The Hanford site is a mostly decommissioned nuclear production complex operated by the federal government in south-central Washington.
Established in 1943 as part of the Manhattan Project, Hanford home to the B Reactor, the first full-scale plutonium production reactor in the world. Plutonium manufactured at the site was used in the first nuclear bomb, tested at the Trinity site, and in Fat Man, the bomb detonated over Nagasaki, Japan.
During the Cold War, the project expanded to include nine nuclear reactors and five large plutonium processing complexes, which produced plutonium for most of the more than 60,000 weapons built for the U.S. nuclear arsenal. Nuclear technology developed rapidly during this period, and Hanford scientists produced major technological achievements. Many early safety procedures and waste disposal practices were inadequate, and government documents have confirmed that Hanford’s operations released significant amounts of radioactive materials.
Hanford is currently the most contaminated nuclear site in the country and is the focus of the nation’s largest environmental cleanup. Besides the cleanup project, Hanford also hosts a commercial nuclear power plant, and various centers for scientific research and development.
On November 10, 2015, it was designated as part of the Manhattan Project National Historical Park alongside other sites in Oak Ridge and Los Alamos.