Environmental Alert
(by Matt Wood and Mackenzie Moyer)
On February 26, 2022, the Environmental Quality Board (EQB) published a proposed rule to amend 25 Pa. Code Ch. 109 (Safe Drinking Water) to regulate certain per- and polyfluoroalkyl substances (PFAS). 52 Pa. B. 1245. Specifically, the rule proposes setting a maximum contaminant level goal (MCLG) and maximum contaminant level (MCL) for both perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). PFOA and PFOS are two of the most common PFAS, a “family” of thousands of synthetic chemicals that have been used in consumer, commercial, and industrial applications since the 1940s. PFAS have been used to manufacture water-, stain-, and heat-resistant products and have been a common component in some aqueous film forming foams (AFFF) routinely used for firefighting. PFAS have been found in various environmental media like groundwater (including drinking water), plants, animals, and in humans. Because PFAS do not break down naturally in the environment, they have been called “forever chemicals.” Evidence suggests that PFAS exposure can lead to adverse health effects.
The proposed rule sets MCLGs of 8 parts per trillion (ppt) for PFOA and 14 ppt for PFOS and MCLs of 14 ppt for PFOA and 18 ppt for PFOS. The MCLGs are nonenforceable levels developed solely from health effects data and act as the starting point for determining the MCLs. To develop the enforceable MCLs, the Pennsylvania Department of Environmental Protection (PADEP) considered factors beyond health effects data, including technical limitations and costs that may affect the feasibility of achieving the MCLGs. As part of the rulemaking process, PADEP also considered PFAS other than PFOA and PFOS (i.e., PFNA, PFHxS, PFHpA, PFBS, and HFPO-DA), but proposed not establishing MCLs for these substances at this time, primarily due to a lack of occurrence data and incomplete cost/benefit data and analysis. …