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Published: June, 2015; Vol 12, Num 1

 

Tackling Flowback Hazards on Fracking Sites

Our May issue of Lifelines outlined how responsible drilling practices can help reduce the environmental and public health concerns that often accompany fracking. This month, we take a look at an issue every fracking site has to confront – how to prevent hazards to worker health and safety during flowback operations. Flowback refers to process fluids from the wellbore that return to the surface during and after hydraulic fracturing occurs.

As the fracking industry matures, operators will employ more Laborers across the United States and Canada. The U.S. Chamber of Commerce estimates that fracking has already created 1.7 million jobs and expects this number to double by 2035. In light of this, working with contractors to promote responsible drilling practices and protect workers on fracking sites will only become more important.

Fracking involves injecting a mix of water, sand and chemicals into the ground under high pressure to open fissures and allow gas to flow into the well. Between 10-30 percent of this water flows back to the surface as a waste product that must be collected and disposed of properly.

Much like produced water, flowback fluids are then routed to production tanks for storage prior to disposal. It’s here that workers use handheld gauges to periodically check fluid levels via access hatches on top of each tank. In addition to the hydraulic fracturing fluids originally pumped into the well, returned fluids contain volatile hydrocarbons and other potentially harmful substances from the fractured shale.

The Benefits of Disclosing What’s in Frack Water

Many employers are hesitant to share details about what makes up their frack water with the public. However, disclosing this information can help decrease community concerns and encourages the substitution of less toxic alternatives when possible. Disclosure is now being required in some areas.

Chemical disclosures are critical to allow health care providers to diagnose or rule out occupational exposures for workers. Many health care providers are unaware of the potential exposures during fracking operations, especially the issue of taking home toxics (e.g., boots contaminated with drilling mud) to family members. Increasing awareness through chemical disclosure is a much-needed first step.

Several worker fatalities have occurred during flowback operations. According to the National Institute for Occupational Safety and Health (NIOSH), these deaths were caused by acute chemical exposures during tank gauging and flowback fluid transfers. Further NIOSH investigation suggests that workers were overwhelmed by the inhalation of hydrocarbon gases. Often, these fatalities occurred when workers were performing their duties alone.

When workers open hatches on production tanks to gauge fluid levels, a plume of hydrocarbon gases and vapors can be rapidly released due to the internal pressure present in the tank. Many of the substances in flowback fluids, including volatile hydrocarbons, are extremely toxic and can be deadly at high concentrations. Exposure to these substances can affect the eyes, breathing and nervous system as well as cause abnormal rhythms in the heart.

When inhaled, hydrocarbons cause a narcotic effect that causes disorientation, dizziness and light-headedness. In a confined area, hydrocarbon plumes can also lead to asphyxiation by displacing enough oxygen that workers can’t breathe.

NIOSH and their industry partners recommend several practices that employers can follow to reduce the potential for occupational exposures during flowback operations:

  • Use a buddy system so workers do not have to gauge tank levels on their own.
  • Develop alternative tank-gauging procedures so workers do not have to routinely open hatches to manually gauge tank levels.
  • Provide hazard awareness training to ensure flowback technicians, water haulers and drivers understand the risk for chemical exposures when working on and around flowback fluids.
  • Monitor workers to determine their exposure to volatile hydrocarbons and other contaminants.
  • Use appropriate respiratory protection in areas with the potential for chemical exposure as an interim measure until engineering controls are implemented.
  • Establish emergency procedures to provide medical response in the event of an incident.

The LHSFNA’s pamphlet Responsible Drilling: How Fracking Can Be Done Safely gives information on how to address the environmental and public health concerns often associated with fracking. For more resources on responsible drilling practices and methods, contact the Occupational Safety and Health Division at 202-628-5465.

[Nick Fox]