"As of 2008, US$9 billion had been spent on the project which has made Yucca Mountain one of the most studied pieces of geology in the world.
...
The U.S. Department of Energy was to begin accepting spent fuel at the Yucca Mountain repository by January 31, 1998. However, 10 years after this deadline, the repository at Yucca Mountain is still over a decade away from being opened,..

Following the 2006 mid-term Congressional elections, Nevada Senator Harry Reid, a long time opponent of the repository, became the Senate Majority Leader, putting him in a position to greatly affect the future of the project. Reid has said that he would continue to work to block completion of the project, and is quoted as having said: "Yucca Mountain is dead. It'll never happen."
http://en.wikipedia.org/wiki/Yucca_Mountain

Of course, Reid also said the Iraq war was lost, so one shouldn't put much weight in his proclamations. Though one could expect he will try drive up the cost as high as he is able.