Closed city of Krasnoyarsk-45 / Zelenogorsk

The closed city of Krasnoyarsk-45, currently Zelenogorsk, was established in the late 1950s – early 1960s to produce enriched uranium for the Soviet nuclear weapons program.

The construction of a gaseous diffusion plant probably began in the early 1960s and the plant started to produce enriched uranium in 1964. (In 1964, the U.S. intelligence community predicted that the plant would reach its design capacity in 1967.) In parallel, the construction of a large fossil fuel and hydro-electric plant (GRES-2) began to provide the enrichment complex and the town with heat and electricity.

In the 1960s, the Soviet Union began to replace the gaseous diffusion machines with centrifuges. The last gaseous diffusion cascade in Krasnoyarsk-45 was shut down in 1990.

Currently, the Electrochemical Plant in Krasnoyarsk-45 accounts for 29 percent of Russia's enrichment capacity. In addition to uranium, the complex also separates isotopes of tungsten, molybdenum, krypton, xenon, germanium, iron, sulfur, oxygen, and carbon. Since 1997, the facility has been involved in down-blending HEU from dismantled weapons under the U.S.-Russian HEU agreement.