A Tour of America's Nuclear History

The federal government is easing security restrictions and allowing thousands of people to visit the site this year. It's part of a move to create more understanding about nuclear power, but also about the severe challenges of storing its waste and cleaning up its messes.

"The U.S. Department of Energy is making Hanford more accessible to the public this year than at any time in the area's notoriously secret history. More than 2,500 people booked tickets for a free, five-hour tour (60 in all) within 24 hours after the DOE made reservations available online. Another 1,000 people will likely visit the historic B Reactor - the heart of the Manhattan Project - on shorter tours available without reservations every Saturday. In October 2008, the B Reactor - with its control room and towering wall of knobs and hoses neatly arranged - was named an official historic landmark.

Paige Knight, founder of Hanford Watch, a citizen watchdog group, said a change in leadership at Hanford about two years ago triggered an effort toward greater transparency. Public tours are part of that. They offered tours in the 1990s, but those ended after 9/11. Tours have steadily increased since 2004 when Hanford offered just four. Last year, 48 took place."