HHi
If God would destroy those ruining the earth he would have to destroy all of us. We all pollute the earth by eating meat (animals fed by soja from places where there was rainforest, contributing to pollution more co2 and methan into the atmosphere by the burps of the cows that we breed just to kill them) by overusing earths resources, using cars and airtravel and so on and so on.
I realised that Jws don't really care about trying to live in a way that shows respect to gods creation. Most of them think it doesn't matter how to behave in that regard as Jehovah will change it anyway after armaggeddon. They rather go to field service with their car groups, driving to each house with the car running (at least in the us, in other countries we use our legs in field service).
My opinion about fukushima
It's a huge manmade disaster. Of cause God will not step in in fukushima. Fortunately the earth is designed in a way that she can resolve huge impacts in her ecology. Wounds like that can heal That just needs time. We are talking here about ten- hundred thousands of years (nuclear waste) or even millions of years (climate).
The earth will survive. If humans will be there is another question. Maybe we will end up fossilized like dinosaurs and another species in the future would try not to make the same mistakes than us.
The earth will survive even though humanity wounds her.