EPA chief Scott Pruitt announced that he will sign paperwork to repeal the Clean Power Plan, an Obama administration rule to combat climate change rule by reducing greenhouse gas emissions from coal and natural gas power plants.

The repeal makes good on a campaign promise by then-candidate Donald Trump, who called the rule “stupid” and “job killing.”

Pruitt’s announcement, which was made at a mining equipment company in the coal-dependent community of Hazard, Kentucky, was met with enthusiastic applause.

“The war on coal is over,” declared Pruitt, who said the Obama administration had overstepped its authority. “It’s Congress that passes legislation that gives us direction, that gives us our orders as far as how we administer the statute,” Pruitt said Monday. “The last administration simply made it up.”

Environmentalists and Democrats aren’t cheering. According to the Environmental Defense Fund (EDF), “the Clean Power Plan would be the most significant step in U.S. history toward reducing the pollution that causes climate change.” The EDF also said that it would create new opportunities to continue development of the clean energy economy. “And we will all benefit from less severe temperature increases, less dangerous sea level rise, and fewer ferocious storms.”

According to the Union of Concerned Scientists, who obtained data from the U.S. Department of Energy, the United States is second only to China in terms of its contribution of Carbon Dioxide Emissions from the Consumption of Energy, accounting for 5490.63 Million Metric Tons of it in 2011.

Coal-fired power plants are the largest emitters of carbon. The Clean Power Plan was intended to reduce emissions from the electricity sector by 32 percent by 2030.

There’s considerable disagreement on the cost v. benefits of the plan. The EPA under Obama said it would produce $20 billion in economic benefits. The EPA under President Trump says the figure is closer to $500 million.

The actual economic impact of the plan is difficult to gauge, since its implementation has been delayed by a series of lawsuits brought against it by the fossil fuel industry.