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Aera Energy
 (Aera Energy)

How Much Drinking Water Has California Lost to Oil Industry Waste? No One Knows

How Much Drinking Water Has California Lost to Oil Industry Waste? No One Knows

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California survived its historic drought, in large part by using groundwater. It was a lifeline in the Central Valley, where it was the only source of water for many farmers.

California regulators are charged with protecting that groundwater, but for years they failed to do so. Through a series of mistakes and miscommunication, they allowed oil companies to put wastewater into drinking water aquifers that were supposed to be safeguarded.

Now, a KQED investigation reveals that regulators still know little about the actual impact on the state’s groundwater reserves.

One of those errors was discovered by an unlikely person: Bill Samarin, a farmer in California’s San Joaquin Valley.

Oil and agriculture are the big employers in Tulare County, where Samarin lives. Among the citrus and almond orchards, you see steel pumpjacks bobbing above the treetops. So criticizing either of those industries doesn’t make you popular.


“That doesn’t set well with people around here,” Samarin said. “You’re some kind of environmentalist, which isn’t a very accepted thing to be if you’re a farmer out in this area.”

Samarin is not an environmentalist. He describes himself as a “pretty conservative guy.” So what he discovered about the oil industry put him in unfamiliar territory, straining relationships in this tight-knit community.

The Biggest Issue

It started with the oil field not far from his orchard.

“From our house, we could look across and it’s probably about three-quarters of a mile,” he said.

County officials had received an application to expand that oil field and allow more drilling. Given how close it was to his property, Samarin started doing some homework.

“When I looked into it further, I found out actually that the biggest issue out here isn’t the things you see on top of the ground,” he said. “The biggest issue out here is the wastewater and how they’re getting rid of it.”

Oil companies in California produce tons of wastewater. On average, for every barrel of oil, a California oil well produces 19 barrels of water, often laden with salts, trace metals and chemicals like benzene.

“They have to get rid of it somehow and in this area here, they pump it into the ground,” he said.

It’s the standard way in which oil companies dispose of wastewater in California: using injection wells, which are not much more than a pipe going into the ground with a gauge to monitor water pressure.

Generally, the wastewater is deposited pretty deep, below the usable groundwater, into aquifers that are already too salty to be drinkable.

Samarin decided to look up all the wells near his orchard, to see where the wastewater was going. He couldn’t believe what he found.

“I was just stunned, stunned by how close it was to groundwater,” Samarin said. He uses groundwater on his crops, along with a lot of other farmers in the area.

“I just drilled a well here,” he said. “We drilled down to 740 feet. The injection wells in this area are injecting at similar depths.”

Alarmed, Samarin went to the local water regulators, the Central Valley Regional Water Quality Control Board. They told him how a water law, known as the Safe Drinking Water Act, works. Groundwater that’s potentially drinkable is automatically off limits for oil companies for wastewater disposal.

But if groundwater quality is already tainted by oil or salts, then companies can get permission from state agencies and the federal Environmental Protection Agency to put wastewater there.

The regulators gave Samarin a map of the land around his orchard that had been approved for wastewater disposal, as well as the areas that were protected.

Most people probably would have stopped there, but not Samarin. He wanted to know how close those injection wells were to his protected aquifer.

Digging Through the Maps

Samarin didn’t have to turn very far for help. His son, Alex, works with maps for a living.

“I think we’re both curious people,” said the younger Samarin. “Once the question is asked, we want to see what the answer is.”

He plotted coordinates for all the wastewater wells on top of the land approved for wastewater.

“Six out of the seven did fall within the allowable aquifer,” he said. “One was completely outside of it.”

That meant an oil company was putting its wastewater into a protected aquifer that was supposed to be off-limits.

“We were just stunned,” recalls Bill. “It was like: is this even possible that they could be taking wastewater and injecting it into drinking water? Can you imagine that that actually occurs in California in this day and age?”

A wastewater injection well in San Joaquin County. (Lauren Sommer/KQED)

He decided to take it to county officials.

In 2014, Tulare County held hearings about whether to allow the oil operation near Samarin’s orchard to expand, and he filed an appeal against it.

He wanted the county to know about the mistake: that regulators with the state’s Division of Oil, Gas, and Geothermal Resources had permitted a wastewater well that it shouldn’t have. Over a decade, it had pumped 80 million gallons of wastewater into the aquifer.

At the hearing, Samarin presented his report, going over everything he and his son had found.

“Produced water associated with oil production can contain many constituents that may endanger the environment or the public health,” he testified.

