMI to continue support to the Material Managers at the 

sites currently providing NMI. 

The budget request for Safety and Environmental Operations increased to support Long-Term 

Stewardship remedial activities associated with the Pantex groundwater contamination plume, which has 

migrated offsite and affected neighboring private properties. It also addresses packaging increases to 

support pit production efforts at LANL. 

5.5.2.3 Maintenance and Repair of Facilities 

The budget request for Maintenance and Repair of Facilities increased to support 30 pits per year 

production at LANL and to implement the Nuclear Posture Review infrastructure modernization plan. It 

supports current maintenance staffing levels to maintain and preserve facilities in a condition suitable to 

meet an increasing mission demand. 

5.5.2.4 Recapitalization 

Recapitalization is comprised of: (1) Infrastructure and Safety, (2) Capability Based Investments, and 

(3) Planning for Programmatic Construction (Pre-CD-1), a new subprogram. It funds minor construction 

projects, capital equipment, planning, Other Project Costs for Infrastructure and Operations-funded lineitem construction projects, and deactivation and disposal of excess infrastructure. 

The budget request for Recapitalization increased to meet 30 pits per year production capability at LANL, 

warhead modernization schedules at KCNSC, new office and laboratory space requirements to 

accommodate 9,000 additional staff, and to implement the 2018 Nuclear Posture Review infrastructure 

modernization requirements. It also funds new programmatic equipment recapitalization requirements 

to support the W87-1 Modification Program and W80-4 LEP. The Planning for Programmatic Construction 

(Pre-CD-1) subprogram consolidates funding to the planning activities necessary to approve mission need 

and approve alternative selection and cost range for a portfolio of mission needs and related project 

proposals at multiple DOE/NNSA sites: Power Sources Capability, SNL; Combined Radiation Effects 

Survivability Testing, SNL; Next Generation LEP Component Fabrication Facility, LLNL; Kauai Test Facility 

Launch Sustainment, SNL-HI; and Energetic Materials Characterization, LANL. 

5.5.2.5 Construction 

In the new budget structure, line-item construction projects are categorized as either Programmatic 

Construction or Mission-Enabling Construction. 

The budget request for Programmatic Construction includes funding in FY 2021 for: 

 Lithium Processing Facility, Y-12 

 Tritium Finishing Facility, SRS 

 Exascale Computing Facility Modernization Project, LLNL 

 U1a Complex Enhancements Project, Nevada National Security Site 

 TA-55 Reinvestment Project, Phase 3, LANL 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-18 

 HE Science and Engineering Facility, Pantex 

 HE Synthesis, Formulation and Production, Pantex 

 Transuranic Liquid Waste Facility, LANL 

 Uranium Processing Facility, Y-12 

 Chemistry and Metallurgy Research Replacement Project, LANL 

The budget request for Mission-Enabling Construction includes funding in FY 2021 for: 

 138-kilovolt Power Transmission System Replacement, Nevada National Security Site 

 Emergency Operations Center, LLNL 

 Emergency Operations Center, SNL 

Additional information on planned infrastructure investments can be found in Chapter 4, “Infrastructure 

and Workforce.” 

Key Milestones 

Key milestones for Programmatic Construction are shown in the relevant program sections, as many of 

the capabilities depend on completion of line-item projects to execute their designed mission. Schedules 

for the highest-priority Programmatic and Mission-Enabling project proposals are displayed in 

Figures 4–2 through 4–4. Projects proposed within the FYNSP include higher-fidelity estimates; some 

planned projects in the out-years may convert to alternative strategies once each respective Analysis of 

Alternatives is completed. 

Per the National Defense Authorization Act for Fiscal Year 2018, DOE/NNSA established the Infrastructure 

Modernization Initiative (IMI) program to reduce deferred maintenance (DM) and repair needs by no less 

than 30 percent by 2025. The IMI will be carried out under the current budget structure by the 

Recapitalization: Infrastructure and Safety and Maintenance and Repair of Facilities programs. The initial 

plan was transmitted to Congress in September 2018. 

Infrastructure Maintenance and Recapitalization Investments 

As part of the IMI, DOE/NNSA has deployed 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 replacement plant value (RPV) of DOE/NNSA’s facilities. Using BUILDER-based 

calculations provides a more accurate and transparent understanding of DOE/NNSA’s infrastructure. The 

DM costs are tied to the RPV (it costs more to repair a more expensive facility); therefore, as expected, 

DM increased with the deployment of the new approach. As depicted in Table 5–2, the ratio of DM to 

RPV has decreased, which is an indication that recent investments have been successful. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-19 

Table 5–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant Value 

Metric FY 2017 FY 2018 FY 2019 

RN $5.2B $5.1B $8.9B 

DM $2.5B $2.5B $4.8B 

RPV $52.4B $55B $124.3B 

RN/RPV Ratio 9.92% 9.27% 7.16% 

DM/RPV Ratio 4.80% 4.63% 3.85% 

RN = Repair Needs 

DM = Deferred Maintenance

RPV = Replacement Plant Value

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 RPV) derived from the DOE Real Property Asset Management Plan and associated 

guidance. To address these benchmark shortfalls, DOE/NNSA has increased recapitalization investments 

by $236 million from FY 2020 to FY 2021. Recapitalization continues to include deactivation and 

demolition of excess and underutilized facilities to reduce the NNSA footprint. Maintenance investments 

reflect an increase of $342 million from FY 2020 to FY 2021. Overall funding for maintenance has grown 

significantly, but appropriately, over the last several years. This increase will support current maintenance 

staffing levels to maintain and preserve facilities in a condition that is 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 2021 DOE/NNSA infrastructure maintenance and recapitalization investments 

FY 2019 FY 2020 FY 2021 

Replacement Plant Value (RPV) ($B) 124.3 125.3 126.3

Maintenance 

Benchmark 

2 – 4% RPV

Infrastructure & Safety Maintenance Investments ($K) 515,000 456,000 792,000 

Other NNSA Maintenance Investments (direct and indirect funded) ($K) 284,922 298,008 304,266 

Total NNSA Maintenance Investments (SK) 799,922 754,008 1,096,266 

Maintenance as % RPV 0.64% 0.60% 0.87% 

Recapitalization 

Benchmark 

1% 

Infrastructure & Safety Recapitalization Investments ($K) 450,000 447,657 670,000 

Other NNSA Recapitalization Investments ($K) 109,057 135,341 149,117 

Total NNSA Recapitalization Investments ($K) 559,057 582,998 819,117 

Recapitalization as % RPV 0.45% 0.47% 0.65% 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-20 

5.6 Other Weapons Activities 

Budget 

The funding schedule for Other Weapons Activities is illustrated in Figure 5–9. 

Figure 5–9. Funding schedule for Other Weapons Activities, FY 2020 – FY 2025 

Secure Transportation Asset 

Secure Transportation Asset (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. 

5.6.2.1 FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

The budget request for Operations and Equipment increased 44 percent due to continued design, testing, 

and assembly of the Mobile Guardian Transporter (MGT), upgrade/redesign of the Tractor Control Unit, 

and life-cycle replacement of aircraft. 

The budget request for Program Direction increased 15 percent to sustain and maintain the manpower to 

meet requirements and support mission capacity, as well as to support an increase in workers’ 

compensation claims (resulting from a non-mission accident), travel, and cost of inflation. 

5.6.2.2 Key Milestones 

Aging transportation assets must be replaced to meet and maintain convoy safety and security 

requirements. The STA milestones illustrated in Figure 5–10 will enable DOE/NNSA to support evolving 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-21 

transportation requirements for the current and future stockpile. There are two changes from last year’s 

plan: 

 The FY 2020 milestone, Design and begin production of the next Generation Armored Tractor (T4) 

and Escort Vehicle (EV4), was postponed to FY 2021 due to changes in contract requirements that 

were based on the original procurement plan 

 The FY 2020 milestone to award the contract for EV4 was not completed in FY 2020 due to 

changes in contract requirements and COVID-19 restrictions. The contract award is projected to 

be completed by the third quarter FY 2021, based on the EV4 Master Schedule 

There were no substantive changes to the remainder of the STA milestones illustrated in Figure 5–10. 

Figure 5–10. Key milestones for Secure Transportation Asset

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. 

Together, this approach protects DOE/NNSA’s facilities, special nuclear material (SNM), employees, key 

networks, and information resources. 

5.6.3.1 FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

The budget request for Defense Nuclear Security (DNS) increased based on additional security 

requirements associated with growth across the nuclear security enterprise, including plutonium pit 

production efforts. The additional costs also complete implementation and sustain operation of counter 

unmanned aircraft systems (CUAS) at sites possessing Category 0/I SNM, as well as support the Physical 

Security Center of Excellence and the Center for Security Technology, Analysis, Response and Testing. The 

funding also supports planned equipment lifecycle replacements across the enterprise, and implement 

upgrades to NNSA’s Special Access Program classified network. 

Funding for the DNS construction project, 17-D-710, the West End Protected Area Reduction, decreased 

due to receipt of funding in FY 2020. 

5.6.3.2 Key Milestones 

The 10-Year Physical Security Systems Refresh Plan, which was sent to Congress in August 2017, is being 

implemented through the Security Infrastructure Revitalization Program (SIRP). The SIRP refreshes 

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 illustrated in Figure 5–11 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:
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-22 

 The FY 2024 milestone, Complete Los Alamos National Laboratory Perimeter Intrusion Detection 

and Assessment System (PIDAS), was added 

 The FY 2025 milestone, Complete Savannah River Site PIDAS, was added 

 The FY 2026 milestone, Complete Pantex PIDAS physical security system components and 

infrastructure refresh for Zone 12, was updated 

 The FY 2028 milestone, Complete Pantex PIDAS physical security system components and 

infrastructure refresh for Zone 4, was added

 The FY 2030 milestone, Complete first iteration of SIRP, was postponed to FY 2035 

The milestones from the last SSMP anticipated to be completed in FY 2020 are: 

 Complete deployment of Argus Security System as the standard access control and alarm system 

at all Category 1 SNM sites 

 Complete CUAS implementation and sustain operations at sites possessing Category 0/1 quantities 

of SNM

 Complete Design Basis Threat analysis for remaining NNSA Category 1 sites

There were no substantive changes to the remainder of the DNS milestones included in Figure 5–11. 

Figure 5–11. Key milestones for Defense Nuclear Security 

Information Technology and Cybersecurity 

IT and Cybersecurity is focused on developing integrated IT initiatives that provide an effective technology 

infrastructure and support to the nuclear security enterprise shared services. These initiatives will 

fundamentally redesign DOE/NNSA IT environments to provide a more secure and agile set of capabilities 

including unified communication, agile cloud infrastructure, and next-generation collaboration services 

across the nuclear security enterprise. 

5.6.4.1 FY 2021 Budget Request Compared to FY 2020 Enacted Budget 

The budget request for IT and Cybersecurity increased 25 percent to continue planned modernization 

efforts. The budget increase assures that DOE/NNSA can meet requirements necessary to sustain 

continuous enhancement of cybersecurity and IT operations. 

As DOE/NNSA mission requirements expand in scope, complexity and budget, IT and Cybersecurity 

programs require modernization, expansion, and innovation. Increases in the IT and Cybersecurity budget 
Department of Energy/National Nuclear Security Administration | December 2020 

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are at a level that implements strategic protections. Cybersecurity is a defense/deterrence mechanism 

and a powerful tool. In the evolving threat environment, DOE/NNSA must maintain an aggressive 

approach to cyber defense capabilities protecting information, systems, and networks on which 

DOE/NNSA depends for mission support and execution. 

5.6.4.2 Key Milestones 

The milestones in Figure 5–12 are necessary steps toward achieving a fully modernized IT infrastructure 

and cybersecurity posture for the nuclear security enterprise. Changes from last year’s plan are: 

 The FY 2021 milestone, Develop phase II system architecture for modernizing the Enterprise Secure 

Computing (ESC) environment, was added 

 The FY 2021 milestone, Implement special network access, was added 

 The FY 2021 milestone, Implement the DOE/NNSA Application Modernization Strategy, was added

 The FY 2021 milestone, Implement a Telecommunications Security Program within DOE/NNSA, 

was added

 The FY 2021 milestone, Complete the modernization of the Information Assurance Response 

Center (IARC) cybersecurity infrastructure, was added

The milestones from the last SSMP anticipated to be completed in FY 2020 are: 

 Complete deployment of a new sensor platform across all DOE/NNSA sites 

 Complete LLNL Phase I of hybrid cloud platform for the Enterprise Secure Computing (ESC) cloud 

environment 

 Complete SNL Phase I of hybrid cloud platform for ESC cloud environment testing 

 Establish East Coast Data Center for secondary hybrid cloud platform for ESC cloud environment 

 Implement Phase I of IT Modernization Plan 

There were no substantive changes to the remainder of the IT and Cybersecurity milestones illustrated in 

Figure 5–12. 

Figure 5–12. Key milestones for Information Technology and Cybersecurity 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-24 

5.7 Budget Projections Beyond FY 2025 

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 5.8). 

