Cargill’s ponds at center of multimillion-dollar Bay Area pipeline proposal for long-term environmental solution

NEWARK, Calif. (KGO) — From above, Cargill’s salt ponds in southern San Francisco Bay look like a giant checkerboard. A criss-crossing of dykes, transforming evaporating seawater into mountains of high-quality salt. But recently, several environmental groups raised concerns about the materials in two of those ponds.

There remains concentrated bittern from the salt-making process, which they say could pose a threat to nearby wildlife, if released.

“Agencies need to get out and inspect these ponds and make sure we’re not on the brink of a catastrophic toxic spill in San Francisco Bay,” said David Lewis, executive director of Save the Bay.

The group recently co-wrote a letter to the San Francisco Bay Area Conservation and Development Commission, asking if the agency is effectively monitoring the ponds and surrounding levees maintained by Cargill. Among their concerns are threats to the levees from rising sea levels, king tides or a strong earthquake – and the possibility of a spill or seepage reaching the nearby Don.

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“There are toxic sites all around the edge of the bay that are much more heavily regulated. It’s disconcerting that agencies haven’t taken a stronger stance to protect the bay from these toxic materials,” Lewis said.

The concerns come as Cargill rolls out a major proposal that could transform how the company stores and processes bittern, also known as blended sea salts. It’s a plan that would end up throwing them back into the bay.

Don Brown is Cargill’s Land Resources Manager. He says the company wants to build a multimillion-dollar pipeline project designed to be a long-term solution.

“We understand that sea level rise and climate change are coming. And we realize it is time to act. So we are taking a proactive approach to protect the bay by improving the treatment of these mixed sea salts” , Brown said.

The pipeline would run about 16 miles from Cargill’s ponds near Newark to the sewage treatment system run by the East Bay Dischargers Authority. After the brine is mixed with the treated wastewater and diluted, it would be piped to this facility in San Leandro and discharged into the bay.

Chief Executive Jackie Zipkin said the project will be one of the biggest additions to East Bay’s sewer system in years. And she thinks the dilution process is a surefire way to get rid of bittern.

“We see it as our mission to protect the bay. demonstrate that the combined effluent and brine from Cargill would be safe for the bay, it meets all of our permit limits,” Zipkin says.

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The environmental impact report is still under study. If approved, the pipeline would be owned and built by Cargill. Eileen White is executive director of the San Francisco Regional Water Quality Council. While acknowledging that her agency did not specifically inspect the two ponds, she says Cargill provided a recent inspection report that included aerial photographs of the site. She also supports the pipeline plan.

“So it’s sort of a return. It comes from the bay, you send it back into the bay, but not at such a high concentration that it could be toxic to the environment,” White says.

Yet groups like Save the Bay say it could be years before construction is complete. And they cite recent levee failures like the breach in Monterey County as an example of the increased risk. And in the meantime, they’re pushing for increased monitoring by agencies like the Bay Conservation and Development Commission and the Regional Water Quality Control Board.

“There’s a lot of letters going back and forth between the agencies and the company, it’s not enough. They need to go out and inspect this site and see how close the material is to the top of the ponds,” Lewis says .

An exercise in environmental balance in a corner of San Francisco Bay that is both the center of a thriving industry and home to a fragile and majestic wildlife refuge.

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