1

Introduction

1.1 STUDY TASK

The National Academies of Sciences, Engineering, and Medicine (the National Academies) were tasked with undertaking an independent review and assessment of U.S. capabilities for detection, verification, and monitoring of nuclear weapons and fissile material in the fiscal year (FY) 2020 National Defense Authorization Act (NDAA). Section 3136 of the FY2020 NDAA specified that the review and assessment include

• an evaluation of the current national research enterprise for detection, verification, and monitoring of nuclear weapons and fissile material;
• an evaluation of the integration of roles, responsibilities, and planning for such detection, verification, and monitoring within the federal government;
• opportunities to leverage the national research enterprise to further prevent the proliferation of nuclear weapons and fissile material, including with respect to policy, research and development, and testing and evaluation;
• opportunities for international engagement for building cooperation and transparency, including bilateral and multilateral efforts, to improve inspections, detection, and monitoring of nuclear weapons and fissile material, and to create incentives for such cooperation and transparency;
• opportunities for new or expanded research and development efforts to improve detection and monitoring of, and in-field inspection and analysis capabilities with respect to, nuclear weapons and fissile materials;

• opportunities for improved coordination between departments and agencies of the federal government and the military departments, national laboratories, commercial industry, and academia; and
• opportunities for leveraging commercial capabilities.

The congressional mandate to the National Academies followed multiple congressional requests to the National Nuclear Security Administration (NNSA) to provide a detailed monitoring and verification plan, motivated in part by a 2014 Defense Science Board (DSB) Task Force report, Assessment of Nuclear Monitoring and Verification Technologies (DSB, 2014).¹ The 2014 DSB report included an assessment of the technical needs to support nuclear proliferation monitoring within both cooperative and unilateral constructs. A summary of the conclusions of the DSB Task Force is presented in Appendix C.

Following the completion of the DSB study, Congress tasked NNSA in Section 3133 of the FY2015 NDAA with submitting a plan for monitoring and verification of the proliferation of nuclear weapons and fissile material. In response, NNSA submitted a brief, two-page classified plan to congressional committees that, according to the Government Accountability Office (GAO), lacked the specific details requested (GAO, 2018a). In Section 3132 of the FY2017 NDAA, Congress tasked NNSA with providing an updated plan. A four-page classified plan update submitted to Congress by NNSA in response was again found to fail to address any of the reporting requirements in sufficient detail (GAO, 2018a).

In response, Congress noted in Section 3136 of the FY2018 NDAA that NNSA’s previous submissions “do not reflect the priority” of verification, detection, and monitoring of nuclear weapons and fissile materials, and once again required NNSA to submit a more detailed plan. In April 2018, NNSA provided a longer unclassified plan and classified annex to congressional committees. The unclassified plan is summarized in Appendix D. A subsequent GAO report (GAO, 2018b) found that while this plan “provided details on most of the reporting requirements,” it “did not include information on future costs and funding needs.” In the FY2020 NDAA, Congress directed NNSA to ask the National Academies to conduct an independent review of the topic.

1.2 REPORT SCOPE AND ORGANIZATION

Monitoring, detection, and verification (MDV) (see Box 1-1 for definitions) techniques and technologies are tools designed to detect the signatures and observables of nuclear proliferation and detect and deter non-compliance with agreements and treaties. MDV for proliferation or arms control involves both cooperative MDV with other state(s) and MDV conducted by the U.S. government alone. Capabilities for both cooperative and unilateral MDV are addressed in this study.

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¹ Hereafter referred to as the 2014 DSB report.

The MDV mission space is often broken into the two distinct spheres of proliferation detection and arms control. However, there is a case to be made for treating MDV as a cohesive mission. First, while the goals and technical requirements of monitoring for proliferation detection and arms control treaty compliance might differ, there is significant overlap among the technical capabilities employed (e.g., radiation detection, remote sensing, containment and surveillance measures, authentication, advanced data analysis). Furthermore, the lines between the mission areas begin to blur as one contemplates future nonproliferation and arms reduction outcomes. For example, verification of a Fissile Material Cutoff Treaty² would likely be an evolution of international safeguards,

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² For more information on the proposed fissile material cut-off treaty, see Arbman (1998) and Arms Control Association (2018).

and nuclear disarmament would not be credible without being able to verify the final disposition of nuclear material and other warhead components.

In order to assess the integration of roles, responsibilities, and planning in the MDV enterprise, the committee has reviewed efforts undertaken by the Department of Energy (DOE/NNSA), Department of Defense (DoD), Department of State (DoS), and the intelligence community (IC),³ as well as the DOE national laboratories and relevant academic and commercial communities. In addition, the committee has considered the contributions to this mission space made by the two most relevant international organizations, the International Atomic Energy Agency (IAEA) and Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The NNSA Office of Defense Nuclear Nonproliferation (DNN) is the biggest funder of U.S. MDV research, development, test, and evaluation (RDT&E) and was therefore a special area of focus for this study.

This interim report is organized in four chapters. The remainder of Chapter 1 summarizes current security challenges that motivate MDV needs, makes the case that MDV should be a key national priority, and outlines the roles and responsibilities of the various departments, agencies, and organizations that make up the MDV enterprise. Chapter 2 presents the committee’s findings and recommendations related to governance of the MDV enterprise. Chapter 3 offers findings and recommendations related to technical MDV capabilities and RDT&E efforts, focused in particular on the nuclear fuel cycle, nuclear test explosions, and arms control. Finally, Chapter 4 offers brief over-arching conclusions. Table 1-1 indicates which section(s) of the report address each of the study task components outlined in the FY2020 NDAA.⁴

1.3 CURRENT SECURITY CHALLENGES FOR NONPROLIFERATION AND ARMS CONTROL

The 2014 DSB report noted that the nuclear threat environment has changed in significant ways (DSB, 2014):

• The number of actors and geographic areas of concern go beyond those targeted by monitoring for treaty compliance.
• The countries pursuing and considering nuclear programs pose grave national security risks—and the numbers continue to grow.
• U.S. adversaries are modernizing their arsenals, in some nontraditional ways.
• The need to detect clandestine materials/production capabilities is magnified, particularly as disarmament efforts are pursued.

