Digging into Shale Gas and its Effects on Public Health

Written by: Samantha Malone, MPH, CPH, Manager of Science and Communications, FracTracker Alliance and DrPH Student, Environmental and Occupational Health Dept., Graduate School of Public Health, University of Pittsburgh, and Jill Kriesky, PhD, Assistant Director, Southwestern Pennsylvania Environmental Health Project
Copy editors: Jennifer Kolker, MPH, Co-Principal Investigator, Pennsylvania Public Health Training Center; Kurt Holliday, Communications Specialist, Pennsylvania Public Health Training Center

Figure 1. PA Production and Waste From Unconventional Wells:
July 2012 to December 2012. Data source: PA DEP. Map: FracTracker.org

You hear about it daily in the news; natural gas is an immense, domestic energy source for the United States. Economic analysts and the industry promote this fossil fuel as a solution to our need for foreign energy and a cheaper, cleaner-burning fuel for household use.  But with these benefits also come significant risks.

Today’s natural gas is not found in shallow pockets tapped by drillers generations ago. It is tightly packed in deep shale deposits requiring considerable effort to extract it.

Drillers pump millions of gallons of water and chemicals underground to hydraulically fracture the shale and release the gas.  The process involves hundreds of truck trips to deliver the site materials and haul away the waste. Blowouts, fires, and traffic incidents add to burdens already shouldered by rural emergency responders and health care practitioners. Truck trips, diesel-powered compressors, and silica sand used during hydraulic fracturing also worsen air quality. Waste water improperly injected into deep wells (See Figure 1) has induced earthquakes (~4.0 magnitude).[1]

Despite these potential health risks, public health professionals’ input was missing from early regulatory discussions about the benefits and costs of shale gas extraction.[2] While the public health workforce has weighed in more recently, additional issues need action.  Most importantly, chemical mixtures returned to the surface after drilling should be actively monitored. Private drinking water wells in the vicinity need pre- and post-water quality tests.  The air, water, and soil pathways to potential human contamination exposure require systematic study.  And finally, micro-seismic monitoring of hydraulic fractures and wastewater injection should be conducted.  Responsiveness to the results of these studies can reduce the potential environmental health impacts posed by this industry today and in the future.

Figure 2. Drilled (orange) and permitted (pink) unconventional wells in PA as of 1-4-13.
Data source: PA DEP. Map: FracTracker.org

1.  For a comprehensive list of health concerns associated with unconventional natural gas extraction, see Korfmacher, Jones, Malone, and Vinci (2013).
2.  Goldstein BD, Kriesky J, Pavliakova B. (2012). Missing from the Table: Role of the Environmental Public Health Community in Governmental Advisory Commissions Related to Marcellus Shale Drilling. Environ Health Perspect, 120(4): pp. 483–486.