(KPIX 5) — A coalition of environmental groups is calling for a moratorium on new permits for irrigation of food crops with oilfield wastewater.

California Resources Corporation, one of the biggest oil producers in the country, just started selling its wastewater to the local water district last year. It’s blended with water in the canal and sent out to farmers.

Chevron has been running a similar operation just a few miles away with a different water district for more than 20 years, irrigating farmland where some of the country’s biggest food producers grow their crops.

California has strict regulations for recycling wastewater from buildings. But we’ve discovered the state has no regulations for using oilfield wastewater, even though it’s being used to water our food crops.

Yet, a KPIX 5 investigation reveals the practice is spreading, from one water district a year ago, to two, with a third district well into the permitting process.

The Kern Tulare Water district submitted a draft environmental impact report in May, and the comment period has now passed. “It’s a time for really close scrutiny,” said Adam Scow, the California Director for Food and Water Watch. “We think it is grossly, highly irresponsible to allow oil wastewater to be used on more and more of our crops,” he said.

While there are no state regulations for the use of oilfield wastewater for irrigation, the Central Valley Regional Water Quality Control Board does issue permits to the oil companies and the water districts involved. The so-called “produced” water is filtered through walnut shells and booms to separate it from the oil and is tested on an annual basis for a certain number of compounds, according to permit guidelines. Chevron and California Resources Corporation have abided by their permits for produced water, with no violations.

A newly-formed panel of experts is finally looking into the safety of using oilfield produced water for irrigation. In April, a toxicologist presented test results that show almonds and grapes grown with oilfield water are safe to eat. But he’s getting paid by one of the very water districts that is benefitting from the practice. “Our government has not done its own transparent testing yet,” said Scow. “And that should happen immediately and this practice should be stopped until that process can be completed.”

KPIX 5 asked the state water board if it would consider holding off on approving the latest oilfield water project in the Kern Tulare water district until it’s proved to be safe. A spokesperson told us the agency had no comment.

The groups proposing a moratorium on permits for oilfield wastewater are: Environmental Working Group, Clean Water Action, Earthworks, Sierra Club, Citizens Coalition for a Safe Community, Grassroots Coalition, Center for Environmental Health, Center for Biological Diversity, Coastal Environmental Rights Foundation, Association of Irritated Residents, and Fresnans Against Fracking.