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Research in our group recently showed that the oxidation of toxic ammonia by nitrifying bacteria can occur during winter in activated sludge wastewater treatment plants operated at low solids residence time. However, this is possible only if nitrifiers already colonized the upstream sewer system. We also demonstrated that it is the case for most municipalities in Quebec, but not in the United Kingdom. The origin and geographic dispersion of these nitrifiers are among the main questions to answer in order to adequately consider their presence in the wastewater in the design of wastewater treatment plants. The goal of the project is to map across the province the species observed in wastewater, and use computational and statistical modeling to reveal dispersion patterns. We already have a series of DNA sequencing that are ready for analysis, but we may need to produce more sequences from samples that we already have in the laboratory. Therefore, this project will be subdivided in two sections. A first series of tasks will take place in the laboratory to prepare samples for DNA sequencing. The main tasks, however, will be to use bioinformatics, and statistical modeling to analyse the geographic distribution of species. No special knowledge of statistics of bioinformatics is necessary, but interests and skills in computer programming is necessary.

Perform laboratory analyses including extraction of DNA and PCR. Perform computer programming to implements analysis using available procedure libraries.

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The epidemic of COVID-19 led to the widespread acceptance that we can quantify the circulation of a large number of infectious agents in the human population by monitoring wastewater (named wastewater-based epidemiology). Our laboratory is still producing the analyses of SARS-CoV-2 (the agent of COVID-19) in the wastewater of the four biggest cities in Quebec that are used by the public health authorities to monitor the evolution of the pandemic (). Several developments remain to be made to bring wastewater-based epidemiology to full fruition. The goal of this project is to characterize the spatial and temporal variations in the DNA sequence of SARS-CoV-2 and of the Pepper Mild Mottle Virus (PMMV, a common human fecal virus). Previous data from sampling obtained at different locations in Montreal showed an increasing bias in the recovery efficiencies of sequence information from the initial discharge to the end of the sewer system. It was hypothesized that this increasing bias in sequence information was due to differential decay in the genome. The goals of this part of the project will be to reproduce in the lab the changes in sequences recovery efficiencies of SARS-CoV-2 observed in the sewer systems. With respect to PMMV, it is believed that this virus鈥� sequences could help characterize the transport of particles in sewer systems. The goals of this part of the project will be to develop a sequencing technique for this virus.

Perform analyses of virus in wastewater using a suite of molecular (DNA or RNA based) techniques in the lab.

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The spread of antimicrobial resistance through environmental and human-associated microbes threatens to reduce the efficacy of medical treatment. One of the main sources of resistance in the environment is the release of bacteria from municipal wastewater treatment facilities. After disposal of treated wastewater and waste biosolids, the resistance genes rejected in the environment migrate back to humans via the consumption of foods and water. Therefore, tracking the various resistance genes in different environments is necessary to evaluate the risk of migration backs to humans. Our research group is developing a new approach based on PCR amplicon sequencing to achieve this with a high sensitivity. The goal of the project is to perform validation tests on the PCR primer sets that perform the detections. This will involve performing molecular manipulations in the lab. The PCR primers will then be applied to the analysis of antimicrobial resistance genes present in the microbial communities of a bioreactor simulating the human intestine and operated in our lab. Part of the project may include assistance with the operation of the bioreactor.

Perform analyses of antimicrobial resistance genes in environmental and man-made using a suite of molecular (DNA or RNA based) and chemical analysis techniques in the lab.

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In warm climates thermal stratification in hydropower reservoirs results in deoxygenation of water in the hypolimnion. Turbines withdrawing water at depth result in low dissolved oxygen (DO) in the downstream flow with a large negative impact on the downstream riverine ecosystem. Legislation (USA and elsewhere) now requires hydropower operators to guarantee meeting minimum DO limits in downstream flows. Draft tube aeration is a retrofit approach used to increase downstream DO levels not excessively impacting operation schedules. The main project aims to understand the parameters affecting aerations rates and the effectiveness of self-aerating draft tube deflectors. The SURE sub-project objective is to set up the imaging methodology and perform initial experiments (if time permits) to investigate the bubble plume formation in a cross-flow, which is a function of flow parameters. The imaging methodology will use a high-speed camera is set up to obtain images of the bubble formation. An image processing tool will be customized or developed to quantify the bubble plume characteristics. Once the tool is calibrated and validated, experiments will be performed to assess the impact of flow parameters on the bubble plume formation.

