This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

A coalition of Arizona businesses has joined the push for additional pollution controls at Utah's Hunter and Huntington coal-fired power plants, a move they hope will influence the Environmental Protection Agency as the deadline for the agency's decision on the matter looms.

Fifty Arizona business owners sent a letter to the EPA last week, urging the agency to consider the impact of its decision on the Grand Canyon and surrounding communities, which, according to the letter, support more than 7,000 Arizona jobs and generates $10.6 billion in consumer spending.

Most who signed the letter, drafted by industry advocacy group Protect our Winters, are tied to the state's outdoor recreation industries.

The Rocky Mountain Power's Hunter and Huntington coal-fired power plants, located in Emery County, are the focal point of the current debate over Utah's regional haze plan. Under the terms of a legal settlement, the EPA has until June 1 to determine whether to accept Utah's proposed haze plan, which would take credit for the 2015 closure of Rocky Mountain Power's Carbon plant, or to reject the state's plan and implement its own, which would require additional pollution controls at the remaining two plants.

Emissions from those two plants are believed to contribute to the buildup of haze at eight national parks in the Southwest, including the Grand Canyon and Utah's Mighty Five, according to an EPA report.

The EPA's Regional Haze Rule primarily aims to improve haze-related visibility at national parks and other protected landscapes. Environmentalists, especially the National Parks Conservation Association, have argued that the EPA's alternative plan would cut the emissions that contribute to haze formation in Utah's national parks by 87 percent, greatly improving visibility in those regions.

But Bryce Bird, director of the Utah Division of Air Quality, said the state's plan has already reduced haze formation at the Grand Canyon and other southwestern parks, and will continue to do so.

"Protecting the national parks is important to us as well," he said. "The visibility goals [of the Regional Haze Rule] were outlined with a 2064 target, so we have always had a long-term approach to this."

The state also says the EPA's pollution-control plan would have a negligible impact on visibility and require hundreds of thousands of dollars to implement — costs that would be passed on to Rocky Mountain Power's Utah customers.

But those who rely on tourism at the Grand Canyon to make a living believe the state's plan is costly, too.

"We see very noticeable haze on some days from a number of sources, and these two coal-fired power plants are the source of some of that pollution," said Danny Giovale, owner of Flagstaff, Ariz.-based Kahtoola, a manufacturer of outdoors equipment. "It does have an impact on the recreational value of northern Arizona … when you stand on the south rim of the Grand Canyon and look out on these hazy days — people have traveled from all over the world to see this natural wonder, and it's being obstructed by some pretty heavy pollution."

Brady Black, an outfitter who helps equip private river trips in the Grand Canyon, said he worried about the health of future generations — i.e., his future customers.

"We're spraying toxic emissions, and basically everyone is a downwinder," he said.

Angel Collinson, a Utah resident and professional skier, said watching the outdoor companies she works with struggle and even fail drove her to join Protect Our Winters. But she said she is concerned about the way air pollution is affecting Utah's image abroad.

"You can't place a value on views, on starry skies at night," she said. "What's the value of keeping our identity what it is?"

Kate Cannon, superintendent of the Southeast Utah Group of national parks, said the number of visitors attending parks under her purview, including Canyonlands and Arches, has remained strong even though the parks are hazy for about 34 percent of the year. But people have begun to notice, she said.

"We are getting visitor comments asking why it's hazy and saying that they're disappointed," she said. "Or saying that they remember it differently."

Twitter: @EmaPen