The Trump administration will sign off this week on new rules that will drastically roll back restrictions on methane-gas emissions that were introduced by President Barack Obama in an effort to combat climate change, The Wall Street Journal reports. The Environmental Protection Agency’s new rules will reportedly end the requirement that oil-and-gas producers have ways to detect methane leaks in their systems, and remove the largest pipelines from EPA oversight of smog and greenhouse-gas emissions. Methane accounts for around 10 percent of U.S. greenhouse-gas emissions, and is believed to be about 25 times worse than carbon dioxide when it comes to trapping the earth’s heat. The oil-and-gas industry is the nation’s biggest methane polluter. The Journal reports that many of the country’s biggest oil, gas, and fracking companies have major offices near Pennsylvania—a swing state for Trump ahead of the election.