Basis for Budget Projections 

For most of Weapons Activities, the FY 2021 – FY 2025 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 management and operating (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 

5.7.3. The budget estimates for FY 2026 and beyond reflect the costs of continuing the program of record 

described in this SSMP while sustaining and enhancing the Weapons Activities capabilities that are 

essential to executing the program of record. 

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.13 For these cost projections, 

such as for Stockpile Sustainment, an escalation factor of three percent was applied to account for annual 

labor rate increases at M&O sites, which are typically higher than inflation rates. 

Some portions of the program will not proceed at the same level of effort from FY 2026 through FY 2045. 

This applies primarily to Stockpile Major Modernization programs and major programmatic construction 

projects. The estimates and the basis for each of these elements of the Weapons Activities portfolio are 

described in these next sections. 

Sustaining the Current Stockpile 

Costs associated with Stockpile Sustainment include warhead-specific assessment activities, limited life 

component exchanges, required and routine maintenance, safety studies, periodic repairs, resolution and 

timely closure of significant finding investigations, military liaison work, and surveillance for continued 

safety, security, and effectiveness of the stockpile. These costs are incurred every year that a weapon is 

in the stockpile and can vary based on the number of warheads or types of warheads in the stockpile. 

DOE/NNSA is considering developing a new cost-estimating strategy to appropriately account for these 

variables. For the purpose of this SSMP, Stockpile Sustainment program costs are projected using the 

same escalation factor as other level of effort programs. 

Stockpile Major Modernization 

Stockpile Major Modernization programs have the goal of extending the lives of warheads for several 

more decades. Figure 2–1 in Chapter 2, “Managing the Stockpile,” 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 

 

13 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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Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-25 

expert judgment) to those using bottom-up models (deterministic, unit cost, and activity-based), 

depending on where the warhead program is in the Phase 6.x Process. 

5.7.3.1 Cost Estimates across the Phase 6.x Process

Cost estimates for the B61-12 LEP, W88 Alt 370, W80-4 LEP and W87-1 Modification Program follow the 

Phase 6.x Process.

14 Figure 5–13 delineates the governing cost estimate type for each phase of the 

Phase 6.x Process. DOE/NNSA works in conjunction with DoD and M&O partners to develop, refine, and 

update the estimates throughout the Phase 6.x Process. 

Figure 5–13. Cost estimates across the Phase 6.x Process

Prior to 2020, DOE/NNSA published a Defense Programs independent cost estimate for each system in 

the SSMP. Under the current reorganization, the DOE/NNSA Office of Management and Budget, Office of 

Analysis and Evaluation continues to develop and publish these Management and Budget planning cost 

estimates (Management and Budget cost estimates) for the SSMP.15 These cost estimates can be initiated 

at very early design maturity, often well before Phase 6.1 [Concept Assessment], and are planning 

estimates for alternatives analysis, early programming, and budget deliberations. Management and 

Budget Stockpile Major Modernization planning cost estimates are: 

 Performed by an organization separate from the Federal program office16

 Based on a known scope and cost uncertainty at the time and updated annually for the SSMP17 

 Inclusive of both warhead modernization program (development and production) and nonwarhead modernization program line-item costs that are critical to program success (namely 

Other Program Money and DoD costs)18

 Unconstrained by future budget availability, which may differ from future budget requests 

 

14 The Phase 6.x Process is based on the Joint Nuclear Weapons Life-Cycle Phases developed in coordination with DoD. In the 

Joint Nuclear Weapons Life-Cycle Phases, Phase 6 refers to “Quantity Production and Stockpile Maintenance & Evaluation.” 

DOE/NNSA has followed the Phase 6.x Process for planning Stockpile Major Modernization programs to date. 15 Under the current reorganization, all independent cost estimates will be conducted by the Office of Cost Estimating and 

Program Evaluation. 

16 GAO extolls the value of cost estimates using a different methodology and the potential benefit to decision-makers in the GAO 

Cost Estimating and Assessment Guide. 17 Planning estimates assume scopes that are in line with current policy objectives (such as a commitment to surety upgrades) in 

addition to extending the warhead life. The Nuclear Weapons Council approves the specific scope for the weapon modernization 

program based on the alternatives developed during Phase 6.2. 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. 18 In estimating the cost of a warhead modernization program, the weapon programs depend on an adequately funded base of 

other DOE/NNSA capabilities, are incremental to that base, and reflect both each program’s budgeted line item and increments 

to other critical activities (such as early-stage technology maturation [called Other Program Money]). As the overall program 

integrator, the Federal Program Manager identifies the funding streams needed for the program to be successful. 
Department of Energy/National Nuclear Security Administration | December 2020 

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These cost estimates are enumerated in the SSMP until the Weapon Design and Cost Report (WDCR) is 

approved. The estimate methodology is described in more detail in Section 5.7.3.2. 

The WDCR is currently developed by the program team responsible for the warhead modernization 

program 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 (Development 

Engineering). Once approved by the Nuclear Weapons Council the WDCR becomes the basis for the 

Selected Acquisition Report (SAR) to Congress that starts on entry in to 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 and represents a more definitive cost estimate than either the MB cost estimate 

or WDCR. The NNSA Administrator approves a program baseline, including the WDCR, 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 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 Phases 6.3, 6.4 (Production Engineering), and 6.5 

(First Production). 

5.7.3.2 Management and Budget Cost Estimating Methodology 

The Management and Budget cost estimates for Stockpile Major Modernization programs are developed 

four ways: 

 Performed using a “top-down” analogy method that is consistent with early-stage planning19

 Informed by ongoing and past program costs (such as the development of the W76-1, B61-12, 

W88 Alt 370, and production of the W76-1) and the evaluation of the relative complexities of 

future systems20

 Based on time-phased development21 costs using a standard profile22 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 Phases 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 

 

19 Additional detail on the cost estimating methodology of Management and Budget cost 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). 

20 These program and subject matter experts evaluate the relative scope complexity between the complete W76-1 and nearcomplete B61-12 and W88 Alt 370 compared to each planned future warhead modernization program, which aids in providing a 

cost estimate range based on underlying technical and cost uncertainties. 

21 Development costs include all national nuclear security laboratory and production development costs, which is how DoD 

defines RDT&E and is consistent with Rayleigh profile usage in cost estimating. 

22 See Lee, David. The Cost Analyst’s Companion, 3rd ed., McLean, VA: Logistics Management Institute, McLean, VA. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-27 

future systems with little design definition were based on the W87-1 estimate with an expanded range 

due to uncertainty in scope and quantities and the escalation rate so far in the future. 

5.7.3.3 Current Estimates 

Figures 5–15 through 5–18 and Tables 5–5 through 5–13 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 SSMP. Additional details on the 

basis for each estimate are provided for each individual program in Sections 5.7.3.4 through 5.7.3.11. 

Table 5–4. Cost estimates for life extension programs and major alterations 

within the 25-year program of record23

Life Extension Program, Major 

Alteration, or Modification Program Type of Cost Estimate 

Total Estimated Cost 

(FY 2020 dollars in billions) 

Total Estimated Cost 

(then-year dollars in billions) 

W76 LEP BCR/SAR 4.2 3.5 

W76-2 Modification Program BCR/SAR 0.075 0.075 

B61-12 LEP BCR/SAR24 8.4 8.3 

W88 Alt 370 BCR/SAR25 2.9 2.8 

W80-4 LEP WDCR/SAR26 9.7 11.0 

W87-1 Modification Program MB Cost Estimate 11.1 13.8 

W93 MB Cost Estimate 14.2 18.2 

Future Strategic Land-Based Warhead MB Cost Estimate 14.2 19.2 

Future Strategic Sea-Based Warhead MB Cost Estimate 14.2 20.5 

B61 Follow-On MB Cost Estimate 14.2 26.3 

BCR/SAR = Baseline Cost Report/Selected Acquisition Report 

MB = Management and Budget

WDCR = Weapon Design and Cost Report

A summary table with high, low, and nominal (proposed budget or BCR/SAR value) estimates for 

DOE/NNSA and DoD, in both constant FY 2020 and then-year dollars, is listed for each Stockpile Major 

Modernization program. Where appropriate, the tables also include pre-SAR values for pre-Phase 6.2 

costs.27 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 85 percent (p85) for the B61-12, 

W88 Alt 370 and W80-4, but was increased to the 90th percent (p90) for the W87-1 to reflect the greater 

uncertainty. 

 

23 SAR and WDCR values are provided when available. For programs that only have a Management and Budget cost estimate, 

the proposed budget is provided. Tables 5-5 through 5–13 provide values for a high and low estimate range, in addition to the 

SAR, WDCR, or Management and Budget cost estimate totals. Due to the differing types of cost estimates, the accuracy of these 

total program cost estimates varies. 

24 Defense Programs is still finalizing the B61-12 BCR updates. The values represent the current assessed values, but may change

for next year’s SSMP as a result. 

25 Defense Programs is still finalizing the W88 Alt 370 BCR updates. The values represent the current assessed values, but may 

change for next year’s SSMP as a result. 

26 Defense Programs initial annual SAR for the W80-4 was submitted to Congress in May 2020. The total program cost estimate 

is $11 billion in Then-Year-Dollars. The $107 million reduction compared to the WDCR reflects design simplifications and 

execution adjustments through FY 2026. 

27 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 

have later portions that extend beyond the published 25-year SSMP timeframe. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-28 

For early-stage programs using Management and Budget cost estimates (such as the W87-1 Modification 

Program), the figures and tables reflect the current proposed FYNSP budget and, for years beyond the 

FYNSP, 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 2021 

SSMP’s classified Annex provides additional information on production quantities. 

 The then-year Management and Budget cost estimates in the tables and figures are derived from 

constant-year estimates using the escalation rates in the Office of Management and Budget 

(OMB) Table 10.1.28 For years beyond the 6 years projected in Table 10.1, the escalation rate for 

the final year is used.29 The escalation rate used by the sites to produce the WDCRs and BCRs may 

differ from the OMB number used in the Management and Budget cost estimates. For example, 

official program office estimates may use escalation rates specific to each site and function, rather 

than a national 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, as the Nuclear Weapons Council may update and/or down-select 

design options and significantly impact the work scope and cost estimate. 

 Only the Management and Budget cost estimates include pre-Phase 6.2 costs. The WDCR and 

BCR/SAR estimates do not include these costs. 

5.7.3.4 W76 Life Extension Program (W76-1) Cost Estimate 

The W76-1 warhead last production unit was produced in December 2018 and was delivered to the Navy 

in April 2019. Remaining component production for life of program requirements are scheduled to 

complete in FY 2022. Table 5–5 represents the actual program cost. 

Table 5–5. Total actual cost for W76-1 Life Extension Program 

FY 2001 – FY 2019 

(dollars in billions) 

DOE/NNSA DoD 

FY 2020 Dollars Then-Year Dollars FY 2020 Dollars Then-Year Dollars 

SAR Total 4.2 3.5 N/A N/A 

SAR = Selected Acquisition Report 

5.7.3.5 W76-2 Modification Program Cost Estimate 

The DOE/NNSA laboratories and production facilities completed a compressed Phase 6.3 through 6.5 

process and are currently accomplishing Phase 6.6 activities. The remaining warhead production and 

deliveries are scheduled to complete in FY 2020. Table 5–6 represents the total estimated costs. 

Table 5–6. Total estimated cost for W76-2 Modification Program 

 

28 Available at https://www.whitehouse.gov/omb/historical-tables/. 

29 Recommendation from OMB Circular A-94, Guidelines and Discount Rates for Benefit-Cost Analysis of Federal Programs. 

FY 2019 – FY 2020 

(dollars in millions) 

DOE/NNSA DoD 

FY 2020 Dollars Then-Year Dollars FY 2020 Dollars Then-Year Dollars 

Total Cost 75 75 N/A N/A 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-29 

5.7.3.6 B61-12 Life Extension Program Cost Estimate 

The B61-12 LEP program is currently in Phase 6.4, Production Engineering. The program experienced an 

issue with commercial off-the-shelf (COTS) base metal electrode capacitors in late 2019, affecting six 

electrical assemblies that required rework, validation, and qualification testing. The new component and 

system validation scope, along with efforts to improve component producibility resulted in an increase of 

$673 million from the previous reported cost estimate of $7.6 billion. This new cost estimate is based on 

the analysis documented in an updated BCR to be issued at a future date. The overall program cost is now 

estimated at $8.3 billion (then-year dollars); these cost increases are being managed within the 

DOE/NNSA Stockpile Major Modernization portfolio. The B61-12 LEP is continuing to use Other Program 

Money for multi-system production process improvements. The costs of these related programs are 

estimated to be $648 million. The nominal values for development and production in Figure 5–14 and 

Table 5–7 reflect DOE/NNSA’s FY 2020 BCR update (to be released) and may change slightly as the BCR 

update is finalized and reconciled with DOE/NNSA’s Office of Cost Estimating and Program Evaluation’s 

independent cost estimate. 

