Doesn't matter whether it's a nuclear reaction (which it appears to be) or otherwise, what happens when those pipes for the cooling liquid are broken? It doesn't seem like a very self-contained electricity generation system. The actual electricity is generated outside this unit. So, let me ask a different question. Something bad happens to your connections to the "nuclear battery". Control lines and water-cooling cut. Does the reaction just magically stop? Forgive me, I stopped taking physics after my freshman year. Forget for a moment the unlikely acts of terrorists (whether they be evil ferinners and godless heathen or God fearing, tax paying, white folk out to topple the corrupt regime) and think about big-ass storms, seismic events, wildfires or neighbourhood industrial accidents.