As discussed by the inimitable Jonah Goldberg on NRO.
The point that keeps getting obscured is that whatever objections may be raised to Yucca Mountain, 1) it's better than anyplace else we're using now for the same purpose, and 2) we're not likely to find better. To bitch about nuclear waste *and* Yucca Mountain's use for disposal is about as clear-cut an example of the best being the enemy of the good that you're likely to see.
That's assuming that you believe antinukers are motivated by genuine informed concerns. At best this does not account for all of them. Many of the rest simply want to cause the US nuclear power industry to die of constipation, and they figure that this is the way to make it happen.