PFAS in Landfills

PFAS enter landfills in a variety of ways:

  • Municipal Solid Waste — In 2017 the US EPA estimated about 138 million tons of MSW is landfilled each year. We have established 10,000 PPT as representative of overall MSW PFAS content. Based on these figures, we estimate that about 2,755 lb. (1,250 kg) of PFAS chemicals go into US Landfills every year.
  • Biosolids — Landfilling biosolids contributes between 1,030–1,295 lbs (470–590 kg) of PFAS per year.
  • Cover Soils — PFAS input with cover soils is calculated to be 123.9 lbs (56.2 kg) per year.
  • Precursors — A lack of analytical standards limits the quantification of perfluoroalkyl acids (PFAA) in precursor compounds.
  • Precipitation — PFAS input from rainwater is calculated to be 1.35 lbs (0.61 kg/year) per year.

In total, we estimate the total PFAS inputs to landfills to be between 4,477–4,823 lbs (2,030.7–2,187.7 kg) per year.

While landfills might serve as long-term containment sites for PFAS, they have not been designed explicitly for PFAS containment. The largest landfill challenge is in keeping PFAS compounds out of landfill leachate.

How landfills sequester PFAS

Construction of a landfill and installation of geomembrane

Subtitle D Clay Liners

Single-layer clay liners (such as uncoated bentinite) may not be effective at sorbing PFAS chemicals.

Geosynthetic Landfill Covers

Geosynthetic Landfill Covers have been successful in keeping PFAS compounds from seeping into groundwater. Testing on LLDPE co-extruded with EVOH have found negligible source depletion, indicating limited contaminant partitioning and diffusion.