BISMARCK (AP) - The American Lung Association gave North Dakota high marks for air quality Tuesday but said the rapid development in the western portion could become an area of concern.
The group collected data from air quality monitors in eight of the state's 53 counties. All eight counties were given an "A'' grade for ozone pollution, and six of the eight counties earned an "A'' grade for particle pollution.
Bob Moffitt, the spokesman for the ALA in North Dakota, said the data was collected from 2010-2012 and doesn't completely reflect the state's current conditions, which have changed rapidly in recent years as diesel-fueled truck traffic has increased along with natural gas flaring in the booming western North Dakota oil patch.
Terry O'Clair, the director of the state Department of Health's Air Quality Division, said he was pleased with the ALA's report. He said North Dakota typically is one of the few states that performs well across the board in terms of air quality and that the state's ozone and particle levels were well within the guidelines established by the Environmental Protection Agency.
But he said the increased truck traffic has raised particle pollution in parts of the oil patch to higher levels compared to the rest of the state.
"I wouldn't put a red flag on it, but it's an area that we've got to continue to watch," said O'Clair, who said in recent years his department began monitoring the air quality in Williston.
Moffitt said the ALA was concerned with the increased amount of flaring in the oil patch.
"We're really not sure what the air quality is in an area that's doing so much flaring, and that's frankly a concern," he said.
O'Clair said flaring in the Bakken region is less of a concern because the natural gas being burned off is sweet and doesn't contain much hydrogen sulfide.
O'Clair and Moffitt both said they've heard from western North Dakota residents who have concerns about the area's air quality.