A Georgia coal plant cannot go forward until it receives an air-pollution permit limiting its carbon-dioxide emissions, Fulton County Superior Court Judge Thelma Wyatt Cummings Moore ruled Monday. The ruling marks the first time a judge has used the Supreme Court’s classification of CO2 as a pollutant to regulate emissions from an industrial source. Moore’s decision overturns a previous ruling that had allowed the Longleaf Energy Plant, Georgia’s first new coal facility in more than 20 years, to go forward. Environmentalists say the case sets a heartening precedent. “We will be taking this decision and making the same arguments to push for an end to conventional coal,” says Bruce Nilles of the Sierra Club, which is in active litigation over dozens more coal plants across the country. Adds the club’s Patti Durand, “I can’t be more thrilled. It’s a huge ruling. This is a new day in the United States, and I’m thrilled.”