EPA considering rollback of key climate change tools that regulate greenhouse gas emissions: report

SAN FRANCISCO (KGO) -- The Environmental Protection Agency is reportedly considering a major rollback of one of its cornerstone climate change findings - one that has allowed the federal government to limit pollution from greenhouse gases for more than 15 years.

According to The New York Times, the Trump administration has drafted a proposal to rescind the EPA's 2009 "endangerment finding," a scientific determination that greenhouse gas emissions pose a risk to human health and well-being. While ABC News has not independently confirmed the report, climate experts say it would be consistent with the administration's pattern of scaling back environmental protections.

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The 2009 finding, issued during the Obama administration, concluded that carbon dioxide and other greenhouse gases contribute to air pollution that threatens public health. Once the EPA made that finding, it was legally obligated under the Clean Air Act to take action to reduce emissions.

"By trying to unwind that endangerment finding, they're really trying to take a shortcut and get rid of all the climate regulations the EPA's issued over the last 20 years," said Meredith Hankins with the Natural Resources Defense Council.

Environmental law experts say rescinding the rule could allow for the repeal of existing pollution standards, including emissions limits on vehicles and power plants. That could have ripple effects across industries-and across generations.

"This is a five-alarm fire," Hankins warned. "It's this cumulative impact that just keeps piling on."

Despite the administration's reported intentions, some legal scholars are skeptical that such a move would hold up in court, due to a 2007 U.S. Supreme Court decision in Massachusetts v. EPA. The high court found that greenhouse gases qualify as pollutants under the Clean Air Act, paving the way for the endangerment finding in the first place.

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"I think the issue would be whether they can somehow get a court to undermine Massachusetts v. EPA," said UC Berkeley environmental law professor Dan Farber.

Farber acknowledged that over the last several decades, there has been back and forth between presidential administration changes when it comes to climate regulations. If this proposal goes through, it could hypothetically be reversed by another future president, but experts say time is of the essence.

"We're starting to see some serious impacts like flooding, increased storm intensity, major heat waves. And that's only the beginning. So people really need to start thinking hard about how are we going to keep this problem from getting worse, and how are we going to cope with the problems we already have," he said. "Unlike other forms of air pollution, if we have a surge of CO under Trump, that CO is going to be in the atmosphere for up to 200 years, heating the planet."

The New York Times is also reporting that the EPA's draft seeks to repeal tailpipe emission standards, which have pushed automakers to develop more electric vehicles. But Farber believes California's own stringent climate rules would likely remain intact, at least for now.

"The way the federal environmental laws are written, they generally allow states to do more than the federal government is doing. And the only exception to that, where there's a problem, has been emissions from cars. And, and that's all wrapped up in a bunch of other legal issues right now," he said.

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Even if the White House approves the draft proposal, the public would have a chance to weigh in before anything is finalized.

"Every time we try to start again," Farber said, "we're that much deeper in the hole."