Grantee Research Project Results
2022 Progress Report: Characterization and Quantification of per- and polyfluoroalkyl substances in landfill gas and estimate of emissions from U.S. Landfills
EPA Grant Number: R839600Title: Characterization and Quantification of per- and polyfluoroalkyl substances in landfill gas and estimate of emissions from U.S. Landfills
Investigators: Barlaz, Morton A. , Field, Jennifer , Simonich, Staci
Institution: Oregon State University , North Carolina State University at Raleigh
EPA Project Officer: Hahn, Intaek
Project Period: September 1, 2019 through August 31, 2022 (Extended to August 31, 2024)
Project Period Covered by this Report: September 1, 2021 through August 31,2022
Project Amount: $900,000
RFA: Practical Methods to Analyze and Treat Emerging Contaminants (PFAS) in Solid Waste, Landfills, Wastewater/Leachates, Soils, and Groundwater to Protect Human Health and the Environment (2018) RFA Text | Recipients Lists
Research Category: Drinking Water , Human Health , Water , Water Quality , PFAS Treatment
Objective:
The overall research objective is to estimate the mass of per- and polyfluoroalkyl substances (PFAS) that are present in landfill gas (LFG) and the mass of PFAS emitted as fugitive emissions. Sub-objectives are to: (1) develop methods to sample and analyze LFG for targeted and non-targeted PFAS; (2) measure PFAS concentrations at a cross section of U.S. landfills in different climatic regions; (3) develop a model to estimate PFAS production and emissions at the U.S. national scale; (4) evaluate the potential impact of soil attenuation on PFAS emissions; (5) measure gas-phase PFAS release from mixed waste and food packaging materials.
Progress Summary:
Task 1: Develop methods to sample and analyze PFAS in LFG
We have developed a sampling system to collect landfill gas (LFG) and analyze samples for PFAS by thermal desorption gas chromatography coupled with mass spectrometry (TD-GC-MS). A total of 47 target, semi-quantitative, and suspect volatile PFAS from nine classes are being analyzed including fluorotelomer alcohols (4:2, 6:2, 8:2, and 10:2 FTOHs), C8 perfluorinated sulfonamides (N-MeFOSA, N-EtFOSA), and C8 perfluorinated sulfonamidoethanols (N-MeFOSE, N-EtFOSE). Suspect PFAS include the C2 -C7 perfluorinated sulfonamidoethanols and14:2-FTOH. A manuscript has been submitted and is in revision.
Task 2: Measure PFAS concentrations at a cross section of US landfills in different climate regions.
We have identified a total of 28 landfills in arid, moderate and wet regions of the U.S. and have sampled 23 landfills once and 28 landfills twice. The preliminary data for eight wet landfills is presented in Figure 2 and shows that PFAS in LFG is dominated by fluorotelomer alcohols. We have also detected minor components such as olefins and acrylates.
Figure 1. Fluorotelomer alcohols dominate the PFAS in landfill gas from 8 wet landfills (precipitation > 40 in./yr.). MHD – Main Header Upstream; MHU – Main Header Downstream; WHN – Well Head New (<5 y); WHN – Well Head Old (>10 y). The horizontal line in the middle is the median and the outer edges are the inter – quartile (middle 50%). The lines that extend from the outer edges are upper and lower quartiles.
Task 3: Develop a model to estimate PFAS production and emissions at the US national scale. To quantify the mass of PFAS released in LFG, a national inventory of LFG generation, collection, and fugitive emissions was developed using data and methodology from the U.S. EPA Greenhouse Gas Inventory and the U.S. EPA’s Landfill Methane Outreach Program database. Using available data, we have estimated the volume of LFG that is generated, recovered (flared or energy recovery) and emitted in each climatic region of the U.S. We will apply the PFAS concentration data developed in Task 2 to estimate a U.S. inventory for PFAS in LFG using equation 1.
PFAS Emissins
= Σ {ConcPFAS,i
iε{arid,moderate,wet}
x[Vfugitive LFG,i X(1 -- PFAS soil attenuation factori)
+ VLFG flared,i X(1 -- DEflare) + VLFG for energy, i x (1 -- DEenergy)]}
Task 4: Assess the impact of soil on the attenuation of PFAS in LFG that is not collected.
The objective of this task is to evaluate the potential for the attenuation or transformation of PFAS in landfill cover soils. We have fabricated a static chamber for this task to measure the concentration signature of PFAS that has been released through a soil cover. We have completed four flux measurements as planned. The changes in PFAS chemical signatures within the cover soil and the static chamber will provide evidence of PFAS attenuation, if any occurs.
Task 5: Measure the production of volatile PFASs from residential MSW and food waste packaging during anaerobic decomposition.
We have identified 11 packaging samples that contain PFAS and have tested these compounds in a reactor system in which we simulated anaerobic decomposition in a landfill. Gas from the reactors was sampled multiple times during the decomposition cycle. The results from initial gas samples show that the packaging materials with higher F release considerably more PFAS (primarily 6:2 FTOH) relative to the low F samples.
Journal Articles:
No journal articles submitted with this report: View all 14 publications for this projectSupplemental Keywords:
landfill gas, emissions inventory, landfill model, food packaging, PFASRelevant Websites:
NC STATE De la Cruz Research Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.