The key is to nationalize the harm; People are blind to the pollution when government does it, and if they do notice, you can blame the opposition, or just resign. Nobody who really screws up gets held accountable in government unless it helps someone get elected, so be sure to have dirt on enough people.

Just playing devil's advocate but are you being facetious? Because I'm pretty sure the execs at Dupont have not been executed, and there's not many companies with a bigger environmental impact than Dupont at least with chemicals in our drinking water, other than oil companies of course but you could argue those are secondary effects since most of the damage comes from a resource they sell and use.