Nine plutonium production reactors operated at the Hanford Site to produce plutonium for America’s nuclear weapons program. The reactors required extensive amounts of water for cooling, and were located along the Columbia River. The first reactor, B Reactor, began operation in 1944. The last of the reactors was shut down in 1988.
B Reactor is being preserved as a museum. The rest of the reactors have been or are being put into a safe storage condition referred to as “cocooning.” All support buildings are demolished; surface contamination and surplus materials are removed throughout the reactor building; a new roof is installed; and the reactor is sealed. The intent is to allow the reactor to sit safely for 75 years or so while radioactivity in the reactor core is reduced through radioactive decay.
Click on any of the reactor areas to see historical and current photos of each of the reactors.