The Environmental Protection Agency has proposed to list two “forever chemicals”—perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)—as “hazardous substances” under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or Superfund). See 87 Fed. Reg. 54,415 (Sept. 6, 2022). For some this is a hair-on-fire moment, so let’s pause and evaluate what difference that listing would actually make if it became final.

To start, be clear that listing as a “hazardous substance” does not make a material containing PFOA or PFOS necessarily a “hazardous waste” subject to special regulation under the federal Resource Conservation and Recovery Act (RCRA) or the Pennsylvania Solid Waste Management Act. That is particularly true at the extraordinarily low concentrations for PFOA or PFOS on which some are focused. Industrial wastes or contaminated soils in Pennsylvania are typically regulated as “residual waste.” Household waste, even waste containing detectable PFOA or PFOS, is still just municipal solid waste.