There is no green light to the project, the EPA had simply shut down the projects ability to go through the permit project and the recent announcement means (as far as I know) that the project can proceed to the permitting stage.
Could the project be done with 0 risk to the environment? In theory yes. Now will the project be profitable with those level of safeguards in place? I'm betting no.
So that leaves you with just enough safe guards to get the project permitted, but not enough for it to be truly safety.
I work in industrial safety. I can guarantee that risk mitigation is ultimately accepting that you've spent as much as you are willing to mitigate risks but you have not eliminated all of them and that you are accepting a certain number of employees will get injured and killed and a certain level of environmental damage will occur and there is a cost benefit analysis and acceptable risks. They never couch those calculations in those terms, but I can assure you that when the point is reached where an additional level of protection is costing billions, then some risks will be accepted.
