December 15, 2006

DOE project converts weapons-grade uranium to fuel for Browns Ferry

James M. Hylko

During and following the Cold War, it was assumed that the Soviet Union had produced weapons-grade, highly enriched uranium (HEU) from 1950 through 1988 for defense purposes. With the collapse of the USSR in the early 1990s, there was concern that this HEU—containing between 20% and 90% uranium-235 (U-235) and plutonium—could be stolen from weapons sites and end up in the wrong hands.

 

For perspective, the HEU in U.S. and Russian weapons and other military stockpiles totaled approximately 2,000 metric tons (MT), equivalent to approximately 12 times annual world mining production. Stockpiles of weapons-grade plutonium were reported to be 260 MT, which, if used as mixed oxide fuel (MOX) in conventional commercial nuclear reactors, would be equivalent to over one year's worth of world production.

Beginning in 1987, the U.S. and countries of the former Soviet Union signed a series of disarmament treaties to reduce nuclear arsenals by 80%. In 1993 this collaborative effort resulted in the U.S. agreeing to purchase low-enriched uranium (LEU) from Russia that had been made from HEU extracted from dismantled Russian nuclear weapons over a 20-year period. The Megatons to Megawatts (MtM) program called for HEU to be downblended (diluted) with depleted uranium (mostly U-238), natural uranium (0.7% U-235), or partially enriched uranium to produce LEU, which is typically less than 5% U-235. The LEU then would be used as a major source of fuel for commercial nuclear power reactors.

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