Emerging contaminants are a challenge for contaminated sites as they add uncertainty and cost to strategies for characterization and remediation. Advancing these strategies requires a substantial investment in research and development, as the chemical properties of emerging contaminants are often not well understood. In the early 2000s, multiple emerging contaminants were identified, including MTBE and oxygenates, 1,4-dioxane, NDMA, perchlorate, select pharmaceuticals, PFOS and others. Roll forward to 2019 and we can see that systematic and effective approaches to address some of these contaminants (i.e., MTBE) have been developed, while some contaminants continue to pose challenges (perchlorate, 1,4-dioxane) all while other emerging contaminants continue to be identified. Emerging contaminants such as TBA, 1,4-dioxane, perchlorate, pharmaceuticals, perfluorylalkyl substances (PFAS), selenium, microplastics and sulfolane are an on-going concern at many sites. With the development of new chemicals for various commercial, pharmaceutical, industrial and military purposes, we can expect that we will continue to face new emerging contaminants in the future.
This presentation will discuss the history of emerging contaminants of concern at contaminated sites. It will then provide a focused discussion on several current emerging contaminants, including PFAS, 1,4-dioxane, selenium and sulfolane. This will include the use history and key characteristics that challenge remediation practitioners in developing investigation and remedial strategies. Finally, recent advances in remediation tools for these compounds will be discussed including both ex situ and in situ options. Case study results for promising technologies that can provide treatment of each of these constituents will be provided.