CASPER — Time’s up for unit 2 of the Jim Bridger Power Plant.

After state and federal officials failed to establish updated pollution control standards for the unit ahead of its Dec. 31 compliance deadline, Gov. Mark Gordon signed a temporary emergency suspension order to keep the unit operating for another four months in accordance with the Clean Air Act.

If the dispute is not resolved by April 30, or if Environmental Protection Agency (EPA) Administrator Michael Regan rejects the extension, unit 2 will be required to shut down. Unit 1 could meet the same fate next December.

An analysis by University of Wyoming economics professor Timothy Considine estimated that the abrupt closure of unit 2 would cost the state $33.2 million in annual tax revenue and eliminate 404 full-time-equivalent positions statewide. Of those job losses, 327 would occur in Sweetwater County, including 65 at the power plant, 108 in coal mines and 154 in adjacent industries.

The governor’s office hopes it won’t come to that.

“I’m very optimistic that we’ll reach some kind of an agreement,” said Randall Luthi, Gordon’s chief energy advisor. “We just don’t know yet.”

Jody Ostendorf, congressional and intergovernmental liaison for EPA Region 8, wrote in an email to the Star-Tribune that “EPA intends to issue a proposed decision on this plan revision for public comment in the near future,” and said the agency “is not in a position to comment on this upcoming action or potential litigation over Wyoming’s regional haze plans.”

U.S. coal plants are required to limit their output of nitrogen oxides, or NOx — harmful air pollutants that cause respiratory diseases and environmental damage. Wyoming’s plan to retrofit its coal plants with pollution controls was approved by the EPA in 2014.

At the Bridger plant, however, the cost of reducing NOx emissions proved a significant barrier. Operating utility Rocky Mountain Power installed the required technologies at units 3 and 4, but with units 1 and 2 scheduled to be converted to natural gas peaking facilities in 2024, the utility deemed pollution controls uneconomical. In 2019, Rocky Mountain Power came up with an alternative: reducing the units’ electricity production to lower their NOx output to acceptable levels.

“We still think that plan provides satisfactory compliance with regional haze requirements, and is a sound plan, both from compliance with the Regional Haze Rule and cost to consumers,” said Dave Eskelsen, a spokesman for Rocky Mountain Power.

State regulators agreed; the EPA looked to be on board, too. Wyoming submitted its alternative plan for federal approval in May 2020. But the agency didn’t finalize the change before President Donald Trump left office, and after the Biden EPA reevaluated the proposal, it notified Wyoming in June of this year that it would not take any further action on the plan.

“It’s just been very disappointing and somewhat confusing,” Luthi said. “EPA was with us all the way — until they weren’t.”

According to Luthi, the EPA has yet to communicate its objections directly to the state.

“They’ve never given us reasons of why this just doesn’t work — why it doesn’t meet the regional haze guidelines,” Luthi said.

In Tuesday’s email, Ostendorf offered two such reasons.

“The state’s revision would remove longstanding requirements that the Jim Bridger power plant install modern controls to limit its visibility- and health-harming nitrogen oxides pollution, and does not address [Rocky Mountain Power’s] current plan to convert Jim Bridger units 1 and 2 to natural gas in 2023,” Ostendorf wrote. “Accordingly, the 2023 date is not currently enforceable through state or federal regional haze plans.”

Conservation groups, meanwhile, say the plan relies on misleading assumptions that yield invalid conclusions. Public comment submitted to the Wyoming Department of Environmental Quality in 2019 — when existing permit restrictions already limited the plant to 84 percent of potential capacity, according to WyoFile — argues that because the alternative plan assumes that the four Bridger units operate at maximum capacity, it overestimates how significantly NOx emissions would be reduced.

The governor’s office anticipates three possible outcomes over the next few months.

It’s been six weeks since Gordon sent a strongly worded letter to the agency, urging regulators to approve the state’s plan and warning that Wyoming would sue if no action was taken in the next 60 days. During that time, Luthi said, negotiations have continued, but nothing has been resolved.

Ideally, the state and EPA will reach an agreement before the end of April, he said. But if the EPA rejects Wyoming’s proposal, it’ll have to explain its rationale, which could enable the state to modify the plan accordingly.

“Then we at least have some information with which to talk to them about,” he said. “So I hope that opens up the door wider to negotiation.”

If the two parties can’t agree and the EPA doesn’t act, the state may follow through on Gordon’s Nov. 15 threat and sue.

For now, at least, Bridger unit 2 remains in regulatory limbo. While Eskelsen declined to speculate on what Rocky Mountain Power would do if the unit had to close, he emphasized that the planned conversion to natural gas will require months of permitting and planning. Such closures are economically sensitive to ratepayers, he said, and can’t be taken lightly.

“When we remove a network resource from the transmission network, it always must be done with a certain amount of forethought and planning,” Eskelsen said. “It’s not something that the company would normally do. And that’s one reason why we would hope for resolution of this issue, because proven utility practice requires these steps to be taken in a fairly deliberate way.”