The U.S. Navy is requesting permission to sample water obtained from drinking water wells located within the sampling areas near Outlying Landing Field (OLF) Coupeville at Naval Air Station Whidbey Island to test for certain per- and polyfluoroalkyl substances, commonly known as PFAS.
Property owners with drinking water wells located in the sampling areas may request sampling by leaving a message at 1-844-WHI-PFAS (1-844-944-7327), or by sending an email to naswi.pfas@jacobs.com. Please include your name, property address, and phone number.
If your drinking water is provided by a public water provider in the sampling area, the Navy has already sampled or offered to sample their water and does not need to sample at your individual property.
Introduction
Per- and polyfluoroalkyl substances (PFAS) are a family of thousands of different chemicals which have been widely used in industrial and consumer products since the 1950s. PFAS are man-made and have been used in many household and industrial products because of their stain- and water-repellent properties. PFAS are now present virtually everywhere in the world. The Navy and Department of Defense (DoD) have developed policies to address past releases of PFAS at installations nationwide.
The most common activity that could have resulted in the historical release of PFAS to the environment at OLF Coupeville (Figure 1) is the use of firefighting foam (specifically, aqueous film-forming foam, or AFFF) for testing, training, firefighting, and other life-saving emergency responses. Because of this historical use, PFAS are present in the groundwater at OLF Coupeville and have been detected in nearby off-base drinking water wells in the direction that the groundwater flows away the base.
On April 26, 2024, the U.S. Environmental Protection Agency (EPA) issued a final National Primary Drinking Water Regulation (NPDWR) establishing nationwide drinking water standards for certain PFAS under the Safe Drinking Water Act. The regulation applies to public drinking water systems. Operators of public drinking water systems regulated by the NPDWR have five years to meet these standards. In September 2024, DoD published “Prioritization of Department of Defense Cleanup Actions to Implement the Federal Drinking Water Standards for Per- and Polyfluoroalkyl Substances under the Defense Environmental Restoration Program,” which describes DoD’s plans to incorporate the EPA’s drinking water regulation into DoD’s ongoing PFAS cleanups and prioritize interim actions to address private drinking water wells with the highest levels of PFAS from DoD activities.
Table 1 presents the DoD PFAS interim action levels for private drinking water wells. the DoD’s September 2024 memorandum can be found here. To learn more about the DoD’s September 2024 memorandum, the November 19, 2024, DoD PFAS Outreach Event can be found here.
The Navy continues to follow the policy it issued in June 2016 to conduct investigations at installations where there has been a known or suspected release of PFAS to the environment. The policy can be found here.
Private Drinking Water Well Sampling Near OLF Coupeville
Certain PFAS have been detected in groundwater near OLF Coupeville above the DoD PFAS interim action levels for private drinking water wells (Figure 1). As a result, multiple sampling areas have been established in the direction that groundwater flows away from the locations of these detections. The Navy continues to offer sampling to all property owners whose property is within the sampling areas (Figure 1) and whose drinking water is supplied by a drinking water well.
Figure 1: OLF Coupeville Sampling Areas

The Navy is requesting permission to sample certain drinking water wells located in the sampling areas shown on Figure 1. The Navy has also determined that certain drinking water wells sampled between 2016 and 2020 should be resampled because the laboratory method at that time could not detect PFAS at the current lower levels. Because of the laboratory method limitations, PFAS previously reported as not detected may now be detectable at low levels in these drinking water wells. Records indicate that some properties within the sampling areas are provided drinking water by a public water system. If your drinking water is provided by a public water system, the Navy does not need to sample your drinking water. Property owners and tenants should contact their public water system with questions regarding its treatment and testing of drinking water.
Actions Based on Off-Base Drinking Water Sampling Results
The preliminary results from the private drinking water well sampling near OLF Coupeville are expected approximately 30 days after collecting the samples. The Navy provides notification to the property owners and tenants (if possible) of their drinking water results and any follow-up actions, if needed.
The Navy will provide bottled water for drinking and cooking to property owners or tenants in the sampling areas whose drinking water well contains PFOA and/or PFOS, individually or combined, above 70 parts per trillion (ppt) and will continue to provide bottled water until an enduring solution is implemented. If the Navy samples your drinking water well, and PFAS in your drinking water well are at or above the DoD PFAS interim action levels for private drinking water wells, the Navy, after consultation and approval from the property owner, will provide an enduring solution, such as a treatment system or connection to public water supply, as soon as possible.
2016 - 2025 Off-Base Drinking Water Well Sampling Near OLF Coupeville
From 2016 through 2024, the Navy sampled 123 drinking water wells near OLF Coupeville based on information available about potential PFAS releases. PFOA and/or PFOS were detected in nine drinking water wells above 70 parts per trillion (ppt), the DoD PFAS interim action level at the time. In 2020, the Navy added PFAS treatment to the Town of Coupeville’s water system (which addressed an exceedance in one supply well) and connected seven properties served by five wells to the Town of Coupeville water system. The Navy will continue to provide bottled water for drinking and cooking or a kitchen sink filtration system to the remaining four properties served by three wells with detections of PFOA and/or PFOS above 70 ppt until an enduring solution can be implemented.
Since 2017, the Navy has monitored drinking water wells in the sampling areas. Twice per year, the Navy samples drinking water wells with prior PFAS detections and drinking water wells next to properties with PFOA and/or PFOS above 70 ppt, the DoD’s previous interim action level.
Drinking water well sampling was conducted again in early 2025, the sampling included new wells and many resampled wells. During this sampling, there were no detections at or above the DoD PFAS interim action levels for private drinking water wells. To date, 145 wells have been sampled near OLF Coupeville (Table 2) including the 123 wells that were sampled from 2016 through 2024. Table 3 presents the PFAS results.


Identification of PFAS Releases at OLF Coupeville
A PFAS Preliminary Assessment (PA) was finalized in 2018 that identified three areas where releases of PFAS may have occurred at OLF Coupeville. Several phases of a Site Inspection (SI) have occurred at OLF Coupeville from 2017-2020. Subsequent SI Reports were finalized in May 2018, September 2018, October 2021, and January 2022. Based on the SI results, a Remedial Investigation started in 2020 and is underway.
The PFAS release areas investigated at OLF Coupeville are depicted on Figure 2; Table 4 lists the release areas investigated during the SI and RI along with the current status. The Navy will continue on-base PFAS investigations following the CERCLA process and evaluate if additional actions are needed. All final documents are posted to the Navy’s CERCLA Administrative Record available at https://go.usa.gov/xh2Rd.
Figure 2: OLF Coupeville PFAS Release Areas

