The Environmental Protection Agency (EPA) proposed transferring some responsibility in regulating coal ash disposal from the federal government to the states last week.

The proposal could save the coal-fired power plants and utilities between $31 million and $100 million in compliance costs, according to the EPA.

“Today’s coal ash proposal embodies EPA’s commitment to our state partners by providing them with the ability to incorporate flexibilities into their coal ash permit programs based on the needs of their states,” EPA Administrator Scott Pruitt said in a statement. “We are also providing clarification and an opportunity for public comment – something that is much-needed following the public reaction to the 2015 coal ash rule.”

When the coal ash regulations were enacted under former President Barack Obama, the EPA took full responsibility for maintaining compliance. The agency was not authorized to transfer oversight to the states until Congress amended the Resource Conservation and Recovery Act in 2016, which allowed states to enact their own, federally approved regulatory structure.

The 2015 rules on coal ash disposal created new and more aggressive rules on inspecting waste sites and pollution levels while requiring liners in new waste pits to prevent contaminants leaking into water sources, The Washington Examiner reported.

Lawsuits blocked the EPA from implementing the 2015 rule. The litigation is still in court.