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Articles 1 - 30 of 266
Full-Text Articles in Civil Engineering
Elucidating The Impact Of Common Stormwater Pollutants On Antibiotic Resistance: The Role Of Heavy Metals, Nutrients, And Salts, Kassidy N. O'Malley, Patrick J. Mcnamara, Walter M. Mcdonald
Elucidating The Impact Of Common Stormwater Pollutants On Antibiotic Resistance: The Role Of Heavy Metals, Nutrients, And Salts, Kassidy N. O'Malley, Patrick J. Mcnamara, Walter M. Mcdonald
Civil and Environmental Engineering Faculty Research and Publications
Antibiotic resistance poses a significant global health threat, and the urban water cycle presents an opportunity to augment or limit the spread of antibiotic resistance. In particular, stormwater runoff has recently been revealed as a key conduit for antibiotic-resistant bacteria (ARB). The specific role of stormwater pollutants, however, on antibiotic resistance has not been isolated. Understanding the impact of specific pollutants common to stormwater could help optimize design and operation of stormwater systems for management of antibiotic resistance. The objective of this research was to establish the potential contributions of common stormwater pollutants to antibiotic resistance proliferation. Lab-scale stormwater microcosms …
Novel Respirometry Measurement And Comparison Of Monod Kinetic Constants And Methanogen Concentrations For 27 Full-Scale Anaerobic Bioreactors, Nicholas Benn, Antonio Martins, Daniel H. Zitomer
Novel Respirometry Measurement And Comparison Of Monod Kinetic Constants And Methanogen Concentrations For 27 Full-Scale Anaerobic Bioreactors, Nicholas Benn, Antonio Martins, Daniel H. Zitomer
Civil and Environmental Engineering Faculty Research and Publications
Monod kinetic coefficient values (km and Ks) as well as methanogen concentrations (Xac and Xh2) for various anaerobic bioreactors are required to gain a deeper understanding of anaerobic biotechnology. However, there are no existing, practical methods to measure or estimate these parameters or variables in typical anaerobic digester biomass that contains mixed cultures with inert organic solids. Current measurement methods rely on pure cultures developed in the laboratory. In this work, a novel respirometric method was developed and used to determine methanogen Monod parameters and active biomass concentration for samples from 27 full-scale anaerobic reactors. Differences (one to three orders …
Ac-Induced Corrosion Of Cathodically Protected Pipelines: Experimental Study And Probabilistic Modeling, Yuhan Su, Emadoddin Majdabadi Farahani, Qindan Huang, Qixin Zhou
Ac-Induced Corrosion Of Cathodically Protected Pipelines: Experimental Study And Probabilistic Modeling, Yuhan Su, Emadoddin Majdabadi Farahani, Qindan Huang, Qixin Zhou
Civil and Environmental Engineering Faculty Research and Publications
This study investigated the effects of alternating current (AC) interference on pipeline steel under cathodic protection (CP). In a simulated solution, real-time electrochemical measurements and corrosion rate analysis were conducted on two steel types (C1018 and X60) under various levels of AC interference with CP. Due to the complexity of AC-induced corrosion, relying on the shift in DC potential alone cannot accurately demonstrate the corrosion behavior in the presence of AC interference. In fact, such an approach may mislead the predictions of corrosion performance. It is observed that AC interference reduced the effectiveness of CP and increased the corrosion rate …
Peroxi-Electrocoagulation For Pfas Mitigation: The Impact Of Water Quality And Dissolved Organic Matter On Removal Pathways, Donald R. Ryan, Claire K. Baldus, Shimaa M. Kteeba, Melvin Samuel, Yin Wang, Laodong Wang, Brooke K. Mayer, Patrick J. Mcnamara
Peroxi-Electrocoagulation For Pfas Mitigation: The Impact Of Water Quality And Dissolved Organic Matter On Removal Pathways, Donald R. Ryan, Claire K. Baldus, Shimaa M. Kteeba, Melvin Samuel, Yin Wang, Laodong Wang, Brooke K. Mayer, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
The recent addition of per- and polyfluoroalkyl substances (PFAS) to the National Primary Drinking Water Regulation per- has increased the need for research on PFAS treatment technologies for water and wastewater. Electrochemical treatment processes have been widely investigated for PFAS removal. Peroxi-electrocoagulation (electrocoagulation paired with hydrogen peroxide (EC:H2O2)) was evaluated as a novel water treatment process for PFAS mitigation due to the multimechanistic removal pathways that can proceed during treatment, including chemical degradation via oxidation, and physical separation pathways such as sorption to flocs, flotation layer accumulation, and foam fractionation. This work investigated the impacts of …
