by Christina Nagy-McKenna, Enerdynamics Instructor,
and Bob Shively, Enerdynamics President and Lead Instructor

On June 3, 2015, the U.S. Environmental Protection Agency (EPA) released its draft “Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources.” While it should be noted that the study’s results are still in draft form and are not yet official agency policy, the study found no evidence that hydraulic fracturing or “fracking” has extensive effects on U.S. drinking water supplies.

Possible impacts of fracking include excessive water consumption and a risk of water contamination. Here’s a quick look at each and what the EPA study concluded:

Water consumption

Fracking is very water intensive, with the average well requiring 1.5 million gallons. This number jumps to 4 million gallons if only horizontal wells are factored into the equation. In its study, the EPA looked closely at how water moved throughout the fracking process. When water is acquired for fracking, it competes with other uses such as municipal water systems and farming. 

The EPA found that, depending on what part of the country the gas well is located, the water source may be surface water, ground water, or reused fracturing wastewater. In western states that have a more arid climate it is more likely the water used for fracking is from the surface and ground waters. In the East, producers usually use surface water. Reused water is found most often in Pennsylvania.

Producers need to be aware of the geologic conditions and climate in which they operate so as to avoid negatively impacting the drinking water. For example, if ground water is drawn down too aggressively, it can take more out of an aquifer than what it can naturally recharge. Also, using too much surface water may alter how a stream flows. In a few locales, competition for water resources may be important, but overall the impacts of water acquisition have not proven significant.

Water contamination

In looking at various stages of the fracking process, factors contributing to possible water contamination include:

• chemicals that can spill and leech into the soil
• wastewater if inadequately treated and discharged
• the movement underground of fluids due to a production well
  

Controlling these potential hazards is important as the EPA found that between the years 2000 and 2013, close to 9.4 million people lived within a mile of a well that was being fracked. Also, drinking water sources for 6,800 public water systems serving 8.6 million people were also within a mile of a hydraulically fractured well during this time period. 

In preparing the report, the EPA did find some instances where impacts on drinking water occurred but said the number of instances is small relative to the number of fracked wells drilled in recent years. This led the EPA to state that it “did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States.”

Next steps

The EPA’s draft is out for public review and comment, and we expect many parties on both sides of the fracking debate will participate. Once the report is final, it should provide more knowledge to allow state agencies to develop effective regulation that allows fracking to continue while protecting water resources from potentially negative impacts.

References:

“Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources,” United States Environmental Protection Agency, Office of Research and Development, Washington D.C., June 2015. 

 “EPA Blesses Fracking,” Silverstein, Ken, Fortnightly’s Spark, 2015.

 “EPA’s Fracking Finding May Prove a Boon for Industry,” Neuhauser, Alan, U.S. News and World Reports, June 5, 2015.