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³ The committee will assess efforts undertaken by the IC in more detail in the final report.

⁴ National Defense Authorization Act, 116th Congress, § 3136 (2020).

TABLE 1-1 Mapping of Study Task Components to Sections of the Report

The DSB Task Force further noted that “for the first time since the early decades of the nuclear era, the nation needs to be equally concerned about both ‘vertical’ proliferation (the increase in capabilities of existing nuclear states) and ‘horizontal’ proliferation (an increase in the number of states and non-state actors possessing or attempting to possess nuclear weapons)” (DSB, 2014, p. 13).

Many of the concerns identified by the DSB Task Force are still relevant today, and some additional challenges have arisen since that time. Building on the 2014 DSB report, the committee notes several specific national security challenges that require improved MDV capabilities.⁵

1. Russia and China continue to modernize their arsenals.

U.S. national security policy documents note that Russia and China continue to develop advanced nuclear capabilities (White House, 2017; DoD, 2018).

Although its arsenal has been significantly reduced through a series of negotiated bilateral nuclear arms control agreements, Russia maintains a large nuclear arsenal. In addition to its arsenal of intercontinental ballistic missiles, long range bombers, ballistic missile submarines, and tactical nuclear systems, Russia is developing new ways to deliver nuclear weapons that include hypersonic missiles, nuclear-powered autonomous torpedoes, and nuclear-powered cruise missiles (Hruby, 2019).

The only remaining bilateral nuclear arms control agreement, New START, was recently extended for five years and will now expire on February 5, 2026.

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⁵ While these challenges are significant, it is also important to note that the Nuclear Nonproliferation Treaty (NPT) has proven surprisingly durable since the landmark international treaty entered into force in 1970, and a feared proliferation cascade has not materialized. Over the past several decades, one state (South Africa) gave up nuclear weapons it developed, three states gave up weapons they inherited in the collapse of the Soviet Union (Ukraine, Kazakhstan, and Belarus), and three states (India, Pakistan, and North Korea) acquired them. Proliferation programs in Iraq, Libya, and Syria have ended. Iran remains a concern, and if it acquires nuclear weapons, it could spark others in the region to attempt to do so. Moreover, the credibility of U.S. extended deterrence remains a key factor in the commitment of many U.S. allies to the NPT.

Although some progress has been made on a framework for the next agreement, which may encompass all nuclear warheads, further cooperative nuclear arms control between the United States and Russia will be challenging because each country has conditions inimical to the other country. The challenges are not just political; warhead verification is a distinct and more challenging task than verifying delivery vehicles or the absence of nuclear weapons on delivery systems, as is done under New START now. Verifying warheads under an arms control framework without revealing sensitive information will require different technologies and processes than are currently in place (DSB, 2014).

China is also modernizing and expanding its nuclear arsenal (DoD, 2018). A recent U.S. government assessment indicates that China seeks to double its total number of nuclear weapons from about 200 to about 400 (DoD, 2020). In addition to its growing nuclear arsenal, China is improving its nuclear weapon delivery systems and maintains dual-capable short- and intermediate-range missiles (able to be either nuclear or conventionally armed). Dual-capable systems pose a significant MDV challenge because external observations cannot necessarily determine whether the system is armed with a nuclear or conventional warhead, which makes them a special proliferation risk and particularly troublesome with respect to any arms control agreement. China has never been party to any bilateral arms control agreement with the United States and has indicated little willingness to participate in cooperative nuclear arms control. Although China has participated in the P5 process with the other NPT nuclear weapon states,⁶ a bilateral or trilateral (with Russia) cooperative arms control negotiation process would take considerable political will on all sides. If the negotiation includes verification measures, it will likely be long and complex, akin to U.S.-Soviet negotiations during the Cold War.

2. India and Pakistan remain adversaries in a tense environment.

India and Pakistan remain nuclear-armed states outside of the NPT. Recent reports state that India is considering abandoning its long-held no-first-use policy in response to Pakistan’s lack of a no-first-use pledge and provocations by China (Pant and Joshi, 2020). India is also improving its long-range nuclear missile capabilities to hold more of China at risk (Tellis, 2019).

To defend against invasion from a numerically superior Indian conventional army, Pakistan positions nuclear weapons close to the Indian border on the rationale that they could be used, perhaps on Pakistani territory, in the early stages of a war with India (Dalton and Perkovich, 2016). India has said that use of nuclear weapons against Indian forces, wherever they are, would be first-use and could trigger a nuclear retaliation. The posture of Pakistani nuclear forces makes the security and command-and-control of these weapons challenging and amplifies

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⁶ The five nuclear weapons states recognized by the NPT are the United States, Russia, the United Kingdom, France, and China.

the urgency of a “use-or-lose” decision in a conflict with India (Dalton and Perkovich, 2016; Tasleem, 2016).

Both Pakistan and India have suffered terrorist attacks on their military facilities. The A. Q. Khan network transferred Pakistani nuclear weapons–related technology to several countries.

