The Pennsylvania Department of Environmental Protection (“PADEP”) published guidance regarding registering and permitting storage tanks that contain perfluorooctanoic acid (“PFOA”), perfluorooctanesulfonic acid (“PFOS”). This change comes in light of a recent EPA rule under Federal Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”), which added PFOA and PFOS substances to the hazardous substances list.  The EPA rule is effective July 8, 2024.  As a result, under the Pennsylvania Storage Tanks and Spill Prevention Act (“Tanks Act”) and related regulations under 25 Pa. Code Chapter 245, any storage tank containing more than a de minimis concentration of PFOA, PFOS, or their salts and structural isomers are now regulated.

A key component of the PADEP storage tank program is that aboveground or underground tanks that store a “regulated substance” must be registered and permitted by PADEP.  As defined under the Tanks Act and 25 Pa. Code Chapter 245, a “regulated substance” includes any substance defined as a “hazardous substance” under the CERCLA. Because PFOA and PFOS are now recognized as hazardous substances under CERCLA, they are automatically incorporated into the definition of a “regulated substance” under the Tanks Act and 25 Pa. Code Chapter 245.

In general, any aboveground tank with a capacity of more than 250 gallons or any underground tank with a capacity of more than 110 gallons that contains a regulated substance above a de minimis concentration must be registered with the DEP Storage Tanks Program unless it meets an exemption. The term “de minimis” is defined to mean a concentration that is insufficient to be required to appear on a Safety Data Sheet.  Generally, per the Occupational Safety and Health Administration (“OSHA”) requirements, a Safety Data Sheet must list a chemical substance that presents a health hazard if it makes up more than 1% of a mixture, or 0.01 % if the substance is carcinogenic.  Note, OSHA has not formally listed PFOA or PFOS as toxic or hazardous substances under OSHA regulations.  See 29 CFR 1910, Subchapter Z.

PADEP notes in its guidance that PFOS and PFOA have historically been used in producing, stain resistant carpets and fabric, cosmetics, and firefighting foams, among other items.  Instructions on how to register a storage tank containing PFOA, PFOS, or their salts and structural isomers are available here.