Fort Knox, Ky. – Initial results from DoD-mandated Per- and Polyfluoroalkyl Substance, or PFAS, testing at seven locations here conducted earlier this year shows minimal environmental contamination.
The Environmental Protection Agency defines PFAS as a group of about 600 man-made chemicals that have been manufactured and used in a variety of industries around the world, including in the United States since the 1940s. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) have been the most extensively produced and studied of these chemicals. Both are persistent in the environment and in the human body – meaning they don’t break down and can accumulate over time.
These chemicals are found in a number of everyday household items, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints and cleaning products.
In May 2016, the EPA also set a lifetime health advisory level for PFAS in drinking water of 70 parts per trillion. While this is not currently an enforceable standard, it sets a guideline for municipalities to follow.
In June 2016, the DoD proactively mandated the testing of more than 400 military installations in an effort to discover and mitigate any potential risk to humans and the environment.
In February 2020, the EPA announced a proposed decision to regulate PFOS and PFOA in drinking water throughout the United States.
The past release of PFAS chemicals here stems from the Fort Knox Fire Department’s use of Aqueous Film Forming Foam, or AFFF, in past training exercises and aircraft/fuel firefighting applications. Seven sites of known AFFF release were chosen for evaluation here, five of which are at Godman Army Airfield, where the foam was stored and used in training exercises. PFAS in the ground water/soil at the other two testing sites was either non-detectable or well below the EPA lifetime health advisory level.
Testing conducted in the area in and around the airfield training location predictably showed slightly elevated levels of PFAS chemicals in the soil and surface water within drainage areas in the immediate vicinity of the site.
According to Fort Knox Environmental Management Division Chief Dan Musel, though traces of PFAS chemicals were found, the results at the airfield testing site do not indicate contamination of on- or off-post drinking water supplies or pose a risk to human beings.
“The test results do not show impacts to area drinking water. In fact, Fort Knox typically draws most its drinking water from locations far away from the airfield at wells located near the Ohio River,” Musel said. “Fort Knox’s finished drinking water, meaning water coming out of the treatment plants that supply the installation, was sampled in 2013 and again in 2019 and PFOS/PFOA were not detected.”
Musel added that Fort Knox is presently receiving its finished drinking water from other off-post Hardin County Water District #1 sources while the Muldraugh Water Treatment Plant – normally the primary source of Fort Knox’s water supply – undergoes renovations.
Fort Knox Fire Department Chief Jay Schiedewitz said AFFF is an important part of aircraft and fuel firefighting that’s still used by military installations and civilian fire departments alike.
“AFFF is currently the only proven and effective tool at our disposal for extinguishing fuel and aircraft fires and it is still the only DoD-approved chemical for that purpose,” Schiedewitz said. “It saves lives.”
Fort Knox now uses an updated version of the chemical.
“The version of AFFF that we’re using now is considered to be much less toxic than the version previously used,” said Schiedewitz. “DoD is working to find a fluorine-free alternative, but so far, an acceptable substitute has not been found.”
Schiediwitz said that the FKFD ceased training with AFFF in 2016 following an Army-wide mandate citing the chemical’s potential health and environmental impacts. It is now used only in emergency situations, and environmental cleanup efforts are conducted immediately following its use.
Musel said that while the recent test results are promising, officials will continue to evaluate airfield sites.
“We are currently working to conduct more extensive testing in the area,” Musel said. “Ensuring minimal environmental impact and the safety of the on and off-post communities is a top priority for us.”
Note: When testing is complete, the Army will publish a report that will be available to the community.