Life cycle evaluation of PFAS remediation scenarios

Perfluorinated chemicals are legacy contaminants that are ubiquitous in our environment and in our bodies. Adverse health effects have been linked to exposure to these chemicals and health advisories have been published by the... [ view full abstract ]

Perfluorinated chemicals are legacy contaminants that are ubiquitous in our environment and in our bodies. Adverse health effects have been linked to exposure to these chemicals and health advisories have been published by the EPA at 70 parts-per-trillion. Removal of perfluorinated compounds from drinking water sources is challenging and treatment times are long. When deciding the proper course of action to handle these legacy contaminants, expediency and financial cost are usually the driving factors. The primary goal is to reduce downstream exposure and associated risks to human health from known contaminants. This research considers the life cycle impacts of remediation systems on human health, resource use, and ecotoxicity.

We compare a range of case studies for supplying drinking water to residents and workers near a groundwater source contaminated with perfluorinated compounds. Case studies include conventional pump-and-treat remediation strategies, point-of-use treatment, and delivery of non-contaminated drinking water in single-use or reusable plastic containers. Data sources include operational data from treatment systems at several US Department of Defense installations and private-sector sites, novel experimental data, and current scientific literature. Case studies are modeled using SimaPro life cycle assessment software on the common basis of 1 m³ drinking water.

Results indicate that there are clear advantages to centralized pump-and-treat facilities over delivered bottled water. Production and disposal of plastic bottles has human health, resource use, and ecotoxicity impacts orders of magnitudes higher than other drinking water supply methods, though these differences can be dramatically reduced by providing reusable containers and coordinating distribution of drinking water. Granular activated carbon may have lower health and resource impacts than ion-exchange resin, the alternative leading technology for remediation of perfluorinated compound contaminated groundwater. However, differences between these methods depend heavily on assumptions regarding material use efficiency and waste disposal methods. Stochastic analyses show that the range of likely impacts for each remediation method can exceed an order of magnitude. This uncertainty emphasizes the importance of detailed case studies and improved data quality in life cycle assessments.

Our analyses support decision-makers tasked with finding effective, efficient, and sustainable methods for perfluorinated compound remediation. The selected case studies showcase the costs and benefits of remediation systems and identify target areas for improvement in system design, logistics, and energy use.