Posts Tagged: Lesley Warren

World Water Day 2021: Focus on CivMin’s water research

Monday, March 22 is World Water Day
- this year’s theme is 
Valuing Water. 

To celebrate, we’re highlighting the incredible research our
CivMin faculty and students are leading to preserve and value water. 


Prof. Jennifer Drake is a co-researcher at the Daniel’s Geen Roof Innovation Testing Laboratory (GRIT Lab). She’s currently working on connecting a greywater system that reuses storm water to irrigate the GRIT Lab's green roof, reducing the embedded energy and carbon.

Prof. Jennifer Drake

Please describe your area of research.

My group specializes in green infrastructure and works on urban drainage issues. While focus the three big technologies: permeable pavement, green roofs and bioretention system.


What projects are you currently working on?

We’re getting ready to try to connect a greywater system to the Daniel’s Geen Roof Innovation Testing Laboratory (GRIT Lab) to re-use stormwater for irrigation. This month we’ll be tracking the water quality in the cistern before connecting the system to our green roofs in May

Daniel’s Geen Roof Innovation Testing Laboratory (GRIT Lab).

What companies/organizations are you working with? (can we name them and/or tag?)

The John H. Daniels Faculty of Architecture, The Meadoway, TRCA, STEP_TRCA, Bioroof, Gro-Bark


Who is leading this research and how many are involved (breakdown of profs, students)?

The work is connected to the DesignLIFES’ CREATE Network. I am the lead investigator of this network which includes professors at UofT, UTSC, Ryerson University, Saint Mary’s University and University of Saskatchewan. The goal of DesignLIFES is to train the next generation of living and green infrastructure professionals.


What impact do these projects have on the larger scale?

Green roofs are a great technology but require irrigation to support plant growth. Most roofs are irrigated with drinking water! By re-using stormwater, we can significantly reduce the embedded energy and carbon associated with this technology.

The Meadoway in Scarborough is a is a world-class example of innovative and forward-thinking land management. By re-introducing meadow vegetation within the Hydro corridor important ecosystem services are restored. This includes flood control, reduced urban heat island effects, urban biodiversity and, most of all, multi-functional public green space.

To read more about Prof. Drake's work visit




Drinking Water Research Group

The Drinking Water Research Group (Profs. Susan Andrews, Robert Andrews and Ron Hofmann) examines all aspects of drinking water. One area of research is in the removal of microplastics in drinking water as well as their occurrence in lakes and rivers.

From top left: Profs. Robert Andrews, Susan Andrews and Ron Hofmann

 Please describe your area(s) of research: 

  • Municipal drinking water treatment: Finding ways to address emerging contaminants and to protect the public, but more economically and effectively.
  • Examining treatment requirements to convert municipal wastewater directly into drinkable water. This is the wave of the future in many parts of the world. A lot of places are running out of water (e.g. Cape Town last year), so recycling the wastewater directly into drinking water is going to become more common. Technologically it’s feasible, it’s just very expensive, and we need to find the best and cheapest way to do it.
  • Investigating means to incorporate sustainable “green” technologies into drinking water treatment including the use of biological processes (biofiltration) in lieu of chemical addition.
  • Assessing the occurrence and removal of microplastics in drinking waters as well as their sources (lakes and rivers). A recent Toronto Star article reported, plastics in the environment are considered to be the greatest threat after global warming.
  • Optimizing treatment methods including the use of ultrafiltration membranes for some of the largest cities in Canada.


What projects are you currently working on?  

Prof. Ron Hofmann: A lot of small projects looking at how to best use current assets in Canadian drinking water treatment plants to be more effective and cheaper. Also, looking at how they might be able to address newly identified contaminants, such as PFAS or microplastics (this last one is Prof. Andrew’s work).

My own work focuses on activated carbon (the same stuff as the black charcoal in aquariums), and on using UV light to disinfect the water and to destroy chemicals. UV is relatively recent and is very cheap and effective. I have a small project on harnessing sunlight to drive photovoltaic-based UV water treatment for remote and resource-poor parts of the world.