3. North Korea continues to refine and improve its nuclear weapons and long-range delivery capabilities.

Reports indicate that North Korea continues to produce fissile material for its nuclear arsenal and may be developing smaller nuclear warheads and longer-range missiles capable of carrying multiple warheads to every part of the United States (Hecker et al., 2020). The 2018 Nuclear Posture Review also notes the risks of North Korea selling weapons or nuclear technology to other states or non-state actors (DoD, 2018). Recent efforts to convince North Korea to limit or abandon its nuclear arsenal have failed to freeze or reduce North Korea’s nuclear capabilities. The growth of the North Korean nuclear arsenal from a handful of weapons to dozens, with long-range delivery capabilities, changes the nature of the threat.

4. Future constraints on Iran’s nuclear program are uncertain.

Following U.S. withdrawal from the Joint Comprehensive Plan of Action (JCPOA) in May 2018 (White House, 2018), Iran has increased its stockpile of enriched uranium, the level of enrichment, and the number and types of centrifuges it is operating (BBC News, 2020b). Iran’s stockpile of low-enriched uranium now significantly exceeds JCPOA limits,⁷ although the stockpile has not approached pre-JCPOA levels. The IAEA recently confirmed that Iran is building a new underground centrifuge assembly facility after a previous facility exploded in July 2020, claimed by Iran to be an act of sabotage (BBC News, 2020a). Still, the IAEA monitoring and verification mission in Iran has continued, and the agency retains the extraordinary access it has only through the authority of the JCPOA.

5. Several actors have latent nuclear capability or may have motivations to develop their own nuclear weapons.

North East Asia remains a tense regional environment as China has increased its military spending and regional dominance and North Korea continues to develop new military capabilities. At the same time, the influence of the United States in this region has weakened as trust in U.S. security guarantees

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⁷ As of November 12, 2020, Iran’s enriched uranium stockpile was 12 times the JCPOA limit, according to the IAEA (BBC News, 2020b).

has diminished (Lee, 2019). South Korea, Japan, and Taiwan all have advanced nuclear power programs and could develop a nuclear weapon capability if the political decision were made (Kassenova, 2012). Taiwan and South Korea pursued nuclear weapons programs several decades ago (Bush, 2011), and a majority of the South Korean public supports developing a domestic nuclear weapon program, although this majority appears to have shrunk recently (Park, 2016; Smeltz et al., 2019).

There is also the potential for proliferation in the Middle East. Saudi Arabia has publicly stated that it will seek to develop nuclear weapons if Iran acquires them (Sanger, 2015). In addition, although Turkey is a member of the North Atlantic Treaty Organization, President Erdogan suggested recently that it is “unfair” that Turkey cannot have its own nuclear weapons (Reuters, 2019).

6. Nuclear energy programs, including enrichment and reprocessing capabilities, are being pursued by states with unclear commitments to nonproliferation.

In its FY2020–2024 Plan to Reduce Global Nuclear Threats,⁸ NNSA notes concerns about nuclear proliferation if energy needs promote a resurgence in civilian nuclear power in states “whose commitment to nonproliferation is uncertain” (NNSA, 2019). For example, under leader Jair Bolsonaro, Brazil has announced plans to grow its nuclear program and expand its enrichment capacity (Spektor et al., 2019). Furthermore, Eduardo Bolsonaro, Jair Bolsonaro’s son, has suggested that Brazil would benefit from a nuclear arsenal (Mann, 2019). The spread of enrichment and reprocessing capabilities is a particular proliferation concern, especially in countries like Saudi Arabia that do not have 123 Agreements⁹ with the United States that stipulate nonproliferation norms.¹⁰

7. Nuclear weapons technology and expertise is widely available and easier to disseminate.

Nuclear weapon design and production knowledge is increasingly widespread, and information is becoming more difficult to control.¹¹ Nuclear programs can develop more quickly if proliferators pool their resources and capabilities. The state-linked A. Q. Khan network shows that proliferation detection efforts

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⁸ This document is hereafter referred to as the FY2020–2024 NNSA Plan.

⁹ For more information on 123 Agreements, see DOE (2020a).

¹⁰ Negotiations between the United States and Saudi Arabia on nuclear energy cooperation, which date back to 2008, have stalled over disagreements on several nonproliferation conditions, including Saudi Arabia agreeing to enrichment and reprocessing restrictions (GAO, 2020). The Wall Street Journal recently reported that Saudi Arabia has constructed a uranium processing facility with the help of China (Strobel et al., 2020).

¹¹ The recently revealed Iran Nuclear Archive also shows evidence of foreign participation in nuclear weapon design (Arnold et al., 2019).

should not only be focused on individual states. In addition, the desire of terrorist organizations to acquire and use a nuclear device to attack the United States or its allies has been widely reported.¹² Since well before the attacks of September 11, 2001, the U.S. government has worked to prevent the acquisition of nuclear weapons or material by non-state actors.¹³

8. Technology advancements may create new pathways to nuclear weapons.

NNSA notes that “scientific advances and manufacturing improvements . . . may create new pathways to nuclear weapons” (NNSA, 2019b). Small-scale nuclear material processing and additive manufacturing is easier to hide, and alternative fuel cycles could be developed and improved. Monitoring these new pathways will be challenging, as their signatures are unknown, and their small scale may be unobservable with current MDV technologies.

9. Public access to data and the role of open-source information are increasing.

The past few years have seen a significant increase in the amount of public data that may be relevant to monitoring nuclear weapons and civilian nuclear programs (e.g., commercial satellite images, open-source seismic sensor networks). The increasing quantity and varied quality of public information will create new dynamics, such as rapid and incomplete release of information, public speculation, and societal pressure, that could take diplomatic options off the table or drive adversaries to better conceal their activities. On the other hand, commercial technologies can provide government analysts with data and information that are complementary to government-owned capabilities.

