The Navy has agreed to install a filtering system in the Town of Coupeville’s water system to lower the level of a chemical that comes from a type of firefighting foam.

The granulated activated carbon system will remove per- and polyfluoroakyl substances, known as PFAS, from the town’s drinking water.

The Navy will also connect 10 families outside of town limits with contaminated wells to the Coupeville system, Navy officials reported.

Kendra Leibman, remedial project manager with Navy Facilities Engineering Command, said that the filtering system will lower the level of the chemical in the water, not remove it entirely. Details of the filtering system’s design aren’t finalized, she said.

Coupeville Mayor Molly Hughes reports that the project won’t cost ratepayers anything.

The Navy will pay for the system and annual operation, she wrote.

“They are voluntarily adding treatment to our public water system, at no cost to our water customers, even though currently, there are no state or national mandatory regulations pertaining to PFAS compounds,” she wrote.

“They have been a conscientious neighbor, wanting to do the right thing in this unfortunate situation.”

Two years ago, the Environmental Protection Agency set a lifetime health advisory level for perfluorooctanoic acid, or PFOA, and perfluorooctane sulfonate, or PFOS, at 70 parts per trillion. The chemicals are considered “emerging contaminants” with possible health effects.

The Navy tested private wells surrounding Naval Air Station Whidbey Island’s Ault Field and Outlying Field Coupeville; eight wells serving 10 families near OLF Coupeville were found to have water with levels above the advisory level.

The town’s independent testing of the municipal water system found PFOA levels of 62 and 59 parts per trillion in two samples taken at its Keystone well.

Neither of the chemicals were detected in three wells at Fort Casey.

The town also tested the water at the entry point of the distribution system, which is after the water from all four wells is blended.

Two samples showed PFOA levels at 25 ppt and 27 ppt.

The Town of Coupeville, however, plans to increase the amount of water pumped from the Keystone well, which would likely increase the level of PFOA in the blended water that goes to customers.

Leibman said the increase in Keystone well usage was one factor considered when making the decision to install a filtering system. She said officials also wanted to “maintain protectiveness” in case the levels of the chemicals increase or the advisory level decreases in the future.

The system will be designed by CH2M, a nationally recognized engineering firm, Hughes wrote.

Leibman said the Navy evaluated options for providing permanent sources of clean water for rural residents with contaminated wells.

The Navy provided families with bottled water since the results came back last year. Connecting the rural residents to the town’s water system was chosen as the best option, she said.

Those involved in the discussion included officials from the Navy, town, Island County Public Health, state Ecology, the Agency for Toxic Substances and Disease Registry and the Environmental Protection Agency.

Greenbank resident Richard Abraham has repeatedly urged officials at WhidbeyHealth Medical Center to install a filtering system at the hospital, located in Coupeville and on town water.

Abraham pointed out that the school system is also on town water.

“It’s not just about the Town of Coupeville,” he said.

Abraham has also tried to get the results of the Navy’s latest tests, which looked for the presence of 14 different PFAS chemicals.

Leibman confirmed that the Navy has the results, but said she isn’t authorized to release them. They were shared with affected rural homeowners, but not town residents.

Leibman said the timeline for installing the filtering system and connection of the rural houses hasn’t been determined.

After that work is complete, she said, the Navy will work to delineate the extent of the chemical plume at OLF Coupeville.