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.

ABC News’ Stephanie Ramos talks to former EPA Administrator Gina McCarthy on the Trump administration’s rollback of clean air and water protections.

EPA Administrator Lee Zeldin outlined an aggressive plan to dismantle the "holy grail" of climate regulation, the endangerment finding