Tahlequah Daily Press

January 8, 2013

Many factors contribute to air quality index reporting

By ROB W. ANDERSON
Staff Writer

TAHLEQUAH — Quality assurance is a sort of measuring-stick system used in many scenarios to ensure the intended goal of a situation.

Air quality is a vital component that’s monitored when checking environmental conditions, and maintaining acceptable levels of criteria pollutants is the main objective of concern for heavily-populated areas like Oklahoma City or Tulsa.

Major metropolitan areas generally produce more pollution than those towns or cities found in rural areas, but that’s not to say that readings that generate what’s known as the Air Quality Index, or AQI, do not pertain to these rural or non-metro areas, said Oklahoma Department of Environmental Quality Environmental Program Specialist Curt Goeller.

The ODEQ and organizations like the Cherokee Nation’s Environmental Division work together to gather the needed data to produce the AQI, which is established by the measurements of a previous day’s monitored concentrations of criteria pollutants, which includes Clean Air Act-mandated pollutants like particulate matter, ozone, carbon monoxide, sulfur dioxide and nitrogen dioxide.

The level of contamination in the air from all potential sources –  both natural and man-made – provides indication of the quality of the air people breathe, according to the ODEQ’s website. Because the ODEQ has “a certain number of monitors around the state which limits the data” that can be gathered, the AQI reading may not reflect the exact level of criteria pollutant for the varied areas that are monitored throughout Oklahoma, said Goeller.

“We have to make generalizations based on our monitors,” he said. “We can’t say that’s going to reflect everywhere we’re monitoring. There are some moderate readings that we occasionally get, like last week we had one day for particulate inhalants.  We think it was from a fire in Nebraska and the smoke getting blown down here.”

The most recent AQI, or the reading shown for the state on the www.airnow.com website, was “good,” or there were no harmful levels of ozone, particulate matter or carbon monoxide detected in the air. The AQI is an Environmental Protection Agency required daily public report that the ODEQ makes in each metropolitan area with a population of more than 350,000. The report is also used to forecast, or predict, expected levels of the criteria pollutants, which is vital when these pollutants are expected to rise to unhealthy levels.

The AQI report can provide health-sensitive individuals with the necessary information to take precautionary measures for the following day, which may present moderate to hazardous levels depending on the time of the year or other human-created factors.

“A moderate AQI reading could be caused by smoke from fireplaces, controlled burns or even windblown dust,” said Cherokee Nation Environmental Programs Specialist April Hathcoat. “If you look at the wind maps on Mesonet (http://www. mesonet.org), you can see the wind patterns in Oklahoma that can cause dispersion in one area of the state versus another. So a higher reading in our part of the state could be just the right combination of a pollutant source plus wind direction.”

On a day with an AQI reading of 1 to 100, or moderate, the pollutant-specific cautionary statement for ozone states “unusually sensitive people should consider limiting prolonged outdoor exertion.”

The Cherokee Nation has been monitoring the air for 16 years, said Cherokee Nation Environmental Division Director Ryan Callison, who noted the division checks levels for several pollutants, especially those pollutants mandated by the Clean Air Act.

“We monitor for just about all of them,” he said. “From ozone, nitrogen dioxide, sulfur dioxide, particulate matter to about everything else under the sun.”

The Cherokee Nation started one of the first tribally-operated clean air programs and has five air-monitoring locations, including a site in Tahlequah, Stilwell, Roland, Newkirk and Pryor.

For more information on the Cherokee Nation air-monitoring sites, go to Cherokee.org and search Environmental Programs, and to learn more about ODEQ or the daily AQI reading, go to www.deq.ok.us or www.air now.com, respectively.