Prof. Robert Andrews: I have major ongoing projects that examine the occurrence of microplastics in Canada as well as elsewhere in the world including Singapore. This work focuses on their removal during drinking water treatment as well as during water reuse (when converting municipal wastewater into drinking water)

Prof. Susan Andrews: My research interests are somewhat eclectic, but they generally include some aspect of the chemistry of drinking water treatment processes or distribution systems. For example, we are beginning some work on some small-scale water mains to see if we can improve the way that chlorine protects the treated water as it travels from the treatment plant to our taps.

What companies/organizations are you working with?

Many of the largest water providers in Ontario (Toronto, York, Peel, Durham, Peterborough, Barrie, London, Ontario Clean Water Agency)


Who is leading this research and how many are involved (breakdown of profs, students)? 

The three professors in the DWRG (Profs. Robert Andrews, Susan Andrews and Ron Hofmann) and approximately 30 personnel (Undergraduate students, Graduate students, Post-doctoral fellows, Research assistants).


What impact do these projects have on the larger scale? (In what way will engineering address the problems to make the world a better place?) 

Improving drinking water quality, learning more about emerging contaminants that we should address through new regulations.


To read more about the DWRG, please visit




Ground & Surface Water

Prof. Elodie Passeport’s research explores the environmental remediation of contaminated surface and groundwater, primarily working on two types of green infrastructure: Constructed wetlands and bioretention cells. Her goal is to improve the reliability of green infrastructure.

Prof. Elodie Passeport


Please describe your area of research: 

My research focuses on environmental remediation of contaminated surface- and groundwater in urban, agricultural, and industrial settings. My approach is to characterize the transfer and transformation mechanisms that govern the fate and removal of contaminants in natural and engineered aquatic environments. Human activities use thousands of chemicals that reach stormwater, wastewater, and our freshwater aquatic resources. Some of these chemicals have known impacts on human and environmental health, but many are still to be discovered or are unregulated due to lack of knowledge about their toxicity.

The goal of my research is to improve the design and implementation of remediation measures. To this end, my research seeks to evaluate the efficiency of natural attenuation in contaminated groundwater and green infrastructure. I primarily work on two types of green infrastructure: constructed wetlands and bioretention cells. In support of this goal, my research group also develops new analytical methods based on stable isotopes.

Green infrastructure is a cost-effective and energy-efficient approach to water treatment but must become more reliable before it sees widespread adoption. While in principle wetlands and bioretention cells can eliminate a significant portion of contaminants, their present-day performance is highly variable. My objective is to improve the reliability of green infrastructure by advancing our understanding of their internal processes.


What projects are you currently working on? 

There are a few exciting projects in my group on two main topics: 1) Microplastic Research and 2) Stable Isotope Analysis.

  • Microplastic research

Microplastics are small plastic particles, in the 1-5000 µm range, that are widely distributed in the environment, and whose toxicological effects are mostly unknown. In collaboration with Prof. Chelsea Rochman (Ecology and Evolutionary Biology) and Prof. Jennifer Drake, our PhD student Kelsey Smyth has conducted the first comprehensive study of microplastic fate in bioretention cells. This two-year long field work showed an 84% decrease in median microplastic concentration between the inlet and outlet of a bioretention cell. Her work showed that atmospheric deposition was a significant source of microplastics – especially microfibers – in urban stormwater, and urban stormwater was a significant pathway of microplastics to downstream aquatic ecosystems. Green stormwater infiltration systems like bioretention cells have great potential to limit this pollution.

Future research will evaluate if existing total suspended solids models can be used to characterize the fate and removal of microplastics in bioretention cells to better understand if accumulation in the cell is a significant issue.

Figure 1: graphical abstract from Smyth et al. 2021.

2) Compound Specific Isotope Analysis (CSIA)

Compound Specific Isotope Analysis (CSIA) is now an accepted diagnostic tool for identifying and quantifying the transformation of traditional contaminants, e.g., toluene and chlorobenzenes, in groundwater. My group is developing new analytical methods for stable isotope analysis of non-traditional contaminants (e.g., trace organic contaminants). We are also developing new applications of CSIA in less explored environments such as surface water.