Figure 5–14. B61-12 Life Extension Program cost from FY 2012 to completion30

Table 5–7. Total estimated cost for B61-12 Life Extension Program 

DOE/NNSA DoD 

Dollars in Billions FY 2020 Dollars Then-Year Dollars FY 2020 Dollars Then-Year Dollars 

Pre-SAR Cost 0.5 0.4 N/A N/A 

FY 2012 – FY 2026 

SAR Total 8.4 8.3 N/A N/A 

SAR Other Program Money Total 0.7 0.6 N/A N/A 

MB High Estimate a 9.8 9.7 0.2 0.2 

MB Low Estimate a 8.9 8.8 0.2 0.2 

MB = Management and Budget 

a Including Other Program Money 

SAR = Selected Acquisition Report 

 

30 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. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-30 

5.7.3.7 W88 Alt 370 Cost Estimate 

The W88 Alteration 370 Program, currently in Phase 6.4, Production Engineering, was scheduled to deliver 

the first production unit in the first quarter of FY 2020. Delivery of the system-level first production unit 

was formally rescheduled by the Nuclear Weapons Council for the fourth quarter of FY 2021 due to delays 

resulting from an issue with COTS base metal electrode capacitors used in three major components of the 

W88 Alt 370. DOE/NNSA completed a high-fidelity cost estimate (the BCR) in FY 2017 and is currently 

updating that cost estimate to include the recently completed bottom-up estimate updates for capacitoraffected components. While the other components remain in production, the capacitor replacement has 

resulted in a cost impact of $184 million to the program for a new total of $2.80 billion. 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 5–15 and Table 5–8 reflect the changes that will be 

included in the BCR update (to be released) and may change slightly as the BCR update is finalized and 

reconciled with DOE/NNSA’s Office of Cost Estimating and Program Evaluation’s independent cost 

estimate. 

Figure 5–15. W88 Alteration 370 (with conventional high explosive refresh) 

from FY 2013 to completion
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-31 

Table 5–8. Total estimated cost for W88 Alteration 370 

(with conventional high explosive refresh) Program 

Dollars in Billions 

DOE/NNSA DoD 

FY 2020 Dollars Then-Year Dollars FY 2020 Dollars Then-Year Dollars 

Pre-SAR Cost 0.1 0.1 N/A N/A 

FY 2013 – FY 2026 

SAR Total 2.9 2.8 N/A N/A 

SAR Other Program Money Total 0.2 0.2 N/A N/A 

MB High Estimate a 3.3 3.3 1.1 1.0 

MB Low Estimate a 3.2 3.0 1.1 1.0 

MB = Management and Budget 

a Including Other Program Money 

SAR = Selected Acquisition Report 

5.7.3.8 W80-4 Life Extension Program Cost Estimate 

In FY 2019, the W80-4 LEP completed the WDCR and entered Phase 6.3, Development Engineering, where 

the design will continue to be refined. The current cost estimates are displayed in Figure 5–16 and 

Table 5–9. This estimate (solid bars) reflects a decrease in the FYNSP from what was in the FY 2020 SSMP 

as a result of design simplifications with resulting savings applied to off-setting increased costs due to the 

capacitor change for the B61-12 and W88 Alt 370. This change will be represented in the next SAR. 

Figure 5–16. W80-4 Life Extension Program cost from FY 2015 to completion 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-32 

Table 5–9. Total estimated cost for W80-4 Life Extension Program 

DOE/NNSA DoD 

Dollars in Billions FY 2020 Dollars Then-Year Dollars FY 2020 Dollars Then-Year Dollars 

Pre-SAR Cost 0.9 1.0 N/A N/A 

FY 2012 – FY 2026 

SAR Total 9.7 11.0 N/A N/A 

SAR Other Program Money Total 0.2 0.2 N/A N/A 

MB High Estimate a 10.2 11.6 0.2 0.3 

MB Low Estimate a 8.6 9.8 0.1 0.1 

MB = Management and Budget 

a Including Other Program Money 

SAR = Selected Acquisition Report 

5.7.3.9 W87-1 Modification Program (formerly IW1) Cost Estimate 

In August 2018, the Nuclear Weapons Council authorized a restart of Phase 6.2 activities for the W87-1 

Modification Program, and the program is on track to support fielding of the Ground-Based Strategic 

Deterrent by FY 2030. In 2019, the Nuclear Weapons Council reviewed a series of surety architecture 

design options; to include a detailed cost, risk/benefit, and cost analyses before selecting a single surety 

option for W87-1. DOE/NNSA continues to evaluate other component design options and trades. In 

FY 2021, the W87-1 Modification Program will complete Phase 6.2, Feasibility Study and Design Options, 

and enter Phase 6.2A, Design Definition and Cost Study. The cost estimate in Figure 5–17 represents the 

latest projected program cost reflecting the single architecture Nuclear Weapons Council decision and is 

a reduction in cost from the high-complexity scope case published in the FY 2020 SSMP and 2019 

congressional report.31 The scope complexity and resulting cost estimate is also informed by a greater 

understanding of production complexity, system engineering and integration complexity due to 

interfacing with the Ground-Based Strategic Deterrent and the anticipated challenges of using new 

materials. The estimates in Figure 5–17 and Table 5–10 do not include costs associated with the 

production of plutonium pits for the W87-1 after the capability to produce 30 pits per year is 

demonstrated at LANL and 50 pits per year at SRS. Those costs are contained in Plutonium Modernization. 

 

31 W78 Replacement Program (W87-1): Cost Estimates and Use of Insensitive High Explosives, Report to Congress, 

December, 2018. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-33 

Figure 5–17. W87-1 Modification Program cost from FY 2019 to completion 

Table 5–10. Total estimated cost for W87-1 Modification Program 

5.7.3.10 W93 Cost Estimate 

The W93 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 of record. The W93 cost estimate (see Table 5–11) provides a planning estimate only. It is 

based on the W87-1 Modification Program, with increased uncertainty, since the W87-1 Modification 

Program most closely aligns with the safety and surety requirements for future weapon. It should not be 

inferred that the W93 will closely resemble the W87-1 Modification Program. This estimate will change 

as requirements and schedules are refined and will be updated in future versions of the SSMP. 

FY 2019 – FY 2037 

(dollars in billions) 

DOE/NNSA DoD 

FY 2020 

Dollars 

Then-Year 

Dollars 

FY 2020 

Dollars 

Then-Year 

Dollars 

MB High Estimate a 11.1 13.8 1.0 1.2 

MB Low Estimate a 9.0 10.7 0.9 1.1 

Proposed Budget N/A 12.3 N/A 1.1 

MB = Management and Budget 

a Including Other Program Money 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-34 

Table 5–11. Total estimated cost for W93 

Dollars in Billions 

DOE/NNSA DoD 

FY 2020 

 Dollars 

Then-Year 

Dollars 

FY 2020 

Dollars 

Then-Year 

Dollars 

MB High Estimate a 14.2 18.2 1.0 1.3 

MB Low Estimate a 9.6 11.8 0.9 1.2 

Proposed Budget N/A 15.0 N/A 1.2 

MB = Management and Budget 

a Including Other Program Money 

5.7.3.11 Future Strategic Missile Warhead Cost Estimate 

DOE/NNSA is also coordinating with DoD to define the appropriate ballistic missile warheads to support 

threats anticipated through 2030 and beyond, in accordance with the 2018 Nuclear Posture Review. The 

military capabilities required from the Future Strategic Land-Based Warhead and the Future Strategic SeaBased 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. In addition to these warheads, a replacement air-delivered 

warhead and submarine-launched warhead (for the W76-1/2) will be needed in the 2040s. 

The Future Strategic Missile Warhead cost estimates (see Table 5–12 and Table 5–13) 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 5–12. Total estimated cost for Future Strategic Missile – Land-Based Warhead 

Dollars in Billions 

DOE/NNSA DoD 

FY 2020 

Dollars 

Then-Year 

Dollars 

FY 2020 

Dollars 

Then-Year 

Dollars 

MB High Estimate a 14.2 19.2 1.0 1.3 

MB Low Estimate a 9.6 13.0 0.4 0.6 

Proposed Budget N/A 16.1 N/A N/A 

MB = Management and Budget 

a Including Other Program Money 

Table 5–13. Total estimated cost for Future Strategic Missile – Sea-Based Warhead 

Dollars in Billions 

DOE/NNSA DoD 

FY 2020 

 Dollars 

Then-Year 

Dollars 

FY 2020 

 Dollars 

Then-Year 

Dollars 

MB High Estimate a 14.2 20.5 1.0 1.4 

MB Low Estimate a 9.6 13.9 0.4 0.6 

Proposed Budget N/A 17.2 N/A N/A 

MB = Management and Budget 

a Including Other Program Money 

5.7.3.12 B61 Follow-On Cost Estimate 

The B61 Follow-On cost estimate (see Table 5–14) provides a planning estimate for a notional system 

based on the current B61-12 scope with increased uncertainty in design scope and quantities adjusted for 

out-year escalation. This estimate will change as requirements and schedules are refined and will be 

updated in future versions of the SSMP. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-35 

Table 5–14. Total estimated cost for B61 Follow-On 

Dollars in Billions 

DOE/NNSA DoD 

FY 2020 

Dollars 

Then-Year 

Dollars 

FY 2020 

 Dollars 

Then-Year 

Dollars 

MB High Estimate a 14.2 26.3 0.2 0.4 

MB Low Estimate a 10.0 18.5 0.2 0.3 

Proposed Budget N/A 22.4 N/A 0.3 

MB = Management and Budget 

a Including Other Program Money 

5.7.3.13 Summary of Cost Estimates 

Figure 5–18 represents a summary of cost estimate ranges for all presently known warhead 

modernization programs from FY 2020 through FY 2045 based on schedule assumptions that are subject 

to change. 

 

Figure 5–18. Total U.S. projected nuclear weapons life extension costs for 

FY 2020 – FY 2045 with high and low estimates (then-year dollars) 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-36 

Construction 

5.7.4.1 Cost Estimation for Capital Acquisitions 

In FY 2020, DOE/NNSA began publishing cost estimates for early-stage capital acquisitions.32 These early 

planning estimates, published as long as a decade or more before a project’s initial mission approval, 

primarily inform Weapons Activities’ long-term cost projections for programmatic construction and are 

supplemental to DOE acquisition requirements in DOE Order 413.3B. 

Notably, these cost estimates are: 

 Performed by an organization separate from the Federal program office33

 Performed using a top-down parametric method that is consistent with early-stage planning34

 Based on historic DOE/NNSA project schedules, costs, and project phasing 

 Based on current anticipated project scopes 

 Based on affordability analysis with total construction funding constrained 

 Updated annually for the SSMP 

Once a project begins the acquisition process, the approved cost estimate ranges at the CD-0 milestone 

(Mission Approval) 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, 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-2) or DOE’s Office of Project Management (post-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 

analyses of alternatives (AoAs). The assumed scope should be considered notional until the project 

reaches and defines performance baseline at CD-2. 

The cost estimation professional society, AACE International, has published a cost estimate classification 

system35 based on the scope definition of the project. DOE/NNSA has mapped the AACE International 

cost estimate classes to their most common uses for capital acquisitions.36 Table 5–15 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. 

 

32 Estimates developed independent of the program are a best practice identified by GAO and other professional organizations 

as a tool to objectively compare to program estimates and identify potential issues early. 33 The DOE/NNSA Office of Management and Budget, Office of Analysis and Evaluation performs the cost estimates on behalf of 

Defense Programs. 

34 GAO extolls the value of independent cost estimates using a different methodology and the potential benefit to decisionmakers in the GAO Cost Estimating and Assessment Guide. 35 AACE International Recommended Practice 18R-97, Cost Estimation Classification System as Applied in Engineering, 

Procurement and Construction for the Process Industries. 

36 DOE Guide 413.3-21A Cost Estimating Guide. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-37 

Table 5–15. 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 

L: -20 to -50 

H: +30 to +100 

Class 4 1 to 15 Alternative Selection (CD-1) Analysis of Alternatives, 

Conceptual Design

Equipment factored 

or parametric models 

L: -15 to -30 

H: +20 to +50 

Class 3 10 to 40 Project Baseline (CD-2) 

(low-risk projects) 

Preliminary Design Semi-detailed unit 

costs with assembly 

level line items 

Low: -10 to -20 

H: +10 to +30 

Class 2 30 to 75 Start of Construction 

(CD-3)/ Project Baseline 

(CD-2) (high-risk projects) 

Final Design Detailed unit cost 

with forced detailed 

take-off 

L: -5 to -15 

H: +5 to +20 

Class 1 65 to 100 Detailed unit cost 

with detailed take-off 

L: -3 to -10 

H: +3 to +15 

5.7.4.2 FY 2021 through FY 2045 Estimates 

The budget estimate for capital acquisitions in FY 2021 through FY 2025 reflects the current program of 

record. DOE/NNSA is executing 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 depicted by major capital acquisition projects and project 

proposals listed in Chapter 4, “Infrastructure and Workforce,” Figure 4–2. This planning schedule will be 

updated annually. Changes will be made based on available funding and programmatic priorities. 

The current program and the vetted project proposals included in Figure 4–2 are the basis for the cost 

estimates. Table 5–16 lists low and high estimate projections in then-year dollars for Weapons Activities 

capital acquisition projects from FY 2021 through FY 2045. As mentioned in the previous section, several 

of these projects contain a high degree of scope and cost uncertainties, resulting in a significant cost range. 

This year’s SSMP high estimate benefits from the inclusion of additional historic data in model 

development. 