Development Of A Probabilistic Interaction Rule And Failure Pressure Model For Pipelines With A Colony Of Corrosion Defects, Kiswendsida J. Kere
Development Of A Probabilistic Interaction Rule And Failure Pressure Model For Pipelines With A Colony Of Corrosion Defects, Kiswendsida J. Kere
Civil and Environmental Engineering Faculty Research and Publications
The interaction effect originating from a defect colony can pose a higher pipeline failure risk than the case when such possible interaction is not considered. Recognizing the limitations in existing models that can lead to inaccurate pipeline integrity assessment, the goal of this study is to develop a probabilistic interaction rule and predictive burst failure pressure model for pipelines with a colony of corrosion defects. First, a comprehensive database of burst failure pressure for pipes with a colony of corrosion is established that encompasses a wide range of influencing factors (e.g., spacing, defect sizes, and material properties) on the defect …
Transdisciplinary Collaborations For Advancing Sustainable And Resilient Agricultural Systems, Brooke Mayer
Transdisciplinary Collaborations For Advancing Sustainable And Resilient Agricultural Systems, Brooke Mayer
Civil and Environmental Engineering Faculty Research and Publications
Feeding the growing human population sustainably amidst climate change is one of the most important challenges in the 21st century. Current practices often lead to the overuse of agronomic inputs, such as synthetic fertilizers and water, resulting in environmental contamination and diminishing returns on crop productivity. The complexity of agricultural systems, involving plant-environment interactions and human management, presents significant scientific and technical challenges for developing sustainable practices. Addressing these challenges necessitates transdisciplinary research, involving intense collaboration among fields such as plant science, engineering, computer science, and social sciences. Five case studies are presented here demonstrating successful transdisciplinary approaches toward more …
Drying Reduces The Total Pfas Concentration In Biosolids And Alters The Pfas Profile, Patrick J. Mcnamara, Jessica Calteux, Eric Redman, Taryn Mcknight, Lynne Moss, Webster Hoener, Scott Carr, Zhongzhe Liu
Drying Reduces The Total Pfas Concentration In Biosolids And Alters The Pfas Profile, Patrick J. Mcnamara, Jessica Calteux, Eric Redman, Taryn Mcknight, Lynne Moss, Webster Hoener, Scott Carr, Zhongzhe Liu
Civil and Environmental Engineering Faculty Research and Publications
While per- and polyfluoroalkyl substances (PFAS) are not actually generated at water resource recovery facilities (WRRFs), utilities are being forced to consider PFAS in biosolids management plans due to mounting political pressure and pending regulations. Emerging thermal technologies including pyrolysis, gasification, and super critical water oxidation have garnered recent attention for PFAS destruction. Drying, however, is a conventional technology that might also be a tool for utilities to manage PFAS in biosolids, but research on the impacts of drying on PFAS in biosolids is scarce. The objective of this research was to determine how drying affected the fate of PFAS …
Use Of Wastewater Grit And Milorganite Chaff In Concrete, Carter Deinhammer
Use Of Wastewater Grit And Milorganite Chaff In Concrete, Carter Deinhammer
Master's Theses (2009 -)
Wastewater grit is a major byproduct from preliminary municipal wastewater treatment. Chaff is a collection of dried biosolids generated as a waste product from Milorganite® fertilizer production. Because landfilling is a costly and unsustainable method, the development of technologies for diverting grit from landfills to a useful product by tapping grit’s inherent values (e.g., sand and gravel) are of great interest. Chaff, consisting of fibers, provides a potential source for bolstering concrete tensile strength through internal means. This research has proposed a concept of grit and chaff additive-based concrete, an expansion of the grit-assisted patch material developed (GAP) in previous …
