Air Emissions from Eagle Ford Oil and Gas Activity Expected to Quadruple over next Four Years

Well site located in Eagle Ford Shale play

Well site located in Eagle Ford Shale play

Late last week, the Alamo Area Council of Governments (AACOG) released a report outlining emission projections from oil and gas activity in the Eagle Ford Shale play, the most active drilling area in the country right now. Under the moderate drilling activity scenario, projections of air pollutants are expected to quadruple in the next four years. Even though this seems like a staggering prediction, it is likely an underestimation, given certain emissions are not accounted for in the inventory.

What does the report say?

The report assesses the emissions from oil and gas activity in the Eagle Ford Shale play and projects air pollution under three different development scenarios: low, moderate, and aggressive. Projections over the next several years indicate that we can expect substantial increases in smog-forming nitrogen oxide emissions (NOx), volatile organic compounds (VOCs), and carbon monoxide.

Ozone Season Projected VOC Emissions for Three Scenarios

Source: Alamo Area Council of Governments in cooperation with the Texas Commission on Environmental Quality and the U.S. Energy Information Administration

Ozone Season Projected NOx Emissions for Three Scenarios

Source: Alamo Area Council of Governments in cooperation with the Texas Commission on Environmental Quality and the U.S. Energy Information Administration

What is included in the emissions inventory?

There are three different types of wells in the Eagle Ford Shale development included in the emission inventory: dry gas wells, wet gas wells that produce condensate, and oil wells. The report calculates air emissions that are released in the Eagle Ford Shale during five main phases of well construction and production: exploration and pad construction, drilling operation, hydraulic fracturing and completion operation, production, and midstream sources. Emissions sources include drill rigs, compressors, pumps, heaters, other non-road equipment, process emissions, flares, storage tanks, fugitive, and some on-road vehicle emissions road traffic.

What does the report not say?

The report does not include emission projections from some key activities associated with oil and gas development, including:

  • “Non-routine emissions, such as those generated during upsets or from maintenance, startup, and shutdown activities, with the exception of blowdowns from gas wells.”
  • “construction of mid-stream facilities, building offices, quarrying of fracturing sands, pipeline construction, etc.
  • “generators and other equipment at camp houses and offices used by oil field workers”
  • “trucks that bring supplies to mid stream sources, worker camps, and other facilities not located at the well head.”
  • “production of cement, steel pipes, and other non-recycled material are not included in the emission inventory.”
  • “railroad activity related to Eagle Ford development, even though railroads are investing heavily in the area and more than half of the current rail activity at the Port of San Antonio is now related to Eagle Ford activity.”

In addition, the report does not estimate the contribution of air pollutants from oil and gas activity to ozone concentrations in San Antonio. Over the last several years, ozone concentrations in the San Antonio area have risen substantially and many attribute this surge to increased oil and gas activity in the neighboring Eagle Ford Shale play. By 2018, NOx emissions per ozone season day in the Eagle Ford will be roughly equivalent to the total NOx emissions per day from all current sources in the San Antonio region, including every car and truck on the road and every industrial facility like power plants and factories. VOC emissions per ozone season day in the Eagle Ford are expected to triple current emissions of all current air pollution sources per day in San Antonio.

What are the largest sources of emissions in the Eagle Ford?

According to the report by the AACOG, “47 percent of NOX emissions in 2012 from the Eagle Ford were emitted by drill rigs and well hydraulic pump engines. Compressors and mid-stream sources accounted for 39 percent of NOX emissions in 2012, but are expected to increase to 77 percent of total NOX emissions under the 2018 moderate scenario because of the significant increase in oil and gas production. The majority of VOC emissions in 2018 are estimated to be from storage tanks (47 percent) and loading loss (32 percent).”

Should we be concerned?

While burning natural gas is touted as a cleaner energy source than coal combustion, much of the equipment used in the drilling, production, processing, and transporting of natural gas and oil produces significant amounts of VOCs and NOx. These pollutants combine in the presence of sunlight to form ground-level ozone or “smog.”  Given the dramatic increase in projected emissions and the potential to lead to unhealthy air quality for those living in the Eagle Ford and nearby San Antonio, there is a critical need to mitigate air emissions from the oil and gas sector.

What can be done?

EDF has been working with natural gas producers and policy makers around the country to help mitigate air pollution in key states where the majority of oil and gas activity is taking place. Ohio, Colorado and Wyoming have all recently addressed fugitive emissions, demonstrating there are cost-effective technologies available and common sense policies that can be implemented to curb oil and gas air pollution. As natural gas and oil development continues to expand across Texas, adverse air impacts are likely to follow, absent sufficient emissions controls. It is crucial for the states to have strong standards in place, especially for a state such as Texas, which has experienced exponential production increases in a short period of time. Furthermore, it’s imperative that the state environmental agency, Texas Commission for Environmental Quality, install air monitoring networks early in the development of oil and gas operations to monitor the impact on air quality.

How is the Eagle Ford different from other shale formations?

As outlined in the AACOG report, the Eagle Ford Shale is known for high oil yields, unlike the Haynesville and Barnett Shale formations in northern Texas which primarily produce natural gas. As a result, equipment types, processes, and activities in the Eagle Ford may differ from those employed in more traditional shale formations.

This entry was posted in Air Pollution, GHGs, Natural gas, Oil, Ozone, Particulate Matter, San Antonio, TCEQ and tagged , , . Bookmark the permalink. Both comments and trackbacks are currently closed.

One Trackback

  • […] Air Emissions from Eagle Ford Oil and Gas Activity Expected to Quadruple over next Four Years By Elena Craft, PhD Well site located in Eagle Ford Shale play Late last week, the Alamo Area Council of Governments (AACOG) released a report outlining emission projections from oil and gas activity in the Eagle Ford Shale play, the most active drilling area in the country right now. Under the moderate drilling activity scenario, projections of air pollutants are expected to quadruple in the … […]