The Department of Defense (DoD) identified certain per- and polyfluoroalkyl substances (PFAS) as emerging contaminants of concern which affected
installations across the Air Force. When the term "Air Force" is used in this fact sheet, it includes Air National Guard. Specifically, perfluorooctane sulfonate
(PFOS), perfluorooctanoic acid (PFOA), and perfluorobutanesulfonic acid (PFBS) are components of legacy Aqueous Film Forming Foam (AFFF) that the Air
Force began using in the 1970s as a firefighting agent to extinguish petroleum fires. The U.S. Environmental Protection Agency (EPA) issued lifetime drinking
water Health Advisories (HA) for PFOS and PFOA, and health-based regional screening levels for PFBS.
The Air Force has systematically evaluated potential AFFF releases on all Installations and former Installations. It began with the Preliminary Assessments, or
PAs, that identified potential release areas. First responders, fire chiefs, and hangar staff were interviewed to determine where a release or a spill may have
occurred on an Installation (for example, aircraft crash site or an accidental hangar AFFF release). Once the information in the PA was collected, a Facility
Investigation (FI) was initiated, to take soil and water samples and analyzed the media for PFAS compounds at the potential release areas. The intention of the
FI was to determine if a release had occurred and to determine the impacts to soil and/or groundwater. The next step in the process is called the Relative Risk
Site Evaluation, or RRSE, which is a tool used to sequence Sites/Installations to begin a Remedial Investigation, or RI. Air Force Installations are at the
beginning of the more detailed investigative stage, the RI, to determine, where action is needed and to identify remedial technologies.
The Biddle ANG Base (Horsham AGS) PFAS PA and SI can be found at the Air Force CERCLA Administrative Record (AR): Scroll
to the bottom of the page and click on “Continue to site”, then select Air National Guard (e.g., Active, ANG, BRAC), scroll down the Installation List and click
on Biddle ANG Base (Horsham AGS), PA then enter the AR Number 467649 in the "AR #" field for the PA. For the FI, enter the AR Number 5574338. Then
click “Search” at the bottom of the page. Click on the spy glass to view the document.
More information on the Air Force response to PFOS and PFOA can be found at:

AFFF - Aqueous Film Forming Foam
AST – Aboveground Storage Tank
CERCLA - Comprehensive Environmental Response, Compensation, and
Liability Act
CHF – Contaminant Hazard Factor
DoD - Department of Defense
EPA – US Environmental Protection Agency
FTA – Fire Training Area
HA – Health Advisory
MPF – Migration Pathway Factor
PA – Preliminary Assessment
PFAS - Per-and polyfluoroalkyl substances
PFBS – Perfluorobutanesulfonic acid
PFOS - Perfluorooctane sulfonate
PFOA - Perfluorooctanoic acid
RCRA – Resource Conservation and Recovery Act
RF – Receptor Factor
RI – Remedial Investigation
RRSE – Relative Risk Site Evaluation
PRL - Potential Release Location
FI – Facility Investigation
SWMU – Solid Waste Management Unit

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