I'm no chalk-expert, but I'd question whether anything there is deep/shielded enough to qualify.
Even then, it might be far cheaper to build an "EMP resistant" structure aboveground.
No, but it's the kind of narrative that will help bring an above market price by casting its uniqueness as a feature, rather than the default of being a liability for differing from a plain beige box </realtalk>.
Depends on how close you are to the nearest nuke factory