BR area gets new ozone goal

The five-parish area around Baton Rouge was given a new goal to meet in reducing ozone pollution Tuesday when the U.S. Environmental Protection Agency announced final designations for a lower standard.

The area around Baton Rouge, including the parishes of East Baton Rouge, West Baton Rouge, Ascension, Iberville and Livingston, is required to meet the more stringent standard for ozone pollution of 75 parts per billion. The previous standard was 80 parts per billion.

“The air didn’t get worse. The standard just got lower,” said Tim Bergeron, environmental chemical specialist with the state Department of Environmental Quality.

Ozone forms when nitrogen oxides and hydrocarbons from car exhaust, industrial activities and other sources combine in the air during hot and sunny days.

When there isn’t much wind, this ozone accumulates and can cause breathing and health problems, especially for vulnerable populations such as children.

The ozone standard is calculated by taking the fourth highest 8-hour-average ozone reading of the year and averaging three years of those readings.

Only one of the nine air-quality monitors in the five-parish area is over the 75 parts per billion standard and that one is at LSU at 78 parts per billion based on 2008-2010 air quality information.

The five-parish area has been classified as “marginal,” which is the least severe of classifications and means the area has three years to come into compliance with the lower standard, Bergeron said.

The Clean Air Act doesn’t require any additional actions be taken in areas classified as marginal, because it’s assumed federal regulations will help bring an area into compliance, he said.

Those federal regulations combined with the restrictions the state has put in place to meet previous ozone standards will remain in place.

“None of that is going to change,” he said.

However, Bergeron said, experience in the Baton Rouge area has shown that more will have to be done to meet the lower standard.

“We’re going to have to add some new controls in the Baton Rouge area,” Bergeron said.

He said the state is doing computer modeling to see what emissions that contribute to ozone formation need to be reduced, and from where, he said.

In addition, the modeling will look at the whole state, not just the five-parish area as they previously did, he said. Results of that modeling will likely be available next summer.

The reason for the state-wide computer modeling is that 2011 air quality information shows three additional areas exceed the standard and those are Calcasieu, Jefferson and Bossier parishes.

For these areas, the EPA has a voluntary program called “Ozone Advance” where areas work to reduce ozone-causing pollution. EPA can decide whether an area will then be in or out of attainment, he said.

“They’re given a chance to do voluntary reductions,” Bergeron said.

DEQ will continue to work with areas in the state that are close to the lower standard, like Lafayette which is at 72 parts per billion, he said.