The San Antonio metropolitan area is struggling to cut its ozone level to meet federal standards and in fact saw the level creep higher at a key monitoring site from 2012 to this year, officials say.
The worst of the ozone season has wrapped up for the year, but at the monitoring site at Camp Bullis, the three-year average of ozone increased from 80 parts per billion to 81 ppb over the past year. The federal standard, last updated in 2008, is 75 ppb.
Camp Bullis tends to record the highest levels in the area because it is downwind from pollution sources.
"With the ozone design value rising between last year and this year, it's hard to say we're doing adequately what we need to do," said Peter Bella, the natural resources director at the Alamo Area Council of Governments.
AACOG officials have been working with local utilities, cities and industries to try to get them to reduce their emissions voluntarily. They have also launched an educational campaign to reach individuals.
An unanswered question remains how much ozone the development of the Eagle Ford Shale play is contributing. AACOG is working on an emissions inventory study that should provide a breakdown of sources. The study, which is due to the Texas Commission on Environmental Quality by the end of the year, should also help explain why the ozone level ticked up this year.
"It'll be the first time that we've got an inventory that is comprehensive of all the emissions in the region," Bella said.
In July, a draft study from AACOG and funded by the TCEQ showed that air pollution from Eagle Ford could increase ozone levels in Bexar County by as many as 7 ppb by 2018. But Bella said that study was "incomplete" and that AACOG does not stand by that estimate.
Once completed, the emissions inventory should enable scientists to perform more accurate pollution modeling and will help officials identify areas where emissions can be reduced, Bella said.
Ozone is created when emissions from industrial facilities, electric utilities, vehicle exhaust, gasoline vapors and chemical solvents are baked in sunlight. Ground-level ozone can cause health problems, especially for children, the elderly and people with lung problems. It is one of six pollutants that the Environmental Protection Agency sets standards for as required by the Clean Air Act.
While the San Antonio area is in violation of the federal standard, it has not been designated by the EPA as being in nonattainment. The concern is that if the EPA lowers its standard from 75 ppb in the near future and San Antonio has not cut its ozone level, the area could be hit with the nonattainment label.
If that happens, the metropolitan area will have to work with federal and state officials to devise a mandatory plan to cut air pollution. In the Houston and Dallas-Forth Worth metropolitan areas, which are both in nonattainment, steps included vehicle emissions tests, EPA officials said. Those two areas both had monitoring sites with three-year averages of 87 ppb this year, according to TCEQ data.
In July, AACOG officials sent the EPA a "Path Forward" letter outlining the actions the area was taking to slash its ozone levels. They highlighted how CPS Energy had plans to replace coal-fired power plants with cleaner technology in the coming years and improvements made by four cement manufacturing facilities. They also touted efforts by VIA Metropolitan Transit, the San Antonio Water System and the city.
The EPA replied in August, essentially asking what else the region was planning, given its lack of success in reducing ozone so far.
"It seems that nearly all of the measures/programs mentioned in the document are completed or ongoing," the letter from the EPA said. "We did not see any new actions or enhancements to existing programs. This was surprising, considering the current/recent ozone levels in the area."