A person walks past pump jacks operating at the Kern River Oil Field in Bakersfield, Calif. (AP Photo/Jae C. Hong)
David R. Baker of the San Francisco Chronicle newspaper reports California regulators on Thursday closed 33 oil company wells that had injected wastewater into potentially drinkable aquifers protected by federal law.
The new closures bring to 56 the number of oil-field wastewater injection wells shut down by the state after officials realized they were pumping oil-tainted water into aquifers that potentially could be used for drinking or irrigation.
All but two of the latest closures are in Kern County, in California’s drought-stricken Central Valley. One lies in Ventura County, another in northern Los Angeles County. Officials with California’s Division of Oil, Gas and Geothermal Resources spent Friday verifying that they had, in fact, closed. Of the 33, only 21 had been actively injecting wastewater before Thursday.
“This is part of our ongoing effort to ensure that California’s groundwater resources are protected as oil and gas production take place,” said Steven Bohlen, the division’s supervisor.
California’s oil fields contain large amounts of salty water that comes to the surface mixed with the oil. It must be separated from the petroleum and disposed of, often by injecting it back underground. Much of the water is pumped back into the same geologic formation it came from. But enough left-over water remains that companies must find other places to put it.