What would be the social consequences if a nuclear power plant exploded?

First and foremost, it is impossible for a nuclear power plant to explode. i.e. to go nuclear, because it is impossible for it to stay in prompt critical geometry long enough to consume the fuel for a runaway reaction to occur. Period. Not possible.

Even if a terrorist organization infiltrated the facility and blew it up, that would be a chemical explosion, not a nuclear explosion. Yes, there would be release of radioactive materials to the environment, but it would not be a nuclear detonation as from a nuclear bomb.

Get your heads straight around that. Its just not possible. The geometry is all wrong.