Phosphorus Recovery From Synthetic Stormwater Using Iron- And Slag-Amended Green Infrastructure Soils, Colin B. Wilson, Anthony J. Parolari, Brooke Mayer, Kaushik Venkiteshwaran
Phosphorus Recovery From Synthetic Stormwater Using Iron- And Slag-Amended Green Infrastructure Soils, Colin B. Wilson, Anthony J. Parolari, Brooke Mayer, Kaushik Venkiteshwaran
Civil and Environmental Engineering Faculty Research and Publications
The demand for phosphorus (P), fueled by the need for fertilizers to increase food production due to the ever-increasing population, is increasing P in the environment and diminishing global reserves of this nonrenewable resource. Stormwater runoff transports land-applied P into surrounding waterbodies. Green infrastructure (GI) soils are being engineered to target P removal from stormwater runoff. This research investigates the potential to recover P from engineered GI soils traditionally developed to remove P, contributing to the circular P economy by considering GI as a source of recoverable P. Batch experiments were conducted to determine the P removal performance of iron- …
Characterizing Phosphorus Removal And Recovery Performance Of A 3d Printed Iron-Embedded Polylactic Acid Composite, Colin B. Wilson, Anthony J. Parolari, Andrew Hiestand, Brooke K. Mayer, Allison Murray
Characterizing Phosphorus Removal And Recovery Performance Of A 3d Printed Iron-Embedded Polylactic Acid Composite, Colin B. Wilson, Anthony J. Parolari, Andrew Hiestand, Brooke K. Mayer, Allison Murray
Civil and Environmental Engineering Faculty Research and Publications
Green infrastructure (GI) has been heralded as a solution for reducing phosphorus (P) pollution through increasing stormwater runoff infiltration and improving water quality. Despite its global implementation, GI struggles to improve the effluent water quality discharged from these systems consistently. This research evaluates the P removal performance and recovery potential of iron-embedded polylactic acid (PLA) composites through a novel application of three-dimensional (3D) printed representative unit cells (RUC) that could be used to improve effluent quality in GI. The RUC required chemical oxidation to convert the embedded iron to hematite (Fe2O3) to facilitate P adsorption. Batch …
Pfas In Landfill Leachate: Practical Considerations For Treatment And Characterization, Fabrizio Sabba, Christian Kassar, Teng Zeng, Synthia P. Mallick, Leon Downing, Patrick J. Mcnamara
Pfas In Landfill Leachate: Practical Considerations For Treatment And Characterization, Fabrizio Sabba, Christian Kassar, Teng Zeng, Synthia P. Mallick, Leon Downing, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Per- and polyfluoroalkyl substances (PFAS) are widely used in consumer products and are particularly high in landfill leachate. The practice of sending leachate to wastewater treatment plants (WWTPs) is an issue for utilities that have biosolids land application limits based on PFAS concentrations. Moreover, landfills may face their own effluent limit guidelines for PFAS. The purpose of this review is to understand the most appropriate treatment technology combinations for mitigating PFAS in landfill leachate. The first objective is to understand the unique chemical characteristics of landfill leachate. The second objective is to establish the role and importance of known and …
Mitigation Of Antibiotic Resistance Using Ultraviolet Light-Emitting Diodes For Water Treatment, Nicole Heyniger, Patrick J. Mcnamara, Anthony D. Kappell, Brandon Schultz, Troy Skwor, Brooke K. Mayer
Mitigation Of Antibiotic Resistance Using Ultraviolet Light-Emitting Diodes For Water Treatment, Nicole Heyniger, Patrick J. Mcnamara, Anthony D. Kappell, Brandon Schultz, Troy Skwor, Brooke K. Mayer
Civil and Environmental Engineering Faculty Research and Publications
The presence of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment is a growing issue, which has been exacerbated by the overuse and misuse of antibiotics in health care and agricultural systems. One means of mitigating antibiotic resistance is through drinking water and wastewater treatment, specifically during disinfection processes. Ultraviolet light-emitting diodes (UV-LEDs) are an emerging disinfection technology featuring adjustable peak wavelength emissions. We assessed the use of UV-LED for treating waterborne ARB (Escherichia coli and Aeromonas hydrophila) and ARGs (intracellular and extracellular) compared to conventional low-pressure UV (LP-UV). Overall, less efficient reduction (bacterial inactivation and/or gene …
