Nobody paid much attention until we heard it on the radio and someone asked how much shaking the nuke box can withstand.
Contrary to the information released by Tempco the Fukishima reactors were reported to have began melting down before the Tsunami hit and took out the backup Diesel gen sets. I think that most reactor documentation requires the recording of X-ray welds to the plumbing which keeps the whole pile cool i.e static pressure testing. I don't think that the welds are tested for shear forces so even a relatively minor earthquake could prove to be quite disastrous.
On the way home I heard a radio news discussion of the topic of the safety of the local (Lake Anna, I think) nuclear plant. Apparently it was designed to withstand the largest known earthquake in the area, plus "a safety margin." That designed in safety margin quake size was almost, if not the same, as the 5.8 they just suffered. A too close call IMO.
What many people forget is that designed in safety margins are reduced if not downright eliminated by age and lack of proper maintenance. Just because a structure when brand new had a 1.5X (or whatever) designed in safety margin, years of neglect and poor maintenance erodes this until you lose that safety margin and start eating into the actual required strength. "Deferred Maintenance" or whatever the current buzz-words are for not doing proper maintenance can be deadly.