Roland Piquepaille writes "New Scientist reports in this pretty alarming article that there is a 50-50 chance of a major radiation or chemical accident during the cleanup of the dirtiest nuclear site in the U.S. There are indeed lots of things to clean at the Hanford complex in Washington state: 67 tons of plutonium and 190 million liters of liquid radioactive waste stored in underground tanks. A third of them, dating from the Cold War, have already leaked 4 million liters in the environment, contaminating the groundwater and a river. Meanwhile, officials at the DOE, who'll spend $50 billion between now and 2035 on this cleanup, seem less worried than the different specialists interviewed by New Scientist. Please read this overview for selected quotes from the article and from the Hanford site. You'll also find a slide from the DOE showing the timeframe for the cleanup."