The fluids used for hydraulic fracturing in California oil wells contain dozens of hazardous chemicals linked to cancer, hormone disruption, and reproductive system damage, according to a new report by the Environmental Working Group.
In the analysis, “California’s Toxic Fracking Fluids: The Chemical Recipe,” the EWG deconstructs drilling companies’ use of 200 unique chemicals in nearly 700 wells across the state, with each company deploying around two dozen chemicals. These chemicals have the potential to contaminate drinking water, air, and soil and to harm human health, the EWG said.
“Fracking is inherently problematic because of the chemicals used in the fluid,” said Tasha Stoiber, EWG senior scientist and report co-author.
“Since California has one of the most comprehensive and transparent disclosure programs in the nation, it’s the best window we have on the specific chemicals drillers are injecting into the ground,” Stoiber said.
Fracking fluid is a mixture of water, chemicals, and sand that is pumped into underground shale rock formations to crack them and release oil and natural gas trapped there.
Of the chemicals added to fracking fluid in California, 15 are listed under the state’s Proposition 65 as known causes of cancer or reproductive harm, 12 are listed under the Clean Air Act as hazardous air pollutants known to cause cancer or other harm, and 93 are associated with harm to aquatic life.
In March, the EWG released a report “Toxic Stew” to give the public information on California’s contaminated fracking wastewater. The latest analysis gives a fuller picture of the process by revealing what’s pumped down fracking wells, the likely origin of some contaminants in wastewater, and the types of hazardous chemicals used, stored, or transported at fracking sites.
The EWG’s analysis shows why other state governments need to require drilling companies to disclose the chemicals they’re using. It underscores the urgent need for independent oversight of drilling in California and elsewhere, Stoiber said.
The EWG report recommends that state officials:
- Determine where less harmful alternatives can replace toxic chemicals currently used.
- Immediately halt operations that are injecting drilling wastewater into potential sources of drinking or agricultural water.
- Monitor groundwater in oil and gas areas and properly enforce model criteria developed under the California disclosure law.
“California leads the nation when it comes to providing more information about fracking chemicals to the public,” said Bill Allayaud, EWG’s California director of government affairs and report co-author. “But full disclosure is only the first step. Now it’s time for state officials to act aggressively to make sure these hazardous substances don't jeopardize human and environmental health.”