Separating The Impacts Of A Corrosion Inhibitor From Copper Corrosion Products On Antibiotic Resistance In Drinking Water, Veronika Folvarska, Maya Adelgren, Emily Lou Lamartina, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara
Separating The Impacts Of A Corrosion Inhibitor From Copper Corrosion Products On Antibiotic Resistance In Drinking Water, Veronika Folvarska, Maya Adelgren, Emily Lou Lamartina, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Antibiotic resistance is a growing threat to public health, and environmental factors, including metals in drinking water distribution systems, are increasingly recognized as contributors to the spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Zinc orthophosphate, a common corrosion inhibitor, and copper corrosion products (CuO and Cu2O) are frequently present in drinking water systems. While each has been shown to increase ARB and ARGs individually, their combined effects remain unknown. The objective of this study was to evaluate the combined impact of copper corrosion products and the corrosion inhibitor zinc orthophosphate on antibiotic resistance. Two …
Enhanced Perfluorooctanoic Acid (Pfoa) Degradation By Electrochemical Activation Of Peroxydisulfate (Pds) During Electrooxidation For Water Treatment, Melvin S. Samuel, Kadarkarai Govindan, Donald R. Ryan, Sean T. Mcbeath, Brooke K. Mayer, Patrick J. Mcnamara
Enhanced Perfluorooctanoic Acid (Pfoa) Degradation By Electrochemical Activation Of Peroxydisulfate (Pds) During Electrooxidation For Water Treatment, Melvin S. Samuel, Kadarkarai Govindan, Donald R. Ryan, Sean T. Mcbeath, Brooke K. Mayer, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Improved treatment of per- and polyfluoroalkyl substances (PFAS) in water is critically important in light of the proposed United States Environmental Protection Agency (USEPA) drinking water regulations at ng L−1 levels. The addition of peroxymonosulfate (PMS) during electrooxidation (EO) can remove and destroy PFAS, but ng L−1 levels have not been tested, and PMS itself can be toxic. The objective of this research was to test peroxydisulfate (PDS, an alternative to PMS) activation by boron-doped diamond (BDD) electrodes for perfluorooctanoic acid (PFOA) degradation. The influence of PDS concentration, temperature, and environmental water matrix effects, and PFOA concentration on PDS-EO …
Deformation Demands And Collapse Performance Of Seismically Detailed Concentrically Braced Frames, Samuel Jablonsky
Deformation Demands And Collapse Performance Of Seismically Detailed Concentrically Braced Frames, Samuel Jablonsky
Master's Theses (2009 -)
Special concentrically braced frames (SCBFs) and ordinary concentrically braced frames (OCBFs) are seismic-force-resisting systems often used in steel building construction. Previous research has shown that lower brace width-to-thickness ratios delay brace fracture during cyclic inelastic loading that is typical during moderate-to-large earthquakes. To ensure adequate seismic performance, SCBF and OCBF brace shapes are thus limited by the highly and moderately ductile width-to-thickness ratio limits, respectively, presented by the American Institute of Steel Construction Seismic Provisions for Structural Steel Buildings. To justify these limits, system-level analysis of SCBFs and OCBFs during high seismic events is needed. This study uses nonlinear response-history …
The Impact Of Pac-Loaded Polymer Membrane Thickness On Chloroform Removal And Comparison Of Solvent And Thermal Membrane Regeneration Methods, Yizhi Hou, Brooke K. Mayer
The Impact Of Pac-Loaded Polymer Membrane Thickness On Chloroform Removal And Comparison Of Solvent And Thermal Membrane Regeneration Methods, Yizhi Hou, Brooke K. Mayer
Civil and Environmental Engineering Faculty Research and Publications
Powdered activated carbon (PAC) has better adsorption performance than granular activated carbon (GAC) and is widely used in water purification. In most cases, PAC is dosed into water directly, then precipitated as sludge, and landfilled. In this study, PAC was mixed with a polymer and dissolved in dimethylformamide (DMF) solvent to form a PAC-loaded membrane, which was then tested for chloroform removal. The chloroform adsorption capacity of the PAC membrane increased with increasing membrane thickness because of higher carbon loading. However, regardless of membrane thickness, the flux of the PAC membranes was similar since flux resistance predominantly occurred at the …
