It has only been a short while that the state has looked for contamination of the state's aquifers by newly-refined oil and gas drilling techniques that use injection wells, but it didn't taken long to make some disturbing discoveries.

The Center for Biological Diversity (CBD) reviewed state documents that report at least nine of the wells, used to dispose of water loaded with noxious chemicals and materials extracted using hydraulic fracturing (fracking), contributed to the illegal disposal of 3 billion gallons of dangerous wastewater into Central Valley aquifers.

Another 19 injection wells may also have contaminated aquifers, the state said. The aquifers provide irrigation for farmers and drinking water to a lot of people. This is one more blow to a part of the state hit hardest by California's three years of drought.

The groundwater is supposed to be protected by state and federal laws, including the U.S. Safe Drinking Water Act, from contamination. The State Water Resources Control Board told the U.S. Environmental Protection Agency (EPA) in a letter (pdf) that high concentrations of thallium, arsenic and nitrate were found in water wells near the disposal wells.

Thallium is used in rat poison and arsenic is notoriously poisonous.  It has been linked to cancer, heart disease, stroke, respiratory diseases and diabetes. “The fact that high concentrations are showing up in multiple water wells close to wastewater injection sites raises major concerns about the health and safety of nearby residents,”  Timothy Krantz, a professor of environmental studies at the University of Redlands, told the Center. 

Fracking uses high volumes of water, sometimes as much as 150,000 gallons, to blast sand, chemicals and other materials into wells to reach deposits otherwise out of reach. Most, but not all of that material, comes back out of the ground and is injected into  separate wastewater wells. California has an estimated 1,552 active injection wells out of a total of 2,583 statewide, according to Clean Technica.

The nine wells were among 11 in Kern County shut down in July by the state Division of Oil, Gas and Geothermal Resources (DOGGR) just days before it was announced that 95 other wells were also being looked at.  The two others re-opened almost immediately.

A ProPublica investigation in 2012 found that 700,000 injection wells across the country were poorly regulated and many were likely polluting aquifers. It found around 1,000 exempt aquifers, many of them in California.

–Ken Broder

To Learn More:

Fracking Wastewater Spoils California Drinking, Farm Supplies (by Sandy Dechert, Clean Technica)

Frackers Are Dumping Toxic Waste into California’s Groundwater (by Madeleine Thomas, Grist)

Documents Reveal Billions of Gallons of Oil Industry Wastewater Illegally Injected

into Central California Aquifers (Center for Biological Diversity)

Well Tests Find No Contamination from Waste Injections (by John Cox, The Bakersfield Californian)

State Shuts Down Fracking Waste Injection Sites as Possible Threats to Aquifers (by Ken Broder, AllGov California)

Letter: Underground Injection Control Drinking Water Source Evaluation (by Jonathan Bishop, U.S. Environmental Protection Agency)