Emerging Contaminants Short Course 2023

Dr. Patrick McNamara is an associate professor of Environmental Engineering at Marquette University and a Wastewater Process Engineer with Black & Veatch. He has over 15 years experience in wastewater solids and residuals management, and his research group has investigated emerging contaminants for a decade. His work is funded by the National Science Foundation, utilities, companies, and foundations. He has over 60 peer-reviewed journal publications.

Abstract

Pyrolysis for the removal of PFAS from biosolids.

PFAS in biosolids has resulted in Maine banning land application of biosolids. Other states are considering restrictions on land application as well due to PFAS. As a result, interest in thermal treatment processes have recently grown. Pyrolysis is a thermal treatment process that converts biosolids into biochar, pyrolysis-liquid, and pyrolysis-gas. This presentation will cover the benefits and drawbacks of these products as well as an in-depth analysis of experimental work that investigated removal and transformation of PFAS during pyrolysis of biosolids.

Dr. Brooke Mayer is an Associate Professor in the Department of Civil, Construction and Environmental Engineering at Marquette University.  She graduated from the Environmental Engineering program at Arizona State University (B.S. – 2004, M.S. – 2006, Ph.D. – 2008), where she taught from 2008 – 2012.  Her research and teaching interests focus on physical/chemical water treatment, particularly microbial disinfection and nutrient recovery.

Alma Beciragic completed her PhD in Environmental Sciences and Engineering at the UNC Gillings School of Global Public Health in the Fall of 2020. As an EPA Science to Achieve Results (STAR), AWWA, and AMTA/USBR graduate fellow, Alma’s research applied various analytical and instrumental techniques for the detection and analysis of known and novel micropollutants. Alma joined Arcadis in September 2020, where she now serves as management consultant in the resilience global business area, supporting a range of water quality and operational management projects for utilities.

Abstract

Research on microplastics (typically inclusive of nanoplastics) has gained attention in recent years. In the Fall of 2022, California passed Senate Bill (SB) 1422, which requires the State Water Board to formally define “microplastics in drinking water,” mandates the adoption of a standard analytical method, and requires four years of microplastics monitoring in select water systems across the state with inclusion of results in Consumer Confidence Reports. Similar proposed legislation has been introduced by New Jersey and New York city council.

This presentation will provide a foundational understanding of microplastics as a contaminant in drinking water, including: 

• The nuances of characterizing microplastics (quantification, morphology, size, polymer type) and establishing a formal definition
• To what degree water treatment plants are able to remove microplastics
• Some of the technical challenges (and remaining knowledge gaps) in terms of sampling, analysis, and data comparison, and
• Lessons learned regarding methods for effective consumer messaging about microplastics in drinking water.

The purpose of this presentation is two-fold: (1) to discuss key questions around microplastics, as currently being addressed under Water Research Foundation (WRF) project 5185: Fate of Microplastics in Drinking Water Treatment Plants, and (2) to raise awareness of the valuable resources generated by WRF 5155: Developing Strategic Consumer Messaging for Microplastics in Drinking Water Supplies. Together, these WRF projects will help build institutional knowledge essential for the industry to successfully navigate a potential new regulatory challenge and engage concerned stakeholders.

Vicente Gomez-Alvarez is a microbiologist with the United States Environmental Protection Agency, Office of Research and Development in the Water Infrastructure Division at Cincinnati, Ohio with 20 years of experience in planning and executing a diverse and intensive research project to study the microbiome in built and natural environments. His research focuses on microbial ecology, including the application of genomic technologies and the use of computational and bioinformatics workflow platforms for the characterization of microbiomes. He has led research projects on technological solutions for economic and environmental sustainability. Vicente has a Ph.D. in Microbiology from the University of Massachusetts-Amherst and a B.S. in Industrial Microbiology and a M.S. in Biology from the University of Puerto Rico.

