In a preliminary review of the state’s thousands of oil production and oil wastewater wells, the California Division of Oil, Gas & Geothermal Resources this year identified 2,553 wells that it suspected had been inadvertently allowed to inject into federally protected aquifers. After further review, the agency removed some injection wells from its risk category because they were abandoned, plugged or properly permitted. The agency has also shutdown 23 wells since it released this data. The agency is continuing to investigate the wells and says protecting water quality is its highest priority.
532 wells that pump oilfield wastewater into the ground
2,021 wells that produce oil
Sources: California Division of Oil, Gas & Geothermal Resources, U.S. Geological Survey. Graphics reporting by Doug Smith and Julie Cart
Len DeGroot and Lou Spirito @latimesgraphics