1) Design and build camera set up on experimental rig. 2) Customize or develop image analysis software for bubble plume characterization 3) Undertake preliminary experiments on bubble plume formation.

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Life cycle assessment (LCA) provides a systematic method by which environmental burdens of products and processes can be quantified from materials extraction through waste disposal (cradle颅to颅grave). An ongoing challenge exists for LCA in decision support for sustainable energy: it is temporally static and does not capture the spatial patterns of infrastructure. Present advances in LCA include how to capture spatial and temporal variations across fuel supply through end use. The Energy Technology And Policy Assessment (ETAPA) research group focuses on quantifying impacts by developing LCA methods that examine the full portfolio of energy options in support of more sustainable environmental outcomes. Critical questions remain about present energy systems, 鈥渂ridge鈥� fuels, and transition pathways. Research will focus on (1) LCA of Canadian/US energy infrastructure and (2) the question of natural gas as a transition fuel. LCA of energy infrastructure will be rapidly advancing with availability of local, national, and international datasets. To best understand the pathway to net zero, the full scope of infrastructure will inform how best to integrate solutions. The successful applicant for task (1) will focus on reviewing models and compiling energy datasets. The Global Methane Pledge was launched in 2021 at the United Nations Conference of Parties on climate change. The U.S. government must now confirm domestic emissions to quantify the life cycle emissions associated with natural gas. The successful applicant for task (2) will focus on examining models of U.S. natural gas with the opportunity to engage with scientific leaders, including U.S. national labs, non-profits, and industry.

Each student will focus on one of the two outlined research tasks and produce the noted deliverables.

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Methane is a potent greenhouse gas and reducing its emissions can substantially combat global warming in the short term. Measurements have shown that abandoned oil and gas wells are sources of methane to the atmosphere. The project involves preparing one or more field trip(s) to oil and gas-producing regions, analyzing the results in the laboratory, and conducting data analysis. Various methods including flux chambers and mobile instruments will be used to measure methane flow rates and other geochemical parameters. The findings from this study will provide quantitative data for evaluating and designing mitigation solutions for the tens of millions of abandoned oil and gas wells around the world.

Prepare for one or more field sampling trip(s), conduct field sampling, and analyze data.

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Methane is a potent greenhouse gas and reducing its emissions can substantially combat global warming in the short term. Measurements have shown that natural gas distribution, landfills, and wastewater systems are sources of methane to the atmosphere. The project involves preparing one or more field trip(s) across Montreal and in other Canadian cities, conducting field measurements, analyzing the results in the laboratory, and analyzing the data. Various methods including flux chambers and mobile instruments will be used to measure methane flow rates and other geochemical parameters. The findings from this study will provide quantitative data for evaluating and designing mitigation solutions for methane emissions from cities.

Prepare for one or more field sampling trip(s), conduct field sampling, and analyze data.

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Hydrogen emissions to the atmosphere can indirectly contribute to the greenhouse gas effect through increasing methane concentrations, tropospheric ozone concentrations, and stratospheric water vapor concentrations. However, there is a lack of in situ studies that quantify hydrogen leakage across the entire value chain. We will develop and test a hydrogen-specific emissions quantification system using controlled releases and apply the system to a site where hydrogen will be blended with natural gas and combusted. This development and demonstration will facilitate field measurements of hydrogen emissions across the value chain.

Test hydrogen emission quantification system, conduct field sampling, and analyze data.