Figure 2. CSIA to distinguish transfer and transformation mechanisms

Langping Wu, a postdoctoral fellow in my group is investigating the reaction mechanisms that govern the aqueous phototransformation of benzotriazole, a corrosion-inhibitor present in urban stormwater and wastewaters. Using stable carbon, hydrogen, and nitrogen isotope analysis, we found a pH-dependence of benzotriazole direct photolysis which can be explained by a complex contribution of different reaction mechanisms. With PhD student Suchana Shamsunnahar, we have developed a novel method for CSIA of NO2- and NH2-substituded chlorobenzenes. These are common groundwater contaminants that raised significant concern for human and ecosystem health. We are working on a complex highly contaminated industrial site in Brazil with multiple academic and private partners and have proposed a novel method based on passive integrative samplers to conduct CSIA down to very low concentrations.

Altogether, these results demonstrate the potential to use CSIA as a diagnostic tool to monitor contamination and remediation in the field.


What companies/organizations are you working with?

Microplastics work: Toronto and Region Conservation Authority (TRCA)

CSIA: Geosyntec Consultants, Corteva Agriscience


What impact do these projects have on the larger scale? (In what way will engineering address the problems to make the world a better place?) 

Cleaning up water using passive remediation solutions (green infrastructure such as bioretention cells, constructed wetlands) and developing new diagnostic tools to monitor remediation.


To read more about Prof. Elodie Passeport’s work, visit



Warren Lab

Mining, Water and Environment

Prof. Lesley Warren's research examines the largely unexplored bacteria present in mine wastes and impacted waters to generate innovative new technologies that will enhance the environmental practices of the mining industry.

Prof. Lesley Warren, Director of the Lassonde Institute of Mining

What projects are you currently working on? 

The Mining Wastewater Solutions (MWS) Project is developing better tools for reactive sulfur compounds management. Funding for this project come from our mining partners and  Genome Canada and  Ontario Research Fund - Research Excellence (ORF-RE).

My group is also leading a project to constrain sulfur risks to oxygen levels in Syncrude Canada’s first pilot wet reclamation project, Base Mine Lake (BML). Funding for this project comes from Syncrude Canada and NSERC.


What companies/organizations are you working with? 

For the MWS project, we are working with Glencore Sudbury INO, Hudbay Minerals, Rambler Metals and Mining, Ecoreg Solutions and Ecometrix Consulting Companies.

For the BML project, we are working with Syncrude Canada and COSIA.


Who is leading this research and how many are involved(breakdown of profs, students)? 

I am the Principal Investigator on both projects (both international).

For the MWS project there are three professors from three institutions, three research scientists, one field researcher, 10 students, four post-doctoral fellows and two research assistants involved. 

For the BML project there are three professors from three institutions, one field researcher, 12 students and three post-doctoral fellow involved with the project.

Researchers collecting samples

What impact do these projects have on the larger scale? (In what way will engineering address the problems to make the world a better place?) 

Mining requires huge amounts of water to extract valuable commodities and generates massive amounts of wastewater that must be cleaned according to strict environmental standards before being discharged.  This wastewater also provides an ideal habitat for microbes, and studying these can help reduce wastewater treatment costs and the environmental footprint of the mining industry.

My research focuses on identifying the microbes that occur in these contexts and how they drive changes in water quality or waste stability. These new discoveries  are leading to new models and tools that tackle the underlying root causes of potential risks to the environment.


To read more about Prof. Lesley Warren's work, visit 

Methane-converting viruses could play a role in combating climate change

Professor Lesley Warren performs environmental sampling at Syncrude Canada’s Base Mine Lake, an important location for mining-impact water research and technology development in Alberta’s Oil Sands. (Photo courtesy Lesley Warren)

In a variety of environments — lakes, soils, even mining wastewater — bacteria carry out a wide range of chemical reactions. But a new study from Professor Lesley Warren (CivMin, Lassonde Institute) and her collaborators suggests that previously unknown viruses might also play a key role. The biocatalytic power of these organisms could one day be harnessed in the fight against climate change.

