The Hanford Site is a decommissioned nuclear production complex on the Columbia River in south-central Washington operated by the United States government. Established in 1943 as part of the Manhattan Project, it was home to the B-Reactor, the first full-scale plutonium production reactor in the world.[1] 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 was expanded to include nine nuclear reactors and five massive plutonium processing complexes, which produced plutonium for most of the 60,000 weapons in the U.S. nuclear arsenal.
The weapons production reactors were decommissioned at the end of the Cold War, but the manufacturing process left behind 53 million U.S. gallons (204,000 m³) of high-level radioactive waste that remains at the site.
Today, Hanford is the most contaminated nuclear site in the United States. In recent years, the federal government has spent about $2 billion annually on the Hanford project. About 11,000 workers are on site to consolidate, clean up, and mitigate waste, contaminated buildings, and contaminated soil Originally scheduled to be complete within thirty years, the cleanup was less than half finished by 2008.
While major releases of radioactive material ended with the reactor shutdown in the 1970s, parts of the Hanford site remain heavily contaminated.
– from wikipedia