The EPA says it's going to revise the federal fuel efficiency standards for cars and trucks, which environmentalists fear could resurrect the gas guzzlers that used to roam the roads decades ago. For this episode of Parts Per Billion, we give the keys to climate reporter Abby Smith, who tries to explain a very complicated and messy regulatory situation. For one, she says, there's the issue of California, which has the power to set its own efficiency standards for cars and is likely not on board with the Trump administration's efforts to roll those standards back. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.