Remediation of groundwater and soil impacted by per- and poly-fluoroalkyl substances using novel modified clays

水成膜泡沫（AFFF）的使用和释放导致在许多联邦和私人设施中检测到全氟烷基和多氟烷基表面活性剂（PFAS）水平升高，例如消防培训场所、消防设备测试场所、炼油厂等。这是一个全球性问题，发达国家登记了一些污染最严重的场所，影响土壤和水质。有些PFAS具有持久性、生物累积性和毒性。在PFAS严格法规的推动下，迫切需要具有成本效益和高效的污染土壤和地下水处理技术。我们建议该项目，与CETCO（美国）和Sanexen环境服务（加拿大）合作，开发基于粘土的修复技术。我们计划评估为PFAS明确开发的改性粘土的性能。通过实验室实验，我们计划确定影响性能的关键环境因素和吸附剂特性，阐明改性粘土与各种结构和功能的PFAS之间的相互作用机制，并在必要时提出改进现有商业产品的解决方案。我们预计，到项目结束时，我们将准备好为特定的污染场地提出和设计处理战略，并进行实地试验。我们希望在该项目中开发的新知识将提高对新粘土产品利弊的理解，并可能为未来的产品开发做出贡献。三方合作旨在开发新的处理技术，以处理北美市场急需的新型土壤和水污染物。与污染土壤的场外处置相比，改性粘土的原位处理有可能大大降低补救成本，这将有利于加拿大和美国，因为它降低了处理大量污染场地中PFAS污染的成本。

The use of and release of aqueous film-forming foams (AFFFs) has led to the detection of elevated levels of per- and polyfluoroalkyl surfactants (PFASs) in many federal and private facilities, such as fire-fighting training sites, fire equipment testing sites, oil refineries, etc. It is a global problem with developed countries registering some of the most polluted sites, impacting soil and water quality. Somes PFAS are persistent, bioaccumulative, and toxic. Driven by the stringent regulations on PFAS, there are urgent needs for cost-effective and efficient treatment technologies for contaminated soil and groundwater. We propose the project, in partnership with CETCO (USA) and Sanexen Environmental Services (Canada), to develop clay-based remediation technologies. We plan to evaluate the performance of the modified clay that was explicitly developed for PFAS. Using laboratory experiments, we plan to identify key environmental factors and sorbent characteristics that affect performance, elucidate the mechanisms of interactions between modified clays and PFASs of various structures and functionalities, and if necessary, suggest solutions to improve the existing commercial products. We expect that by the end of the project, we will be ready to propose and design treatment strategies for a given contaminated site and conduct field trials. We expect that new knowledge developed in the project will improve the understanding of the pros and cons of the new clay products, and potentially, to contribute to future product development. The collaboration among the three parties is geared towards developing new treatment technologies for treating a new category of soil and water pollutants, which is greatly needed for the North America market. As compared with the off-site disposal of contaminated soil, in situ treatment enabled by modified clay has the potential to significantly reduce remediation costs, which will benefit Canada and the USA by reducing the cost of dealing with PFAS contamination in a high number of contaminated sites.