Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Contamination of groundwater with per- and polyfluoroalkyl substances (PFAS) from legacy landfills in an urban re-development precinct
The extent of per- and polyfluoroalkyl substances (PFAS) in groundwater surrounding legacy landfills is currently poorly constrained. Seventeen PFAS were analysed in groundwater surrounding legacy landfills in a major Australian urban re-development precinct. Sampling locations (n?=?13) included sites installed directly in waste material and down-gradient from landfills, some of which exhibited evidence of leachate contamination including elevated concentrations of ammonia-N (?106?mg/L), bicarbonate (?1,740?mg/L) and dissolved methane (?10.4?mg/L). Between one and fourteen PFAS were detected at all sites and PFOS, PFHxS, PFOA and PFBS were detected in all samples. The sum of detected PFAS (?14PFAS) varied from 26?ng/L at an ambient background site to 5,200?ng/L near a potential industrial point-source. PFHxS had the highest median concentration (34?ng/L; range: 2.6–280?ng/L) followed by PFOS (26?ng/L; range: 1.3–4,800?ng/L), PFHxA (19?ng/L; range: <LOQ – 46?ng/L) and PFOA (12?ng/L; range: 1.7–74?ng/L). Positive correlations between ?14PFAS, PFOA and other perfluoroalkyl carboxylic acids (PFCAs) (e.g. PFHxA) with typical leachate indicators including ammonia-N and bicarbonate were observed. In contrast, no such correlations were found with perfluoroalkyl sulfonic acids (PFSAs) (e.g., PFOS and PFHxS). In addition, a strong positive linear correlation (R2?=?0.69) was found between the proportion of PFOA in the sum of detected perfluorinated alkylated acids (PFOA/?PFAA) and ammonia-N concentrations in groundwater. This is consistent with previous research showing relatively high PFOA/?PFAA in municipal landfill leachates, and more conservative behaviour (e.g. less sorption and reactivity) of PFCAs during subsurface transport compared to PFSAs. PFOA/?PFAA in groundwater may therefore be a useful indicator of municipal landfill-derived PFAA. One site with significantly elevated PFOS and PFHxS concentrations (4,800 and 280?ng/L, respectively) appears to be affected by point-source industrial contamination, as landfill leachate indicators were absent.
» Author: Emily Hepburn, Casey Madden, Drew Szabo, Timothy L. Coggan, Bradley Clarke, Matthew Currell
» Publication Date: 01/05/2019
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
