Sink or Swim: Water Disposal Issues
Disposal of “produced” water is another concern the industry is addressing with shale gas development. After a hydraulic fracture treatment, the fracturing fluid, mixed with water naturally present in the formation, begins to flow back through the well casing to the wellhead, creating flowback or “produced” water. The make-up of the produced water differs among different regions. “Flowback” of produced water can continue for several months after gas production. The produced water may contain naturally-occurring compounds, such as Naturally Occurring Radioactive Materials (“NORM”) and benzene, and can account for less than 30 percent to more than 70 percent of the original fracturing fluid volume. In some states, produced water is injected into underground wells and stored. Control of the injection is regulated by the Underground Injection Control Program (UIC) of the Federal Safe Drinking Water Act. The program is designed to confine the produced water within the injection zone in a manner that prevents contact with fresh water-bearing formations.
In Pennsylvania, produced water is recycled. Recycling waste water from fracking reduces the environmental footprint of drilling, lowers transportation costs and lessens reliance on groundwater or municipal sources of water. State-wide test results have shown that recycled water meets all federal radium standards.Testing on the state and local level is conducted on a regular basis and is supported by natural gas companies.
Operators are exploring ways to use and recycle the water produced from hydraulic fracturing. Significant volumes of recycled water would reduce the demand for surface water withdrawal and conventional waste discharge capacity. Water usage and proper water management are important considerations when producing shale gas. The industry, in partnership with its investors, is working to streamline and further improve efficiencies and technology to better manage water usage.