Table 5–16. Weapons Activities capital acquisition estimated costs, FY 2021 – FY 2045 

Then-Year Dollars, in Billions Low a High b

Weapons Activities capital acquisition estimated costs 73.1 86.6 

a “Low” reflects the base capital acquisition estimate captured in Figure 5–19. The low value is programmatically 

informed and represents the 85th percentile for the construction projects listed in Section 4.1.2. b “High” includes additional SRT&E facilities to support stockpile stewardship and additional recapitalization costs for 

production. 

The difference in the high and low estimates as compared to the FY 2020 SSMP are a result of revised cost 

estimates, the addition of new project proposals, and changing acquisition strategies. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-38 

5.8 Affordability Analysis 

DOE/NNSA’s method for evaluating potential affordability is part of a portfolio management approach in 

line with the level of uncertainty affecting the out-years. The projected cost of continuing the program 

beyond the FYNSP incorporates some amount of uncertainty in the out-year projects based on the 

uncertainties in Stockpile Major Modernization and construction project costs. These later plans and 

estimates are compared to external straight-line budget projections that have not been adjusted to be 

more predictive. Variances are managed as the out-years estimates move into the FYNSP window, and 

greater scrutiny and prioritization are applied throughout the programming and budget processes. 

The DOE/NNSA program of record is based on requirements established through the Nuclear Weapons 

Council in coordination with DoD. DOE/NNSA must invest in making available the necessary capabilities 

and infrastructure to execute modernization programs to meet DoD timelines. In the event that 

adjustments must 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. 

Estimate of Weapons Activities Program Costs and Affordability 

Figure 5–19 depicts updated Weapons Activities budget projections beyond the FYNSP, based on the 

FY 2021 President’s Budget Request and the program of record described in Chapters 2 through 5. 

Assumptions for cost estimates are based on the current nuclear security environment. The budget 

projection incorporates the Stockpile Major Modernization program cost estimates described in 

Section 5.7.3 and the cost estimates for the planned major programmatic construction projects described 

in Section 5.7.4 and Chapter 4, Section 4.1.2. Figure 5–19 also includes out-year estimates for: 

 Reestablishing a plutonium pit production capability 

 Reestablishing a Domestic Uranium Enrichment capability 

 Revitalizing DOE/NNSA’s production centers: 

– Revitalizing Pantex assembly/disassembly capabilities 

– Expanding non-nuclear component production at KCNSC 

– Modernizing Y-12 capabilities to support strategic material production 

 Establishing and modernizing DOE/NNSA’s SRT&E capabilities for certifying nuclear weapons 

 Modernizing tritium development, production, and processing capabilities 

Figure 5–19 also includes estimates for a portfolio of replacement-in-kind projects that will sustain other 

existing mission capabilities. Programs that do not have specific cost estimates are escalated at 

2.1 percent to account for inflation and annual labor rate increases at M&O sites. 

In Figure 5–19, the projected future costs for the Weapons Activities portfolio for FY 2026–FY 2045 should 

be interpreted as the range between the red high-range total lines and the green low-range total lines for 

Weapons Activities in the figure, which represent a quantification of cost uncertainty. This total cost range 

is necessary because of uncertainties related to the individual components of the estimates, Stockpile 

Major Modernization programs, and the construction costs described earlier in this chapter. 

The dashed line represents an escalation of the final year of the FY 2021 FYNSP.37 This line represents a 

likely estimate of future years’ budget authority. The out-year Weapons Activities cost projection 

 

37 The FY 2021 Budget assumes a flat National Defense topline for FY 2026 through FY 2030, including a flat DOE/NNSA topline. 

However, for illustrative purposes of this affordability analysis and to conform to assumptions in prior versions of the SSMP, 

DOE/NNSA assumes that funding for FY 2026 through FY 2045 will be escalated at 2.1 percent. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 5-39 

illustrated in Figure 5–19 falls mostly below the escalated budget request, and DOE/NNSA considers this 

program to be affordable. In the event that adjustments need to be made, DOE/NNSA will determine 

changes to planned modernization programs and/or construction projects in coordination with DoD. 

The basis for these estimates is updated annually as DOE/NNSA develops the FYNSP request, which may 

lead to changes in the overall projection. This information illustrates the potential evolution of the 

program’s direction; it does not represent precise costs for any years other than within the FYNSP. 

Schedules and scopes can be adjusted for out-year activities as part of annual programming to address 

shortfalls, and DOE/NNSA will use updated estimates for these activities. 

It is important to note that the projection does not include potential emerging requirements. Such 

requirements may necessitate additional Stockpile Major Modernization programs, enhanced Stockpile 

Sustainment activities, or further infrastructure investments in order for DOE/NNSA to maintain a safe, 

secure, and effective nuclear deterrent in the future. Figure 5–19 also does not take into consideration 

unknown requirements, but DOE/NNSA will include any emerging requirements in future SSMPs and cost 

analyses. 

Figure 5–19. Projected out-year budget estimates for DOE/NNSA Weapons Activities 

in then-year dollars with high- and low-cost estimates, including the escalated 

President’s Budget Request

Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page 6-1 

Chapter 6 

Conclusion 

“The U.S. nuclear deterrent is the foundation of our national defense and its credibility serves

as the ultimate insurance policy against a nuclear attack.”

The Honorable Lisa E. Gordon-Hagerty, Administrator of the National Nuclear Security Administration 

U.S. Department of Energy, March 2020

This DOE/NNSA Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary

(SSMP), together with the classified Annex, is a key planning document for the nuclear security enterprise. 

The SSMP compiles the results of plans and planning efforts developed across numerous DOE/NNSA 

programs and organizations and documents the 25-year strategic plan necessary for the safety, security, 

and effectiveness of the U.S. nuclear weapons stockpile, while maintaining the scientific and engineering 

tools, capabilities, and infrastructure that underpin the enterprise. The DOE/NNSA Federal workforce 

prepares each SSMP in collaboration with its management and operating partners and coordinates the 

effort with DoD through the Nuclear Weapons Council. 

In response to evolving and new demands, and challenges related to stewardship and stockpile 

management, DOE/NNSA publishes a new version of the SSMP each year. The FY 2021 SSMP builds on 

previous SSMPs and updates the costs and resources required for execution of the program based on 

current and emerging mission needs, the strategic environment, and revised and updated guidance. 

Department of Energy/National Nuclear Security Administration | December 2020 

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Appendix A 

Requirements Mapping 

A.1 National Nuclear Security Administration Response to 

Statutory Reporting Requirements and Related Requests 

The Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary (SSMP) 

consolidates a number of statutory reporting requirements and related congressional requests. This 

appendix maps the statutory and congressional requirements to the respective chapter and section in the 

FY 2021 SSMP. 

A.2 Ongoing Requirements 

50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

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

Classified Annex 

Unclassified 

All Chapters

Classified Annex

(b) Submissions to Congress 

(1) In accordance with subsection (c), not later than March 15 of each evennumbered year, the Administrator shall submit to the congressional defense 

committees a summary of the plan developed under subsection (a). 

N/A Unclassified 

All Chapters

Classified Annex 

(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 

Classified Annex 

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 1.2 

Classified Annex 
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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, 

Sections 1.3, 1.4; 

Chapter 2, 

Sections 2.1–2.4; 

Chapter 4, 

Section 4.1;

Chapter 5, 

Sections 5.1–5.7

(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 2.1.1, 

2.1.2; Chapter 3, 

Sections 3.5–3.8 

(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 1, 

Section 1.4; 

Chapter 4, 

Sections 4.1–4.2; 

Chapter 5, 

Sections 5.1–5.7 

(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, 

Sections 2.1.1.5, 

2.2.9.2; 

Chapter 3, 

Sections 3.6.1.2, 

3.6.2.1; 

Chapter 5, 

Section 5.4.2.2 

(6) A summary of the plan regarding the research and development, 

deployment, and lifecycle sustainment of technologies described in subsection 

(d) (7). 

N/A 

(7) A summary of the assessment under subsection (d)(8) regarding the 

execution of programs with current and projected budgets and any associated 

risks. 

N/A 

(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 1, 

Section 1 text 

box; Chapter 5, 

Section 5.1.1 

(9) Such other information as the Administrator considers appropriate. N/A 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— 
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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 1.2; 

Chapter 2, 

Sections 2.1.12, 

2.5, 2.5.1–2.5.9

Classified Annex 

Chapter 2, 

Sections 2.1, 2.2; 

Tables 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, 

Sections 8.7.1–

8.7.3

Classified Annex

Chapter 2, 

Sections 2.2, 2.5; 

Tables 2-1, 2-3

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 2.1.1, 2.5, 

2.5.1–2.5.8; 

Chapter 8, 

Sections 8.2, 8.7.3

Classified Annex 

Chapter 2, 

Sections 2.2, 2.5; 

Tables 2-3, 2-4

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, 

Sections 2.2, 

2.2.1–2.2.9; 

Chapter 3, 

Sections 3.1.1, 

3.2.2

N/A 

(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, 

Sections 2.2, 

2.2.1–2.2.9; 

Chapter 3, 

Sections 3.1.1, 

3.1.2 

N/A 
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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, 

Sections 2.1, 2.1.1, 

2.2.7, 2.3.6, 2.4.1, 

2.4.3, 2.4.6; 

Chapter 3, 

Sections 3.2.1.3, 

3.2.2.3, 3.2.3.3, 

3.2.4.3, 3.3

Classified Annex 

Chapter 2, 

Sections 2.5, 

Table 2-4

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, 2.1.1, 

2.2, 2.2.1–2.2.7, 

2.3, 2.3.1–2.3.6, 

2.4, 2.4.1–2.4.8, 

2.5, 2.5.1–2.5.8; 

Chapter 3, 

Section 3.2

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 2.2, 

2.2.1–2.2.7, 2.3, 

2.3.1–2.3.6; 

Chapter 3, 

Section 3.2 

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, 

Sections 1.4, 

1.4.1–1.4.3, 1.4.5; 

Chapter 3, 

Sections 3.1.5; 

Chapter 7; 

Appendix D 

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 3, 

Section 3.1.1 

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 8.1, 8.2, 

8.3.1–8.3.3, 8.7.2, 

8.7.3 

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 8.1

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 3, 

Section 3.2; 

Chapter 8, 

Sections 8.2, 8.3.2 

N/A
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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 8.2, 8.3.2 

N/A 

(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, 

Sections 2.2.1–

2.2.7, 2.2.9; 

Chapter 3, 

Sections 3.1, 3.1.1, 

3.1.2, 3.2.1–3.2.4 

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 3, 

Sections 3.2.1–

3.2.4

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 3, 

Sections 3.2.1.3, 

3.2.2.3, 3.2.3.3, 

3.2.4.3, 3.3.1

Classified Annex 

Chapter 2, 

Section 2.5, 

Table 2-4 

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 3, 

Sections 3.1.1, 

3.2.1–3.2.4; 

Appendix D 

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 3, 

Sections 3.1.1, 

3.3.2; Appendix D

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, 

Section 7.3.4; 

Appendix B 

N/A

(i) the number of scientists, engineers, and technicians, by discipline, 

required to maintain such competencies; and 

Unclassified

Chapter 7, 

Sections 7.3.1, 

7.3.2; Appendix D

N/A
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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, 

Sections 7.4.1, 

7.4.2; Appendix D

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 4, 

Sections 4.2, 4.3

N/A 

(i) the national security strategy of the United States as set forth in the 

most recent national security strategy report of the President under 

section 3043 of this title if such strategy has been submitted as of the 

date of the plan; 

Unclassified

Chapter 4, 

Sections 4.2, 4.3

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 4, 

Sections 4.2, 4.3

N/A 

(iii) the most recent Nuclear Posture Review as of the date of the plan; Unclassified

Chapter 4, 

Sections 4.2, 4.3

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 4, 

Sections 4.21, 

4.2.2

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 8.5.1, 

8.7.4

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 8.5.5

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 3, 

Section 3.4 

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 3, 

Section 3.4

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 3, 

Section 3.4

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 3, 

Section 3.4

N/A
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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 3, 

Section 3.4

N/A 

(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 3, 

Sections 3.2.2.3, 

3.3.3

N/A 

(B) An assessment of scientific and testing instrumentation for plutonium 

at elemental and bulk conditions. 

Unclassified 

Chapter 3, 

Sections 3.2.1, 

3.2.3

N/A 

(C) An assessment of manufacturing and handling technology for 

plutonium and plutonium components. 

Unclassified 

Chapter 2, 

Section 2.4.1; 

Appendix D, 

Section D.2.2

N/A 

(D) An assessment of computational models of plutonium performance 

under static and dynamic loading, including manufactured and 

nonmanufactured conditions. 

Unclassified 

Chapter 3, 

Sections 3.2.1–

3.2.4

N/A 

(E) An identification of any capability gaps with respect to the assessments 

described in subparagraphs (A) through (D). 

