Rocky Mountain Power may shutter a unit at the Dave Johnston Power Plant in an attempt to comply with new pollution standards.

Rocky Mountain Power may shutter a unit at the Dave Johnston Power Plant in an attempt to comply with new pollution standards.

A final decision on the eastern Wyoming unit’s future remains years away. The utility could opt to install new pollution controls at the facility instead of closing it.

But the problem underscores the challenges facing Rocky Mountain Power as it aims to bring its aging fleet of coal-fired power plants into compliance with Environmental Protection Agency regulations.

The 220-megawatt unit is one of four at the coal-fired power plant just east of Glenrock. Under the EPA plan, Rocky Mountain Power can adopt a lower level of pollution controls and retire the unit by 2027 or make an estimated $81 million in emission upgrades to keep the unit running. The utility has five years to make a decision and comply.

The conundrum before Rocky Mountain Power is not unlike one facing the owner of an old car, said Dave Eskelsen, a company spokesman.

“You have a piece of machinery that has a certain life in it. Does it make sense to buy that new transmission or get a new set of tires,” Eskelsen said. “It might make sense to retire the thing and get something new.”

Any upgrades to the unit will ultimately be paid for by ratepayers over time, he noted. A decision to shutter the unit will therefore be “based on analysis of what is in the best interests of customers,” Eskelsen said.

Dave Johnston employs 189 people full time across all operations. Any reductions in staff resulting from the unit’s closure would assume attrition, retirements and placements elsewhere in the company, Eskelsen said.

The situation facing Dave Johnston is not unique, said Shannon Anderson, an organizer at the Powder River Basin Resource Council. Coal-fired power plants are an increasing liability to utilities as regulations to limit harmful emissions increase, she said.

“For that facility, all the units are pretty old,” Anderson said, noting that the plant was commissioned in 1958. “It is hard for us to envision a scenario where ratepayers are paying for control after control. At some point you have to cut your losses and look at other alternatives.”

Early this month, the EPA released a final plan for curbing pollution and limiting haze from power plants in Wyoming. The plan calls for more stringent emission controls at two Jim Bridger power plant units near Green River, one Wyodak plant unit near Gillette and three units at Laramie River Station near Wheatland.

EPA officials estimated the plan would reduce nitrogen oxide emissions by 65,000 tons annually.

Basin Electric Power Cooperative, which owns and operates Laramie River, assailed the plan, saying the new regulations would cost $750 million. EPA estimated the cost of the upgrades at $557 million.

Wyoming released its own plan for curbing emissions in 2011. Many of the measures proposed in that plan were adopted by the EPA in 2013 when the agency released its own draft for limiting pollution.

But the federal edition came under heavy criticism from utilities and Wyoming lawmakers, who said the proposed measures were costlier than the ones in the state plan and would force early retirements of plants across Wyoming.

The measures at Jim Bridger, Wyodak and Laramie River all went beyond what the state called for.

The final EPA plan represents an improvement over the agency's draft, Eskelsen said. Proposed upgrades at two Naughton Plant units near Kemmerer and an additional Dave Johnston unit were not included in the final document.

The EPA also set a 2027 closure date for the Dave Johnston unit, the same as Rocky Mountain Power's projected date for retiring that facility.

“It is closer to the state plan, which was something that the company supported as reasonable as far as what it could achieve,” Eskelsen said.

Rocky Mountain Power, a division of Portland, Ore.-based PacifiCorp, will upgrade the two units at Jim Bridger in 2015 and 2016. The EPA plan gives the utility until 2021 and 2022 to complete upgrades at the remaining two units.

The company is keeping the cost of the upgrades confidential, Eskelsen said. EPA estimated the total capital cost to upgrade the first two units at $177 million and $148 million respectively. The agency did not outline the total capital investment for Jim Bridger in its final plan.

The EPA estimated the total capital cost of upgrading Wyodak at nearly $120 million. Eskelsen said Rocky Mountain Power is analyzing its options at that plant.

Environmentalists applauded the new measures but questioned the EPA's decision to pull back some of its initial recommendations.

EPA spokesman Richard Mylott said the agency recalculated its cost and pollution reduction analyses during the public comment period and concluded that the more stringent measures were not needed.