There is more to Yucca Mountain than just the mountain.
About 90 percent of U.S. nuclear power reactors are located in the Eastern states, where there is ample water for cooling and heat transfer. To use Yucca Mountain, spent reactor fuel must be shipped 1,000 to 2,000 miles, either by rail or truck, to Nevada through several other states that may not like having radioactive material traveling through their borders.
To contain the spent fuel rods safely while shipping requires massive casks – some of which may need cooling while in transit.
Now come the questions: How many rods per cask? How many casks per train? Will the trains have speed restrictions? Is there a security problem, such as sabotage? How much will this affect normal train shipping?
At any rate, there are both logistic and political problems that need to be solved before Yucca Mountain can be used as storage for spent reactor fuel. I expect there will be several paranoid committees and sub-committees pondering solutions to the hypothetical problems raised in shipping spent nuclear fuel. And make no mistake, it will cost big bucks.