Wastewater Use On California Crops Raises Questions

Known as “produced water,” wastewater from oil production is being used to irrigate crops across 95,000 acres of California’s Central Valley, where many of the country’s fruits and vegetables are grown.

95,000 is not as much as it sounds, according to Epoch Times, when compared to the 9.6 million acres of farmland California irrigates every year.

“Some hail it as an innovative way to recycle the massive amounts of oil industry wastewater, while others have decried the practice, saying the human health effects have not yet been studied enough in depth.”

According to a report released in September by the PSE Healthy Energy research institute, “out of the 173 chemicals used in oil and gas fields that provide water for agriculture, as many as 66 remain undisclosed by oil companies, which classify them as ‘trade secrets.’”

What this all means is that there are a number of chemicals with unknown health impacts that have not been tested in the water itself and possibly in the crops grown with it. Even some of the chemicals that have been disclosed have “insufficient toxicology data to determine safe levels for human consumption.”

One of the report’s authors, Dr. William Stringfellow of the Lawrence Berkeley National Laboratory, is also part of an expert panel that was brought together by the Central Valley Regional Water Quality Control Board to evaluate the safety of this practice.

At a recent meeting of the panel in October, board members were “mostly positive about the use of the water, noting that studies done by toxicology firm Enviro-Tox  have shown only nine chemicals were absorbed by crops and only at low levels.”

Epoch reported that at the meeting, Stringfellow stated that even though the studies are encouraging, he identified 46 chemicals that could be of concern and should be further tested.

Dale Harvey, a supervising engineer for the board, told Epoch Times by email that the board’s legal counsel is working to figure out how “best to obtain information from the oil companies regarding the trade secret chemicals.”

“We are calling for a moratorium on the practice until it can be proven safe,” said Dr. John Fleming.

“Unfortunately, the water board is content to proceed with business as usual until it’s proven to be unsafe, which is irresponsible when we’re talking about our food supply and public health,” Fleming said.

Continued study on the use of the wastewater could help identify some health problems.

Fleming added that “wherever oil and agriculture share the same ground, this could be an issue. And how California handles it could set a precedent in similar regions, such as Texas.”

To read more about oil and gas wastewater visit Water Online’s Produced Water Treatment Solutions Center.