Soviet-Era Plutonium Reactor Shut Down

Russia said Monday that it had closed a weapons-grade plutonium reactor as part of a deal with the United States to reduce the risk of proliferation from Cold War-era nuclear bomb plants.

The reactor, at a secret Siberian plant founded by Soviet leader Josef Stalin, was turned off Sunday, 45 years after it started producing plutonium for the Soviet weapons program.

"The industrial reactor ADE-4 was finally stopped on Sunday at 11 a.m. That is the final closure of the reactor," said a spokesman for the Siberian Chemical Combine, in the city of Seversk, formerly known as Tomsk-7.

After the end of the Cold War, weapons-grade plutonium was no longer needed for Russia's nuclear weapons program.

But the reactors at the plant were kept running to provide heat and electricity for the local community, and the U.S. Department of Energy has estimated that the plant produced enough plutonium for several nuclear bombs per week.

The unwanted plutonium was stored at the plant, prompting environmental groups to raise questions about its security. Russia says its nuclear plants are properly guarded.

Reuters, AP