The Effects Of Lead, Copper, And Iron Corrosion Products On Antibiotic Resistant Bacteria And Antibiotic Resistance Genes, Veronika Folvarska, San Marie Thomson, Zihao Lu, Maya Adelgren, Adam Schmidt, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara
The Effects Of Lead, Copper, And Iron Corrosion Products On Antibiotic Resistant Bacteria And Antibiotic Resistance Genes, Veronika Folvarska, San Marie Thomson, Zihao Lu, Maya Adelgren, Adam Schmidt, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Antibiotic resistance is a public health crisis. Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are present in drinking water distribution systems. Metals are known selective pressures for antibiotic resistance, and metallic corrosion products are found within drinking water distribution systems due to the corrosion of metal pipes. While corrosion products are a source of metals, the impact of specific corrosion products on antibiotic resistance has not been investigated. The objective of this study was to determine the impact of six corrosion products—CuO, Cu2O, Pb5(PO4)3OH, β-PbO2, Fe3O …
Environmental Drivers Impact The Accumulation And Diversity Of Antibiotic Resistance In Green Stormwater Infrastructure, Kassidy N. O'Malley, Patrick J. Mcnamara, Christopher Marshall, Emily Lou Lamartina, Thuy Duyen Lam, Numair Ali, Walter M. Mcdonald
Environmental Drivers Impact The Accumulation And Diversity Of Antibiotic Resistance In Green Stormwater Infrastructure, Kassidy N. O'Malley, Patrick J. Mcnamara, Christopher Marshall, Emily Lou Lamartina, Thuy Duyen Lam, Numair Ali, Walter M. Mcdonald
Civil and Environmental Engineering Faculty Research and Publications
Antibiotic resistance poses an urgent public health concern, with the environment playing a crucial role in the development and dissemination of resistant bacteria. There is a growing body of research indicating that stormwater is a significant source and transport vector of resistance elements. This research sought to characterize the role of green stormwater infrastructure (GSI), designed for stormwater infiltration, in accumulating and propagating antibiotic resistance in the urban water cycle. Sampling included 24 full-scale GSI systems representing three distinct types of GSI - bioswales, bioretention cells, and constructed wetlands. The results indicated that GSI soils accumulate antibiotic resistance genes (ARGs) …
Effect Of Heavy-Duty Electric Vehicles On Tire–Pavement Contact Forces, Jaime Hernandez, Angeli Jayme, Johann J. Cardenas Huaman, Imad L. Al-Qadi
Effect Of Heavy-Duty Electric Vehicles On Tire–Pavement Contact Forces, Jaime Hernandez, Angeli Jayme, Johann J. Cardenas Huaman, Imad L. Al-Qadi
Civil and Environmental Engineering Faculty Research and Publications
Electric vehicles offer higher acceleration than conventional internal combustion engines due to larger engine torque. The design and placement of battery packs in heavy-duty electric vehicles are still being optimized, as they can affect axle load distributions and consequently impact pavement analysis and design. This study presents a finite element model of a dual tire assembly considering varying load and acceleration conditions to investigate the effect of conventional and electric heavy-duty vehicles on tire–pavement contact forces. Three scenarios for battery pack locations were examined, leading to six loading conditions for both internal combustion engines and electric trucks. The resulting 3D …
Quaternary Ammonia Compounds In Disinfectant Products: Evaluating The Potential For Promoting Antibiotic Resistance And Disrupting Wastewater Treatment Plant Performance, Zihao Lu, Anna K. Mahony, William A. Arnold, Christopher Marshall, Patrick J. Mcnamara
