The Environmental Protection Agency has officially replaced an Obama-era rule that would have set limits on air pollution from coal-fired power plants. The Trump administration says the Clean Power Plan — which never went into effect — was an overreach of the EPA’s power.

The new Affordable Clean Energy rule allows states to set their own goals for greenhouse gas emissions. Environmentalists worry that, with less federal oversight, the rule could lead to more air pollution-related deaths.

READ MORE: How The Rule Replacing The Clean Power Plan Might Affect Indiana

Two years ago, Indiana passed a law that said the state couldn’t enact environmental rules more stringent than federal ones without a review. That could leave Indiana — a heavily coal-fired state — without a baseline to follow.

States will have three years to submit their plans to reduce coal-fired emissions under the new rule.

READ MORE: ACE Rule Unlikely To Steer Utilities Toward More Coal Says IEA

Indiana Environmental reporting is supported by the Environmental Resilience Institute, an Indiana University Grand Challenge project developing Indiana-specific projections and informed responses to problems of environmental change.