Center for Biological Diversity

For Immediate Release, January 12, 2017

Contact: Patrick Sullivan, (415) 517-9364,

California Agency Proposes Turning Monterey Aquifer Into Oil Waste Dump

State's Proposal Shrugs Off Voters' Approval of Ban on Oil Waste Injection

SAN ARDO, Calif.— Just months after Monterey County voters approved a ban on underground injection of oil waste, California regulators have announced a plan to turn an underground water supply in the county over to the oil industry for injection of contaminated waste fluid. 

“This a slap in the face to Monterey County residents who voted to protect water supplies from oil waste,” said Hollin Kretzmann of the Center for Biological Diversity. “State regulators are ignoring the will of the people and endangering their water by supporting this outrageous plan to turn this aquifer over to the oil industry.”

The proposal — announced Wednesday afternoon by California's Division of Oil, Gas and Geothermal Resources — seeks to exempt an aquifer that runs under the town of San Ardo from the federal Safe Drinking Water Act.

If approved by the incoming Trump administration, this "aquifer exemption" could lead to water contamination, greater risk of oil industry-induced earthquakes and increased crude production from one of California's most carbon-intensive oilfields.

In November Monterey County voters passed Measure Z, a ballot initiative that bans fracking, prohibits drilling new oil wells, and phases out existing wastewater disposal wells. The measure won with more than 56 percent of the vote, despite supporters being outspent 30 to one by oil companies.

Water contamination was a key concern in the election. Yet the state's aquifer exemption application fails to prove that injected oil waste will not migrate beyond the proposed exemption boundaries. That could contaminate nearby water sources.

The state's proposal also shrugs off the risk that new oil-industry injections could trigger manmade earthquakes. Scientists have already linked quakes in the San Ardo oilfield to oil-industry activities.

A 2009 U.S. Geological Survey report describes an earthquake cluster in San Ardo that was composed of 96 seismic events ranging up to magnitude 4.5. “Considering the lack of mapped faults, the northerly strike, and the active oilfield operations, these events more likely were caused by human activity rather than tectonic forces,” the USGS report concludes.

Oil-industry wastewater injection has been implicated in earthquakes in Oklahoma, Texas and California. Even minor tremors could endanger other nearby water supplies by opening up pathways to contamination.

State regulators' support of this aquifer exemption to facilitate increased oil production is also at odds with California's efforts to fight climate change.

Crude from the San Ardo oilfield is more climate damaging than any other large source of oil produced in, or imported into, California, according to a recent Center analysis of state data. The Center's report, titled Stealing California's Future, found that San Ardo crude is even more carbon-intensive than notoriously dirty oil from the Alberta tar sands in Canada.

“Why is the Brown administration helping one of the state's dirtiest oilfields wiggle out of a federal law meant to protect our drinking water?” Kretzmann said. “In a state struggling with drought and climate change, this exemption application makes absolutely no sense.”

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.1 million members and online activists dedicated to the protection of endangered species and wild places.

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