If all goes as planned, Xcel Energy is applying for its last federal air-pollution permit for a coal-fired power plant in Colorado.

But environmentalists worry that is a big “if” as long as the Trump administration is in power, and now they are asking the Colorado Department of Public Health and Environment to include the Comanche Generating Station’s projected closure date of Jan. 1, 2031, in the Pueblo power plant’s latest Title V air permit.

They hope putting the date in a permit that needs Environmental Protection Agency approval will guarantee that Xcel, the largest utility company operating in Colorado, will shutter its last coal-fired power plant in the state by that deadline.

“I really want to emphasize the need to ensure that these retirement dates, which Xcel has committed to and everybody has agreed to, are established and set in stone via this Title V air permit,” said Jeremy Nichols, a senior advocate for the Center for Biological Diversity.

“Right now, the federal government has launched an unprecedented assault on states like Colorado who are trying to do their part to confront the climate crisis and protect clean air and to enable a transition from coal to clean energy.”

Colorado’s utility companies have been planning for nearly two decades to shutter their coal-burning power plants and transition to cleaner alternatives, including natural gas, solar and wind power. Comanche is the largest coal-burning power plant in the state, and two of its three operating units still create electricity from coal.

Xcel is on track to shutter Comanche’s Unit 2 in September and remains committed to closing the plant’s Unit 3, which generates 750 megawatts of electricity, by January 2031, said Michelle Aguayo, a Xcel Colorado spokeswoman. Unit 1 is already closed.

“We continue to make significant progress towards our emission reduction goals approved by the state, which would require us to retire our coal units by (the end of) 2030,” Aguayo wrote in a statement. “We’re working with the administration and our states to continue delivering customers safe, clean, reliable energy while keeping our customers’ bills as low as possible.”

But President Donald Trump and EPA Administrator Lee Zeldin want the United States to continue burning coal, saying it is needed now more than ever to fuel a growing demand for electricity.