Air Pollutants Under Cover
It was a mystery. Louisiana environmental officials in Baton Rouge wanted to know why ozone levels were spiking above EPA's limits to protect health on days when they should have been lower. Efforts to control regulated sources of ozone-producing chemicals had been successful. So, where were the emissions?
Researchers at EPA's Office of Research and Development (ORD) took to the sky above the Mississippi River to investigate. They armed themselves with a pollution-detecting infrared camera and hopped on a helicopter to get special images of barges transporting gasoline. On the ground, they aimed their cameras at various gasoline storage tanks.
The mission: To search for clues to the missing sources of smog-forming chemicals that contribute to ozone. The study was a collaborative effort with the Louisiana Department of Environmental Quality and EPA's Region 6 Office which is responsible for the Agency's environmental programs in the state.
Researchers discovered plumes of ozone-forming chemicals, invisible to the naked eye, that were leaking from barges as well as tanks. The vapors found their way out through valve seals, vent systems and other places that should not be leaking. Scientists discovered a significant number of leaks, and some were very large.
Louisiana officials discussed the findings with barge and tank owners. Since the emissions indicated the loss of a valuable product, the owners had a vested interest in repairing the leaks. Considerable progress has been made to fix the leaks and reduce emissions in Baton Rouge.
As a result of the research, EPA is applying the technology to monitor and reduce air pollutants in other parts of the country, said David Williams, lead scientist of the Louisiana study in the Office of Research and Development. Originally designed for military use in night vision equipment, the technology is growing in popularity among regulators and industry. It is being used to find leaks in industrial plants, refineries and operations where fuel is stored.
Williams and his colleagues have used the infrared cameras in other studies to investigate fugitive or unknown sources of pollutants. Next summer, they will test the technology on tankers carrying gasoline and liquefied natural gas that come into port.