A Short History of Hanford

Nine nuclear reactors and four reprocessing plants at Hanford produced nearly two-thirds of the plutonium used in the United States for government purposes . These site operations also created large volumes of radioactive and chemical waste. Some contaminants were released into the environment, exposing people who lived downwind and downstream. Other contaminants were stored. The last reactor was shut down in 1987, and the last reprocessing plant closed in 1990. Most of the human-made radioactivity and about half of the chemicals remaining onsite are kept in underground tanks and surface facilities. The rest exists in the soil, groundwater, and burial grounds. Hanford contains about 40% of all the radioactivity that exists across the nuclear weapons complex. Today, environmental restoration activities are under way.