State regulators are scrutinizing more than 100 Kern County injection wells that if closed, as federal officials warn may be warranted, could force local oil companies to decide between cutting production and finding a new destination for several billion gallons of wastewater per year.
A few of the wells inject steam to aid in oil production, but the large majority dispose of “produced water” — the salty fluid that comes up from the ground along with crude oil — into aquifers whose historical exemptions from federal Safe Drinking Water Act protections were recently called into question by the U.S. Environmental Protection Agency.
The scrutiny is part of a wider crackdown on injection work in the state. It reflects EPA concerns California has not done enough to protect possible future sources of drinking water from potential contamination.
While local injection work has been under regulatory inspection since at least 2011, it was unclear how much oil field activity was on the line until the state turned over to The Californian last week a list of the wells that could be forced to close.
A decision is expected by the end of next year on whether to halt injections into as many as 11 California aquifers, eight of which are in Kern. Last month the EPA ordered state officials to test the aquifers’ water quality then determine whether to halt injections. The agency emphasized it will review any final decisions by the state.
State data show 108 Class II Underground Injection Control wells are permitted to inject into the eight local aquifers. Sixteen of these, or 15 percent, are classified as “idle,” while an additional seven wells are “new,” with no associated injection history. Some wells listed as “active” have not operated in recent years.
In all, the wells accounted for about 142 million barrels of produced water disposal in 2013, the most recent year for which complete data are available. That translates to about 6 billion gallons.