Plutonium is not a fun word to speak, hear, or write. Used to depict an actinide metal we've known about for some time, it has become synonymous with human-caused destruction on a hard-to-comprehend ...

Multi-day fast-spectrum reactor experiments at the U.S. Department of Energy’s National Criticality Experiments Research Center generate modern benchmark data. The data supports Oklo’s ...

This article is part of “The New Nuclear Age,” a special report on a $1.5-trillion effort to remake the American nuclear arsenal. In early nuclear bombs, like the ones the U.S. dropped on Japan in ...

In September, the city council of Westminster, Colorado voted not to fund a pedestrian bridge and underpass at the Rocky Flats site due to concerns about residual soil contamination from plutonium and ...