There was a far greater ecological disaster in the former Soviet Union than in the United States. I don't think the comparison is fair since Soviet chemical and gas companies didn't do quite the level of investment in third world countries as American companies did. I think one needs to factor in things like Bhopal, Nigeria delta, etc. when comparing to the Soviet Union. We just shifted the dirty work, literally, to other countries.
The problem as I see it comes from trading with countries without high levels of worker safety standards and environmental standards. Also from not accounting for negative externalities. A tax on carbon would be useful. Things like that.
A man said many years ago that the love of money was the source of all evil and this, I think, is the crux with the problem of capitalism. Money is not a great motivator. Newton did not invent calculus to make billions. Leonardo would not have painted better if he had been paid more. I don't the answers to the problem but I do believe there is a huge problem with capitalism and, more specifically, corporatism.
Adam Smith opposed corporations because the externalities weren't accounted for (to use modern parlance). I agree with him on this. There are lots of examples of corporations acting in a brutally authoritarian way and the comment by nazgulnarsil seems to imply that by reading history one comes away with a view opposite to:
" fortune 500 company a "brutal authority" "
Again, I don't know the solution but there is a problem and plenty of examples of Fortune 500 companies acting with brutal authority.
EDIT: I'm not implying in any way that the Soviet Union was a model or that it ought to be emulated. I don't suggest communism as practiced by the Warsaw Pact nations was better than capitalism.