10. Bias and assumptions when assessing proliferation risks may hinder monitoring efforts.

It is easy to assume that proliferators would use similar technology and make similar choices to the United States to produce a weapon. However, there are examples of states using different approaches to establishing a nuclear weapons capability. For example, Iraq built calutrons for uranium enrichment not because they were efficient or economical but because the knowledge and technology was

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¹² For example, the final report of the 9/11 Commission noted in 2004 that “Al Qaeda has tried to acquire or make nuclear weapons for at least ten years . . . and continues to pursue its strategic goal of obtaining a nuclear capability” (NCTAUUS, 2004, p. 380). For additional information, see Allison (2004).

¹³ Efforts by the U.S. government to attribute a non-state actor nuclear or radiological attack are addressed by other National Academies reports. See NASEM (2010, 2021).

available (Erkman et al., 2008). New reactor fuels and other new fuel cycle technologies will likely become more relevant going forward. In addition, the need to conduct a nuclear test may be diminishing since a proliferator may choose to rely on known simplistic designs, computer simulations, and/or gifted or stolen information. Furthermore, other governments or subnational groups may tolerate greater uncertainty about performance of a nuclear explosive than does the United States. Assuming that proliferators will make similar choices to the United States may lead analysts to overlook nonsimilar activities.

1.4 APPROACHING MDV AS A KEY PRIORITY

To meet the challenges listed above, MDV of nuclear weapons and weapons-usable material must be a higher national priority with more support and attention than it currently receives. The MDV mission space has not been consistently prioritized over the years, and Box 1-2 gives two examples of how the lack of

support and attention has impacted the national and international capabilities for this mission. This assessment is consistent with the DSB Task Force’s conclusion that given the current threat environment, “monitoring for proliferation should be a top national security objective—but one for which the nation is not yet organized or fully equipped to address” (DSB, 2014, p. 2). While MDV capabilities have advanced since the 2014 DSB report, the priority and level of R&D effort has not increased commensurate with the expanding, multipolar nuclear threat.

A sustained and prioritized MDV program should fulfill three critical mission functions: (1) stewardship of capabilities, (2) meeting future capability needs, and (3) minimizing surprise. Figure 1-1 shows how these functions support each other. For example, the United States needs to maintain a robust scientific and technological foundation to minimize technology surprise. In addition, the enterprise must anticipate future threats in order to identify early what R&D to invest in to meet future technical needs. The recommendations made by the committee in this report, if implemented, will strengthen these mission functions. The relationship between each recommendation and these functions is presented in Appendix B.

The recommendations made in this report are largely directed to the departments and agencies that form the MDV enterprise (see Section 1.5 below). It is important to note that in order to implement the report recommendations, the

MDV enterprise will need additional and sustained funding.¹⁴ MDV R&D efforts must be sustained over long periods of time to advance capabilities. Large fluctuations in funding can lead to a loss of talent and capabilities, increase overall costs, and hinder the ability to deliver technologies when needed. In addition, sustained operation and maintenance funding is necessary to ensure that key operational capabilities are preserved and modernized as appropriate to prevent loss of functionality.

1.5 OVERVIEW OF ROLES AND RESPONSIBILITIES

The MDV mission is distributed across a number of federal agencies and departments and international organizations, each of which has a unique and important role. Figure 1-2 shows key agencies and offices involved in the MDV enterprise, sorted into the type of role they play: (1) policy and coordination, (2) RDT&E, and (3) operations. The committee did not find inappropriate duplication of activities.

DOE/NNSA is the primary funder for MDV RDT&E (in particular DNN R&D, which has an annual MDV RDT&E budget of more than $500 million).¹⁵ DoD, DoS, and the Department of Homeland Security (DHS) have much smaller MDV RDT&E budgets (on the order of $10 to 50 million annually, as shown in Table 1-2, which summarizes the key MDV RDT&E organizations, their RDT&E focuses, and the technology readiness levels [TRLs]¹⁶ of their capabilities). DoS leads policy development and analysis, and DoD plays a critical operational role, in particular through the Defense Threat Reduction Agency (DTRA) and Air Force Technical Applications Center (AFTAC). The IC also plays a key role that the committee will address in more detail in the final report. Finally, the United States is also a member of international organizations that have important MDV roles.

The remainder of this section briefly outlines the roles and responsibilities of all of these key organizations, organized roughly by predominant functions as shown in Figure 1-2. Further assessment of how these organizations interact with each other is presented in later sections of this report.

1.5.1 National Security Council

Nuclear arms control and nonproliferation policies are core U.S. national security issues that have historically received considerable and sustained attention

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¹⁴ The amount of additional funding necessary to implement the report recommendations is an open question that the committee will revisit in the final report after additional data gathering.

¹⁵ The DOE national laboratories are the primary MDV R&D providers. See Appendix G for a description of MDV efforts at five DOE laboratories that play significant roles in the MDV enterprise.

¹⁶ See Appendix E for a description of each TRL.

from the president and the National Security Council (NSC).¹⁷ The NSC staff typically lead an interagency process to develop these policies and prepare instructions for arms control and nonproliferation negotiators. The NSC staff,

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¹⁷ The NSC is a statutorily established body chaired by the President. The participants of the NSC vary by presidential administration, but generally include the Vice President, the National Security Advisor, and the Secretaries of State, Defense, and Treasury. Other agency and department heads are invited to participate as needed. In practice, most usage of the term NSC, including usage in this report, is shorthand for the NSC staff acting on behalf of the NSC.

