In this video segment adapted from Need to Know, learn about health concerns regarding exposure to chemicals used in natural gas drilling. An animation ...
This media asset was adapted from "Need to Know."
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Adapted courtesy of WNET: "Need to Know."
Hydraulic fracturing, also known as fracking, is a process that injects fluid at high pressure deep underground to open and enlarge cracks in rock formations. This process stimulates the flow of natural gas, increasing the amount that can be extracted. Most fracking fluids are water based. A solid material, such as sand or ceramic beads, is added to the fracking fluid to keep the fractures open and permeable after the pressure is reduced. Other chemical additives are used, depending on the characteristics of the particular well. For example, some chemicals reduce friction to allow pumping at a higher rate than with water alone; others help dissolve minerals; and some prevent bacterial growth.
Many of the chemicals used in fracking fluids can also be found in foods, cosmetics, soaps, and household cleaners. However, that does not mean that they are safe; dosage is an important factor when evaluating hazardous materials. Although the total concentration of chemical additives in fracking fluid is generally less than 2 percent, millions of gallons of fluid are typically used to drill a well. That means that thousands of gallons of chemicals could be used that might potentially impact human health and the environment.
In 2005, the Energy Policy Act exempted hydraulic fractured wells from regulation under the Safe Drinking Water Act. Some states may require disclosure of ingredients to state environmental agencies or health officials, but fracking fluids are largely unregulated. Mining companies each have their own proprietary formula. Some chemicals used in the fluids are known, but the exact compositions are kept confidential because they are claimed to be trade secrets. (The formula of a particular fluid may provide an advantage over other companies.) However, concerns over possible contamination of water resources from fracking fluids has led to controversy over whether the industry should be allowed to keep the formulas confidential.
Currently it is difficult to assess the connection between health problems and the fracking process because so little is known about the composition of the fluids. Even if a company discloses the chemicals it uses, the exact concentrations of chemicals may not be known. The Environmental Protection Agency has asked a number of fracking service providers to provide detailed information about their fluids as part of a study on the effects of fracking on drinking water and public health; research is due to be finished in 2012. Until more is known about the effects of the hazardous chemicals contained in fracking fluids, some people might argue that the industry should follow the precautionary principle—that it is their responsibility to protect the public from harm—and use safer chemicals in their fluids. Some companies are already making more environmentally friendly fracking fluids available.
- Define fracking and explain the process in general.
- What are some possible environmental impacts of fracking? Explain why some people are concerned about the fracking process.
- Do you think that gas drilling companies should be compelled to tell the public which chemicals they are using? Why or why not?
- What scientific evidence so far suggests a possible link between fracking and human illness? How would you design an investigation to establish a possible link between fracking and negative impacts on human health?
- Discuss the advantages and disadvantages of federal regulation of the fracking and drilling industries.
National Health Education Standards
2 (Grades: 9-12 ): Students will Analyze the influence of family, peers, culture, media, technology and other factors on health behaviors.
Benchmarks for Science Literacy
3B/H1 ( Grades: 9-12 ): In designing a device or process, thought should be given to how it will be manufactured, operated, maintained, replaced, and disposed of and who will sell, operate, and take care of it. The costs associated with these functions may introduce yet more constraints on the design.
3 (Grades: 9-12 ): The Nature of Technology
3A (Grades: 9-12 ): Technology and Science
3A/H1 (Grades: 9-12 ): Technological problems and advances often create a demand for new scientific knowledge, and new technologies make it possible for scientists to extend their research in new ways or to undertake entirely new lines of research. The very availability of new technology itself often sparks scientific advances.
- 3A/H1 (Grades: 9-12 ): Technological problems and advances often create a demand for new scientific knowledge, and new technologies make it possible for scientists to extend their research in new ways or to undertake entirely new lines of research. The very availability of new technology itself often sparks scientific advances.
3B (Grades: 9-12 ): Design and Systems
- 3A (Grades: 9-12 ): Technology and Science