The Environmental Protection Agency plans to issue a finding of endangerment for greenhouse gas emissions from commercial aircraft.

According to a rule making report, issued by the agency this week, the proposal will be released in April 2015.

An endangerment proposal, if approved, would act as an official acknowledgement by the EPA that aircraft emissions are harmful to public health and/or the environment. This acknowledgement would require, by law, the EPA to begin regulating said emissions.

"This is late, incredibly late, but it's still incredibly good news because EPA realizes it has to act itself," Vera Pardee, a lawyer with environmental advocacy group Center for Biological Diversity, told Bloomberg BNA earlier this week. "If it makes a positive endangerment finding, which we completely expect will happen, then it has no choice but to start regulating aircraft emissions independent of and regardless of what the international community does."

The Center for Biological Diversity and several other environmental groups sued the EPA earlier this year to force regulatory action on airline emissions. It appears their move has worked, but it could be some time before domestic emissions standards are established.

The process of finalizing the endangerment proposal could take up to a year, the EPA says, but the agency plans to issue an advance notice of proposed rule-making in concurrence with their finding of endangerment. The notice is one of the earliest steps in the regulatory process, meaning actual regulation is unlikely be passed until 2016.

The EPA says it expects the Civil Aviation Organization to adopt aircraft CO2 standards by February 2016 in anticipation of federal standards.