As the Soviet Union was unraveling and the Cold War was winding down in the early 1990s, negotiators in Washington and Moscow began talking about how best to dispose of the plutonium inside thousands of nuclear warheads the two nations had agreed to dismantle. The cheapest and easiest method was to immobilize the radioactive material by encasing it in molten glass and burying it. But the Russians balked at that, likening it to flushing gold down the toilet. Ultimately, it was decided that the plutonium would be converted into fuel for nuclear power plants. In September 2000, the U.S. and Russia signed an agreement under which each side would turn 34 tons of weapons-grade plutonium into mixed-oxide fuel, or MOX, that could be combined with uranium for use in commercial reactors.
In the U.S., that huge task would take place at an aging plutonium factory in South Carolina called the Savannah River Site. From the 1950s to the 1980s, the 310-square-mile facility had churned out about 36 tons of weapons-grade plutonium for nuclear warheads. Now, the plant would turn those same warheads into fuel rods. The Department of Energy initially estimated it would cost about $1 billion to convert the plant. Construction began in August 2007, with an expected completion date of 2016.