Unclassified 

Chapter 3, 

Sections 3.2.1.2, 

3.2.1.3

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, 

Sections 8.2.1, 

8.2.3.5, 8.3.1, 

8.3.3, 8.8

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, 

Sections 8.2.1, 

8.2.3.5, 8.3.1, 

8.3.3, 8.8

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 2, 

Section 2.4.1

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 6

Classified Annex 

Chapter 3

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 6

Classified Annex

Chapter 3, 

Sections 3.2, 3.5; 

Tables 3-1, 3-2; 

Figure 3-2

N/A
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(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 6, 

Sections 6.1.1–

6.1.3, 6.2.3, 6.2.4

Classified Annex

Chapter 3, 

Sections 3.3, 3.7

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 8.6.2, 

8.6.3

Classified Annex 

Chapter 3, 

Sections 3.4.2, 3.8; 

Tables 3-5, 3-6

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 8.7–8.9

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 

(e) Nuclear Weapons Council assessment 

(1) For each detailed report on the plan submitted under subsection (b)(2), the 

Nuclear Weapons Council shall conduct an assessment that includes the 

following: 

(A) An analysis of the plan, including— 

(i) whether the plan supports the requirements of the national security 

strategy of the United States or the most recent quadrennial defense 

review, as applicable under subsection (d)(4)(A), and the Nuclear 

Posture Review; 

(ii) whether the modernization and refurbishment measures described 

under subparagraph (A) of subsection (d)(4) and the schedule 

described under subparagraph (B) of such subsection are adequate to 

support such requirements; and 

(iii) whether the plan supports the stockpile responsiveness program 

under section 2538b of this title in a manner that meets the objectives 

of such program and an identification of any improvements that may 

be made to the plan to better carry out such program. 

(B) An analysis of whether the plan adequately addresses the requirements 

for infrastructure recapitalization of the facilities of the nuclear security 

enterprise. 

(C) If the Nuclear Weapons Council determines that the plan does not 

adequately support modernization and refurbishment requirements under 

subparagraph (A) or the nuclear security enterprise facilities infrastructure 

recapitalization requirements under subparagraph (B), a risk assessment 

with respect to— 

(i) supporting the annual certification of the nuclear weapons stockpile; 

and 

(ii) maintaining the long-term safety, security, and reliability of the 

nuclear weapons stockpile. 

(2) Not later than 180 days after the date on which the Administrator submits 

the plan under subsection (b)(2), the Nuclear Weapons Council shall submit to 

the congressional defense committees a report detailing the assessment 

required under paragraph (1). 

N/A N/A 
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50 U.S. Code § 2523 

FY 2020 

Response 

FY 2021 

Response 

(f) Definitions – In this section: 

(1) The term “budget”, with respect to a fiscal year, means the budget for 

that fiscal year that is submitted to Congress by the President under section 

1105(a) of title 31. 

(2) The term “future-years nuclear security program” means the program 

required by section 2453 of this title. 

(3) The term “nuclear security budget materials”, with respect to a fiscal year, 

means the materials submitted to Congress by the Administrator in support 

of the budget for that fiscal year. 

(4) The term “quadrennial defense review” means the review of the defense 

programs and policies of the United States that is carried out every four years 

under section 118 of title 10. 

(5) The term “weapons activities” means each activity within the budget 

category of weapons activities in the budget of the Administration. 

(6) The term “weapons-related activities” means each activity under the 

Department of Energy that involves nuclear weapons, nuclear weapons 

technology, or fissile or radioactive materials, including activities related to—

(A) nuclear nonproliferation; 

(B) nuclear forensics; 

(C) nuclear intelligence; 

(D) nuclear safety; and 

(E) nuclear incident response. 
Department of Energy/National Nuclear Security Administration | December 2020

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50 U.S. Code § 2538a 

FY 2020 

Response 

FY 2021 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 a pilot period of not less than 90 days during 2027 (subject to 

subsection [b]), demonstrates the capability to produce war 

reserve plutonium pits at a rate sufficient to produce 80 pits per year. 

Chapter 1, 

Section 1.4.5; 

Chapter 2, 

Section 2.4.1; 

Chapter 8, 

Section 8.2.4; 

Appendix D, 

Section D.2.2

Message from the 

Administrator; 

Chapter 3, Sections 

3.3.1.1; 3.7.9.2; 

Chapter 4, Section 

4.1.2; Chapter 5, 

Sections 5.3.2.1, 

5.3.3, 5.4.2.1–

5.4.2.2, 5.6.3.1, 

5.7.3.9

(b) Authorization of two-year delay of demonstration requirement 

The Secretary of Energy and the Secretary of Defense may jointly delay, for not 

more than two years, the requirement under subsection (a)(5) if- 

(1) the Secretary of Defense and the Secretary of Energy jointly submit to 

the congressional defense committees a report describing- 

(A) the justification for the proposed delay; 

(B) the effects of the proposed delay on stockpile stewardship and 

modernization, life extension programs, future stockpile strategy, and 

dismantlement efforts; and 

(C) whether the proposed delay is consistent with national policy 

regarding creation of a responsive nuclear infrastructure; and 

(2) the Commander of the United States Strategic Command submits to the 

congressional defense committees a report containing the assessment of 

the Commander with respect to the potential risks to national security of 

the proposed delay in meeting- 

(A) the nuclear deterrence requirements of the United States Strategic 

Command; and 

(B) national requirements related to creation of a responsive nuclear 

infrastructure. 

N/A

(c) Annual certification 

Not later than March 1, 2015, and each year thereafter through 2027 (or, if the 

authority under subsection (b) is exercised, 2029), 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 2, 

Section 2.4.1; 

Chapter 8, 

Section 8.2.4;

Unclassified, 

Chapter 3, 

Sections 3.3.1.1.1.1, 

3.3.1.1.1.3

(d) Plan 

If the Secretary of Energy does not make a certification under subsection (c) 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 
Department of Energy/National Nuclear Security Administration | December 2020

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page A-11

A.3 Other Requirements 

H.R.244 – Consolidated Appropriations Act, 2017, P.L. 115-31 

FY 2020 

Response

FY 2021 

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 

Chapter 2, 

Sections 2.2, 

2.2.1–2.2.6, 2.3 

Classified Annex

 
Department of Energy/National Nuclear Security Administration | December 2020

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page A-12

A.4 Related Legislation 

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 

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. 
Department of Energy/National Nuclear Security Administration | December 2020

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page A-13

50 U.S. Code § 2521 

(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. 

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. 

50 U.S. Code § 2524 

§ 2524. Stockpile management program 

(a) Program required 

The Secretary of Energy, acting through the Administrator for Nuclear Security and in consultation with the Secretary of 

Defense, shall carry out a program, in support of the stockpile stewardship program, to provide for the effective 

management of the weapons in the nuclear weapons stockpile, including the extension of the effective life of such 

weapons. The program shall have the following objectives: 

(1) To increase the reliability, safety, and security of the nuclear weapons stockpile of the United States. 

(2) To further reduce the likelihood of the resumption of underground nuclear weapons testing. 

(3) To achieve reductions in the future size of the nuclear weapons stockpile. 

(4) To reduce the risk of an accidental detonation of an element of the stockpile. 

(5) To reduce the risk of an element of the stockpile being used by a person or entity hostile to the United States, its 

vital interests, or its allies. 

(b) Program limitations 

In carrying out the stockpile management program under subsection (a), the Secretary of Energy shall ensure that— 

(1) any changes made to the stockpile shall be made to achieve the objectives identified in subsection (a); and 

(2) any such changes made to the stockpile shall— 

(A) remain consistent with basic design parameters by including, to the maximum extent feasible, components 

that are well understood or are certifiable without the need to resume underground nuclear weapons testing; 

and 

(B) use the design, certification, and production expertise resident in the nuclear security enterprise to fulfill 

current mission requirements of the existing stockpile. 

(c) Program budget 

In accordance with the requirements under section 2529 of this title, for each budget submitted by the President to 

Congress under section 1105 of title 31, the amounts requested for the program under this section shall be clearly 

identified in the budget justification materials submitted to Congress in support of that budget. 

 
Department of Energy/National Nuclear Security Administration | December 2020

 Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page A-14

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. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page B-1 

Appendix B 

Exascale Computing Initiative 

The 2017 National Security Strategy mandates that “to maintain our competitive advantage, the 

United States will prioritize emerging technologies critical to economic growth and security, such as data 

science, encryption, gene editing, new materials, nanotechnology, advanced computing technologies, and 

artificial intelligence.” In addition, the 2018 Nuclear Posture Review states that the Department of 

Energy’s National Nuclear Security Administration (DOE/NNSA) will “maintain and enhance the 

computational, experimental, and testing capabilities needed to annually assess nuclear weapons.” To 

maintain competitive advantage and the necessary capabilities for the annual assessment, the 

United States must retain state-of-the-art capabilities in high performance computing (HPC). HPC will also 

help ensure national security, economic prosperity, technological strength, and scientific and energy 

research leadership. Failure to address national security, science, and growing big data needs will open 

the door to other nations with a demonstrated commitment to HPC investment to take the lead in a 

number of areas. Risk would increase not only in high-end computing, but also could eventually in science, 

national defense, energy innovation, and the commercial computing market. 

The National Strategic Computing Initiative (NSCI) 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 NSCI include the National Science 

Foundation, the intelligence community, and the Departments of Commerce, Defense, Justice, and 

Homeland Security. Major focus areas of the NSCI are the exploration and development of quantum 

computing, bio computing, and exascale computing. Within that initiative, DOE, represented by a 

partnership between the DOE Office of Science and NNSA, has the lead responsibility for focusing and 

implementing the joint Exascale Computing Initiative. This initiative focuses on advanced simulation that 

continues exploiting MOSFET1

 technology 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 exaFLOPS2

 in the early to mid-2020s. 

B.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), NNSA will need to focus on six challenges: 

 Developing HPC technologies and systems, in close partnership with computer vendors, that will 

provide at least an eight-fold increase in sustained application code performance over the 

currently largest NNSA supercomputer (a 125-petaFLOPS system) 

 

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. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page B-2 

 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 we have experienced in the past 2 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 computing facilities to ready them for site future petascale and exascale platforms 

through increasing structural integrity, power, and cooling capabilities 

B.2 Approaches and Strategies 

To achieve DOE/NNSA’s exascale goals, the U.S. Government has been interacting with industry in HPC 

technology development. Past partnerships between the U.S. Government and industry have led to 

development of innovative technologies that met both Federal and private sector objectives. 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 exascaleclass system to DOE’s Office of Science in FY 2021 – 2022 and another to NNSA in FY 2023. This joint 

procurement supports the program offices when they share critical non-recurring engineering 

development costs with the selected vendor team. 

The current spend plan for Exascale Computing Initiative elements is delineated in Table B–1. In FY 2021, 

the NNSA portion of the Exascale Computing Initiative is categorized as ASC’s Advanced Technology 

Development and Mitigation (ATDM) subprogram, which is a part of the Defense Applications and 

Modeling portfolio (composed of Integrated Codes, Physics and Engineering Models, and Verification and 

Validation subprograms) that funds the application of the next-generation exascale technologies for the 

weapons mission, as well as a portion of the Computational Systems and Software Environment (CSSE) 

subprogram that procures the El Capitan system. In addition, the NNSA Exascale Computing Initiative 

portfolio includes the Exascale Computing Facility Modernization (ECFM) project to prepare for siting the 

NNSA El Capitan exascale system in FY 2023. Future exascale investments will include improvements to 

remote computing infrastructure to advance complex-wide HPC capabilities. 

Table B–1. NNSA Exascale Computing Initiative funding schedule for FY 2021 through 2025 

Exascale Computing Initiative Elements 

(dollars in millions) 

FY 2021 

Request 

FY 2022 

Request 

FY 2023 

Request 

FY 2024 

Request 

FY 2025 

Request 

Advanced Technology Development and Mitigation 40 40 17 5 – 

Defense Applications and Modeling 28 28 33 40 – 

Computational Systems and Software Environment 24 20 30 36 – 

Exascale Computing Facility Modernization 29.2 – – – – 

Procurement 114 181 167 146 68 

Total, NNSA Exascale Initiative 235.2 269 247 227 68 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page B-3 

Advanced Technology Development and Mitigation 

A major portion of the ASC ATDM subprogram is designated as part of the DOE Exascale Computing Project 

(ECP), a jointly managed collaboration between NNSA and DOE Office of Science via DOE Order 413.3B 

(tailored). This portion consists of the following two focus areas. 

 ATDM/ECP Application Development: NNSA is responsible for determining the scope and 

management of the stockpile simulation application development that is included in this focus 

area. Confidence in the safety and reliability of the nuclear weapons stockpile relies on highfidelity simulations of all of the physical processes occurring within a nuclear weapon and the 

processes that support the design, production, maintenance, and evaluation of the nuclear 

arsenal, including life extension programs and weapons dismantlement. The ASC IDCs model 

various aspects of nuclear weapons, and each has on the order of several million lines of code to 

accurately reflect the multi-scale, multi-physics phenomena occurring in a nuclear weapon. The 

accuracy of these IDCs underpins confidence in the U.S. nuclear deterrent and must be improved 

through ATDM Application funding to ensure continued future confidence in the Nation’s 

stockpile. Exploiting the multi-level parallelism demanded by emerging architectures leading to 

exascale requires significant investment in new stockpile simulation code development over the 

next 5–7 years. 

