Legal experts say it's a marked departure from the agency’s historic purpose to protect human health and the environment. “It's an all out assault on climate regulation and environmental and public health protections,” says Michael Burger, director of the Sabin Center for Climate Change Law at Columbia University.

In a barrage of pronouncements Wednesday, the Trump administration said it would repeal dozens of the nation’s most significant environmental regulations. EPA Administrator Lee Zeldin described it as "the greatest day of deregulation our nation has seen.

Three former Environmental Protection Agency leaders sounded an alarm Friday, saying rollbacks proposed by EPA Administrator Lee Zeldin endanger the lives of millions of Americans and abandon the agency's dual mission to protect the environment and human health.

On a day featuring a blitz of environmental regulatory actions, the EPA on Wednesday announced two particularly sweeping climate change moves. Why it matters: The moves reveal the administration's strategy to "revisit" or "revise" both the social cost of carbon as well as the 16-year-old endangerment finding.