"Review of regulations issued under the Obama Administration, with the possibility of their modification or repeal, was the main focus of interest on Clean Air Act issues in the 115th Congress and in the executive and judicial branches in 2017 and 2018. This will likely continue in the 116th Congress--although with a different emphasis, given the new majority in the House. U.S. Environmental Protection Agency (EPA) rules to regulate greenhouse gas (GHG) emissions from power plants, cars and trucks, and the oil and gas sector have been of particular interest."
CRS Report for Congress, R45451
Congressional Research Service: https://crsreports.congress.gov/