Funny, the Smithsonian Magazine had an article about a similar problem: ground squirrels were burrowing past the fences of a nuclear weapons storage facility and setting off the motion detectors (http://blogs.smithsonianmag.com/science/2013/08/how-one-nuclear-missile-base-is-battling-ground-squirrels/).
I would have thought that, with a squirrel problem on one hand, and a ready supply of nuclear weapons on the other, the obvious solution would present itself.
