A matter of life and breath

When it comes to protecting natural resources from the impacts of natural gas drilling, the focus in our area has been mainly on the water supply. And that makes sense, given that we live in a watershed for about 15 million people. But water is not the only vital resource being threatened. As discussed in last week’s article “Gas drilling in the air,” so is the air we breathe.

The extent of the risk is evident in a recent study by the Department of Environmental and Civil Engineering of Southern Methodist University ((www.edf.org/documents/9235_Barnett_Shale_Report.pdf)), which focuses on the Dallas/Fort-Worth (DF-W) area. It measures the impact of actual drilling activity on air quality in the so-called “DF-W non-attainment area.” The phrase “non-attainment” in that Federal designation refers to the fact that the nine Dallas/Fort-Worth counties have been unable to attain minimum federal ground ozone standards since 1997. Because of that, the area is subjected to intensive and regular air testing, and because it is situated over the Barnett Shale, it provides a good real-world example of the effects of massive drilling activity.

Among the report’s findings are that smog-forming compounds emitted by Barnett Shale activities average about 191 tons per day (tpd) in that area. To give a sense of scale, it notes that the oil and gas sector contributes more to smog than vehicular traffic in the five most drilling-intensive counties. Remember, that’s urban traffic in a metropolis of over six million people.

The study also examines other pollutants like greenhouse gases and toxic chemicals called hazardous air pollutants (HAPs). It concludes that current emissions of greenhouse gases from drilling activity in the area, at approximately 33,000 tons per day of CO2 equivalent, are “roughly equivalent to the expected greenhouse gas impact from two 750 megawatt coal-fired power plants.” The production of hazardous air pollutants from Barnett Shale activities, which includes carcinogens such as benzene, carbon disulfide and trimethylbenzene, was described as “significant,” with emissions of 6.4 tons per day on average, and peak summer emissions of 17 tons per day.

The study does not give specific parameters for determining how damaging those hazardous air pollutants number could be, but an ambient air monitoring analysis for natural gas drilling done for the town of DISH, TX gives us some idea of the dimensions of the potential problem. On reviewing that report, MacArthur Fellowship Award-winning chemist Wilma Subra concluded, “Acute impacts to health will occur with these concentrations of chemicals in the air. The cancer and neurotoxins will also have an impact over the long term.”

We don’t feel that the Supplemental Generic Environmental Impact Statement (SGEIS) recently released by the New York State Department of Environmental Conservation gives adequate weight to such real-world findings. Instead, it creates mathematical models for measuring emissions from a single theoretical 10-well drilling pad. It also does simulations taking into account the impact of having one adjacent well pad a kilometer distant. But it’s not clear to us that this can successfully capture the impact of thousands of well pads over decades.

Even on its two-pad basis, the report concludes that, under some of its simulations, there will be “exceedances,” that is, the emissions created will exceed current state or federal air standards. It suggests that that can be mitigated by making the emissions stacks higher—or building fences 150 meters from the well pad (coincidentally, a distance roughly equal to the new, reduced New York setback of 460 feet).

Admittedly we’re laymen, but we don’t see how those fences will keep the poisonous gases concentrated at the sites from escaping the 150-meter boundary over time. Multiplied by thousands, that will surely increase background pollution in the area year after year. And raising stacks may send the pollutants further away, but will scarcely eliminate them from the atmosphere altogether.

The Dallas/Fort Worth study suggests some mitigation strategies not addressed by the SGEIS. Some of them may not apply to our area, but others might be worth looking into. But even with mitigation, it is clear that with gas drilling in our area, we are going to have to get used to air of heavy industrial, not rural, quality.

We would like to see state analysts make more of an effort to estimate the cumulative effect of thousands of well pads, over time as well as space. And data from the Dallas-Fort Worth report and any others that study real-world drilling areas should surely be taken into account. Abstract modeling can only go so far. Finally, we think New York State, and Pennsylvania for that matter, should simply prohibit exceedances to begin with. The build-a-fence-to-keep-the-bad-air-in solution fails to comfort us.

Dr. Punnybone

No, no, I told you to make him look stupid