Grantee Research Project Results
2023 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, 2022 through August 31,2023
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 , Water Quality , Human Health , Water , 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. Subobjectives are to: (1) develop methods to sample and analyze LFG for 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 (from
4:2 to 12:2 FTOHs), C8 perfluorinated sulfonamides (N-MeFOSA, N-EtFOSA), and C8 perfluorinated sulfonamidoethanols (N-MeFOSE, N-EtFOSE).
Task 2: Measure PFAS concentrations at a cross section of US landfills in different climate regions.
We have sampled from 28 landfills in arid, moderate and wet regions of the U.S. Based on an initial analysis of the data, the 6:2, 8:2, 10:2 and 12:2 FTOH comprise 50.9, 29.0, 11.5 and 5.8% of the total PFAS, respectively. The total PFAS concentration, across all samples analyzed is 5 x107 pg/m3. These numbers will shift slightly as the data are filtered but are helpful to obtain an initial estimate of PFAS in LFG.
FTOH
Figure 1. Fluorotelomer alcohols dominate the PFAS in landfill gas from based on the analysis of 447 samples collected from 28 landfills located in 17 different states in the US. Landfill classification is based on precipitation adapted from EPA Greenhouse Gas reporting rule as given in Table 1. The horizontal line in the middle is the median and the outer edges are the inter – quartile range (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. We estimate that 21,862 million m3 (mM3) of LFG are treated by a flare or engine and 22,978 Mm3 LFG are released as fugitive emissions. While preliminary, at an average total PFAS concentration of 5 x 107 pg/m3, this would result in 1150 kg/yr of PFAS in fugitive LFG, assuming 100% PFAS destruction efficiency in a flare or engine and 0% PFAS attenuation in soil. The volumes of LFG that are released by fugitive emissions and treated in a flare or engine are within 5%. Thus, estimated emissions will increase if PFAS destruction in a flare or engine is incomplete. To put this estimate into some context, we estimated that 660 kg/yr of PFAS are released to wastewater treatment plants in 2017.
Task 4: Assess the impact of soil on the attenuation of PFAS in LFG that is not collected.
At one site, results show comparable PFAS signature in the waste mass compared with the PFAS signature in the chamber sample (emission from landfill surface) suggesting marginal PFAS transformations for the target PFAS as it passes through the soil.
Figure 2. Relative concentration of PFAS in probe and chamber samples in one of the test sites showing comparable PFAS signature.
Task 5: Measure the production of volatile PFASs from residential MSW and food waste packaging during anaerobic decomposition.
We have demonstrated higher PFAS release to the gas phase during anaerobic decomposition from samples of food packaging that were shown to contain elevated PFAS. Elevated PFAS was defined as F > 3.8×105 ppm based on PIGE and > 1490 ng/g based on methanol extractable 6:2 FTOH.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
| Other project views: | All 15 publications | 3 publications in selected types | All 3 journal articles |
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Titaley IA, De la Cruz FB, Barlaz MA, Field JA. Neutral per-and polyfluoroalkyl substances in in situ landfill gas by thermal desorption–gas chromatography–mass spectrometry. Environmental Science & Technology Letters 2023;10(3):214-221. |
R839600 (2023) R839600 (Final) |
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Supplemental Keywords:
landfill gas, emissions inventory, landfill model, food packagingProgress 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.