 ATDM/ECP Software Technology: With its stockpile stewardship mission, ASC will make strategic 

investments in ECP software technology to directly support its IDC development requirements, 

where appropriate. Funding will support further development of compilers, math libraries, and 

programming models for the 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 control of precision 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. The remainder of the ATDM 

portfolio includes funding that supports a project at the national security laboratories to work on 

the DOE-National Cancer Institute Collaboration that seeks to increase the capacity and capability 

of an enduring national HPC ecosystem. 

Construction: Exascale Computing Facility Modernization at Lawrence Livermore National Laboratory 

In addition to hardware and software technology development efforts, the exascale systems must meet 

exacting power usage, reliability, and functionality criteria. Each exascale-class platform will require a 

peak of between 28 and 45 megawatts to operate, as well as requisite cooling. Managing a service load 

of this magnitude, which is over and above existing capabilities in ASC facilities, is necessitating major 

facility modernizations. The ECFM project is intended to fill this gap by adding 40 megawatts of power 

(bringing the total to 85 megawatts) and 18,000 tons of water cooling (bringing the total to 28,000 tons) 

by calendar year 2022. A detailed engineering assessment in preparation for Critical Decision (CD)-2/3 

(Approve Performance Baseline/Approve Start of Construction) proved that the building already met 

requirements to support 315 pounds per square foot of rack load and adequate square footage, so no 

additional structural or architectural investments are necessary in this area. The ECFM is essential for 

Lawrence Livermore National Laboratory (LLNL) to successfully site the NNSA exascale system at the 

beginning of FY 2023. Soon after receiving CD-2/3 in FY 2020 the ECFM project team awarded 

construction contracts and moved into the construction phase of the project. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page B-4 

Computational Systems and Software Environment – Exascale System (El Capitan) 

NNSA is embarking on a multi-year collaboration with the selected 2023 exascale system vendor and its 

subcontractors to work on non-recurring engineering and system integration issues for 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. 

Computational Systems and Software Environment – Next-Generation Computing Technologies

In FY 2021, NNSA will transition its previously ATDM-funded computing technology activities to CSSE. 

NNSA will continue evaluating its next-generation IDCs’ performance portability on advanced architecture 

prototype systems. Funding will be for development, maintenance, and user support for the NNSA trilaboratory software stack that will be required for the next-generation codes to run efficiently on these 

advanced technology systems. In addition, 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. 

Defense Application and Modeling – Next-Generation Application Development 

In FY 2021, NNSA will begin 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. 

B.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 B–1. The Integrated Project Team provides planning, execution, coordination, and communication 

for the ECP to ensure that the project’s objectives are achieved on schedule and within budget and are 

consistent with quality, environment, safety, and health standards. 

Figure B–1. Exascale Computing Project integrated project team 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page B-5 

B.4 Milestones 

DOE/NNSA has five milestones for FY 2021: 

 Continue engagement with the El Capitan system vendor on non-recurring engineering activities 

 Map ASC applications to target exascale architecture with machine-specific performance analysis 

 Install El Capitan’s early access hardware at LLNL 

 Begin transition of selected NNSA ATDM application and software technologies to the ASC 

Defense Applications and Modeling portfolio for annual assessment mission 

 Begin transition of selected NNSA ATDM computing technologies to its CSSE portfolio 

B.5 Conclusion 

DOE/NNSA, through the ASC Exascale effort, is investing in products and approaches that are directly 

related to anticipated disruptive changes in the HPC ecosystem. Activities include R&D partnerships with 

multiple HPC vendors, development of 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. Cooperation with computer vendors has also led to significant advances in HPC 

software and hardware technologies. These activities have provided experience and lessons learned and 

have already delivered a variety of software development tools and libraries that many ASC applications 

now rely on. To complete this effort, more intensive research, development, and engineering effort is 

needed for DOE/NNSA to achieve the goal of deploying an exascale capability in 2023. 

Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page C-1 

Appendix C 

Capabilities and Definitions 

This appendix describes the breadth of capabilities maintained by Weapons Activities programs in the 

Department of Energy/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. The capabilities 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 portfolios, each containing a suite of capabilities that 

together address a particular aspect of Weapons Activities. In part, this appendix supports legislative 

requirements listed in Appendix A. 

Capability Definition Portfolio 

Accelerator and 

Pulsed Power Science, 

Technology, and 

Engineering a

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. Pulsed 

power devices accumulate energy over long periods of time and 

release it rapidly to generate pressures, temperatures, and 

radiation conditions similar to those produced in or by nuclear 

weapons. Experiments and testing with these devices produces 

data critical to understanding physical phenomena, qualifying 

nuclear weapon components and improving performance 

assessments. 

Weapon Science 

and Engineering

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 postfabrication 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. 

Weapon Science 

and Engineering
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page C-2 

Capability Definition Portfolio 

Advanced 

Manufacturing

Advanced manufacturing uses innovative techniques from industry, 

academia, or internal research and development 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. 

Weapon 

Component 

Production

Atomic and Plasma 

Physics

Atomic physics is the study of atomic systems, such as a collection 

of atoms and electrons, and their interaction with X-rays. 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 and 

X-rays. 

Weapon Science 

and Engineering

Chemistry and 

Chemical 

Engineering a

Chemistry studies the elemental composition, structure, bonding, 

and properties of matter. Chemical engineering is essential for 

purifying, synthesizing, processing, and fabricating materials at 

large scale. 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. 

Weapon Science 

and Engineering

Energetic and 

Hazardous Material 

Handling, Packaging, 

Processing, and 

Manufacturing (High 

Explosives and 

Lithium) 

Energetic and hazardous materials have the potential to harm 

humans, animals, or the environment. As a result they require safe 

and secure handling, packaging, processing, manufacturing, and 

inspection. These materials include lithium, beryllium, mercury, 

explosives, propellants and detonators.

Weapon Material 

Processing and 

Manufacturing

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. 

Weapon Design and 

Integration

High Energy Density 

Physics

High energy density physics is the study of matter and radiation 

under extreme conditions such as those in a functioning nuclear 

weapon and reproduced in high-temperature experiments. 

Facilities such as the National Ignition Facility, Omega Laser Facility, 

and the Z pulsed power facility generate high energy density states 

producing data exploring the physical processes that occur in 

plasma states to validate computational models. 

Weapon Science 

and Engineering

High Explosives and 

Energetics Science 

and Engineering a

High explosives and energetics science and engineering is 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. Understanding of these materials is necessary for 

understanding nuclear weapon performance. 

Weapon Science 

and Engineering
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Capability Definition Portfolio 

High Performance 

Computing

High performance computing 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 in 

computer, information, and mathematical sciences to support 

developing and operating high-performance computing. 

Weapon Simulation 

and Computing 

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 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 multi-physics 

design codes and predicting nuclear weapon performance. 

Weapon Science 

and Engineering 

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. 

Transportation and 

Security

Laser and Optical 

Science, Technology, 

and Engineering a

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. Advancements in these areas is 

important to qualifying new components and systems and 

improving performance assessments. 

Weapon Science 

and Engineering

Materials Science and 

Engineering

Materials science, in the context of stockpile stewardship, is the 

study of how materials in a nuclear weapon behave under 

moderate to extreme conditions of temperature and pressure. 

Materials engineering involves the evaluation and selection of 

materials for these environments. Strength, aging, compatibility, 

viability, and damage mechanics are among the materials 

characteristics to be evaluated. Materials science and engineering 

play a key role in resolving stockpile and production issues, 

validating computational models, and developing new materials 

(e.g., materials produced through additive manufacturing). 

Weapon Science 

and Engineering

Metal and Organic 

Material Fabrication, 

Processing, and 

Manufacturing

Specialized components and materials that are not commercially 

available must be produced within the nuclear security enterprise. 

This production requires synthesis of organic materials and 

processing, manufacturing, and inspection of metallic and organic 

products, based on knowledge of material behavior, compatibility, 

and aging. This would include, but is not limited to, polymer 

material and part manufacturing. 

Weapon Material 

Processing and 

Manufacturing
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Capability Definition Portfolio 

Non-Nuclear 

Component 

Production a

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 

Production

Nuclear Physics and 

Engineering a

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. 

Weapon Science 

and Engineering

Physical Security Physical security protects the Nation’s nuclear materials, 

infrastructure assets, and the 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. 

Transportation and 

Security

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. 

Weapon Design and 

Integration

Radiochemistry a 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, Omega Laser Facility, and the Z pulsed 

power facility can use radiochemical tracers in their diagnostic 

suites. 

Weapon Science 

and Engineering

Secure Transportation Protection and movement of nuclear weapons, weapon 

components, and special nuclear material between facilities 

includes design and fabrication or modification of vehicles, design 

and fabrication of special communication systems, and training of 

Federal agents. 

Transportation and 

Security

Simulation Codes and 

Models

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. 

Weapon Simulation 

and Computing

Special Nuclear 

Materials Handling, 

Packaging, and 

Processing (Plutonium 

and Uranium) 

Components that contain special nuclear materials (e.g., plutonium, 

enriched uranium) require special conduct of operations, physical 

security protection, facilities, and equipment to handle, package, 

process manufacture, and inspect these components.

Weapon Material 

Processing and 

Manufacturing
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Capability Definition Portfolio 

Weapon Simulation 

and Computing a

Weapon Simulation and Computing 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 in computer, information, and mathematical sciences 

to support developing and operating high-performance computing. 

Weapon Simulation 

and Computing

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 Assembly, 

Storage, Testing, 

and Disposition

Tritium Production, 

Handling, and 

Processing

Tritium has a 12-year half-life and must be periodically replenished 

in gas transfer systems. Production, handling, and processing of 

tritium includes the recovery, extraction, refinement, storage, 

filling, and inspection of gas transfer systems. 

Weapon Material 

Processing and 

Manufacturing

Weapon Assembly, 

Storage, and 

Disposition a

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 sub-systems requires special safety and 

security processes and protocols. 

Weapon Assembly, 

Storage, Testing, 

and Disposition

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 special nuclear materials and other exotic 

materials. Component process development is needed whenever 

process changes are made to reduce cost or production time. 

Weapon 

Component 

Production

Weapon Component 

and System 

Prototyping

The 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 Department of Defense delivery systems in 

realistic environments. 

Weapon 

Component 

Production

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. 

Weapon Assembly, 

Storage, Testing, 

and Disposition
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Capability Definition Portfolio 

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 nonnuclear components and the nuclear explosives package, and 

between the DOE/NNSA and Department of Defense systems. 

Weapon Design and 

Integration

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. 

Weapon Design and 

Integration

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. 

Weapon Design and 

Integration

a Title changed since FY 2020 Stockpile Stewardship and Management Plan. 
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Appendix D 

Glossary 

3D printing—Also known as additive manufacturing, which turns digital three-dimensional models into 

solid objects by building them up in layers.

abnormal environment—An environment, as defined in a weapon’s stockpile-to-target sequence and 

military characteristics, in which the weapon is not expected to retain full operational reliability, or an 

environment that is not expected to occur during nuclear explosive operations and associated activities. 

additive manufacturing—A manufacturing technique that builds objects layer by layer, according to 

precise design specifications, compared to a traditional manufacturing technique in which objects are 

carved out of a larger block of material or cast in molds and dies. 

advanced manufacturing—Modern technologies necessary to enhance secure manufacturing capabilities 

and provide timely support for critical needs of the stockpile.

Alteration—A material change to, or a prescribed inspection of, a nuclear weapon or major assembly that 

does not alter its operational capability, yet is sufficiently important to the user regarding assembly, 

maintenance, storage, or test operations to require controlled application and identification. 

annual assessment process—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 system—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 do ensure the 

weapon will operate correctly when a unique signal to do so is properly activated. 

B61—An air-delivered gravity bomb. 

B61-12 Life Extension Program (LEP)—An LEP to consolidate four families of the B61 bomb into one and 

improve the safety and security of the oldest weapon system in the U.S. arsenal. 

B83-1—An air-delivered gravity bomb. 

Boost—The process that increases the yield of a nuclear weapon’s primary stage through fusion reactions.

canned subassembly (CSA)—A component of a nuclear weapon that is hermetically sealed in a metal 

container. A CSA and the primary make up a weapon’s nuclear explosive package. 
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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.

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. 

conventional high explosive (CHE)—A high explosive that detonates when given sufficient stimulus via a 

high-pressure shock. Stimuli from severe accident environments involving impact, fire, or electrical 

discharge may also initiate a CHE. 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. 

data loss prevention (DLP)—DLP is a strategy for making sure that end users do not send sensitive or 

critical information outside the corporate network. DLP also includes software products that aid network 

administrators in controlling what data end users can transfer. 

defense-in-depth—The security approach whereby layers of cybersecurity and information assurance 

solutions are used to establish an adequate security posture. Implementation of this strategy also is 

recognized due to the highly interactive nature of the various systems and networks. Cybersecurity 

defense-in-depth must be considered within the context of the shared risk environment, given that any 

single system cannot be adequately secured unless all interconnected systems are adequately secured. 

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.

deuterium—An isotope of hydrogen whose nucleus contains one neutron and one proton. 