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Per- and polyfluoroalkyl substances (PFAS) have received global public attention because of their persistence, bioaccumulation, and potential adverse effects on living organisms. Contamination of groundwater and soil by PFAS has impacted the drinking water supplies of many communities. This project aims to develop the scientific basis to assess if biological or coupled chemical-biological treatment processes can be harnessed to remove PFAS from contaminated environments cost-effectively. Students with an academic background in environmental engineering, microbiology, bioengineering, and/or biochemistry are encouraged to apply. Students will work on the enrichment of new pure and mixed bacterial cultures using bioreactors, and the phylogenetic, metabolic, and genomic characterization of the bacterial isolates and consortia of desired traits will follow successful isolation. The project requires 75% time spent in the laboratory and the rest for reading, data analysis and report preparation.

The students will be working with graduate students to cultivate and maintain microbial cultures and run biodegradation tests. Students will build membrane bioreactors and use them to develop new enrichment cultures. Students may perform phylogenetic and genomic characterization of new microbial isolates and consortia.

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Per- and polyfluoroalkyl substances (PFAS) have received global public attention because of their persistence, bioaccumulation, and potential adverse effects on living organisms. In contaminated sites, concrete has been found to be contaminated with fluorosurfactants and has become a source of long-term groundwater contamination. This project aims to develop the scientific basis for developing a remediation strategy for a large volume of contaminated concrete. Students with an academic background in civil and environmental engineering and/or chemistry are encouraged to apply. Students will work on casting concrete samples, sample preparation for chemical analysis and material characterization. Chemical uptake and leaching experiments will be performed. The project requires 75% time spent in the laboratory and the rest for reading, data analysis and report preparation.

The students will work with graduate students to prepare concrete samples, perform chemical uptake and leaching tests, and basic chemical analysis.

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The objective of the project is to develop seismic microzonation maps for the most densely populated regions of the St-Lawrence Valley where soft soil deposits are prevalent. The candidate will: - Acquire the required knowledge on seismic hazard and risk analysis. - Acquire the technical and practical knowledge on seismic methods to assess site conditions. - Organize fieldwork to record new data using a 3 components seismic sensor Tromino. - Analyze the recorded data using the HVSR method (Horizontal to Vertical Spectral Ratio) and the Geopsy庐 tool. - Update the existing microzonation map with the new data.

- Review the literature on seismic hazard and risk, non-invasive seismic methods and more particularly on HVSR. - Compile publicly available microzonation maps, boreholes and geological data - Organize field measurements at selected sites using the seismic sensor Tromino. - Learning of the Geopsy software to analyse the recorded data. - Interpret new collected data in terms of Vs30 and update existing zonation map.

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Calculate expected losses in the event of a scenario involving a fault rupture in the vicinity of the St-Lawrence Valley. The candidate will: - Acquire knowledge on seismic hazard and risk analysis. - Acquire technical knowledge on OpenQuake and the estimation of seismic losses. - Develop data bases on population and buildings for targeted areas in the St-Lawrence Valley. - Define an earthquake scenario by considering potential rupture faults and seismicity around the investigated region. - Calculate losses for this scenario and compare the results to those for a point source scenario.

- Reading of literature on the topics of seismic hazard and risk. - Training of OpenQuake - Inputting data into OpenQuake. - Compute losses for the selected earthquake fault rupture scenario using fault and point sources.

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This project aims at creating a database of fracture patterns of brittle materials under controlled static and impact loading, for supporting numerical modelling studies. Ceramic, concrete, masonry and glass specimens will be tested in the lab and subjected to various boundary and loading conditions. To this end, a new impact test setup will also be developed in collaboration with our industry partners.