Abstract

Potential environmental and health risk effects of class B biosolids returning to land: linking the resistome to the microbiome

Biosolids are defined as the treated sewage sludge residuals that are left over after wastewater treatment and must undergo treatment to be land-applied because these raw residuals may contain pathogenic microbes. An increasing amount of antibiotics are released into wastewater through various sources and ultimately find their way into wastewater treatment plants. This work includes examining the resistome of raw sludge, digestive sludge, and Class B biosolid samples collected from wastewater treatment plants in the United States and utilized culture techniques and cultivation-independent metagenomics to link the antimicrobial resistance to their microbial hosts. This information can be incorporated into ecosystem models and enhance our ability to estimate the risk of dissemination of resistance genes and mechanisms from these reservoirs. 

Veronika Folvarska is a second-year graduate student working towards a PhD at Marquette University. Pursuing her academic journey with enthusiasm, Veronika's research centers on the critical issue of antibiotic resistance and its relationship with corrosion products. By developing and merginging her understanding of chemistry, microbiology, and engineering, Veronika aspires to contribute valuable insights to our understanding of antibiotic resisitance within drinking water systems.

Abstract

Impact of Corrosion Products Commonly Found in Drinking Water Distribution Systems on Antibiotic Resistance 

Antibiotic resistance has emerged as a pressing global health concern, necessitating comprehensive research to understand its diverse contributing factors. Metals are known stressors for antibiotic resistance, and one source of metals within drinking water distribution systems are corrosion products. This presentation will provide general introductory information regarding antibiotic resistance. Research regarding the influence of copper, lead, and iron corrosion products on the proliferation of antibiotic resistant bacteria and antibiotic resistance genes will be presented. 

Jennifer Guelfo, Ph.D., is an Assistant Professor and a Ed and Linda Faculyt Fellow in Civil, Environmental, and Construction Engineering at Texas Tech University. She joined Texas Tech University in 2018 following a postdoctoral appointment in the Brown University School of Engineering.  Dr. Guelfo has a BA in Geology from the College of Charleston, a MS in Environmental Science & Engineering from the Colorado School of Mines (CSM), and a PhD in Hydrologic Science and Engineering, also at CSM. For the past 13 years, her research has focused primarily on occurrence, fate, transport, and remediation of per- and polyfluoroalkyl substances (PFAS).  In addition to academia, she also has a combination of consulting and industry experience, and she uses this background to engage in activities that can inform policy and bridge gaps between research and practice.  

Abstract

Occurrence, leaching, and mobility of PFAS in biosolids and biosolids-amended soils 

Per and polyfluoroalkyl substances (PFAS) are not destroyed during wastewater treatment so they occur in wastewater residuals including effluent and biosolids.  Millions of tons of biosolids are generated in the U.S. each year and ~55% are land applied, which provides vital nutrients in agricultural settings. However, with increasing concerns regarding PFAS exposure, there are key questions regarding potential for plant uptake, surface runoff, and subsurface leaching of PFAS in biosolids and biosolids-amended soils. The latter may lead to impacts to aquifers used for drinking water and/or irrigation, but few studies have investigated the potential for PFAS leaching from biosolids-amended soils.  As a result, this study focuses on the occurrence of PFAS in 5 biosolids and 2 compost samples as well as the potential for leaching from biosolid amended soils using column studies coupled with high-resolution mass spectrometry (HRMS) analytical approaches. The sum of 40 PFAS analyzed during targeted analysis was 9.6 - 373 g/kg (0.04-0.78 mol/kg), and the most frequent detections were perfluorobutanoate (PFBA) and perfluorooctane sulfonate (PFOS). Total oxidizable precursor (TOP) assay resulted in increases in perfluoroalkyl carboxylates in all samples suggesting occurrence of unknown PFAS. After TOP, total PFAS concentrations increased to 0.09-3.90 mol/kg. Saturated, upflow column experiments were implemented soils amended with biosolids at agronomic rates as well as soils amended with biosolids and the stabilizers polyDADMAC. Biosolids amended soil columns resulted in near-simultaneous elution of short chain PFAS such as PFBA followed by elution of longer-chain PFAS such as perfluorooctanoate (PFOA). Addition of polyDADMAC had no influence on transport of short-chain PFAS, but resulted in increased retention of long-chain PFAS such as PFOA.

Sam is an Environmental Engineering M.S graduate and PhD student at Marquette University. She graduated from the University of Pittsburgh in 2020 during the height of the pandemic, which led her into the study of viruses, particularly in water and wastewater treatment.  Currently, her research is focused on virus inactivation using emerging disinfection systems.

Abstract

Viruses as an emerging contaminant in recycled wastewater

Water scarcity is an urgent issue in desperate need of innovative solutions, and water recycling is one of the most promising, straightforward alternatives.  However, viruses are a particularly detrimental threat to ensuring the safety of recycled water.   This presentation will discuss UV as a potential disinfection system for water recycling and how surrogate viruses can be useful for evaluating emerging disinfection systems.

Paul Westerhoff is a Regents Professor & Fulton Chair of Environmental Engineering at Arizona State University.  He has over 400 peer reviewed publications related to water. He is the Deputy Director of a NSF ERC  for Nanotechnology Enabled Water Treatment and co-Deputy Director of the NSF Science and Technologies for Phosphorus Sustainability Center . He received several awards including  the 2020 A.P. Black award from AWWA, 2019 NWRI Clarke Prize,  2013 ARCADIS/AEESP Frontier in Research Award, 2006 Paul L. Busch Award., and was elected to the National Academy of Engineering in 2023..

Abstract

Wastewater effluents impact PFAS concentrations at Drinking water treatment plants:  Sucralose and Predicted De facto Wastewater Reuse Levels Correlate with PFAS Levels in Surface Waters

PFAS are organic pollutants with widespread distribution, persistence, bioaccumulation, and health risks, detectable in wastewater effluents. WWTP effluents impact over half of surface water intakes for DWTPs, leading to widespread occurrence of PFAS in surface waters used for drinking water. For a large watershed in Texas was studied, where 165 WWTP discharges and dozens of DWTP intakes provide drinking water to nearly 6 million people. SPFAS in WWTP effluents ranged from 50 to 200 ng/L, and surface water samples found highly correlated levels of SPFAS and sucralose. WWTP discharges were the primary source of PFAS to the Trinity River. Based upon this insight we predicted for the entire USA impacts of de facto wastewater reuse as a ubiquitous source of PFAS for thousands of DWTPs nationally.

David Tobias has worked at the EPA for the past 14 years characterizing exposure to consumers, the general population, and ecological organisms for chemical risk assessments. His projects have included designing and evaluating testing for degradation, bioaccumulation, and sorption of chemicals including PFAS as well as implementing computer models for the fate of chemicals released to the environment. David is currently a risk assessor for the biosolids program in the Office of Water.

Abstract

Chemical Risk Assessment for PFOA/PFOS in Biosolids. 

PFAS are widespread in wastewater influent and sewage sludge due to industrial, commercial, and domestic sources. Within wastewater treatment plants some PFAS will associate mainly with the solids and disposal or use of sewage sludge/biosolids could lead to environmental exposures to PFAS. This talk will describe the conceptual model the EPA uses to evaluate environmental concentrations and exposures that result from land application of biosolids and how that model fits with PFAS risk assessment.

Dr. Jade Mitchell is an Associate Professor and Associate Chair of the Department of Biosystems and Agricultural Engineering at Michigan State University. Her research interests include risk assessment, understanding how chemical and microbial stressors from diverse environmental exposures including water quality and food safety lead to adverse human health outcomes. She uses quantitative analysis and modeling to characterize risks to support risk management decision making, engineering design and environmental policy. She is keenly interested in evaluating risk trade-offs between quality and quantity in multi-stressor environments. Dr. Mitchell is currently focused on evaluating risks associated with opportunistic pathogens and disinfection byproducts in drinking water distribution systems through a U.S. Environmental Protection Agency (EPA) funded National Priorities grant. Dr. Mitchell received her B.S. in 1997 from the University of Pittsburgh in Civil and Environmental Engineering. After graduation she worked for engineering consultant firms in project management and storm water design. A strong desire to understand and direct the “best management practices” she used in her daily work prompted her to purse an M.S. in Civil Engineering, which she obtained in 2007 followed by her Ph.D. in Environmental Engineering in 2010 from Drexel University. Prior to joining Michigan State University, Dr. Mitchell completed post-doctoral research with the U.S. EPA National Exposure Research Laboratory and the USDA Food Safety Inspection Service.

Abstract:  Using Quantitative Microbial Risk Assessment to Address Emerging Contaminants in Water and Wastewater

Quantitative microbial risk assessment (QMRA) is a research domain that addresses exposures to microbial pathogens and infectious disease processes in order to characterize human health effects. It has become a globally well-established framework for predictive and retrospective evaluations of health threats associated with exposure to etiological agents especially for establishing water quality and food safety standards. QMRA requires an understanding of biological processes- within the environment and as the result of interactions with human hosts; and methodology that focuses on dynamic and complex systems. QMRA can be used to set health-based targets for water and wastewater treatment and reuse. In this talk, the basic methodology, applications and data needs for emerging contaminant will be addressed. The utility of QMRA approaches to prioritize and evaluate risk management strategies to protect drinking water sources will be explored                    

Dr. Caoline Russell is a Principal Technologist with Carollo Engineers, Inc. with over 20 years of experience addressing drinking water supply and treatment challenges for water systems across the U.S. She has also helped more than two dozen water systems address distribution system water quality challenges including pipe corrosion, taste and odor control, nitrification, and disinfection by-product (DBP) formation. Dr. Russell helped direct the planning phase of the El Paso Water direct potable reuse (DPR) project, and is working on technical aspects of the detailed design for the project. She received her B.S. in Civil Engineering from Duke University and her Master's and PhD in Environmental Engineering from the University of Texas at Austin.

Abstract

Impact of GAC Treatment on DBP Formation and Toxicity in Drinking Water

Promulgation of the Stage 2 Disinfection By-Product Rule (DBPR) has prompted more utilities to implement strategies to reduce formation of regulated DBPs, including implementing GAC adsorption to facilitate continued use of chlorine as a disinfectant, switching to chloramines, or using aeration to strip the more volatile DBPs. The USEPA is currently considering revisions to the DBPR, recognizing that unregulated DBPs can be more toxic than the currently regulated DBPs. Changes to the DBPR could prompt more utilities to implement GAC, which can reduce DBP formation overall, but shift the bromide to DOC ratio and result in increased formation of the more toxic brominated DBPs. A major research gap is whether strategies that reduce regulated DBP formation translate to an overall reduction in the toxicity of the drinking water.

As part of a Water Research Foundation project, pilot testing and full-scale sampling were conducted to compare GAC adsorption to alternate approaches to control DBPs formation of regulated and unregulated DBPs and the resulting toxicity using bioassays. Pilot-scale GAC columns were operated to facilitate a side-by-side comparison of the impact of GAC with and without pre-chlorination and with different influent bromide (up to 300 µg/L) and iodide (up to 80 µg/L) concentrations. GAC influent and effluent samples were collected at ~20, 50, and 80% TOC breakthrough and chlor(aminated) under uniform formation conditions (UFC).

Full-scale samples were collected at two conventional drinking water facilities with GAC contactors, and at a potable reuse facility using ozone, biological filtration (BAF), ultrafiltration, GAC, and UV to meet treatment goals. Samples were collected at different points of GAC exhaustion.

More than 40 DBPs were measured in the pilot and full-scale samples. Extracts were prepared by solid phase extraction (SPE; Lau et al., 2021) and are being used to measure CHO cell cytotoxicity and genotoxicity based on cellular stress response in human HepG2 cells and via a high throughput toxicogenomics-based yeast assay.

Resulsts from pilot testing illustrate lower calculated toxicity with chloramine compared to chlorine disinfection of pre-GAC samples with higher bromide and iodide concentrations. However, at ambient bromide and iodide concentrations, the cytotoxicity was similar in settled water samples disinfected with chloramine compared to chlorine.

GAC treatment reduced calculated cytotoxicity more than switching to chloramines, even at ~80 percent TOC breakthrough. Potable reuse treatment samples illustrated ~65% reduction in measured cytotoxicity through ozone and BAF treatment. Treatment through fresh GAC provided an additional 50% decrease in cytotoxicity.  Measured cytotoxicity, which accounts for unknown DBPs, was more important than calculated cytotoxicity based on known regulated and unregulated DBPs.