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) through analysis of the ability to meet military requirements and 

assessment of schedule, cost, material, and production impacts. 
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encryption—Technical controls to protect information as it passes throughout a network and resides on 

computers. These methods protect sensitive information during storage and transmission and provide 

functionality to reduce the risk of both intentional and accidental data compromise and alteration. 

enterprise forensics—The performance of real-time, remote inspections at the binary level of all data on 

a given system. The inspections include operating memory, physical storage devices, and virtualization 

mechanisms on any machine at a given time. 

Enterprise Governance, Risk, and Compliance—The official corporate and enterprise program repository 

used to conduct continuous performance monitoring and reporting of information security program 

management, operations, and technical controls (e.g., authority-to-operate packages, deviations, incident 

management reporting). 

Enterprise Information System—Systems within NNSA for which the authorization boundary covers 

multiple sites and multiple local Authorization Official jurisdictions. 

exascale computing—Computing systems capable of at least 1 exaFLOPS, or a 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).” 

firewalls—Systems that can be implemented in hardware and/or software that are designed to prevent 

unauthorized access to or from private networks connected to the Internet. 

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—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. 

general purpose infrastructure—The buildings, equipment, utilities, roads, etc., that support operation of 

the nuclear security enterprise, but are not specifically program-focused. 
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high explosives—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—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. 

Information Assurance Response Center—The NNSA facility that continuously monitors all activity going 

through the nuclear security enterprise computer firewall system, to provide intrusion detection and 

event forensics. 

information system—A combination of information, computer, and telecommunications resources and 

other information technology and personnel resources that collect, record, process, store, communicate, 

retrieve, and display information. 

information technology—The equipment or interconnected system or subsystem of equipment used in 

the automatic acquisition, storage, manipulation, management, movement, control, display, switching, 

interchange, transmission, or reception of data or information. Information technology includes 

computers, ancillary equipment, software, firmware, and related procedures, services, and resources. 

Information Technology Infrastructure—The shared technology resources that provide the platform for 

the specific information system applications at a site or NNSA/DOE-wide. It consists of a set of physical 

devices and software applications that are required to operate the entire nuclear security enterprise. 

insensitive high explosive—A high explosive substance that is so insensitive that the probability of 

accidental initiation or transition from burning to detonation is negligible. 

integrated design code (IDC)—A simulation code containing multiple physics and engineering models that 

have been validated experimentally and computationally. An IDC is used to simulate, understand, and 

predict the behavior of nuclear and non-nuclear components and nuclear weapons under normal, 

abnormal, and hostile conditions. 

intrusion prevention—A network security device that monitors network activities for malicious activities 

such as security threats or policy violations. The main function of an intrusion prevention system is to 

identify suspicious activity, log the information, and report it. 

Joint Cybersecurity Coordination Center (JC3)—The cybersecurity incident response coordination, 

reporting, and tracking element for the entire DOE enterprise. JC3 provides computer security support to 

collect, analyze, and share cybersecurity information for all of DOE, including DOE’s Energy Information 

Administration and Power Marketing Administration, as well as NNSA’s national security laboratories, 

nuclear weapons production facilities, and Nevada National Security Site. JC3 is managed and operated 

by the DOE Chief Information Officer. 

joint test assembly—(1) An electronic unit that contains sensors and instrumentation that monitor the 

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. 
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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 in order 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 other extreme high-voltage, high-temperature environments.

limited life component—A weapon component or subsystem whose performance degrades with age and 

must be replaced. 

manufacturing readiness level (MRL)—A means of communicating the degree to which a component or 

subsystem is ready to be produced. MRLs represent many attributes of a manufacturing system 

(e.g., people, manufacturing capability, facilities, conduct of operations, and tooling). There are nine 

MRLs, with the lowest beginning at product development and ending with the highest, which is steadystate production. 

mark quality—Weapon or weapon-related material that is certified by DOE/NNSA or its prime contractor 

quality organization to meet all applicable design requirements, drawings, and known design intent. 

Sometimes called “Diamond Stamp.”

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. 

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. 

multilayered malware protection—Commercial software that guards against multiple threat vectors such 

as viruses, spyware, and Trojans. The software searches a hard disk or other media for known threat 

vectors and removes any that are found. 

national security laboratory—Los Alamos National Laboratory, Sandia National Laboratories, or Lawrence 

Livermore National Laboratory. 

national security system—Any telecommunications or information system operated by the 

U.S. Government whose function, operation, or use involves intelligence activities, cryptologic activities 

related to national security, command and control of military forces, or equipment that is an integral part 

of a weapon or weapons system or is critical to the direct fulfillment of military or intelligence missions. 

The term excludes any system used for routine administrative and business applications (including payroll, 

finance, logistics, and personnel management applications). 

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. 
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network intrusion detection (NID)—An intrusion detection system inspects all inbound and outbound 

network activity and identifies suspicious patterns that may indicate an attempt to break into or 

compromise a system. NID systems (1) monitor all network traffic by inspecting and screening all inbound 

and outbound information technology network activity for patterns that may indicate an attempt to break 

in or compromise a system and (2) provide alerts based on predefined rules. These rules or signatures 

are updated as needed to reflect information learned from exploitation or attack attempts. When 

triggered, an NID system begins capturing network traffic related to the event in question, and the data 

are made available to security analysts. Notification is also sent to the Security Information and Event 

Management tool. 

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. 

NNSA Information Technology System—An information system that is owned and/or operated by NNSA 

or by contractors on behalf of NNSA to accomplish a Federal function. Regardless of whether NNSA 

Federal employees have access, this does not include information systems operated by management and 

operating contractors unless such systems’ primary purposes are to accomplish Federal functions. 

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. 

non-War Reserve—Weapon material that is not designated for the War Reserve stockpile, but is to be 

used by DOE/NNSA or delivered to DoD for the purpose of training, testing, and evaluating War Reserve 

material. 

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. 

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.

nuclear weapons production site—The Kansas City National Security Campus, Pantex Plant, Y-12 National 

Security Complex, or Savannah River Site. Los Alamos National Laboratory and Sandia National 

Laboratories also perform some specific weapons production activities. 

Other Program Money—Funding that is found outside of an 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. 
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out-years—The years that follow the 5-year period of the FYNSP. 

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 basically correspond 

to Phases 1 through 6 of the nuclear weapons life cycle.

physical security—The application of 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. 

primary—The first stage of a two-stage nuclear weapon. 

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. 

Protected Distribution Systems—Wireline or fiber optic distribution systems used to transmit and protect 

unencrypted classified signal and data lines that exit secure areas and traverse through areas of lesser 

classification or security control. 

qualification—The process of ensuring that design, product, and all associated processes are capable of 

meeting customer requirements. Authorizes the listed items for an intended use (i.e., War Reserve, 

Training, Evaluation, etc.). Generally includes Laboratory (Design Agency) 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. 

quantification of margins and uncertainties—The methodology used in the post-nuclear-testing era to 

facilitate analysis and communicate confidence in assessing and certifying that stockpile weapons will 

perform safely, securely, and reliably. Scientific judgment of experts at the national security laboratories 

plays a crucial role in this determination, which is based on metrics that use experimental data, physical 

models, and numerical simulations. 

quantum computing—The area of study focused on developing computer technology based on the 

principles of quantum-mechanical theory, which explains the nature and behavior of energy and matter 

on the atomic and subatomic level. 

radiation case—A vessel that confines the radiation generated in a staged nuclear weapon. 

reservoir—A vessel containing deuterium and tritium that permits its transfer as a gas in a nuclear 

weapon.

Retrofit Evaluation System Test—A test program conducted during retrofit of an NNSA weapon system on 

randomly selected, newly retrofitted weapons to determine the effect of the retrofit on the weapon 

system’s reliability and to verify that the purpose of the retrofit is fully achieved. The program may consist 

of flight testing and/or laboratory testing.

Safeguards Transporter—A highly specialized trailer designed to safeguard nuclear weapons and special 

nuclear materials while in transit. 
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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 area—A defined area containing safeguards and security interests that requires physical 

protection measures. The types of security areas used by DOE/NNSA include property protection areas, 

limited areas, exclusion areas, protected areas, material access areas, and functionally specialized security 

areas such as sensitive compartmented information facilities, classified computer facilities, and secure 

communications centers. 

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). The terms “stockpile life,” 

“deployed life,” and “useful life” are subsumed by service life. 

significant finding investigation—A formal investigation by a committee, chaired by an employee of a 

national security laboratory, to determine the cause and impact of a reported anomaly and to recommend 

corrective actions as appropriate. 

special nuclear material (SNM)—Plutonium, uranium-233, or uranium enriched in the isotopes 

uranium-233 or uranium-235. The Nuclear Regulatory Commission defines three categories of quantities 

of SNM according to the risk and potential for its use in the creation of a fissile explosive. Category I is 

the category of the greatest quantity and associated risk; Category II is moderate; Category III is the 

lowest. 

Stewardship Capability Delivery Schedule (SCDS)—A planning framework for delivery of high-level science, 

technology, and engineering capabilities for mission application. The SCDS identifies the complex set of 

interlinked computational, experimental, and technology maturation activities needed for stockpile 

annual assessment, resolution of significant finding investigations, qualification and certification of life 

extension programs, and identification of options for the future deterrent. 

stockpile-to-target sequence—A document that defines the logistical and employment concepts and 

related physical environments involved in delivering a nuclear weapon from storage and assembly, testing 

it, transporting it, and delivering the 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. 

supply chain risk management (SCRM)—The coordinated efforts of an organization to help identify, 

monitor, detect, and mitigate threats to supply chain continuity. Threats to the supply chain include cost 

volatility, material shortages, supplier financial issues and failures, and natural and manmade disasters. 

SCRM strategies and software help an organization foresee potential issues and adapt to both those risks 

and unforeseeable supply chain disruptions as quickly and efficiently as possible. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page D-9 

surety—The assurance that a nuclear weapon will operate safely, securely, and reliably if deliberately 

activated and that no accidents, incidents, or unauthorized detonations will occur. Factors contributing 

to that assurance include model validation for weapon performance based on experiments and 

simulations, material (e.g., military equipment and supplies), personnel, and execution of procedures. 

surveillance—Activities that provide data for evaluation of the stockpile, giving confidence in the Nation’s 

deterrent by demonstrating mission readiness and assessment of safety, security, and reliability 

standards. These activities may include laboratory and flight testing of systems, subsystems, and 

components (including those of weapons in the existing stockpile, newly produced weapons, or weapons 

being disassembled); inspection for unexpected wear or signs of material aging; and destructive or 

nondestructive testing. 

sustainment—A program to modify and maintain a set of nuclear weapon systems.

technology maturation—Advancing laboratory-developed technology to the point where it can be 

adopted and used by U.S. industry. 

technology readiness level (TRL)—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). 

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. 

threat information—Any information related to a threat that might help an organization protect itself 

against a threat or detect the activities of an actor. Major types of threat information include indicators; 

tactics, techniques, and procedures; security alerts; threat intelligence reports; and tool configurations. 

tractor—A modified and armored vehicle to transport the Safeguards Transporter trailer. 

tritium—A radioactive isotope of hydrogen whose nucleus contains two neutrons and one proton and is 

produced in nuclear reactors by the action of neutrons on lithium nuclei. 

virtual desktop infrastructure—Software technology that separates the desktop environment and 

associated application software from the physical client device used to access it. 

vulnerability scanning—The application of software that seeks out security flaws based on a database of 

known flaws, testing systems for the occurrence of these flaws, and generation of a report of the findings 

that can be used to tighten a networks security. 

