Not really, design the motor to work on both frequencies, and install an appropriate sized
or sprocket pulley to get the proper RPMs to the load.
Hi-tech electronics are easy to, just use a crystal based oscliiator, instead of referencing to the power line.

What seems silly to me though, is why they never stepped the shutdown/inspection/possible maintenance
of the plants, unless they are in dire need
of inspection/repairs. In that case, why were
they left to get in a position where the only thing to do would be a shutdown.