This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated.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.

Federal environmental officials will descend on Salt Lake City next week to request Utahns' help in solving a long-running dilemma — determining whether the state's regional haze implementation plan meets EPA expectations.

The Environmental Protection Agency in December called for the public's input on two federal proposals for addressing the state's plan for clearing the skies in its national parks. The 60-day public comment period is ongoing and has already yielded tens of thousands of comments, but environmentalists and state officials hope Tuesday's public hearing will draw allies out of the woodwork.

The first EPA proposal would declare the state plan adequate and leave Utah to continue implementing it until the next haze review period begins in 2018. The second option would have the EPA declare the state plan to be only partially acceptable and require the installation of additional pollution controls at Rocky Mountain Power's Hunter and Huntington coal-fired power plants.

Environmentalists have said that without those pollution measures, the plan would do little to improve visibility at vistas in Bryce Canyon National Park and other outdoor attractions. The Sierra Club, HEAL Utah and other groups have urged the public to speak out against the state's plan, arguing that the EPA's alternative has the greatest potential to reduce overall emissions.

State officials argue the controls required by the EPA alternative would have a negligible impact on visibility and not achieve the goals of the regional haze rule.

The technology in question, selective catalytic reduction, would reduce emissions of nitrogen oxide, said Alan Matheson, executive director of the Utah Department of Environmental Quality. While NOx does contribute to the formation of haze, Matheson said, that's only half the equation; ammonia nitrate must also be present to react with NOx to form haze.

Southern Utah's desert landscape doesn't produce a lot of ammonia nitrate, Matheson said. Consequently, he said, reducing emissions of NOx would do little to improve visibility in Utah's national parks. Given that installing selective catalytic reduction at the Hunter and Huntington plants could cost $580 million, Matheson said DEQ just couldn't justify the minimal improvement in visibility that would result.

"We want to be sure that when we're asking for investments of public and private resources," he said, "that it is for the greatest benefit."

In December, after environmentalist-led litigation prompted the EPA's long-overdue review of Utah's plan and the formulation of its two proposals, EPA Region 8 asserted that the public review of both options was necessary "due to the complex nature of the state's plan and the air quality analyses it contains" and "to ensure our final decision is based on a thorough assessment of technical information and comments."

Tuesday's public hearing will involve two sessions, one from 1 to 5 p.m. and a second from 6 to 8 p.m., both at the downtown Salt Lake City Library.

Twitter: @EmaPen —

EPA public hearing on haze mitigation plan

O Where • The Salt Lake City Public Library When • Tuesday, 1 to 5 p.m. and 6 to 8 p.m.