I Have a Very Basic Question

So, I've read three or four major media articles about the Lightworker's desperate legacy groping, cynical fundraising scam new climate policy initiative (like this one) and, curiously, nowhere in any of the reportage is there mention of the underlying law which gives the EPA authority to promulgate this new, sweeping rule.  I thought regulators could only regulate under the authority of a specific piece of legislation.  Absent a change in law, I don't see how the EPA can pursue a major escalation of regulation.  Am I missing something here?

Now, I know that the law doesn't matter to this crowd, but seriously, this is major stuff.  When we are talking a potential $50 billion hit to the economy, shouldn't we pay attention to this stuff?