TABLE 1-2 Summary of Key MDV RDT&E Organizations with Approximate Annual Funding Levels and Key Focuses

however, have generally been less involved in creating and implementing a process to formulate monitoring and verification technology requirements and to identify research and development programs to meet them.

1.5.2 National Science and Technology Council, Office of Science and Technology Policy

The Office of Science and Technology Policy also plays a role in interagency MDV coordination through the National Science and Technology Council. In particular, the Nuclear Defense Research and Development Subcommittee of the council’s Committee on Homeland and National Security develops nuclear defense¹⁸ strategic R&D plans with input from relevant agencies. This process is discussed in more detail in Section 2.1.3.

1.5.3 Department of State

DoS leads nonproliferation and arms control policy implementation in the diplomatic realm, including verification and compliance judgments. DoS is also the primary funder of the United States Support Program (USSP) to IAEA

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¹⁸ The scope of “nuclear defense” includes MDV.

safeguards. The two DoS bureaus that contribute significantly to the MDV are described below.

Bureau of Arms Control, Verification, and Compliance

The Bureau of Arms Control, Verification, and Compliance (AVC) is the government’s lead agency on cooperative arms control and nonproliferation treaties.¹⁹ AVC is congressionally mandated to provide an annual report assessing compliance and adherence of both the United States and other nations to arms control, nonproliferation, and disarmament agreements and commitments (AVC, 2020). In line with its verification focus, AVC is responsible for overseeing the Key Verification Assets Fund (V Fund), which provides small amounts of seed funding to researchers to help preserve critical assets or develop innovative new technologies.²⁰ In FY20, the AVC Fund allocated $11.1 million for nuclear verification R&D.

Bureau of International Security and Nonproliferation

The Bureau of International Security and Nonproliferation (ISN) works closely with the IAEA on nuclear safeguards issues, pursuant to NPT obligations. ISN’s responsibilities include overseeing the cooperative tools, training, expertise, and analysis necessary to successfully conduct on-site monitoring and detect undeclared nuclear facilities. In this role, ISN works closely with the NNSA Office of Nonproliferation and Arms Control (NPAC) Office of Nuclear Verification. ISN is also responsible for overseeing the Nonproliferation and Disarmament Fund, which provides a means for the United States to respond rapidly to vital nonproliferation and disarmament opportunities, circumstances, or conditions that are unanticipated, transient, or unusually difficult (DoS, 2020, p. 92).²¹

United States Support Program to IAEA Safeguards and International Safeguards Project Office

The USSP funds R&D and provides technical support to the IAEA Department of Safeguards in the form of cost-free experts and junior professional

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¹⁹ However, DoS/ISN has the responsibility of working with the IAEA.

²⁰ For an example of research funded via the V Fund, see Coblentz and Pabian (2015).

²¹ DoS/ISN communicated to the committee that FY2020 Nonproliferation and Disarmament Fund funding supported weapons of mass destruction threat reduction in Syria, Egyptian counter-smuggling, nuclear safety and security in Latin America, expanded counter-smuggling efforts, global chemical and biological weapons prevention, and continued readiness to support the administration’s efforts to eliminate North Korea’s ballistic missile systems and nuclear weapons (DoS/ISN, communication to committee, November 18, 2020).

officers, training, and equipment. The USSP is primarily funded through the U.S. Program of Technical Assistance to IAEA Safeguards via DoS. The USSP is managed by the International Safeguards Project Office located at Brookhaven National Laboratory (BNL, n.d.). This office maintains staff in Vienna to facilitate direct contact with IAEA end users and effectively implement its programs.

1.5.4 Department of Energy/National Nuclear Security Administration Defense Nuclear Nonproliferation

NNSA DNN implements NNSA’s nonproliferation and arms control programs, and together with the Office of Defense Programs, formulates NNSA’s policy positions for the interagency nonproliferation and arms control decision-making process.

The Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D) and NPAC are the primary contributors to the MDV mission within NNSA DNN.²² Both DNN offices play a role in the MDV RDT&E process and provide MDV expertise to treaty negotiators and inspectors as needed. DNN R&D primarily funds early R&D (TRL 1 through TRL 4), while NPAC primarily funds technology development/maturation (TRL 5 and TRL 6) and interacts more directly with international end users like the IAEA.²³

Figure 1-3 shows the primary offices contributing to the MDV mission in DNN R&D and NPAC. A full DNN organizational chart in Appendix F includes additional offices that the committee did not focus on for this interim report.

Office of Defense Nuclear Nonproliferation Research and Development

The single largest MDV R&D effort is managed by DNN R&D, which has a $500+ million RDT&E portfolio, the bulk of which is directly relevant to the MDV mission (DNN R&D, communication to committee, September 18, 2020, and January 14, 2021). DNN R&D focuses primarily on R&D to improve

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²² DNN’s Office of Global Material Security and Office of Material Management and Minimization also support the MDV mission space. For example, the Office of Global Material Security houses NNSA’s Nuclear Smuggling Detection and Deterrence program, which works to improve nuclear detection capabilities abroad by deploying radiation detection systems and other tools and expertise (DOE, 2020b). The Office of Material Management and Minimization works to reduce weapons-usable nuclear material, which in turn reduces MDV needs. The committee did not focus on either of these offices in this interim study, since they are more indirectly involved in the MDV enterprise and do not exercise a significant role in fuel cycle monitoring, nuclear test explosion monitoring, or arms control monitoring, the technical areas that the committee focused on in this interim report.

²³ DNN R&D supports some higher TRL work (TRL 5 through TRL 9) to develop space-based nuclear detonation detection sensors for the Air Force (TRL 7 through TRL 9 signifies testing, demonstration, and implementation). NPAC’s RDT&E portfolio also includes limited work in TRL 2 through TRL 4 and in TRL 7 through TRL 9.

unilateral monitoring capabilities, although some R&D is intended to support cooperative international safeguards or arms control verification efforts.