Quaternary Ammonia Compounds In Disinfectant Products: Evaluating The Potential For Promoting Antibiotic Resistance And Disrupting Wastewater Treatment Plant Performance, Zihao Lu, Anna K. Mahony, William A. Arnold, Christopher Marshall, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Quaternary ammonium compounds (QACs) are a class of compounds that were widely used as disinfectants during the COVID-19 pandemic and continue to be used as disinfecting agents. After consumer usage, QAC concentrations are diluted in wastewater as they enter wastewater treatment plants. At sub-inhibitory concentrations, QACs may have unintended repercussions, including increased antibiotic resistance and inhibition of process performance in wastewater treatment plants. This review first summarizes how QACs inhibit bacteria and then highlights the mechanisms by which QACs can promote antibiotic resistance in general. Reported environmental concentrations of QACs are compared to concentrations that are suspected to impact antibiotic …
Verification And Validation Of Pavement Models, Jaime Hernandez, Angeli Jayme, Hasan Ozer, Eyal Levenberg, Lev Khazanovich, Emin M. Kutay
Verification And Validation Of Pavement Models, Jaime Hernandez, Angeli Jayme, Hasan Ozer, Eyal Levenberg, Lev Khazanovich, Emin M. Kutay
Civil and Environmental Engineering Faculty Research and Publications
Model development activities are increasing in pavement research and engineering applications. At the same time, there is ambiguity and a lack of consistency with regard to checking and quantifying credibility and suitability for the intended application. Specifically, usage of the terms Verification and Validation (V&V) is seen to vary across contributions. In this context, this paper was motivated by the desire to provide a best-practice reference that underlines the significance of the V&V terms, clarifies their definition, and promotes a more unified usage. Accordingly, the objective was to offer examples that introduce the V&V jargon, demonstrate basic V&V concepts and …
Stormwater Alters The Resistome Of Urban Surface Water, An Impact That Can Be Mitigated By Green Stormwater Infrastructure, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Stormwater Alters The Resistome Of Urban Surface Water, An Impact That Can Be Mitigated By Green Stormwater Infrastructure, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Antibiotic resistance poses an escalating threat to global health, with environmental reservoirs being pivotal areas of concern, as well as opportunities for potential mitigation. Stormwater systems are an important type of environmental reservoir in the urban water cycle with a dearth of research related to impacts on antibiotic resistance. In particular, there has been limited research exploring the impact of diverse antibiotic resistance genes (ARGs) carried by stormwater from various land uses on surface water, nor has there been an examination of the role played by green stormwater infrastructure (GSI) in mitigating this impact. Therefore, this study sought to elucidate …
Quaternary Ammonium Compounds (Qacs) In Wastewater Influent And Effluent Throughout The Covid-19 Pandemic, Anna K. Mahony, Patrick J. Mcnamara, William A. Arnold
Quaternary Ammonium Compounds (Qacs) In Wastewater Influent And Effluent Throughout The Covid-19 Pandemic, Anna K. Mahony, Patrick J. Mcnamara, William A. Arnold
Civil and Environmental Engineering Faculty Research and Publications
Quaternary ammonium compounds (QACs) are used in consumer and industrial products, including disinfectants. Due to the COVID-19 pandemic, disinfectant use has increased, purportedly increasing loads to wastewater treatment plants and the environment. To understand how the increased usage has affected QAC loadings to treatment plants and to determine how effectively plants remove QACs from liquid effluent that is discharged to surface and groundwaters, influent and effluent wastewater samples were collected from four treatment plants (treatment capacities < 5 MGD to > 100 MGD) for 21 months beginning in May 2020. Influent QAC concentrations were hundreds of μg/L and effluent QAC concentrations were < 1 μg/L, corresponding to an average removal of 98% from all four plants. The most prevalent QACs in influent were those used most commonly in disinfectants, specifically benzylalkyldimethylammonium compounds (BACs) and short-chain dialkyldimethylammonium compounds (DADMACs), and influent levels of these compounds were correlated with QAC sales. Prior to this study, ethylbenzylalkyldimethylammonium compounds (EtBACs) had not been studied, and they comprised 13 ± 6% of QACs in influent. While removal was high at all plants, low μg/L concentrations were still continuously discharged into the environment. For QACs with equivalent alkyl chain lengths, those with aromatic substituents (BACs and EtBACs) appear to be removed more effectively than those with only alkyl chains (DADMACs).