1- design and test, with the assistance of a MSc student, an impact loading apparatus 2- test the materials in the lab using existing and new testing machines 3- post-process lab data

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As a result of the complex dynamics and unique events caused by COVID-19, there is consensus that teaching and learning core engineering courses in the post-pandemic era will be different for both students and instructors. But how different? What pandemic-adapted teaching strategies should be retained? What ones can be discarded? What new pedagogical components should be added? What are students expecting? What can instructors realistically offer? In the framework of a larger ongoing study, this project aims at collecting, processing and interpreting new and existing data retrieved through surveys and interviews recently conducted at 91社区 to inform the development of evidence-informed and community-based undergraduate engineering education for the new post-pandemic normal.

1- Post-process existing data from surveys and interviews 2- Create new survey forms and get them approved by the 91社区 Ethics Board 3- Interpret post-process data to inform further steps in the larger research study

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The conventional methodology for testing of failure of rocks is through triaxial testing where a cylindrical sample is subjected to a confining cell pressure and tested to failure through application of a deviator stress. This research is a departure from the conventional approach where the sample is contained in a close fitting metallic sleeve and subjected to an axial stress. The failure stress generated through elastic confinement needs to be evaluated when fractured samples are subjected to axial compression in order to examine the hydraulic properties of the fracture under normal stersses.

1. Prepare samples of the rock 2. Test the unjacketed specimens for fracture/failure 3. Test the jacketed samples to failure. 4. Determine the elasticity and failure characteristics of the rock under confinement.

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The development of hydraulic instability or liquefaction of granular materials during fluid percolation is of interest to the study of internal erosion in dike structures during storm surges. This research project will investigate the mechanics of fluid-induced instability in selected fine grained sands and investigate the mechanics of a solid rock sample located on the surface of a granular column. The development of instability will be monitored using video recording so that this information can be used to validate advance computational modelling of hydraulically induced instabilities.

1. Assist in the construction of the one-dimensional flume. 2. Prepare granular materials and measure their permeabilities 3. Conduct hydraulic instability exeriments

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Through fifteen full-scale Ultra-High Performance Concrete (UHPC) beam tests, this summer project will investigate the flexural and shear behavior of highly-reinforced slender UHPC beams as well as develop practical design guidance. Preliminary finite element simulation results show that compared to conventional concrete beams, highly-reinforced UHPC beams can reduce the section size, material usage and self-weight by over 50% while showing higher stiffness, strength, and ductility. This reduction in material usage can reduce the embodied carbon of concrete beam by over 23%, which improves the sustainability of concrete structure. Meanwhile, the reduced self-weight will (1) lower the deadload on beams themselves as well as columns and foundations, (2) extend the economic span of building frames and bridges, (3) reduce the seismic weight and thus improve the disaster resistance of concrete infrastructure, and (4) benefit the transportation and erection of prefabricated concrete members.

The selected candidate will be responsible for (1) testing full-scale UHPC beams in the lab with various advanced instrumentation, such as digital image correlation (DIC) system (2) analyzing the results.

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This project is on the area of energy efficiency and emissions of alternative motor-vehicle technologies in urban areas. The objective of the research project is to develop vehicle-level emission models based on real-world measurements as well as to evaluate the impact of alternative vehicle technologies (hybrid vs gasoline or diesel vehicles including buses and trucks). These methods will help quantify and model the energy and emission generation of passenger and freight transportation vehicles in cities like Montreal. Through the course of this project, the student will experience and learn about the alternative vehicle technologies, emission sensing equipment, data collection methods, data preparation and modeling. Student will have a chance to enhance his/her skills in data collection and preparation, data analysis, statistics/machine learning methods, and teamwork. Student will require a basic programming skills and basic knowledge in statistics/machine learning methods (student will make use of Python, R, and QGIS).

The student鈥檚 major tasks will include: - Preparing a literature review on the fuel and technology alternatives for buses and delivery trucks in urban environments (energy efficiency and emission performance). - Helping the team with the preparation and implementation of field experiments for vehicular operation and emissions data collection using specialized sensors, - Being in charge of data cleaning, preparation and basic analysis, - Helping in the modelling or statistical analysis tasks, and preparation of reports, - Participating in team meetings and IMATS lab sessions.

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