Challenges and Treatment Solutions for Small Drinking Water Systems

EPA's Office of Research and Development and Office of Water host this monthly webinar series to communicate current small drinking water systems research along with Agency priorities. This forum allows EPA to communicate directly with state personnel and others to provide training and foster collaboration and dissemination of information. This, in turn, provides state agencies with the information and resources needed to communicate the latest scientific advancements and current guidance to their small systems. The webinars also provide EPA with invaluable information from the states on challenges they are currently encountering in their interactions with small systems. With this information, EPA scientists and engineers can modify their research to find solutions to real-world problems. Presentation 1—Treatment for Contaminants of Emerging Concern (CECs): Per- and Polyfluoroalkyl Substances (PFAS), Cyanotoxins, and Perchlorate (Presented by Thomas Speth, EPA's Office of Research and Development). This presentation will discuss treatment for three CECs—PFAS, cyanotoxins, and perchlorate—with an emphasis on determining cost-effective solutions for small systems. Specifically, how contaminant properties influence treatment effectiveness, operational complexity, cost, and residual stream handling will be discussed. Also, novel technologies will be discussed using anaerobic biofiltration of nitrate as an example, and a demonstration on the impact of system size to capital and operating costs will be shown. For each technology and contaminant, how to avoid unintended consequences, such as increase water corrosivity or residual handling problems, will be covered. Presentation 2—Treatment Approaches for 1,4-Dioxane in Reuse and Groundwater (Presented by Brian Bernados, California EPA's State Water Resources Control Board). By statute, California has established Notification Levels for some chemicals seen in both wastewater and groundwater that do not currently have Maximum Contaminant Levels, including 1,4-dioxane. To achieve 1,4-dioxane reduction below the Notification Level of 1 ppb, California regulations require full advanced treatment for groundwater injection and surface water augmentation projects, which includes reverse osmosis treatment and advanced oxidation processes. This presentation will cover the role that 1,4-dioxane plays in both drinking water and potable reuse in California. A drinking water example of a groundwater treatment process will also be covered.