Integrated Tire Wear Buildup And Rainfall-Runoff Model To Simulate Tire Wear Particles In Stormwater, Matthew Dupasquier, Jaime Hernandez, Alondra Gonzalez, Cesar Aguirre, Walter M. Mcdonald
Integrated Tire Wear Buildup And Rainfall-Runoff Model To Simulate Tire Wear Particles In Stormwater, Matthew Dupasquier, Jaime Hernandez, Alondra Gonzalez, Cesar Aguirre, Walter M. Mcdonald
Civil and Environmental Engineering Faculty Research and Publications
This paper presents an approach to integrate tire wear buildup and rainfall-runoff models to simulate tire wear buildup on road surfaces and its subsequent transport in stormwater runoff events. To do so, a buildup model is presented based on vehicle kilometers traveled, vehicle type, vehicle speed, and road roughness within a watershed. This buildup model was integrated into an EPA SWMM model that simulated the runoff of tire wear particles in twelve watersheds in the San Francisco, CA bay area. Results demonstrate that tire wear particle buildup within the watersheds ranged between 0.4 and 0.51 (kg/km2) per hour. Applied to …
Peroxi-Electrocoagulation For Treatment Of Trace Organic Compounds And Natural Organic Matter At Neutral Ph, Donald R. Ryan, Patrick J. Mcnamara, Claire K. Baldus, Yin Wang, Brooke K. Mayer
Peroxi-Electrocoagulation For Treatment Of Trace Organic Compounds And Natural Organic Matter At Neutral Ph, Donald R. Ryan, Patrick J. Mcnamara, Claire K. Baldus, Yin Wang, Brooke K. Mayer
Civil and Environmental Engineering Faculty Research and Publications
Iron-based oxidation technologies can be advantageous for mitigating trace organic compounds (TOrCs) during water and wastewater treatment due to their production of hydroxyl radicals. However, iron-based oxidation often occurs at acidic pH to promote Fenton's reaction, which limits the processes' feasibility for treatment applications. This study focused on utilizing iron-electrocoagulation (EC) paired with ex situ H2O2 addition (peroxi-electrocoagulation [EC:H2O2]) to promote oxidative reactions at neutral pH conditions. The hydroxyl radical probe para-chlorobenzoic acid (pCBA) was used to gauge oxidant activity and serve as a representative TOrC. The impact of water …
Antibiotic Resistance In Urban Stormwater: A Review Of The Dissemination Of Resistance Elements, Their Impact, And Management Opportunities, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Antibiotic Resistance In Urban Stormwater: A Review Of The Dissemination Of Resistance Elements, Their Impact, And Management Opportunities, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
The public health crisis of antibiotic resistance is a growing threat across the world that is only expected to intensify in the coming years. The cycling of antibiotic resistance genes (ARGs) in the environment via urban stormwater runoff is one means by which humans are exposed to resistant bacteria as traditional gray stormwater infrastructure facilitates the transport of resistance elements into water bodies utilized by the public. In this review, existing research on the occurrence of ARGs in urban stormwater runoff is critically reviewed with the goal of determining the role of stormwater in the dissemination and development of antibiotic …
Impact Of Corrosion Inhibitors On Antibiotic Resistance, Metal Resistance, And Microbial Communities In Drinking Water, Lee K. Kimbell, Emily Lou Lamartina, Stan Kohls, Yin Wang, Ryan J. Newton, Patrick J. Mcnamara
