I don't see why this is such a big deal outside of the wacky environmentalists. Nuclear power is a viable and powerful way to power spacecraft, especially if we want to do more than robotic space exploration.
If this is a solved problem, then my fears are unfounded. Let me know.
In that context, the remote possibility that a rocket might accidentally fail in a way that somehow managed to crack open its little reactor, spilling some radioactive material in a way that somehow harms anything whatsoever, would seem quite trivial. I'd be more worried about airliners crashing into me on the freeway if I were you.
In other words, I'll bet you five bucks that nothing radioactive will drop onto your house the next time they launch a satellite with a nuclear reactor onboard.
... Which are potentially even safer, because the fuel is not terribly radioactive until it has actually been in the reactor. Ship it up in parts, assemble when safely in orbit.
And I remember reading that we are a little short on the right fuel for those right now, since it has not been manufactured in years.