As shown in Figure 1-3, DNN R&D is split into two sub-offices, the Office of Proliferation Detection (PD) and the Office of Nuclear Detonation Detection (NDD). The Office of Proliferation Detection carries out R&D to improve a broad range of nuclear-related MDV capabilities through three teams: Material Production Detection and Monitoring, Nuclear Weapons Development Detection and Material Security, and Nonproliferation Enabling Capabilities. Each team’s portfolios are shown in Figure 1-4.

PD primarily funds R&D at TRL 1 through TRL 4 and transitions capabilities to other organizations, such as NPAC, DTRA, AFTAC, and the IC, for further maturation. Most of the research funded by this office is carried out by the DOE national laboratories. For some projects, the DOE national laboratories work with industry, other federally funded research and development centers, and universities to accomplish their objectives. A small portion of the funding is provided to university-based consortia for both the intrinsic value of the research and the development of a capable talent pool.

NDD develops and builds satellite sensors for deployment by the Air Force to detect nuclear explosions globally, supporting research, development, and implementation through TRL 9. This office also includes a ground-based nuclear

detonation portfolio that supports low-TRL R&D to advance the understanding of waveform and RN signatures associated with nuclear detonations.²⁴ In addition, NDD conducts low-TRL R&D to advance nuclear forensics capabilities.²⁵ Its FY2020 budget was $196.6 million; $29.2 million of this total was allocated for R&D (TRL 1 through TRL 4), while the remainder was allocated to higher-TRL sensor development (DNN R&D, briefing to committee, November 3, 2020).

Office of Nonproliferation and Arms Control

While DNN R&D has a particular focus on R&D to support non-cooperative monitoring, the DNN NPAC has more of a focus on supporting end users and enabling cooperative monitoring and verification for safeguards and arms control. In addition, NPAC conducts RDT&E at higher TRLs than DNN R&D.

NPAC comprises four sub-offices: the Office of International Nuclear Safeguards, the Office of Nuclear Export Controls, the Office of Nuclear Verification, and the Office of Nonproliferation Policy. The Office of International Nuclear

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²⁴ This portfolio was recently moved to NDD from the Office of Proliferation Detection.

²⁵ Nuclear forensics, which is the topic of another National Academies report currently in preparation, was not an area of focus for this interim report.

Safeguards and the Office of Nuclear Verification contribute most directly to the MDV mission.²⁶

The primary mission of the Office of International Nuclear Safeguards is to support the IAEA. The office acts as a liaison to the IAEA and funds technology development (typically TRL 5 to TRL 6) with the goal of optimizing the effectiveness and efficiency of safeguards and improving the IAEA’s capability to detect non-compliance.²⁷ This technology development portfolio, which is funded at $20 to 25 million annually (NPAC, briefing to committee, November 18, 2020), primarily involves maturing prototype methods and technologies from R&D partners (in particular, DNN R&D) and readying them for international safeguards use. The Office of International Nuclear Safeguards also supports human capital development for the United States and international partners and policy development to advance IAEA safeguards implementation.

The Office of Nuclear Verification develops technologies and concepts of operation for on-site monitoring and verification of foreign nuclear facilities, maintaining readiness for short-notice deployments.²⁸ This office also identifies technology needs and supports technical development for MDV capabilities throughout the nuclear weapon lifecycle, including weapons deployed on delivery systems, weapons in storage, weapons in transport, and weapons being dismantled. In this work, it interfaces with international partners such as the U.K. (through the 1958 U.S.-U.K. Mutual Defense Agreement), the International Partnership for Nuclear Disarmament Verification,²⁹ and the Quad Nuclear Verification Partnership.³⁰ The Office of Nuclear Verification’s total technology

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²⁶ The other NPAC offices contribute more indirectly to the MDV mission and were not covered in detail in this study. The Office of Nuclear Export Controls “builds U.S. and global export control capacity to detect and prevent the illicit or inadvertent transfer of nuclear and dual-use materials, equipment, and technology” (NPAC, 2019). The Office of Nonproliferation Policy “develops technical and policy solutions to address enduring and emerging nonproliferation and arms control challenges and opportunities” (NPAC, 2019).

²⁷ The Office of International Nuclear Safeguards also currently chairs the Subgroup on Safeguards Technical Support, which has four sitting members, one each from DOE, DoS, DoD, and the Nuclear Regulatory Commission.

²⁸ The Office of Nuclear Verification’s Nuclear Compliance Verification Program led on-site verification and monitoring in Libya (2004) and North Korea (2007–2009). The committee did not assess this program in detail due to time constraints.

²⁹ The International Partnership for Nuclear Disarmament Verification comprises more than 25 countries and has the mission of developing, testing, and building support for multilateral nuclear disarmament verification approaches that include non-nuclear weapon possessing states as active participants. The organization is co-chaired by DoS/AVC, and the nongovernmental organization, the Nuclear Threat Initiative. Additional information about the International Partnership for Nuclear Disarmament Verification is included in Section 3.4.3.

³⁰ Established in 2015, the Quad is a collaboration between nuclear and non-nuclear weapon states (United States, United Kingdom, Norway, and Sweden) to work on nuclear dismantlement approaches.

development funding is the order of $10 to 15 million annually (NPAC, communication to committee, November 18, 2020). The office represents DOE on matters concerning the New START arms control treaty and Comprehensive Nuclear-Test-Ban Treaty and is involved in policy development and negotiation support for potential future initiatives as well as implementation support and compliance analysis for current U.S. treaty commitments.