The past year has demonstrated just how powerful and disruptive viruses can be, not only to our health but also risks to our social structures, economies and even our planet.

But viruses don’t only cause disease in humans; plenty of them also infect bacteria. Known as bacteriophages, or just phages, the vast majority of these viruses are poorly understood due to the challenges of growing and studying them in the lab.

However, earlier this year, a new paper in Nature outlined surprising findings from this field: the discovery that some naturally-occurring phages have very large genomes. This is in contrast to previously held understanding that because viruses rely on their host’s replication machinery to multiply, they contain very few genes.

“The discovery that these viruses have large genomes and possess potentially functional genes leads us to ask: what can these genes do?” says Warren. “What are their undiscovered capabilities? What are we underestimating about them?”

Warren and her colleagues use a technique known as metagenomics to learn about wild viruses without having to culture them directly. By extracting and studying viral genetic sequences from wastewater, soil or other media, they can learn about the biochemical processes these life forms may be able to perform.

Last month, Warren, along with Professor Jill Banfield and Dr. Lin-Xing Chen (first author) of the University of California, Berkeley, co-authored a paper in Nature Microbiology  that offers some answers.

The team sampled freshwater systems around the world, including Syncrude Canada’s Base Mine Lake, a commercial size demonstration of water capped tailings technology in northern Alberta. Owned by Syncrude Canada, Base Mine Lake serves as a research facility to test and demonstrate new tailings management technologies and to improve reclamation success outcomes for pit lakes.

Professor Warren and her collaborators conducting environmental sampling at the Base Mine Lake site. (Photo courtesy Lesley Warren)

From this location and others, the research team identified 22 large-genome phages that encode a critical gene called PmoC, which are called PmoC-phage. This PmoC gene is similar to genes present in bacteria that are capable of carrying out methane oxidation.

“Methane is a critical contributor to greenhouse gas emissions — it is 14 times more effective than CO2 at trapping heat in the atmosphere,” says Warren. “When oxidized, either by bacteria or perhaps as now as this paper identifies, viruses, it gets converted to carbon dioxide. That’s still a greenhouse gas, but it’s much less harmful than methane.”

The presence of PmoC-phage and bacteria capable of methane oxidation were strongly correlated with each other. In fact, the team determined that some of the most rapidly-growing, methane-eating bacteria were infected by three PmoC-phages at one time. These findings indicate that PmoC-phages may actually be increasing methane consumption by these bacteria.

On a fundamental level, these results provide more evidence that viruses are more than just infection vectors of other organisms — they may be important players in key environmental processes that regulate the planet.

In the future, harnessing naturally-occurring entities, such as viruses in addition to microorganisms, to change one gas into another could have important implications in the fight against climate change. This is especially true in places such as the Alberta oil sands, where methane emissions are of concern.

“Exploring these PmoC-phages in Base Mine Lake can help us design a bio-tech solution that would be cost-effective for industry, while helping fight greenhouse gas emissions and climate change,” says Warren. “Our work with Syncrude Canada over the past ten years is helping to develop research-powered solutions and technology for their real-world challenges.”

“Our analyses from not just Base Mine Lake, but other freshwater contexts globally, suggest that these PmoC-phages have the potential to impact methane consumption as well as the carbon cycle of the surrounding environments,” says Professor Banfield. “The inferences of this study expand our understanding of phage capabilities and highlight new ways for us to mitigate and modulate other aspects of our environment, perhaps in even larger contexts.”


By Rachel Wallace

Originally published in Engineering News

From between a rock and a hard place (for women) to an equitable and more profitable place for all: Why gender diversity in mining is vital to the strength and future of the industry

Mining’s “not so secret” secret
It is an accepted industry-wide truth: mining has a gender diversity issue.

The industry lags behind most other sectors in tackling this systemic problem with recent statistics showing women represent only 16 per cent of the Canadian mining workforce compared to 48 per cent of the overall Canadian workforce.

The challenge of building a gender-balanced workforce stretches from site to the boardroom. According to a 2016 PWC study, the mining industry has the lowest representation of women on boards of any other sector, including oil and gas, technology, and manufacturing. Additionally, out of the top 500 globally listed mining companies, only 8 per cent of executive officers in company leadership roles are women (

Whiffs of change
Between 2018 and 2019, mining companies such as Agnico Eagle, Barrick Gold and Newmont Goldcorp have started making strides in narrowing the gender gap. For example, in 2018, Agnico Eagle became an active participant in The International Women in Resources Mentorship Program (IWRMP), a collaboration between International Women in Mining, Women in Mining Canada and Metisphere. IWRMP connects senior global female mining leaders with mentees in a variety of occupations across the entire mining cycle. In early 2019 Barrick Gold began a certification process for gender equality at its Pueblo Viejo mine in the Dominican Republic. Newmont Goldcorp’s CEO, Gary Goldberg, pledged support for Paradigm for Parity, a global corporate initiative to achieve gender parity by 2030 and holding true to that commitment, Newmont most recently appointed three female executives after their merger with Goldcorp.  These are all important steps, however for systemic transformative change, these types of initiatives need to be happening industry wide and with clear accelerated targets to achieve parity and inclusivity.

It just makes business sense
It has been shown time and again that companies prioritizing diversity and inclusivity are 21 per cent more likely to deliver “above-average profitability” and greater long-term value with the key correlation linked to gender diverse executive teams (McKinsey).  Why might this be so? Mining companies prioritizing gender parity as a strategic objective possess a diversity of ideas, experiences, cognitive frameworks and expertise that becomes an advantage in a competitive market, e.g.  facing volatile commodity prices.  A diverse workforce is more adaptable and productive; delivering higher performance for shareholders and stakeholders (McKinsey).

Deloitte also revealed through their 2018 Global Human Capital Trends survey of mining companies, that diversity is correlated “to better performance and corporate decision-making” indicating that leaders today must prioritize corporate diversity and inclusion imperatives.

 CEO and President of Teck, Don Lindsay states, “An inclusive and diverse workforce can lead to improved health and safety performance, increased innovation and productivity, and better decision-making.”

Studies have shown that greater diversity at a company can lead to better financial performance, especially when seen at the board and senior management level (Shecter, Barbara, What’s a woman on the board worth to stock investors? About 300 bps, according to CIBC study. Financial Post, 2017). Underscoring what inclusivity delivers for better margins, a 2016 PWC study found a higher average profit margin overall (23 per cent) for mining companies with mixed gender boards, compared to the average net profit margin for the top 100 mining companies (20 per cent).

Building the Diversity Pipeline: Recruitment, retention and promotion
While the business case is clear: women in leadership is good for business – the challenge of retention reflected by the extremely  high attrition rate of mid-career female talent is a critical issue across the industry.

There have been great efforts by educational institutions like the Department of Civil and Mineral (our graduating class was 35 per cent female in 2019) and other initiatives like Vale’s Voisey’s Bay Underground Training Program (seeing 4 females of 10 incoming trainees) to attract females to the industry. However, even with increased female recruitment focus, systemic corporate barriers persist stifling women throughout the duration of their career and resulting in a ‘leaky pipeline’. This leak has been highlighted most recently through the #MeTooMining movement where  female mining professionals have come forward to voice their negative experiences on mine sites, in boardrooms and throughout the industry as well as their reasons for leaving the sector all together.

This pain point is an especially important one for an industry that requires maximum efficiency, resiliency and adaptability in order to survive and thrive. The loss of experience, competencies and decision-making skills residing in these women must be addressed with initiatives to tackle biased corporate culture.

Women face unique challenges in mining compared to their male counterparts, as a study concluded by Women in Mining Canada (Women in Mining Canada, Ramp-Up: A Study on the Status of Women in Canada’s Mining and Exploration Sector (Women in Mining Canada, February 2010). The study cited: work culture, lack of mentors, perception of their skills and work-life conflicts as some of the key barriers to female career advancement. In particular, fly-in fly-out mine sites were of concern for family planning and other life commitments the study found.

