>>516010899
Bunker busters can pierce the concrete reactor containment areas. If safety mechanisms are damaged and there's too great a risk for personnel in the area or they're killed you could potentially have a runaway reactor as was the case in Chornobyl although that was due to reckless testing procedure under unfavorable circumstances, incompetence in the heat of the moment and shitty reactor design.
The current Chornobyl situation's different in that Russia wants to incorporate its territorial gains so there's no incentive to devastate the containment facility, not necessarily the case in a broader conflict where say you might attack France's nuclear power infrastructure behind enemy lines so the example doesn't really apply in this instance. As for a Naval vessel if it sinks the radioactive material would mostly be contained at the bottom of the sea and space is already filled with radiation so it's no biggie as opposed to the trade off of fuel requirements otherwise needed for sustained deployment in any other type of power plant.