Trump's executive orders have been in the works for months, but the widely-expected move will still reverberate throughout the industry. The Clean Power Plan was President Obama's big climate rule and represented a key test of the EPA's authority to regulate emissions from the power sector.
Tuesday's order directs the EPA to initiate a review of the Clean Power Plan, governing existing plants, and accompanying regulations for carbon emissions from new sources.
The order also directs each executive department and agency in the federal government to identify regulations, rules, policies, and guidance documents that slow or stop domestic energy production, and launches a 170-day process to develop plans from each agency going forward.
Trump also ordered agencies to stop using Obama-era estimates of the social cost of carbon. Regulations affecting methane leaks at oil and gas production facilities and hydraulic fracturing will all be reviewed, and a moratorium on coal leases on federal lands will be eliminated.
While the coal moratorium can be lifted immediately, the CPP and other finalized Obama-era regulations will undergo formal policy reviews.
Though the White House has made clear it thinks the rules are an overreach, whether its reviews will result in new regulations for the power sector or simply the elimination of old ones remains to be seen.
"It could be revising, improving, updating, or if things are illegal or, again, if they don't conform to the President's priorities," an administration official told reporters this week. "It depends — it runs the gambit. That's what review is for."
If the administration chooses to replace the CPP with a less stringent rule, it could result in a narrower regulatory package that would require only small efficiency improvements to existing coal plants. EPA Administrator Scott Pruitt wrote such an alternative plan in 2014.
If no plan is offered to replace the CPP, the EPA could be at risk for lawsuits claiming that it is not fulfilling its obligation to regulate greenhouse gases, which the agency determined were a public health threat in a 2009 endangerment finding.