Camp Pendleton is latest California agency to find PFAS chemical in drinking water

Camp Pendleton leaders on Monday sent a public notice to thousands of service members and civilians who live and work on the base’s north end alerting them that recent testing revealed their drinking water contained a higher-than-desired level of PFAS, a potentially carcinogenic chemical that has been found in much of Southern California’s groundwater supply.

PFAS, or per- and polyfluorinated substances, can be found in cleaning products, water-resistant fabrics, grease-resistant paper and non-stick cookware, as well as in products such as shampoo, dental floss and nail polish. The state only set requirements to test for the chemicals in the last few years and has lowered the threshold for when their detection needs to be reported to the public by water agencies.

Water districts throughout Southern California have been struggling to get PFAS levels down. Base officials believe their water supply was likely impacted by groundwater that seeped in from inland and uphill Orange County.

For example, of the roughly 200 wells managed by the Orange County Water District in the north and central parts of the county, 61 have had to be closed. A water treatment plant in Fullerton to remove PFAS contaminants went into service in 2021.

The letter sent by Brig. Gen. Jason Woodworth, the base commander, alerted about 18,000 people at the San Onofre housing area, where Marines live with their families, as well as the Fifth Marine Regiment and the School of Infantry that results on Feb. 14  from the base’s northern water treatment plant tested at 23.5 parts per trillion in the drinking water, which is higher than the reporting threshold the state’s Department of Drinking Water set in October at 20 parts per trillion.

One part per trillion is about the same as four grains of sugar in an Olympic-sized swimming pool.

The base is blending the water in several wells – one of the approved options for reducing PFAS levels – and are awaiting new testing results.

“The main point is to let folks know of the current condition and steps we’re taking to ensure safety,” Woodworth said. “We remain in compliance with all the guidelines.”

Base officials on Monday said they have taken steps to ensure that the water at the base’s north end is safe for drinking and said they are not recommending the community “go to household filtration at this time.”

“It shouldn’t be in the water, but it’s not something that is acutely dangerous,” said Navy Cmdr. Stephen Ramsey, an engineer who is in Public Works on the base. “If it’s acutely dangerous, you shut the water system down, but this is not the case.”

Camp Pendleton operates mainly with two water systems, one serving its south end and one on the north end. There is a smaller system that supplies water to the Las Pulgas area of the base, but that’s not affected. The only water system presently impacted is the one on the north end, which produces about 1.2 million gallons a day.

Ramsey said back in October, after the state’s guidelines were issued to monitor for specific PFAS levels, officials checked all their wells. Five of the wells showed high levels, and those were immediately taken offline, he said.

Three more wells on the north end continued to be in use and in January, there was a pump failure in one of the three wells used to dilute the water.

“That’s when our blending was no longer clean enough to stay under the guidelines,” Ramsey said. “Two of the wells were significantly below the numbers and one was above.”