Contrary to suggestions by the Environmental Protection Agency (EPA), the Clean Power Plan (CPP) does not interfere with the authority of FERC or threaten the affordability and reliability of the nation’s electricity supply, according to a trio of former Commissioners.

EPA Administrator Scott Pruitt announced in October that the Trump administration would issue a proposed rule to end the controversial CPP, which established for the first time federal limits on carbon emissions for the nation’s power plants. The Obama-era EPA overstepped its legal authority when it issued the CPP, Pruitt said.

But “EPA’s suggestion in the proposed repeal that the CPP may tread impermissibly onto the functions and authority of FERC…is unfounded,” according to a filing at EPA by former Federal Energy Regulatory Commission Chairmen Norman Bay and Jon Wellinghoff and former Commissioner John Norris.

“The CPP is fully consistent with EPA’s traditional regulatory role, is similar in form and function to prior Clean Air Act programs affecting the power sector, and preserves the authority of FERC in the field of energy policy. While EPA and FERC regulate some of the same entities, their statutory aims are distinct, and the CPP respects the differences in authority between the two agencies.”

In the proposed repeal, EPA argued that the CPP threatens “to impose massive costs on the power sector and communities.” But, according to Bay, Wellinghoff and Norris, the CPP “is consistent with ongoing trends in the power sector, is achievable at reasonable cost, and does not pose threats to reliability.”

The Obama administration unveiled the final version of the CPP in August 2015. The plan, which embraces renewables, solar and wind power, but not so much natural gas, calls for states to reduce emissions by 32% below 2005 levels by 2030.

Under the CPP, states must develop and implement plans that ensure power plants in their state — either as single plants or as a collective group — achieve goals for reducing carbon dioxide (CO2) emissions between 2022 and 2029, and final CO2 emission performance rates by 2030. The CPP gives states the option of choosing between either an emissions standards plan or a state measures plan to reduce emissions. They would also have the option of trading emissions rate credits with other states.

The Trump administration has estimated that the proposed repeal of CPP would provide up to $33 billion in avoided compliance costs in 2030.

The CPP has been on hold pending legal challenges working their way through the courts. Twenty-seven states — among them Oklahoma, where Pruitt was then the state’s attorney general — have sued over the CPP, arguing that it is an overreach by EPA. In February 2016, the U.S. Supreme Court temporarily blocked implementation of the rule until all legal challenges have been resolved.

According to a biannual plan released in December, EPA plans to completely repeal the CPP by October and roll back other Obama-era regulations throughout the year, including rules governing new sources of methane emissions and the definition of what constitutes Waters of the United States.

Originally appointed to FERC in 2006 by President George W. Bush, Wellinghoff was named Chairman in 2009 by President Barack Obama. Bay and Norris were both appointed to FERC by Obama.

EPA is accepting public comment on the proposed repeal of the CPP through April 26. EPA’s website indicates that more than 19,000 comments have already been filed to the docket.