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Fracking in Indiana: Environmental impacts

Hydraulic fracturing boom has public concerned
By Welleman (Own work) [CC-BY-SA-3.0 (], via Wikimedia Commons

[Part 2 of three-part article on hydraulic fracturing.]

Environmental costs of fracking.

There are costs to hydraulic fracturing beyond those recorded on the corporate books. Hazardous chemicals are typically used in the fracking process.

Oil and gas companies have strongly opposed regulations that would require them to identify the specific chemicals used in fracking, contending that they are trade secrets. Information that fracking operators are required to disclose in Indiana and other states is incomplete and not in a form that reveals the true chemical composition of all of the additives, making it difficult to test for contamination. Without proper monitoring, it is difficult to trace the source of contaminants or for public officials to determine whether contaminants in the air or water pose a danger to health.

Trade secrets or not, many people believe that their right to drink clean water and breathe clean air outweighs any company’s right to pollute the water and air for its own profit. Secrecy breeds distrust.

Ways in which hydraulic fracturing can impact the environment.

  • Fracking requires a high volume of water. From 70 to 140 billion gallons of water are used each year in the United States for hydraulic fracturing. Such a high demand can overburden a the water supply in a region, leading to a shortage of drinking water as well as a shortage of water for other industries, farming and ranching, and aquatic life.
  • Fracking requires large amounts of sand or other proppants. Shale gas wells can use more than four million pounds of proppants per well. The sand is mined at large excavation sites that are themselves sources of air pollution.
  • Fracking chemicals and pollutants in the wastewater are released into the air. Many volatile organic chemicals are used in fracking fluids or may be freed from the shale deposits as a result of fracking. They off-gas, evaporating into the air above surface containment compounds that hold the wastewater. High levels of benzene were measured near wells in Texas shale gas fields. People living near wells elsewhere have complained that the air was so bad they found it difficult to breathe. A Pennsylvania fracking wastewater impoundment caught fire and exploded.
  • Toxic chemicals are added to fracking fluid and produced by fracking. Although the chemicals added to the fracking fluid usually make up just a small percentage of the total volume of the fracking fluid, a very large volume of fracking fluid is used, so that the small percentage translates into a large amount of fracking chemicals. A four-million-gallon fracturing operation can use from 80 to 330 tons of chemicals. Many of the chemicals additives are known to be toxic to humans and wildlife and some are known to cause cancer: hydrocarbons, formaldehyde, methanol, ethylene glycol, petroleum distillates, hydrochloric acid, muriatic acid, and sodium hydroxide. Some of the chemicals are highly toxic in very small amounts. Benzene is toxic at levels over five parts per billion in water.
  • Fracking chemicals can pose a hazard for workers. Field studies by the National Institute for Occupational Safety and Health indicate that people who work at hydraulic fracturing operations can be exposed to hazardous levels of hydrocarbons. At least four workers have died since 2010 due to chemical exposure while transferring, storing, and measuring flowback fluid. (For a map of fracking accidents across the United States, see
  • Earthquakes have been linked to hydraulic fracturing. The fracking process, but more often, injecting wastewater from fracking into disposal wells, can trigger earthquakes. Geologists say that injecting fluid underground can make seismic faults more likely to slip, resulting in an induced quake. In July 2013, a leading seismology lab reported in the journal, Science, that powerful earthquakes from thousands of miles away can trigger swarms of minor quakes near fracking wastewater wells, followed by larger earthquakes months later. Pressure from the wastewater wells apparently stresses nearby faults, making them more susceptible to rupturing, which can then trigger damaging earthquakes. A level 5.7 earthquake that occurred in Prague, Oklahoma, in November 2011 was linked to wastewater injection. It destroyed 14 homes, and injured two people.

The area around Evansville, Ind., is at risk from the New Madrid and the Wabash Valley seismic zones, according to the U.S. Geological Survey (USGS). If earthquakes from thousands of miles away might cause quakes near fracking wastewater wells, then people who live in this area have a right to be concerned about hydraulic fracturing operations.

This is the second article in a three-part article on hydraulic fracturing:

Other articles by this author include: