Drinking Water Contaminants
In addition to the Center's original mission focusing on the removal of nitrogen from wastewater, the Center has begun researching the development and evaluation of methods to remove emerging contaminants from drinking water supplies. This effort represents the initial phase of a State-sponsored, multi-year program to proactively address emerging contaminants in drinking water.
For inquiries related to the Center's Drinking Water Research please contact Dr. Arjun Venkatesan, Associate Director for Drinking Water Initiatives.
1,4-Dioxane is a probable human carcinogen and a widespread contaminant in Long Island's water supplies, with some of the nation’s highest concentrations detected (up to 33 μg L -1). The Center has established a pilot program to test the effectiveness and feasibility of advanced/alternative water treatment technologies (e.g. Advanced Oxidation Processes (AOP) such as UV/H2O2 treatment) to remove 1,4-dioxane from drinking waters. The program has three interrelated objectives:
- providing grants to support the pilot testing of treatment technologies by water suppliers;
- evaluating the efficacy of pilot treatment technologies; and
- research and development of novel or refined treatment technologies to remove 1,4-dioxane and associated byproducts from drinking water.
Research is being conducted to (i) understand the fate and transformation of 1,4-dioxane and formation of other toxic reaction byproducts during AOP treatment, and (ii) test a combination of treatment techniques with AOP (e.g. Granular Activated Carbon (GAC), Biological Activated Carbon (BAC) etc.) to enhance the removal of 1,4-dioxane and associated byproducts.
Advanced Oxidation Processes
Advanced Oxidation Processes (AOPs) refer to highly efficient chemical treatment methods designed to remove many persistent organic contaminants (e.g., pesticides, 1,4-dioxane) that are resistant to conventional water treatment techniques. AOPs rely on the production of highly reactive chemical species, such as hydroxyl radicals, to breakdown contaminants and convert them into water, carbon dioxide, salts, and mineral acids. AOPs can be employed in many different configurations as long as reactive radical species can be generated. For example, a combination of ultra-violet (UV) and hydrogen peroxide (UV/H2O2), UV and titanium dioxide (UV/TiO2), UV and chlorine, UV and ozone (UV/O3), peroxone (O3/H2O2) have been reported to effectively treat contaminated waters. AOP systems are increasingly being installed in water facilities across NYS to treat 1,4-dioxane-contaminated groundwater.
In order to commercialize and use such systems for the treatment of public drinking water, in-depth understanding of the system performance, optimum conditions, source water quality impacts, potential degradation pathways of 1,4-dioxane, and by-product formation in treated waters/distribution systems are needed. Our Center is leading a pilot program across Long Island, NY to evaluate and compare various pilot-scale AOP systems to inform water providers and regulatory agencies on their performance and feasibility to treat 1,4-dioxane-contaminated groundwater.
In addition to the pilot program, laboratory-scale research is being conducted to (i) understand the fate and transformation of 1,4-dioxane, and formation of other toxic reaction byproducts during AOP treatment, and (ii) test combination of other treatment techniques with AOP (e.g. Granular Activated Carbon (GAC), Biological Activated Carbon (BAC) etc.) to enhance the removal of 1,4-dioxane and their byproducts.
Reference: Lee, C. -S., Venkatesan, A. K., Walker, H. W., & Gobler, C. J. (2020). Impact of groundwater quality and associated byproduct formation during UV/hydrogen peroxide treatment of 1,4-dioxane.Water Research, 173, 115534.
The Center is also conducting research to address the increasing concern of poly- and perfluoroalkyl substances (PFAS) contamination in NYS drinking water sources. PFAS are manmade chemicals that have been widely used in various commercial and industrial products since the 1950s. As a result, PFAS are released into the environment at significant quantities and have been detected in surface water, groundwater, animals, and humans worldwide. In order to assess Long Island water quality, the Center is in the process of establishing a testing facility to monitor a wide suite of PFAS using state-of-the-art instrumentation and methods. In addition, the Center will work closely with state, county, and local agencies to:
- evaluate the efficiency of existing treatment approaches (GAC, ion-exchange treatment, and advanced oxidation processes) in removing PFAS;
- research and develop novel or refined treatment technologies (novel sorbents and/or combination of technologies) to enhance the removal of PFASs from drinking water; and,
- scale-up, build and test the feasibility of using select novel/refined treatment technologies for pilot-scale treatment (point-of-use and point-of-entry) of contaminated drinking water.
Electron Beam Treatment
Our Center associate director (Dr. Venkatesan) was awarded a U.S. Department of Energy grant to evaluate high energy electron beam accelerator to treat emerging contaminants in drinking water. to Electron beam (e-beam) is a destructive technique that has been used in the past to degrade contaminants. Similar to a particle accelerator, the technology works by generating electrons by heating a filament. The electrons then travel along a high voltage electric field in a high vacuum accelerator tube to ensure a linear trajectory of the electrons. These electrons are scanned in the x-y direction and pass through a titanium foil/window before interacting with the matrix (in our case, contaminated water).
The interaction with water leads to the production of highly reactive species, such as hydroxyl radicals and solvated electrons, that can potentially degrade persistent chemicals. However, widespread application of this technology is limited due to its energy intensiveness. We are currently partnering with the Illinois Accelerator Research Center to test the degradation of persistent contaminants by a novel e-beam treatment tool. This technology is designed to be portable and energy-efficient than previous accelerators. We are investigating the efficacy of the e-beam technology to decompose both PFAS and 1,4-dioxane at environmentally relevant concentrations in water. In addition to the degradation of these persistent compounds, we are also evaluating the byproducts derived from them during the e-beam treatment.