Imagine going to your yearly physical only to have your doctor say that you need major surgery before he has even examined you. When asked why, he produces the results of a computer simulation based on actuarial data and medical history. In spite of the good results of your medical tests, the doctor concludes that you are in dire health.
Wouldn't you want a second opinion from someone who knows the difference between a computer model and the real world?
Computer models, of course, can provide all kinds of useful information particularly when empirical data is lacking. But it doesn't require a post-graduate degree to recognize that when it comes to our own health or the actual condition of the air we breathe, physical measurements should trump speculative models. And in Texas, we are blessed to have sophisticated means to measure air quality through ambient monitors and other high-tech tools.
But, academics, activists and some regulators increasingly rely on manipulated computer models to justify environmental regulations. A new study on air emissions associated with natural gas production in the Barnett Shale by Eduardo Olaguer of the Houston Advanced Research Center (HARC) is such a modeled study which "simulates ozone formation in the vicinity of a hypothetical natural gas processing facility." (emphasis added) Not surprisingly, the study concludes that natural gas production can cause higher levels of ozone and thus poses "a severe challenge to oil and gas producers in the DFW area."
Oddly, air quality has been improving in the nine county DFW ozone non-attainment area while Barnett Shale natural gas production has soared. (See graph below) Real world data from the TCEQ's air quality monitors and in-depth air surveys rebut the claims of Dr. Olaguer's study. TCEQ's Chairman Brian Shaw notes that "state-of-the-art 24-hour air monitors in the Barnett Shale area are showing no levels of concern for any chemicals."
Dr. Olaguer's study is of the same methodological cloth as a much bally-hooed study by former EPA Assistant Administrator Al Armendariz. The models in both studies extrapolate (assume) that hypothetical worst-case scenarios are representative of average emissions. This approach leads to implausible conclusions that ozone emissions from Barnett Shale production are twice as large as all mobile source emissions in the area. If natural gas production added ozone precursor emissions in volumes twice that of cars and trucks, ozone levels would be sharply rising. Air quality monitors tell a different story.
TCEQ's data gathered by models and sampling shows that NOx from cars and trucks in the DFW region are 15 times higher than NOx from natural gas production facilities.
Dr. Olaguer's pre-occupation with volatile organic compounds (VOC) emissions is also misguided. He attributes some extremely high ambient concentrations of formaldehyde, a VOC, to a pipeline compressor station in Lake Arlington. But this data on formaldehyde derives from another study whose authors determined that the formaldehyde levels measured in the air had originated not from the compressor station but from sources off that site.
Emissions of VOCs from Barnett Shale production are increasingly a non-problem. The natural gas in the Barnett Shale formation is what geologists call "dry gas." With little to zero associated liquids, VOCs are unlikely emitted from most dry gas wells.
The rapid increase in drilling, processing and transporting natural gas in and around DFW certainly warrants ongoing review of any air quality impacts. Science is critical to this effort, but not all science is created equal. Citizens legitimately concerned about healthy air should ask for the real-world facts-facts more accurately revealed by monitored measurement of ambient conditions.
Kathleen Hartnett White is director of the Armstrong Center for Energy and Environment at the Texas Public Policy Foundation. She was commissioner and chairman of the Texas Commission on Environmental Quality from 2001 to 2007."