Wastewater from fracking could pollute surface water and drinking water sources
Risk analysts have concluded that the disposal of contaminated wastewater from hydraulic fracturing (fracking) wells producing natural gas in the intensively developed Marcellus Shale region poses a substantial potential risk of river and other water pollution. That conclusion, analysts say, calls for regulators and others to consider additional mandatory steps to reduce the potential of drinking water contamination from salts and naturally occurring radioactive materials, such as uranium, radium and radon from the rapidly expanding fracking industry. The new findings and recommendations come amid significant controversy over the benefits and environmental risks associated with fracking. The practice, which involves pumping fluids underground into shale formations to release pockets of natural gas that are then pumped to the surface, creates jobs and promotes energy independence, but also produces a substantial amount of wastewater.
"Even in a best-case scenario, an individual well would potentially release at least 200 cu meters of contaminated fluids," according to doctoral student Daniel Rozell, P.E., and Dr. Sheldon Reaven, associate professor and director of energy and environmental systems concentration in the Department of Technology and Society at Stony Brook University.
Disposal of the large amounts of fracking well wastewater that is expected to be generated in the Marcellus Shale region, which covers approximately 124,000 sq km from New York to West Virginia, presents risks from salts and radioactive materials that are "several orders of magnitude larger" than for other potential water pollution pathways examined in the new study.
The disposal of used hydraulic fracturing fluids through industrial wastewater treatment facilities can lead to elevated pollution levels in rivers and streams because many treatment facilities are not designed to handle hydraulic fracturing wastewater containing high concentrations of salts or radioactivity two or three orders of magnitude in excess of federal drinking water standards, according to the researchers. The wastewater disposal risks dwarf the other water risks, although the authors say a rare, but serious retention pond failure could generate a very large contaminated water discharge to local waters.
If only 10% of the Marcellus Shale region was developed, that could equate to 40,000 wells. Under the best-case median risk calculation that Rozell and Reaven developed, the volume of contaminated wastewater "would equate to several hours flow of the Hudson River or a few thousand Olympic-sized swimming pools." That represents a potential substantial risk that suggests additional steps should be taken to lower the potential for contaminated fracking fluid release, the authors say. Specifically, they suggest that "regulators should explore the option of mandating alternative fracturing procedures and methods to reduce the wastewater usage and contamination from shale gas extraction in the Marcellus Shale." These would include various alternatives such as nitrogen-based or liquefied petroleum gas fracturing methods that would substantially reduce the amount of wastewater generated.