Ending the Production of Fissile Material
for Nuclear Weapons:
Background Information and Key Questions

Prepared by the
Institute for Science and International Security (ISIS)
Washington, D.C.

David Albright
Lauren Barbour
Corey Gay
Todd Lowery

Prepared for the Fissile Material Information Workshop
Co-sponsored by the Institute for Science and International Security
and the Permanent Mission of Canada to the United Nations, Geneva
25-26 January 1999, Geneva, Switzerland

Table of Contents

Introduction

Acknowledgments

About the Institute for Science and International Security (ISIS)

Key Terms

I. Key Nuclear Explosive Materials
What Are Isotopes?
Fissionable Isotopes
Uranium 235
Uranium 233
Plutonium isotopes
Neptunium 237
Americium
Other isotopes
Tritium

II. Production of Plutonium and Highly Enriched Uranium
Plutonium Production
Irradiation of Reactor Fuel
Spent Fuel Reprocessing
HEU Production
Table II.1: Plutonium half-lives, and weapon-grade and reactor-grade isotopic concentrations at given fuel discharges

Appendix
Reactors for Electricity Generation

III. Nuclear Fuel Cycles
Civil Nuclear Fuel Cycles
Front end of the Fuel Cycle
Back end of the Fuel Cycle
Military Plutonium Nuclear Fuel Cycles
Figure III.1: "Once-Through" Fuel Cycle for Low-Enriched Uranium Reactors
Figure III.2: "Closed" Fuel Cycle
Figure III.3: N Reactor Nuclear Fuel Cycle

Appendix
Figure III.A.1: Savannah River Production Reactor Fuel Cycle

IV. Scope of the Treaty
Basic Obligations and Definitions
Definition of Fissile Material
Definition of Production of Fissile Material
Civil Activities
Military Activities
Selected Existing Proposals
U.S. Proposal
Australian Proposal
Pakistani Proposal
Egyptian Proposal

V. Treaty Verification Goals and Options
Key Verification Questions to be Resolved in Negotiations
Materials Subject to Verification
Facilities Subject to Verification
Implementation and Termination of Verification Measures
Definition of a Violation
Declarations or Transparency Measures
Types of Inspections
National Technical Means
Transfers of Stocks to Other States
Non-proscribed Military Activities
Verification Agency
Existing Verification Systems
Existing Civil Nuclear Inspection Regimes
National Technical Means
Non-routine Inspections

VI. World Inventories of Plutonium and Highly Enriched Uranium
Table VI.1: Estimated Global Fissile Material Inventories, end of 1997 central estimates in tonnes
Table VI.2: Production and Status of Military Stocks of Fissile Material, end of 1997 central estimates in tonnes
Table VI.3: Unirradiated Civil Plutonium, 1996 declarations in tonnes
Table VI.4: Fissile Material Declared Excess as of July 1997, in tonnes
Table VI.5: U.S., Russian Military Stocks of Highly Enriched Uranium, in tonnes
Figure VI.6: World-Wide Plutonium and Weapon-Grade Uranium Estimates, end of 1997 central estimates in tonnes
Figure VI.7: World-Wide Inventory of Plutonium, end of 1997 central estimates in tonnes
Figure VI.8: Unirradiated Civil Plutonium Holdings in Country, 1996 declaration in tonnes
Figure VI.9: Military Stocks of Plutonium in Nuclear Weapon States, De Facto Nuclear Weapon States, and North Korea, end of 1997 central estimates in tonnes
Figure VI.10: World-Wide Inventory of Weapon-Grade Uranium Equivalent, end of 1997 central estimates in tonnes
Figure VI.11: Weapon-Grade Uranium Equivalent in Nuclear Weapon States and De Facto Nuclear Weapon States, end of 1997 central estimates in tonnes

VII. Reducing Stockpiles of Military Fissile Material
Providing More Information
Reducing Military Fissile Material Stocks
Declaring and Placing Excess Materials Under International Verification
Disposition of Excess Fissile Material