Impact Of Corrosion Inhibitors On Antibiotic Resistance, Metal Resistance, And Microbial Communities In Drinking Water, Lee K. Kimbell, Emily Lou Lamartina, Stan Kohls, Yin Wang, Ryan J. Newton, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Corrosion inhibitors, including zinc orthophosphate, sodium orthophosphate, and sodium silicate, are commonly used to prevent the corrosion of drinking water infrastructure. Metals such as zinc are known stressors for antibiotic resistance selection, and phosphates can increase microbial growth in drinking water distribution systems (DWDS). Yet, the influence of corrosion inhibitor type on antimicrobial resistance in DWDS is unknown. Here, we show that sodium silicates can decrease antibiotic resistant bacteria (ARB) and antibiotic-resistance genes (ARGs), while zinc orthophosphate increases ARB and ARGs in source water microbial communities. Based on controlled bench-scale studies, zinc orthophosphate addition significantly increased the abundance of ARB …
Impact Of Traffic On Air Pollution In A Mid-Sized Urban City During Covid-19 Lockdowns, Nathan Hay, Otito Onwuzurike, Somesh Roy, Patrick J. Mcnamara, Margaret L. Mcnamara, Walter M. Mcdonald
Impact Of Traffic On Air Pollution In A Mid-Sized Urban City During Covid-19 Lockdowns, Nathan Hay, Otito Onwuzurike, Somesh Roy, Patrick J. Mcnamara, Margaret L. Mcnamara, Walter M. Mcdonald
Civil and Environmental Engineering Faculty Research and Publications
In this study, we evaluated the changes in air pollutant concentrations around Milwaukee, WI, during and after lockdown due to the COVID-19 pandemic for a period of 126 days. Measurements of particulate matter (PM1, PM2.5, and PM10), NH3, H2S, and O3 + NO2, were made on a 74-km route of arterial and highway roads from April to August 2020 using a Sniffer 4D sensor mounted to a vehicle. Traffic volume during measurement periods were estimated from smartphone-based traffic data. From lockdown (March 24, 2020–June 11, 2020) to …
Pyrolysis—A Tool In The Wastewater Solids Handling Portfolio, Not A Silver Bullet: Benefits, Drawbacks, And Future Directions, Patrick J. Mcnamara, Zhongzhe Liu, Yiran Tong, Hari Santha, Lynne Moss, Daniel Zitomer
Pyrolysis—A Tool In The Wastewater Solids Handling Portfolio, Not A Silver Bullet: Benefits, Drawbacks, And Future Directions, Patrick J. Mcnamara, Zhongzhe Liu, Yiran Tong, Hari Santha, Lynne Moss, Daniel Zitomer
Civil and Environmental Engineering Faculty Research and Publications
Pyrolysis is the process whereby carbonaceous materials, such as biosolids, are heated between 400°C and 900°C in the absence of oxygen. Three main products are generated: a solid product called biochar, a py-liquid that consists of aqueous phase and non-aqueous phase liquid, and py-gas. The biochar holds value as a beneficial soil amendment and sequesters carbon. The py-liquid is potentially hazardous and needs to be dealt with (including potentially reducing it on-site via catalysis or thermal oxidation). Py-gas can be used on-site for energy recovery. Pyrolysis has gained recent interest due to concern over per- and polyfluoroalkyl substances (PFAS) in …
An Inexpensive, Reproducible Method To Quantify Activated Sludge Foaming Potential: Validation Through Lab-Scale Studies And Year-Long Full-Scale Sampling Campaign, Grace K. Scarim, Emily Lou Lamartina, Kaushik Venkiteshwaran, Daniel Zitomer, Ryan J. Newton, Patrick J. Mcnamara
An Inexpensive, Reproducible Method To Quantify Activated Sludge Foaming Potential: Validation Through Lab-Scale Studies And Year-Long Full-Scale Sampling Campaign, Grace K. Scarim, Emily Lou Lamartina, Kaushik Venkiteshwaran, Daniel Zitomer, Ryan J. Newton, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Activated sludge is a conventional treatment process for biochemical oxygen demand (BOD) and total suspended solids (TSS) removal at water resource recovery facilities (WRRFs). Foaming events are a common operational issue in activated sludge and can lead to decreased treatment efficiency, maintenance issues, and potential environmental health risks. Stable foaming events are caused by biological and chemical drivers (i.e., microbes and surfactants) during the aeration process. However, foaming events are difficult to predict and quantify. We present an inexpensive and easy-to-use method that can be applied at WRRFs to quantify foaming potential. Subsequently, the method was applied over a year-long …