When the meeting was opened for comments, Burton Ellison, a recently-retired regulator with DOGGR, challenged Samarin’s findings, calling them untrue. “Every one of those wells went through a rigorous review,” Ellison told the hearing. “As a matter of fact, I reviewed some of them back in 2008.”

In the end, county supervisors denied Samarin’s appeal, stating that regulating wastewater was the state’s job, not theirs.

Samarin let it drop for the time being. “I left it to other contacts,” he said. “The state water board knew about it.”

Six months later, those state water regulators reviewing wastewater wells discovered that Samarin had been right.

They ordered the errant injection well that Samarin had found be shut down. The oil company, Modus, Inc., responded that its wastewater didn’t contaminate the aquifer because it had the same salt level as the aquifer it was going into.

What Samarin didn’t know was that his wasn’t an isolated case. It was happening all over California.

“Broken System”

“There are thousands of wells spread all across the state that are potentially impacting clean drinking water,” says Briana Mordick of the Natural Resources Defense Council.

State oil regulators grant permits for wastewater injection wells, so knowing the boundaries between protected and unprotected aquifers is crucial. But for decades, Mordick says, state regulators confused those boundaries.

“It’s just a pretty shocking state of affairs,” says Mordick. “Just poor communication, poor record-keeping. It looks like a completely broken system.”

“Our records weren’t solid,” admits Teresa Schilling, a spokesperson for the division of oil and gas. “They were missing in many cases and it’s essential that we have accurate records.”

In some cases, the aquifer maps were decades old with fuzzy boundaries. In other cases, the records regulators used to make decisions were mixed up 30 years ago. The Environmental Protection Agency had a complete list of the protected aquifers, but for unknown reasons, California oil regulators were working from an incomplete list that didn’t include 11 protected aquifers.

“We understand that the public has concern about what’s at stake with their drinking water,” says Schilling. “We all know we have a right to clean drinking water and we have a right to expect that our government will take care of that for us.”

What regulators are doing now, Schilling says, is reviewing records for thousands of wastewater injection wells, looking for mistakes. So far, about 175 wells have been shut down.

But six years after the problems emerged, there are still hundreds of wastewater wells operating in protected aquifers, mostly in Kern and Tulare counties. Schilling says these aquifers aren’t drinking-water quality and the state is going through the process of approving them for wastewater disposal. That was supposed to happen by February, but the process is still unfinished.

“It’s very hard as a government entity to move fast but this has been a top priority at the Department of Conservation,” she says.

Minimal Testing

Still not fully understood is what impact all this has had on the quality of California’s drinking-water aquifers.

“The testing that has been performed has been minimal, I would say,” says John Borkovich of the State Water Resources Control Board.

The agency has tested some of the drinking water wells within a mile of the wastewater wells that were wrongly permitted. The tests looked at the quality of the drinking water.

Borkovich says officials have found no correlation between wastewater injection and “anything we’re finding in the water supply wells.” So far.

“Just because we haven’t seen anything, doesn’t mean there isn’t an issue out there,” he said.

The next, bigger challenge is determining what the long-term impact of wastewater has been on the larger aquifers. Some wastewater wells have been operating for decades.

KQED asked oil regulators for records showing contamination levels of the wastewater that oil companies put into the cleanest aquifers. Officials say they can’t produce those records for KQED, because the information is in stacks of paperwork, spread across several regional offices. They also say the division of oil and gas isn’t looking at that question.

Given how far back the permitting problems go, it could be a challenge for the state to reconstruct what’s happened underground.

“We don’t necessarily have good records of what the quality of that water would have been 20 years ago when they started doing this,” said NRDC’s Mordick. “So trying to figure out whether their actions have impacted the water is really difficult at this point.”

Mordick adds that the state may be overlooking certain chemicals in their testing.

“One of the complicating things is that the state doesn’t require disclosure of most of the stuff that oil and gas operators use,” Mordick says. “Things like drilling fluids, or maintenance fluids, enhanced oil recovery operations, so really, we wouldn’t know what to test for.”

The aquifers in question may not contain groundwater that California needs right now, but future droughts are inevitable.

“Those resources are becoming more and more valuable over time,” says Mordick. “Protecting our groundwater is really important. They need to follow the rules and California needs to step up and take this seriously because they haven’t been for a long time.”


State water regulators say they hope to figure out what the larger impacts have been in the years ahead, but have no set timeline. The risk is that they’ve allowed oil companies to contaminate drinking water aquifers to such an extent that Californians may have permanently lost those sources of fresh water.

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