Two wells near Dover AFB have possible elevated PFOS/PFOA levels

DNREC, EPA told results from USAF sampling are not yet validated

Dover, Del. – The U.S. Air Force (USAF) and Dover Air Force Base (AFB) notified Delaware’s Department of Natural Resources and Environmental Control (DNREC) that preliminary (i.e., not yet validated) results show two wells on separate properties near the base have possible elevated levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). The preliminary results indicate concentrations above the U.S. Environmental Protection Agency’s lifetime health advisory for these substances of 70 parts per trillion (ppt).

The preliminary, unvalidated results for these two wells are in addition to validated detections of PFOS and PFOA for four wells announced in July 2019. The USAF continues to provide alternative water supply to those properties. The Delaware Division of Public Health (DPH) is working with DNREC, USAF, Dover AFB, and the owners of the affected wells to protect public health. The owners of the two wells, who each provide water to a single commercial business, have been notified and provided with bottled water by Dover AFB.

The unvalidated results of water samples recently collected by the USAF from ten other wells reported PFOS and PFOA below the federal health advisory level. Although the recent test results are unvalidated at this time, validation of the data is expected within 30 days.

PFOS and PFOA are part of a group of synthetic chemicals known as perfluoroalkyl substances (PFAS) used in a variety of products that over time have become widely distributed in the environment. These chemicals have been found at Dover AFB and other air bases and airports in firefighting foam. The USAF and EPA have been working with DNREC and DPH to determine the impacts of PFOS and PFOA on private wells in proximity to the base.

A USAF fact sheet about the Dover AFB PFOS and PFOA sampling published in spring 2019 indicated that groundwater samples collected in shallow monitoring wells on the base also showed levels of PFOS and PFOA above EPA’s 70 ppt health advisory.

No PFOS or PFOA have been detected in five nearby municipal water wells tested by Dover AFB’s water supplier, Tidewater Utilities. Tidewater sampled four on-base municipal supply wells and the off-base municipal supply well nearest the base. All these wells draw water from a deep, confined aquifer. There were no PFOS or PFOA detections in any of them.

The primary step necessary to protect the public’s health from exposure to PFOS and PFOA in drinking water is to use an alternate water source until a permanent solution can be determined, which may consist of treatment, connecting to a new system, or other solution. DPH encourages the impacted businesses, office building, and dwellings in the affected area to use the bottled water provided by the DAFB until a permanent solution is in place. Anyone with specific health concerns or questions about potential health impacts is encouraged to contact their primary care provider. General questions about the health effects from, and exposure to, PFAS can call DPH at 302-744-4546.

At this time, there is no federal or state required standard for PFAS substances in drinking water supplies, so actions taken are based on the federal lifetime health advisory level.

For more information, please contact:
436th Airlift Wing, Public Affairs
Cell Phone: 302-363-9006 or 302-677-3372.