While the United States has a long history of oil and gas development, the recent rise in activity has been rapid and steep. Between 2000 and 2014, more than 173,000 new natural gas wells went into production, while the average rate of oil production grew nearly 50%. As of 2014, there were more than 1.1 million active oil and gas wells nationwide.[ii]
Much of the most recent development can be attributed to the shale boom, which has intensified drilling in many places and introduced it in others. Increasingly, operations have expanded to include, alongside well pads, the processing and transportation facilities needed to move the gas and oil to market. Despite a recent dip in operations, industry and state governments continue to plan for increased development in the coming years.
Expanded activity has also increased the range of potential environmental and health impacts. In turn, a strong focus on pollution of the water we drink has increasingly been complemented by questions about risks to the air that we breathe.
This shift in part stems from growing attention to the climate impacts of natural gas—which is pure methane, a greenhouse gas over 80 times more potent than carbon dioxide. A recent study estimated that during 2002-2014, US methane emissions increased more than 30%, likely in large part due to the shale gas and oil boom.[iii] The US Environmental Protection Agency (EPA) projects that methane emissions from the oil and gas industry could increase 25% in the next decade.[iv]
Both conventional and unconventional oil and gas operations involve heavy industrial processes, which by definition release a variety of health-harming pollutants. Pennsylvania’s air emissions inventory shows that between 2011 and 2013, volumes of total volatile organic compounds (VOCs) emitted by unconventional gas wells increased 70% and benzene 66%.[v] In the Uinta Basin of Utah, VOCs emitted by the oil and gas industry increased nearly 80% between 2006 and 2012 and now account for almost all VOC pollution in the region.[vi] A study in the Eagle Ford Shale of Texas projected that by 2018, VOC emissions could be 200-450% higher than in 2012, depending on the level of development.[vii]
Communities living on the frontlines of oil and gas development have long been the first to notice the impacts of worsening air quality and to sound the alarm for the general public, decisionmakers, and the media. Recent studies have found that health symptoms are more frequent and risk levels higher among people living closer to wells and facilities than among those further away.[viii]
In addition, the health symptoms reported by residents living in proximity to oil and gas wells and facilities are often quite similar. Studies in several states have identified similar patterns in potential exposures and resulting symptoms, in particular respiratory problems, eye and throat irritation, headaches, nausea, and stress.[ix]
Given these trends, it is not surprising that oil and gas field residents nationwide are asking basic questions: “What’s in my air?” and “Why is it making me sick?” Yet both regulators who oversee the oil and gas industry and policymakers determining its course have only been able to give partial, ambiguous answers.
Residents, organizations, and researchers have increasingly taken on the search for more solid answers. This survey paper discusses many of the different air monitoring methods currently being used in community-based projects that are designed to increase understanding of oil and gas pollution. It also considers the reasons why—in the face of increasing emissions and reports of health problems—more monitoring is necessary to understand the air quality impacts from the oil and gas industry and, ultimately, to ensure that impacted residents get the information they need and deserve to protect their health.
 US Energy Information Administration. “Number of Natural Gas and Gas Condensate Wells,” historic data; and “US Field Production of Crude Oil,” historic data.
[ii] FracTracker Alliance, “Over 1.1 million active oil and gas wells in the US.” http://www.fractracker.org/2014/03/active-gas-and-oil-wells-in-us
[iii] Turner, A. J., D. J. Jacob, J. Benmergui, S. C. Wofsy, J. D. Maasakkers, A. Butz, O. Hasekamp, S. C. Biraud, and E. Dlugokencky. “A large increase in US methane emissions over the past decade inferred from satellite data and surface observations.” Geophysical Research Letters 43, 2016.
[iv] USEPA fact sheet. “EPA’s strategy for reducing methane and ozone-forming pollution from the oil and natural gas industry.” 2015. http://www3.epa.gov/airquality/oilandgas/pdfs/20150114fs.pdf
[v] PA Department of Environmental Protection. “Air Emissions Data from the Natural Gas Industry.” Comparison of VOC data from 2011 and 2013 spreadsheets. www.dep.pa.gov/Business/Air/BAQ/BusinessTopics/Emission/Pages/Marcellus-Inventory.aspx
[vi] Western Regional Air Partnership, Oil and Gas Emissions Workgroup, Phase III Inventory. Comparison of VOC data from 2006 and 2012 spreadsheets. www.wrapair.org/forums/ogwg/PhaseIII_Inventory.html; Utah Department of Environmental Quality, “Ozone in the Uinta Basin: Strategies and Tactics.” http://www.deq.utah.gov/locations/U/uintahbasin/ozone/strategies/standards.htm
[vii] Alamo Area Council of Governments. Oil and Gas Emission Inventory Update, Eagle Ford Shale. 2015. Calculations based on data provided for tons of VOCs released per ozone season day.
[viii] Nadia Steinzor, Wilma Subra, and Lisa Sumi. “Investigating Links Between Shale Gas Development and Health Impacts through a Community Survey Project in Pennsylvania.” NEW SOLUTIONS, February 2013; T. Colborn, K. Schultz, L. Herrick, and C. Kwiatkowski. “An exploratory study of air quality near natural gas operations.” Human and Ecological Risk Assessment: An International Journal, 2013; Lisa M. Mckenzie, Roxana Z. Witter, Lee S. Newman and John L. Adgate, Human health risk assessment of air emissions from development of unconventional natural gas resources. Science of the Total Environment March 21, 2012; and Rabinowitz PM, Slizovskiy IB, Lamers V, Trufan SJ, et al. “Proximity to natural gas wells and reported health status: results of a household survey in Washington County, Pennsylvania.” Environmental Health Perspectives, 2015.
[ix] For a summary of the health study literature through 2014, see David R. Brown, Celia Lewis, and Beth I. Weinberger. “Human exposure to unconventional natural gas development: A public health demonstration of periodic high exposure to chemical mixtures in ambient air.” Journal of Environmental Science and Health. 2015.