Nearly 30 public water systems in California, including one in the East Bay, have found chemicals in drinking water that have been linked to toxic firefighting foam. The detections came to light after a federal requirement forced large public water systems to test drinking water for perfluorinated compounds, or PFCs.
While the Environmental Protection Agency does not regulate the chemicals in drinking water, the agency classified them as “emerging contaminants” that require ongoing monitoring. EPA officials have spent considerable time in recent years trying to better understand PFCs, but some critics argue the agency has not moved quickly enough to set appropriate health provisions.
The compounds were historically used in the making of Teflon, Scotchgard and hundreds of other household products. Because the chemicals are resistant to heat, water and oil, PFCs were also used to make foam firefighters spray on airplanes during crash landings.
Local municipalities including the San Jose and San Francisco Fire Departments say they now use environmentally friendly foam. But across the county for decades, foam with toxic PFCs was used at airports, refineries and at military bases, where crews conducted fire and crash training. Now, the government is concerned that the chemicals may have spread into our nation’s water supply.
The EPA required all large public water systems in the country to test for PFCs from 2013 through 2015. The Investigative Unit analyzed the results and found nearly 200 water systems across the country detected the chemicals at levels above the EPA’s testing limit. Twenty eight water supplies in California found PFCs, more than any other state in the nation.
See which cities found elevated levels of PFCs, the location of the state’s airports and the groundwater basins in California in the map above.
One drinking water well in Pleasanton tested positive in November 2013 and again in June 2014 for a PFC linked to firefighting foam. City officials said the detection could have come from the water in the well at the time or an existing plume that had trace amounts of the chemical.
Dan Martin, the city’s utilities superintendent, said the contamination was found at low levels, just above the testing threshold. But the detection surprised him.
“When we collect these samples our hope and expectation is that there won’t be any contamination in it,” Martin said.
He said the well is located in an area that was historically used for agriculture, not industrial manufacturing. With no airport nearby, Martin said the source is a mystery.
Martin said residents should have confidence that their drinking water is safe. He said the city’s normal process entails blending water from two different wells before distributing it through the system. He also pointed out that a positive hit for a chemical doesn’t necessarily mean that is poses a danger to the public.
“We do not feel like this particular contaminant, at levels it was detected at, is something that is an imminent health risk,” Martin said.
After the Investigative Unit started asking questions about the detections, the city conducted an additional round of testing. On May 17, the results came back clean.
In an email, city spokeswoman Tracy Dunn said officials are “very pleased with the most recent findings” and that the city will continue to monitor its drinking water wells.
Manufactures stopped using one toxic PFC nearly 15 years ago and phased out another last year. But the chemicals have been described as virtually indestructible.
“It’s extraordinarily long-lived. Once it gets out in the environment it almost never breaks down,” said Bill Walker, head of the Bay Area office of the Environmental Working Group, a nonprofit that has studied PFCs for the past decade. “Its persistence, the fact it builds up in your blood and the fact it was so heavily used for so long, means it’s a big worldwide problem.”
Many PFCs have been liked to developmental delays, decreased fertility and changes to the immune system. The EPA is evaluating internal research that suggests some PFCs are likely carcinogenic to humans. Because of this, health experts, scientists and the military are becoming increasingly interested in whether PFCs are getting into the groundwater.
In 2014, researchers who work with the San Francisco Estuary Institute and the state’s Environmental Chemistry Lab found low levels of PFCs in eight wastewater treatment plants that discharge to the Bay. In a study published in March, they noted that detections in plants near San Francisco International Airport, and Travis Air Force Base, just outside of Fairfield, are likely related to the use of firefighting foam.
Late last year, the Department of Defense began testing groundwater for contamination around more than 650 military bases that historically trained with foam. Eighty five are in California, including Alameda Naval Air Station, Moffett Airfield in Silicon Valley and Treasure Island Naval Station in San Francisco.
85 sites on or near military bases in California where the Department of Defense is checking for PFOA and PFOS drinking water contamination.
Cities and water districts look to regulatory agencies for guidance on safe levels of contaminants in drinking water. Several states have issued their own drinking water standards for PFCs, but California is not one of them.
The EPA issued a provisional health advisory for PFCs in 2009. But the advisory is just a guide. The federal government does not regulate the chemicals in drinking water. The agency said it plans to release an updated health advisory before the summer. Officials said the water testing data will help the EPA decide whether it should develop a national drinking water standard.
“This EPA testing is a really good first step just to understand if PFCs are occurring and at what levels,” said Vanessa De La Piedra, Santa Clara Valley Water District’s groundwater manager.
She said regulatory agencies face the daunting task of evaluating and narrowing down which of the hundreds of contaminants that exist pose the greatest risk to the public.
“I think the EPA is definitely taking action to better understand these,” De La Piedra said.
However, Walker’s group questions just how detailed the EPA’s testing process really is, noting that some labs have the ability to detect PFCs at much more sensitive levels. He also points out that the EPA’s testing program leaves out nearly 15 percent of the nation’s population that gets its water from private wells.
“We’re very concerned that the testing program was not rigorous enough and they are going to look at their findings and say well, this is not a very serious problem,” Walker said. “In fact, if they looked harder, we believe they would find more contamination.”
If you have a tip for the Investigative Unit, email firstname.lastname@example.org or call 888-996-TIPS.