1.5.5 Department of Defense

DoD is a key player in setting priorities regarding MDV activities’ implementation, evaluation, and conclusions. DoD also evaluates and develops critical defense technologies that contribute to the MDV mission. Operationally, DoD elements contribute to R&D and execute monitoring and inspection missions in service of agreements, providing literal “boots on the ground” in cases such as the New START arms control treaty. The Office of the Secretary of Defense and the Joint Staff play important roles, through interagency coordination, in setting verification and compliance policies, which affect MDV requirements and limits in the context of negotiating and implementing international agreements.

Defense Threat Reduction Agency

DTRA plays a role in the MDV mission space in terms of both RDT&E and operations. The Research and Development Directorate funds RDT&E to detect, characterize, and defeat nuclear threats, while the On-Site Inspection and Building Capacity Directorate (DTRA/OB) is responsible for conducting all aspects of inspections in current arms control treaties.

DTRA’s overall focus has shifted in recent years from countering terrorism to strategic nuclear deterrence and peer/near-peer competition. As a result, DTRA’s MDV R&D has been refocused to support the Combatant Commanders by providing capabilities³¹ to “find, fix, and defeat” weapons of mass destruction³² in the Combatant Commanders’ respective areas of operation; DTRA’s Research and Development Directorate stressed to the committee that DTRA is focused on counterproliferation, not nonproliferation. This directorate also develops capabilities to support military operations in a post-detonation nuclear environment. Overall, DTRA’s Research and Development Directorate allocates approximately $25 million annually for these nuclear detection R&D efforts (DTRA Research and Development Directorate, briefing to committee, August 27, 2020).

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³¹ These technologies are typically developed to TRL 6 by DTRA and then transitioned to operational users such as the Services or Combatant Commands. An example of this is the development of a radiation detector to mount on Striker vehicles (Nesaw, 2019).

³² DTRA conducts significant RDT&E on countering chemical and biological weapons as well as nuclear weapons.

This directorate’s MDV efforts also focus on nuclear explosion monitoring, and it allocates approximately $12 million annually to this mission (DTRA Research and Development Directorate, briefing to committee, August 27, 2020). In addition to a nuclear explosion monitoring R&D portfolio, the Research and Development Directorate is also responsible for the operation and improvement of the U.S. portion of the International Monitoring System to support compliance with the Comprehensive Nuclear-Test-Ban Treaty. This responsibility includes system performance monitoring and modeling, and RDT&E to develop improved seismic and infrasound sensors and models, laboratory standards, field detection, and next-generation systems.

DTRA also plays an operational role in the MDV mission space. DTRA/OB operates all aspects of monitoring for the New START arms control treaty including training inspectors, maintaining the data exchanges, escorting the Russian inspectors in the United States, and conducting the on-site inspections in Russia. It also conducts on-site inspections in Russia for the Plutonium Production Reactor Agreement and provided technical inspectors and other support for the Open Skies Treaty in partnership with the Air Force before U.S. withdrawal from the treaty in November 2020.³³

Air Force Technical Applications Center

The Air Force has been tasked with detecting nuclear explosions anywhere in the world (underground, at sea, in the atmosphere, and in space) since 1947 for the United States. The mission requirements are specified by national security directives and framed by nuclear treaties such as the 1963 Limited Test Ban Treaty, 1970 Nuclear Non-Proliferation Treaty, 1974 Threshold Test Ban Treaty, 1976 Peaceful Nuclear Explosion Treaty, and the 1996 Comprehensive Nuclear-Test-Ban Treaty.

AFTAC operates the U.S. Atomic Energy Detection System, a network of satellite, hydroacoustic, and seismic sensors, in order to detect nuclear explosion in the atmosphere/space, underwater, or underground. The system also uses ground-based samplers and WC-135 and other aircraft to collect gaseous and particulate samples from suspected or confirmed nuclear detonations. The AFTAC operations center is active 24 hours a day, with rapid alert response. Alert operations include integration of real-time data with post-event atmospheric transport computation, mission planning, airborne collection, synthesis, and final reporting. AFTAC is also a member of the IAEA network of analytical laboratories and analyzes material samples for the IAEA.

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³³ The United States withdrew from the Open Skies Treaty on November 22, 2020, six months after announcing its intention to do so (Brown, 2020).

AFTAC is primarily an operational organization with limited R&D capabilities but is now supporting a small R&D program generally focused on high-TRL development. AFTAC relies on interagency and national laboratory partners for basic and applied research to support its mission. AFTAC’s R&D requirements are communicated to the interagency, industry, and academic partners via an R&D roadmap with a long-term (20-year) outlook.

Air Force Research Laboratory

The Air Force Research Laboratory operates a small R&D program (approximately $2 million annually) in support of AFTAC needs in seismic, infrasound, hydroacoustic, and radionuclide monitoring, primarily at TRL 1 through TRL 3 (Air Force Research Laboratory, communication to committee, January 19, 2021).³⁴ The R&D program provides support to universities and contracting companies through annual proposal calls. The budget level is greatly diminished from prior funding levels in predecessor DoD programs that have sequentially been run out of the Defense Advanced Research Projects Agency, Air Force Office of Scientific Research, and the Defense Special Weapons Agency/DTRA.³⁵

1.5.6 Intelligence Community

The IC plays a significant role in both the R&D and operations components of the MDV mission space. The committee will assess this role in more detail in the final report.

