But Jeremy Nichols of the environmental advocacy group, WildEarth Guardians, said the state's regional haze plan "obviously wasn't good enough" and that state regulators should be pushing PacifiCorp to update the Hunter and Huntington power plants in central Utah before the EPA requires it.
"The writing on the wall is pretty clear here," Nichols said. "Coal plants are dirty."
Dave Eskelsen of Rocky Mountain Power noted that in recent years his company has spent $2 billion some of it at the Huntington and Hunter plants on improvements to comply with the regional haze regulation and other Clean Air Act limits. An additional $1 billion to be spent over the next 10 years will go to further clean-air projects, including converting one of three coal-burning units at the PacifiCorp's Naughton plant in Wyoming to lower-pollution natural gas. Eskelsen said his company's plants comply with current regulations and will be in line with future regulations as they develop.
PacifiCorp now has 10,597 megawatts of generating capacity in the West. About 58 percent comes from coal-fired plants, 21 percent is from natural gas and 11 percent is from hydropower. Roughly 10 percent comes from wind energy and other renewables.
Under a court order in a lawsuit brought by WildEarth Guardians, the EPA had until Monday to decide whether Utah's plan was up to par. Carl Daly, who oversees EPA's air-quality programs in Utah and five other states, said state regulators are already working on the additional review of nitrogen oxides and particulate matter and intend to submit it this summer.
"We understand that the state is currently working with PacifiCorp to develop the analyses," he said.
Whether or not PacifiCorp needs additional controls, Daly said, can be determined only after the analysis is done.
Bryce Bird, director of the Utah Division of Air Quality, said his agency is already working on addressing the shortcomings raised by the EPA, and that the state will submit its own comments in coming weeks during a public comment period on the EPA's decision. But he pointed out there is good news in the EPA's current determination, too.
"They [at EPA] are approving major portions of the [Utah] plan, the ones that have the biggest impact on visibility," said Bird, pointing to sulfur oxides and smoke management.
Meanwhile, environmental groups say Utah's regional haze plan, ordered under widely supported 1977 amendments to the Clean Air Act, aims to not only clear up pollution in the national parks but also has the side benefit of improving health and protecting the economic benefits provided by the parks.
Nationwide, the haze plans will mean more than$7 billion in avoided health care costs $209 million in Utah alone.
"In order to restore the air quality," said Stephanie Kodish of the National Parks Conservation Association, "it's important big industrial-pollution sources use the best technology available."
Kodish said there are standard retrofit technologies to cut nitrogen oxides, which are in wide use in the East.