Trump plan to give start-ups plutonium harvested from Cold Warera nuclear weapons is risky, experts say

The plan to supply plutonium from dismantled Cold War nuclear weapons to private energy companies is criticized for weak economic logic and potential national security risk. The United States has no operational nuclear reactors designed to use plutonium-derived fuel, while existing plants use a uranium isotope mixture. Typically about 5% of the fuel is uranium-235, which can be used for nuclear weapons, and the rest is uranium-238, which cannot sustain fission alone. This fuel composition makes weaponization extremely difficult if material is diverted. Plutonium is not found naturally and is produced in reactors when uranium-238 absorbs neutrons and decays into plutonium, which can be blended with uranium for mixed oxide fuel in specific reactor types.

"The Trump administration's plan to offer plutonium from dismantled Cold War-era nuclear weapons to private energy companies is drawing criticism from experts who say it makes little economic sense and presents a national security threat. There are currently no operational nuclear reactors in the country that are built to use plutonium-derived fuel. Instead nuclear power plants in the U.S. are powered by a mixture of two uranium isotopes."

"A small portion, usually around 5 percent, of that fuel is uranium 235, which can also be used to make nuclear weapons. The majority is uranium 238, which cannot sustain a nuclear fission reaction on its own. Because of that balance, if some of this fuel were to fall into the wrong hands, it would be enormously difficult to weaponize, says Scott Roecker, vice president of nuclear materials safety at the Nuclear Threat Initiative, a nonprofit dedicated to preventing nuclear catastrophe."

"The most difficult step in getting a nuclear weapon is having enough of that material, he explains. The U.S. government has spent probably billions of dollars over the last several decades to remove highly-enriched uranium and separated plutonium from countries that don't need it. Plutonium, meanwhile, does not occur in nature and is a by-product of the reactions that take place inside nuclear reactors."

"As uranium 238 is bombarded with neutrons inside the reactor, the molecules absorb some of these particles and become the heavier uranium 239, which eventually decays into extremely radioactive plutonium. That plutonium can be mixed back with uranium to be used as fuel in specific nuclear reactors called mixed oxide reactors. The U.S. abandoned mixed oxide reactors in the 1970s becau"

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