Weapons-grade plutonium and highly enriched uranium (HEU) are the critical ingredients for making a nuclear weapon. With the end of the Cold War, hundreds of tons of these materials were determined to be surplus to U.S. and Russian defense needs. Denying access to plutonium and HEU is the best way to prevent nuclear proliferation among rogue states and terrorist organizations.
The most certain method to prevent these materials from falling into the wrong hands is to dispose of them. While disposing of HEU involves a relatively simple downblending process with depleted or natural uranium, disposing of plutonium is more complicated.
The U.S.-Russia Plutonium Management and Disposition Agreement (PMDA), which entered into force on July 13, 2011, commits each country to dispose of at least 34 metric tons of weapon-grade plutonium withdrawn from their respective nuclear weapon programs. The U.S. remains firmly committed to its PDMA obligation to dispose of excess weapons plutonium.
U.S. Plutonium Disposition
The current U.S. plan to dispose of 34 metric tons of weapon-grade plutonium is to fabricate it into MOX fuel and irradiate it in existing light water reactors. This approach requires construction of new facilities including the MOX Fuel Fabrication Facility and Waste Solidification Building at the Savannah River Site. Unanticipated cost increases for the MOX project and plutonium disposition program have prompted a need for NNSA to determine if there are options to complete the mission more efficiently.
Russian Plutonium Disposition
Under the PMDA, Russia plans to dispose of 34 metric tons of weapon-grade plutonium by fabricating it into MOX fuel and irradiating it in fast reactors operating under certain nonproliferation conditions. Irradiation in fast reactors is a technically credible approach for Russian plutonium disposition that is consistent with Russia's national energy strategy, relying upon the use of both existing and planned Russian fast reactors.