Robey Nicole M, Liu Yalan, Tolaymat Thabet M, Bowden John A, Solo-Gabriele Helena, Townsend Timothy G
Innovative Technical Solutions, LLC, Gainesville, FL 32606, United States; University of Florida, Department of Environmental Engineering Sciences, College of Engineering, Gainesville, FL 32611, United States.
Florida Atlantic University, Department of Civil, Environmental and Geomatics Engineering, Boca Raton, FL 33431, United States.
J Hazard Mater. 2025 May 24;494:138705. doi: 10.1016/j.jhazmat.2025.138705.
Per- and polyfluoroalkyl substances (PFAS) are a growing concern due to their persistence, bioaccumulation potential, and continued widespread use in consumer products. PFAS disposed of in landfills are emitted to the environment via leachate, which drives a need to better understand PFAS behavior in landfills and landfill liner systems. This study examines PFAS concentrations in primary and secondary leachate from three municipal solid waste landfills utilizing double HDPE geomembrane liner systems. Samples were also analyzed for physical-chemical constituents such as chloride, ammonia, chemical oxygen demand, and metals. On average, physical-chemical parameter concentrations were significantly lower in the secondary compared to the primary leachate, although PFAS concentrations were not significantly different between leachate sources. Concentrations of chloride in groundwater and primary leachate were used to calculate expected PFAS concentrations in the secondary leachate. PFAS concentrations in secondary leachate were often higher than expected, with PFAAs more likely to exceed expected levels. Of the 92 PFAS analyzed, 50 were quantified in primary leachates and 48 in secondary leachates. The ∑PFAS concentrations in primary leachate ranged from 3200-81,000 ngL, and secondary leachate ranged from 3300-96,000 ngL. Possible explanations for the disproportionately high PFAS concentrations in secondary leachates, including residence time, transformation, liner sorption, and other PFAS sources (e.g., landfill gas) are explored. While liner systems are highly effective, PFAS migration through landfill liners and potential groundwater impacts remain a concern. This study underscores the importance of continued research into PFAS migration mechanisms and the potential environmental impacts of unidentified precursor PFAS in landfills.
全氟和多氟烷基物质（PFAS）因其持久性、生物累积潜力以及在消费品中的持续广泛使用而日益受到关注。在垃圾填埋场处置的PFAS通过渗滤液排放到环境中，这促使人们需要更好地了解PFAS在垃圾填埋场和垃圾填埋场衬垫系统中的行为。本研究考察了三个使用双层高密度聚乙烯土工膜衬垫系统的城市固体废弃物填埋场的一次和二次渗滤液中的PFAS浓度。还对样品的物理化学成分进行了分析，如氯化物、氨、化学需氧量和金属。平均而言，二次渗滤液中的物理化学参数浓度明显低于一次渗滤液，尽管不同渗滤液来源的PFAS浓度没有显著差异。利用地下水和一次渗滤液中的氯化物浓度来计算二次渗滤液中预期的PFAS浓度。二次渗滤液中的PFAS浓度往往高于预期，全氟烷基酸更有可能超过预期水平。在分析的92种PFAS中，一次渗滤液中有50种被定量，二次渗滤液中有48种被定量。一次渗滤液中∑PFAS浓度范围为3200 - 81000 ng/L，二次渗滤液中范围为3300 - 96000 ng/L。探讨了二次渗滤液中PFAS浓度过高的可能原因，包括停留时间、转化、衬垫吸附以及其他PFAS来源（如填埋气）。虽然衬垫系统非常有效，但PFAS通过垃圾填埋场衬垫的迁移以及对地下水的潜在影响仍然令人担忧。本研究强调了持续研究PFAS迁移机制以及垃圾填埋场中未识别的前体PFAS的潜在环境影响的重要性。
