Ozone compliance said at risk

State should prepare for new EPA standards, official says

An Arkansas Department of Environmental Quality official said Thursday that central Arkansas should be on alert for new Environmental Protection Agency standards on ground-level ozone that threaten to push the area out of attainment and force it to implement programs to improve air quality.

Mark McCorkle, environmental program coordinator for the agency, told Metroplan’s Ozone Action Days Steering Committee that the Little Rock area has seen a decline in ground-level ozone for more than 20 years.

But meeting the new standard could be “difficult,” McCorkle said.

“We need to raise our level of concern again, I think, if the standard is going to change,” he said.

Ozone occurs naturally in the atmosphere but forms at ground level when car exhaust and industrial emissions react to high temperatures and sunlight. Exposure to ground-level ozone can intensify allergies or respiratory problems. Under worse weather conditions, high levels of ozone can create respiratory problems.

Current federal standards for ozone measure the fourth-highest ozone level for each of three years and average the numbers. To be in attainment, the average cannot exceed 75 parts of ozone per billion parts of air.

On Nov. 25, the EPA announced that it would change that standard to within the range of 65 parts of ozone per billion parts of air to 75. A new standard would become official Oct. 1.

Now, ozone alerts are issued when the ozone parts per billion exceed 75. Little Rock sits at 71 parts per billion when taking the past three years into account.

Due to mild, wet weather, Little Rock has had better ozone conditions and has issued no ozone alert days, meaning the Environmental Quality Department didn’t have to issue any warnings for people with respiratory disorders to curb their outdoor activity.

This summer was the fifth-coolest on record, said Chris Buonanno, science and operations officer for the National Weather Service in Little Rock.

“We set a record for the fewest number of days over 90 degrees,” he said.

When areas fall out of attainment, McCorkle said, officials have to implement programs or regulations to increase the air quality, regulations that can sometimes discourage industry from moving in.

Many programs — particularly federal ones — already exist in Little Rock to improve air quality and have helped contribute to the decreasing ozone levels, McCorkle said.

“We’re getting progressively better, which is a result of those programs, I think,” he said.

On Thursday, the Ozone Action Days Steering Committee also heard from contract promoters for Ditch the Keys, a week-long event that the group puts on each year to encourage modes of transportation other than cars. The event had 172 registrants this year, and Metroplan Executive Director Jim McKenzie said it was the best participation he’s seen.

In its Imagine Central Arkansas draft, Metroplan recommends maintaining high air quality, promoting Ozone Action Days, and promoting lower-emissions transportation and the infrastructure to support it. It also recommends giving local governments incentives to adopt policies that allow for more mixed-use, walkable areas.