Last year, the Obama administration canceled plans to make Yucca Mountain the permanent storage site for the nation's nuclear waste. The half-built site is seen here in a file photo from 2006.
Above-ground casks at the Diablo Canyon nuclear power plant store some of the utility's nuclear fuel. Because of a lack of a central repository, nuclear waste is piling up at individual reactor sites across the United States.
A model of a storage container illustrates how used nuclear fuel will be placed in cast-iron inserts, then encapsulated in large copper cannisters and buried more than 1,500 feet down in the Swedish bedrock.