EPA Superfund Site

NAVAL AIR STATION, WHIDBEY ISLAND (AULT FIELD)

WA | EPA ID WA5170090059

About this site’s exposure pathways: As of July 2024, the Naval Air Station Whidbey Island Superfund site is considered “Current Human Exposure Not Under Control”. The Navy is investigating the nature and extent of per- and polyfluoroalkyl substances
(PFAS) contamination in groundwater. The known source of PFAS is Aqueous Film Forming Foam released during on site and infiltrating into the groundwater. Off-base residential wells had PFAS detections over the Lifetime Health Advisory (LHA) of 70 parts per trillion (ppt), far above the 4 ppt Maximum Contaminant Level (MCL) for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). Potential and/or actual PFAS exposures above the MCLs are known to be occurring in this area. This exposure pathway is considered unacceptable based on EPA risk-based criteria because affected residents between the MCL and LHA have not been provided treatment systems or bottled water.
Currently, the planned activities to address this pathway are to complete the Remedial Investigation and determine an appropriate clean up remedy in a Record of Decision. Currently, time-critical removal actions (TCRA) are underway for residences above the LHA. If you are impacted by risks inherent at this site, contact the Navy Remedial Project Manager for more information. EPA and the Navy currently anticipates that human exposure will be under control by January 2030. By this time the Record of Decision for the PFAS operational unit is expected to be completed, and the Remedial Actions will be implemented.
In addition, the Navy is currently planning on providing drinking water treatment systems to residents with PFAS concentrations 3 times the MCL until the Record of Decision is complete. The Navy will continue to host multiple PFAS information sessions each year and sampling efforts that step out half a mile from previous positively tested wells above the MCL. The EPA and other local agencies attend these sessions and are available to answer community questions.