Demilitarizing weapons-grade plutonium

Abstract

The news story about stockpiled weapons plutonium (Physics Today, July 2014, page 24) was limited to federal budget expenses for demilitarization. Another part of the equation is that direct income from sales as fuel would help offset expenditures for conversion, not to mention the enormous indirect value for nuclear arms reduction and nonproliferation.The 20-year joint US–Russia Megatons to Megawatts program for demilitarizing 500 tons of weapons-grade uranium proved at its completion in 2013 to be an on-schedule winner—in mutual arms control, economics, and nonproliferation. About 20 000 Soviet nuclear warheads were effectively converted to civilian reactor fuel that supplied half of US nuclear power plants and now produces as much as 10% of US electricity. The program readily paid for its federal budget outlays, and it reduced national and international nuclear risk—a swords-into-plowshares paradigm.The Russian Federation is now on track to convert 34 tons of weapons plutonium into peacetime energy, as long as the US carries out a comparable inventory reduction according to a 2001 agreement between the two countries. Altogether, that would correspond to irreversible reduction of 10 000 or so nuclear weapons from the US arsenal.On the wholesale market, 34 tons of weapons-grade plutonium might eventually fetch as much as $3 billion, equivalent to $30 billion in taxable retail sales. Even if costs for the 60%-completed South Carolina mixed-oxide (MOX) fuel facility inflate, multiple national and international benefits of plutonium conversion would outweigh the extra costs.Moreover, the irrevocable demilitarization of weapons plutonium would reduce the risk of international proliferation and nuclear terrorism. Whether MOX is reactor grade or weapons grade, its burnup—using the processed fuel to generate electricity—adds physical, chemical, radiological, and isotopic barriers that reduce accessibility and utility. European nations have gained relevant experience in MOX burnup for both reactor- and weapons-grade plutonium. Once converted to MOX, the reactor fuel is no longer usable in nuclear weapons, a technical detail never contradicted by specific nuclear-test technical data.The MOX weapons-conversion program would help the US comply with its international obligations toward worldwide reciprocal nuclear disarmament under article VI of the Nuclear Non-Proliferation Treaty. Such a move would present a commendable example for the other weapon states—the UK, China, and France.© 2015 American Institute of Physics.