The planned U.S. nuclear waste dump at Yucca Mountain in Nevada will cost billions more than previously estimated due to a hike in the amount of waste it will have to dispose of and inflation, the Energy Department said. At the same time, Presidential hopeful John McCain proposed building 45 new nuclear plants in the U.S. The Yucca Mountain program, which began in 1983 and is expected to close in 2133, is expected to cost $96.2 billion in 2007 dollars over its 150-year life cycle, up 67 percent from a 2001 estimate of $57.5 billion.