W76-1 LEP—An LEP 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—An LEP 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. 
Department of Energy/National Nuclear Security Administration | December 2020 

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page D-10 

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 munitions 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. 

wireless security—Security solution designed to test and evaluate the impact of mobile and fixed wireless 

communication devices used in or near classified and sensitive unclassified activity areas for the purpose 

of determining risks and countermeasures. 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page E-1 

Appendix E 

Lists of Figures and Tables 

List of Figures 

Figure 1–1. Timeline for key infrastructure and capability investments for future warheads ............................... 1-6

Figure 1–2. Historical average age growth of NNSA major programmatic facilities and a projection 

of the planned stabilization of average age after executing the FY 2021 President’s Budget 

Request-Informed Line-Item Plan ........................................................................................................ 1-7 

Figure 2–1. DOE/NNSA warhead activities ............................................................................................................. 2-6 

Figure 3–1. Weapons Activities capability elements .............................................................................................. 3-2 

Figure 3–2. DOE/NNSA Weapons Activities capability portfolios ........................................................................... 3-3 

Figure 3–3. DOE/NNSA will pursue advanced manufacturing areas for investments across capabilities 

that support a robust and resilient manufacturing capability ........................................................... 3-22 

Figure 3–4. Interdependent components of the Weapon Modeling and Simulation portfolio ........................... 3-24 

Figure 3–5. Confined Large Optical Scintillator Screen and Imaging System (CoLOSSIS) ..................................... 3-46 

Figure 3–6. Physical security composition ............................................................................................................ 3-50 

Figure 3–7. Information Technology and Cybersecurity Capability core functions .............................................. 3-52 

Figure 4–1. Critical Decision overview .................................................................................................................... 4-2 

Figure 4–2. DOE/NNSA 25-year programmatic line-item schedule for projects included in the 

FY 2021 President’s Budget Request (FY 2021–FY 2025) .................................................................... 4-3 

Figure 4–3. DOE/NNSA 25-year programmatic line-item schedule for proposed projects 

(FY 2026–FY 2045) ............................................................................................................................... 4-4 

Figure 4–4. DOE/NNSA 25-year mission-enabling infrastructure line-item schedule ............................................ 4-5 

Figure 4–5. Total M&O workforce by Common Occupational Classification System ............................................. 4-7

Figure 4–6. M&O separations in FY 2018 and FY 2019 ........................................................................................... 4-8 

Figure 4–7. M&O separations by years of service .................................................................................................. 4-8 

Figure 4–8. M&O separations by age ..................................................................................................................... 4-9 

Figure 5–1. FY 2020 – FY 2021 Weapons Activities Budget Structure Comparison ................................................ 5-2 

Figure 5–2. Funding schedule for Stockpile Management, FY 2020 – FY 2025 ...................................................... 5-4 

Figure 5–3. Key milestones for Stockpile Management ......................................................................................... 5-6 

Figure 5–4. Funding schedule for Production Modernization, FY 2020 – FY 2025 ................................................. 5-7 

Figure 5–5. Key milestones for Production Modernization .................................................................................. 5-11 

Figure 5–6. Funding schedule for Stockpile Research, Technology, and Engineering, FY 2020 – FY 2025 ........... 5-12 

Figure 5–7. Key milestones for Stockpile Research, Technology, and Engineering .............................................. 5-15 

Figure 5–8. Funding schedule for Infrastructure and Operations, FY 2020 – FY 2025 ......................................... 5-16 

Figure 5–9. Funding schedule for Other Weapons Activities, FY 2020 – FY 2025 ................................................ 5-20 

Figure 5–10. Key milestones for Secure Transportation Asset ............................................................................... 5-21 

Figure 5–11. Key milestones for Defense Nuclear Security .................................................................................... 5-22 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page E-2 

Figure 5–12. Key milestones for Information Technology and Cybersecurity ........................................................ 5-23 

Figure 5–13. Cost estimates across the Phase 6.x Process ..................................................................................... 5-25 

Figure 5–14. B61-12 Life Extension Program cost from FY 2012 to completion .................................................... 5-29 

Figure 5–15. W88 Alteration 370 (with conventional high explosive refresh) from FY 2013 to completion ......... 5-30 

Figure 5–16. W80-4 Life Extension Program cost from FY 2015 to completion ..................................................... 5-31 

Figure 5–17. W87-1 Modification Program cost from FY 2019 to completion ....................................................... 5-33 

Figure 5–18. Total U.S. projected nuclear weapons life extension costs for FY 2020 – FY 2045 

with high and low estimates (then-year dollars) ............................................................................... 5-35 

Figure 5–19. Projected out-year budget estimates for DOE/NNSA Weapons Activities in then-year dollars 

with high- and low-cost estimates, including the escalated President’s Budget Request ................ 5-39 

Figure B–1. Exascale Computing Project integrated project team ........................................................................ B-4 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page E-3 

List of Tables 

Table 1–1. Current U.S. nuclear weapons and associated delivery systems ......................................................... 1-3 

Table 2–1. Summary of W88 Alteration 370 Program challenges and strategies ................................................. 2-7 

Table 2–2. Summary of B61-12 Life Extension Program challenges and strategies .............................................. 2-8 

Table 2–3. Summary of W80-4 Life Extension Program challenges and strategies .............................................. 2-9 

Table 2–4. Summary of W87-1 Modification Program challenges and strategies ................................................ 2-9 

Table 2–5. Summary of Weapons Dismantlement and Disposition challenges and strategies .......................... 2-11 

Table 2–6. Summary of Production Operations challenges and strategies ......................................................... 2-12 

Table 3–1. Summary of Plutonium Handling, Packaging, and Processing challenges and strategies ................... 3-6 

Table 3–2. Summary of Highly Enriched Uranium Handling, Packaging, and Processing 

challenges and strategies..................................................................................................................... 3-8 

Table 3–3. Summary of Depleted Uranium Handling, Packaging, and Processing challenges and strategies ...... 3-9 

Table 3–4. Summary of the Domestic Uranium Enrichment Handling, Packaging, Processing, and 

Manufacturing challenges and strategies .......................................................................................... 3-10 

Table 3–5. Summary of the Tritium Production, Handling, and Processing challenges and strategies .............. 3-12 

Table 3–6. Summary of Energetic and Hazardous Materials Handling, Packaging, Processing, and 

Manufacturing (HE and Lithium) challenges and strategies .............................................................. 3-13 

Table 3–7. Summary of the High Explosives Handling, Packaging, Processing, and Manufacturing 

challenges and strategies................................................................................................................... 3-14 

Table 3–8. Summary of Lithium Handling, Packaging, and Processing challenges and strategies ...................... 3-16 

Table 3–9. Summary of Non-Nuclear Component Production challenges and strategies .................................. 3-18 

Table 3–10. Summary of Weapon Component and Material Process Development 

challenges and strategies................................................................................................................... 3-19 

Table 3–11. Summary of Weapon Component and System Prototyping challenges and strategies .................... 3-21 

Table 3–12. Summary of Advanced Manufacturing challenges and strategies .................................................... 3-22 

Table 3–13. Summary of Weapon Simulation and Computing portfolio challenges and strategies ..................... 3-25 

Table 3–14. Summary of Weapons Physics Design and Analysis challenges and strategies ................................. 3-27 

Table 3–15. Summary of Weapons Engineering Design, Analysis, and Integration challenges and strategies ..... 3-28 

Table 3–16. Summary of Environmental Effects Analysis, Testing, and Engineering Sciences 

challenges and strategies................................................................................................................... 3-29 

Table 3–17. Summary of Weapons Surety Design, Testing, Analysis, and Manufacturing 

challenges and strategies................................................................................................................... 3-30 

Table 3–18. Summary of Radiation-Hardened Microelectronics Design and Manufacturing 

challenges and strategies................................................................................................................... 3-31 

Table 3–19. Summary of Nuclear Physics and Engineering challenges and strategies ......................................... 3-32 

Table 3–20. Summary of Radiochemistry challenges and strategies .................................................................... 3-33 

Table 3–21. Summary of Atomic and Plasma Physics challenges and strategies .................................................. 3-34 

Table 3–22. Summary of High Energy Density Physics challenges and strategies ................................................ 3-35 

Table 3–23. Summary of Laser and Optical Science, Technology, and Engineering challenges and strategies .... 3-36 

Table 3–24. Summary of Accelerator and Pulsed Power Science, Technology, and Engineering 

challenges and strategies................................................................................................................... 3-37 

Table 3–25. Summary of Advanced Experimental Diagnostics and Sensors challenges and strategies ............... 3-39 

Table 3–26. Summary of Hydrodynamic and Subcritical Experiments challenges and strategies ........................ 3-40 

Table 3–27. Summary of Chemistry and Chemical Engineering challenges and strategies .................................. 3-41 

Table 3–28. Summary of High Explosives and Energetic Science and Engineering challenges and strategies ..... 3-42 

Table 3–29. Summary of Materials Science and Engineering challenges and strategies ...................................... 3-43
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page E-4 

Table 3–30. Summary of Weapon Assembly, Storage, and Disposition challenges and strategies ...................... 3-45 

Table 3–31. Summary of Testing Equipment Design and Fabrication challenges and strategies ......................... 3-46 

Table 3–32. Summary of Weapon Component and System Surveillance and Assessment 

challenges and strategies................................................................................................................... 3-47 

Table 3–33. Summary of Secure Transportation challenges and strategies ......................................................... 3-49 

Table 3–34. Physical Security status ...................................................................................................................... 3-50 

Table 3–35. Summary of Physical Security challenges and strategies .................................................................. 3-51 

Table 3–36. Information Technology and Cybersecurity status ........................................................................... 3-53 

Table 3–37. Summary of Information Technology and Cybersecurity challenges and strategies ......................... 3-54 

Table 5–1. Overview of Future Years Nuclear Security Program budget request for 

Weapons Activities in FY 2020 – FY 2025 ............................................................................................ 5-3 

Table 5–2. DOE/NNSA deferred maintenance as a percentage of Replacement Plant Value............................. 5-19 

Table 5–3. Projected FY 2021 DOE/NNSA infrastructure maintenance and recapitalization investments ......... 5-19 

Table 5–4. Cost estimates for life extension programs and major alterations within the 

25-year program of record ................................................................................................................ 5-27 

Table 5–5. Total actual cost for W76-1 Life Extension Program ......................................................................... 5-28 

Table 5–6. Total estimated cost for W76-2 Modification Program ..................................................................... 5-28 

Table 5–7. Total estimated cost for B61-12 Life Extension Program .................................................................. 5-29 

Table 5–8. Total estimated cost for W88 Alteration 370 (with conventional high explosive refresh) 

Program ............................................................................................................................................. 5-31 

Table 5–9. Total estimated cost for W80-4 Life Extension Program ................................................................... 5-32 

Table 5–10. Total estimated cost for W87-1 Modification Program ..................................................................... 5-33 

Table 5–11. Total estimated cost for W93 ............................................................................................................ 5-34 

Table 5–12. Total estimated cost for Future Strategic Missile – Land-Based Warhead ........................................ 5-34 

Table 5–13. Total estimated cost for Future Strategic Missile – Sea-Based Warhead .......................................... 5-34 

Table 5–14. Total estimated cost for B61 Follow-On ............................................................................................ 5-35 

Table 5–15. Cost Estimate Classification System .................................................................................................. 5-37 

Table 5–16. Weapons Activities capital acquisition estimated costs, FY 2021 – FY 2045 ..................................... 5-37 

Table B–1. NNSA Exascale Computing Initiative funding schedule for FY 2021 through 2025 ............................ B-2 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page F-1 

Appendix F 

Acronyms and Abbreviations 

AF&F arming, fuzing, and firing 

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 

CAP Capital Acquisition Planning 

CD Critical Decision 

CMR Chemistry and Metallurgy Research 

CoLOSSIS Confined Large Optical Scintillator Screen and Imaging System 

CORAL Collaboration of Oak Ridge National laboratory, Argonne National Laboratory, 

and Lawrence Livermore National Laboratory 

COTS commercial off-the-shelf 

CREST Combined Radiation Environments for Survivability Testing 

CSSE Computational Systems and Software Environment 

CUAS counter unmanned aircraft systems 

DARHT Dual-Axis Radiographic Hydrodynamic Test 

DM deferred maintenance 

DNS Office of Defense Nuclear Security 

DoD Department of Defense 

DOE Department of Energy 

DUF6 depleted uranium hexafluoride

ECFM Exascale Computing Facility Modernization 

ECP Exascale Computing Project 

ECSE Enhanced Capabilities for Subcritical Experiments 

ESC Enterprise Secure Computing 

FY fiscal year 

FYNSP Future Years Nuclear Security Program 

GAO Government Accountability Office 

GTS gas transfer system 

HE high explosives 

HED high energy density 

HERMES High-Energy Radiation Megavolt Electron Source 

HEU highly enriched uranium 

HOT SHOT High Operational Tempo Sounding Rocket Program 

HPC high performance computing 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page F-2 

ICF inertial confinement fusion 

IDCs integrated design codes 

IMI Infrastructure Modernization Initiative 

IT information technology 

JTA joint test assembly 

KCNSC Kansas City National Security Campus 

LANL Los Alamos National Laboratory 

LANSCE Los Alamos Neutron Science Center 

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 

M/U margin to uncertainty 

MB Management and Budget 

MESA Microsystems Engineering, Science and Applications 

MFFF Mixed Oxide Fuel Fabrication Facility 

MGT Mobile Guardian Transporter 

Mod modification 

NEPA National Environmental Policy Act 

NSCI National Strategic Computing Initiative 

NMI Nuclear Materials Integration 

NNSA National Nuclear Security Administration 

NSCI National Strategic Computing Initiative 

OMB Office of Management and Budget 

Pantex Pantex Plant 

PIDAS Perimeter Intrusion Detection and Assessment System 

R&D research and development 

RD restricted data 

RDT&E research, development, test and evaluation 

RPV replacement plant value 

SAR Selected Acquisition Report 

SCE Subcritical Experiments 

SFI significant finding investigation 

SGT Safeguards Transporter 

SIRP Security Infrastructure Revitalization Program 

SLCM-N Sea-Launched Cruise Missile 

SNL Sandia National Laboratories 

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 
Department of Energy/National Nuclear Security Administration | December 2020

Fiscal Year 2021 Stockpile Stewardship and Management Plan – Biennial Plan Summary | Page F-3 

ST&E science, technology, and engineering 

STA Secure Transportation Asset 

STS stockpile-to-target sequence 

TPBARs tritium-producing burnable absorber rods 

TVA Tennessee Valley Authority 

U.S. United States 

U.S.C. United States Code 

USSTRATCOM U.S. Strategic Command 

WDCR Weapon Design and Cost Report 

WDD Weapons Dismantlement and Disposition 

Y-12 Y-12 National Security Complex 

Z Z pulsed power facility 




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National Nuclear Security Administration 

1000 Independence Avenue, SW 

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DOE/NA-0110