Jeffrey D. Allred, Deseret News
Air quality suffers as an inversion covers the Salt Lake valley Thursday, Jan. 23, 2014. The EPA said it is considering lowering the ground level ozone standard to better protect people's health. But industry experts say the more stringent rule would be the most expensive regulation in history and will hike energy costs.

SALT LAKE CITY — The U.S. Environmental Protection Agency moved Wednesday to reduce ground level ozone with its announcement of a proposed rule that would signficantly lower the standard and result in increased industry controls.

The proposal, anticipated for two years, was immediately hailed by environmentalists and criticized by the oil and gas industry and conservatives.

"By EPA’s own conservative estimates, the ozone proposal would be the single costliest regulation in U.S. history," said Institute for Energy Research Senior Vice President Dan Kish. "Meanwhile, our air is cleaner than it’s been in decades. Instead of celebrating that progress, EPA insists on trying to squeeze water out of a rock."

In Wednesday's announcement, the EPA administrator said the agency is proposing to strengthen the standard from 75 parts per billion and take it to a range of 65-70 parts per billion. The agency will take comments on a standard as low as 60 parts per billion, although McCarthy said the science is less clear about benefits to public and environmental health.

Noting the standards were last revised in 2008 and that ozone levels across the country have dropped by a third since 1980, McCarthy stressed in a teleconference that the new proposal is based on extensive scientific research aimed at protecting the health of the American public, particularly the young.

"The science clearly tells us that ozone poses a real threat, especially to growing children," she said. "Exposure to ozone is disruptive, expensive, frightening and tragic."

According to the agency's analysis, the strengthened standard will prevent as many as 960,000 asthma attacks by children and around 1 million missed school days. The government also anticipates that anywhere between 750 to 4,300 premature deaths will be avoided because of the stronger standard and that 1,400 to 4,300 asthma-related emergency room visits will be eliminated.

Ozone is not a particular emitted pollutant but is the result of a complex chemical reaction that occurs when certain precursor pollutants — such as volatile organic compounds or nitrogen oxides — interact with the sun. The Wasatch Front smog problem typically occurs in the heat of the summer as the ground level ozone forms and then is trapped on the valley floor.

In Utah, air quality regulators have been concerned that a tougher ozone standard will leave rural areas out of compliance with federal Clean Air rules, particularly in places like the Uinta Basin, which struggles with a wintertime anomaly of spikes in ground level ozone.

Regulators say that while oil and gas producers are voluntarily moving to reduce emissions in the Uinta Basin, there's little other industry to target to rein in ozone formation. The state has also struggled with combatting ozone drift or ozone "transport" — pollution that wafts in from other states.

Some groups urged the EPA to adopt the most stringent standard under consideration.

''This long-awaited action bodes well for all Americans, including the millions of asthma sufferers, children and seniors —the most vulnerable among us," said John Walke, clean air director at the Natural Resources Defense Council. "Yet there's medical evidence of adverse health effects even at the lower end of the range recommended by the scientists. So we urge EPA to set the standard at 60 ppb.''

Some leading Republicans, however, said a new, tougher standard unfairly penalizes rural America and accomplishes nothing if even large metropolitan areas can't come into compliance.

“Major metropolitan areas in states like California and New York — where smog is the worst — cannot meet the existing standard even after years of non-compliance. We should be targeting these problem areas before devastating rural economies in states with cleaner air," said Sen John Thune, R-South Dakota.

Thune is running national legislation that would block implementation of any new ozone standard until 85 percent of the non-compliant counties meet the existing smog standard.

Beyond the tightening of the public health standard, the EPA is proposing to extend the ozone monitoring season for 33 states and to add a secondary, "environmental" standard for plants, trees and ecosystems, noting that repeated exposure to ozone stunts growth of trees and interferes with crops yield.

EPA will now take public comments on the 60-70 ppb range. The agency has to meet a court-ordered deadline of October 2015 to finalize a standard and states will have until 2020 to come up with plans to implement the standards.

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