Office of the Director of National Intelligence National Counterproliferation Center

The National Counterproliferation Center was established in 2005 to serve as a focal point in the IC for intelligence on the proliferation of nuclear weapons and fissile material. Its stated vision is to “lead the Intelligence Community and interagency to prevent the proliferation of weapons of mass destruction, their delivery systems, related technologies and expertise” (ODNI, 2021). The National Counterproliferation Center has a clear role as the counter and nonproliferation focal point within the IC, while also collaborating closely with counterparts in NNSA, DoD, DoS, and the NSC. The center also conducts a limited amount of MDV R&D through its Research, Development, and Integration Fund.

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³⁴ This is done in coordination with DNN R&D support.

³⁵ The Defense Special Weapons Agency was absorbed into DTRA in 1998.

1.5.7 Department of Homeland Security

The DHS Countering Weapons of Mass Destruction Office³⁶ plays a role in the nuclear detection mission, in particular through the Global Nuclear Detection Architecture, a system for detecting and characterizing nuclear and other radioactive materials out of regulatory control (DHS, 2014). The SAFE Port Act of 2006 charged DHS³⁷ with coordinating the development of the Global Nuclear Detection Architecture and implementing its domestic component. DHS works with other federal agencies including DOE, DoD, the Office of the Director of National Intelligence, DoS, the Department of Justice, and the Nuclear Regulatory Commission to detect nuclear smuggling. The Global Nuclear Detection Architecture established multiple modes of detection, including the installation of radiation portal monitors at ports of entry. In addition, U.S. Coast Guard and Customs and Border Protection personnel are equipped with portable radiation detectors and trained in their operation.

The DHS Countering Weapons of Mass Destruction Office also conducts RDT&E to improve nuclear detection capabilities. Approximately $16 million annually is spent on R&D (TRL 1 through TRL 5) in radiological/nuclear detection and data analytics, with another $25 to 35 million spent on detector development (TRL 6 to TRL 7) (DHS, 2020).

1.5.8 International Organizations

Where the United States is a party to a multinational agreement, the responsibility for inspection is delegated to an international organization agreed to in each specific treaty. The international organization receives financial support and/or in-kind contributions from the United States and other treaty participants. Besides financial support, the United States strives to ensure that its citizens are well represented in the ranks of the organization as international civil servants.

International Atomic Energy Agency

The IAEA is responsible for verifying states’ compliance with the NPT by confirming that nuclear activities in non-nuclear-weapon states are exclusively peaceful through, among other things, implementation of Comprehensive

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³⁶ The Countering Weapons of Mass Destruction Office subsumed the Domestic Nuclear Detection Office in 2017. While the DHS Countering Weapons of Mass Destruction Office is part of the broader MDV enterprise, the office does not exercise a significant role in fuel cycle monitoring, nuclear test monitoring, or arms control monitoring, the technical areas that the committee focused on in this interim report. Its focus in the MDV sphere is on detecting and countering illicit transfer of nuclear material to the United States, rather than proliferation monitoring and treaty compliance. As such, the committee did not focus on this office in this report.

³⁷ Through the Domestic Nuclear Detection Office at that time.

Safeguards Agreements. As other needs arise, the IAEA has been tasked by its member states to undertake additional activities, such as being responsible for verification of the JCPOA. Through a series of bilateral agreements with member states, the IAEA verifies the completeness and correctness of a member state’s safeguards declaration by deploying monitoring equipment, conducting on-site inspections, and producing an annual country report. The IAEA also maintains laboratories in Vienna and Seibersdorf, Austria that support their global safeguards efforts. An international network of analytical laboratories further augment the IAEA’s capabilities (IAEA, 2012).

The IAEA primarily outsources R&D to member state support programs so that its internal resources can be used to implement global safeguards inspections and verification efforts. It has neither the budget nor the human resources to support a large R&D program. The United States has historically been the largest provider of R&D support and resources to IAEA safeguards through the USSP.

Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization

The CTBTO was established to facilitate entry-into-force of the Comprehensive Nuclear-Test-Ban Treaty, deploy a global monitoring system, and prepare to conduct on-site inspections as detailed in the treaty once the treaty enters into force.

The monitoring regime established by the CTBTO includes the International Monitoring System, a world-wide network of monitoring stations and laboratories around the world,³⁸ and the International Data Centre, which processes and analyzes data collected at the monitoring stations. At the time of entry-into-force,³⁹ an on-site inspection capability can be deployed by the CTBTO at the request of a member state. Current U.S. policy states that while the United States will not seek to ratify the Comprehensive Nuclear-Test-Ban Treaty, it will continue to support the CTBTO, the International Monitoring System, and the International Data Centre prior to treaty entry-into-force (DoD, 2018). All data from the International Monitoring System are made available to any member state that requests it. For the United States, AFTAC, which serves as the U.S. National Data Center, receives the data.

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³⁸ 302 International Monitoring System monitoring stations and laboratories had been certified as of November 2020. See CTBTO (2020) for more information on certified and planned future monitoring stations and laboratories.

³⁹ To enter into force, the Comprehensive Nuclear-Test-Ban Treaty must be signed by India, Pakistan, and North Korea, and be ratified by China, Egypt, Iran, Israel, and the United States.

1.5.9 Nongovernmental Organizations, Academic Institutions, and Professional Societies

Several nongovernmental organizations, academic institutions, and professional societies also support the MDV mission. Nongovernmental organizations and academic institutions advise the government and help inform the general public on MDV issues. The amount of open-source MDV data available to such organizations has grown significantly, enabling them to conduct MDV analyses that can complement government efforts.⁴⁰

Professional societies such as the Institute of Nuclear Material Management and the European Safeguards Research and Development Association serve as venues for information-sharing, international cooperation to promote the development of MDV technical expertise, and the development of relevant standards.

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⁴⁰ See NVCITF (2017) for more information on the role that nongovernmental organizations play in nuclear monitoring and verification.

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