(AP) - Russia closed down a plutonium producing reactor Sunday, a Russian news agency reported, marking a milestone in U.S. nuclear nonproliferation efforts.
The United States and Russia have been working for years on arrangements to close Russia's three remaining weapons-grade plutonium producing reactors.
ITAR-TASS cited a Siberian Chemicals Plant official, Alleges Suglobov, with announcing the closure of the plant in the Siberian town of Seversk. Plant and Russian Federal Atomic Energy Agency officials could not be reached for comment.
Nuclear reactors in Russia have been plagued by a history of glitches that have raised safety concerns. Just weeks before its closure, the reactor was temporarily deactivated due to a power failure. No leaks were detected, however.
A second reactor, also in Seversk, is expected to be shut down in June while a third reactor, in the central Siberian town of Zheleznogorsk, is expected to be shuttered at the end of 2009.
Closing the reactors has been a major U.S. nonproliferation goal. But the plants provide electricity and heat to the nearby towns, and the Russians had been reluctant to shut them down before two new fossil fuel plants are built.
An agreement was reached in March 2003 between the U.S. and Russia in which Washington committed $926 million to help build the fossil fuel plants. One in Seversk is almost completed.
Seversk, formerly known as Tomsk-7, is among 10 cities once at the heart of the Soviet Union's nuclear weapons production complex. The reactors were built in secret in the 1960s in the arms race with the U.S.
The design of the Seversk reactor that closed Sunday was similar to the Chernobyl reactor involved in the 1986 nuclear disaster in Ukraine, lacking concrete containment domes to hold in radiation in case of an accident or major leak.
The U.S. has already closed all 14 of its plutonium reactors.