Where to start? Looking at the percentage of women at each phase of the career cycle is a productive and meaningful way for mining companies to measure the health of their workforce and identify where barriers and biases occur. Monitoring imbalances in gender pay gaps, gender-bias performance metrics, the ratio of eligible women versus promotion rates of women, or their odds of advancement compared to their male colleagues, are all ways mining companies can ensure their business operations are fully supporting and thus retaining women in the workplace.

Change comes from the top down
Transforming a culture requires commitment across an entire line of business; but mining company CEO’s dedicating efforts to this inclusivity imperative see the greatest results. Building a culture of inclusivity requires the active endorsement, sponsorship and amendment of business objectives by senior leadership.  Top executives must be the agent of change to reform the power structure and dissuade systematic unconscious bias.  Without this top-down culture shift, on-site employees will never substantively engage, and transformation will not take place. For this change, and its associated boost to company profits to happen in our lifetime, rather than at the current glacial rate of change, we need more women on boards and in leadership positions now.

 “Companies should require, not ask that executives promote, recruit and include women,” stated Cynthia Carrol the former CEO of Anglo America (2007-2013).

These concerns are gaining more traction with top mining leadership who are making both the ethical and business case for a dramatic culture shift.

Andrew Mackenzie, CEO, BHP says this about the gender parity goal at their Annual Meeting, “It will demand that we question our own biases when we make decisions, that we make our workplaces more flexible and that we challenge dated stereotypes about jobs in the resources industry.” Mr. Mackenzie recently said in an interview with the Sydney Herald, “It is about tapping “the best brains in the planet”, Mackenzie says, including younger people “who are at their most productive, their most inspirational, their most quick-thinking, their most quick-witted – we need to be attractive to them by having a modern approach to sexuality and race and inclusion. When they get here there should be absolutely no discrimination, and a sense that they can flourish.”

There had been unconscious bias in the industry and that women had been disadvantaged. In the company’s “most inclusive and diverse sites” performance is 15 per cent higher.

Around the world, countries are taking notice of the sizable deficit of female representation on boards. Though not strictly focusing on mining companies, the emphasis on gender parity through legislation associated with mandatory quotas or comply-explain regimes is sparking much debate.

While quotas can be helpful to provide measurable targets, there must be meaningful change for gender parity to take hold and transform a business. Women’s qualifications must hold equal weight to their male counterparts. The persistence of the ‘old boys network’, must make way for equitable appointments based on merits. With only 16 per cent representation in the overall workforce, women’s networks are limited, and male champions are needed to create dial-moving solutions.

The Lassonde Institute of Mining

As men, early in our career or later on in our career, we need to take every opportunity to come alongside our female colleges and support and advocate for them. We need to listen and champion for their efforts and realize it is everyone’s responsibility to make this industry welcoming to all. Having women in this sector makes us smarter and more resilient for a future where vital resources are critical.
Ian Pearce (Chair of the Board, New Gold; Director, Nexa Resources; Vice Chair, Outotec and Chair, MineSense Technologies).

Ian Pearce, an active industry advisor and champion for the Lassonde Institute, works alongside an all-women leadership team and first-ever woman director, Professor Lesley Warren, to develop a new vision for the 20-year old Institute.

Gender parity is not just seen at the L/I leadership level, but also in our top research pool of principal investigators. Over 50% of our L/I principle investigators are women. This feat, the likes of which other mining programs and institutes have not yet achieved, has been made possible by the catalyzing efforts of Dean Emerita Cristina Amon of the Faculty of Applied Science and Engineering at the University of Toronto. Her persistent championing efforts towards diversity, inclusivity and parity within the Faculty additionally supported by Department of Civil & Mineral Engineering’s chair, Professor Brent Sleep, have made this positive change possible at the Lassonde Institute.

The future of mining depends on diversity in mining
A diverse mining industry will mean a workforce that is flexible, adaptable and well prepared to tackle uncertainty. Canada’s mining sector could and should be global leaders in driving this transformative change. The facts tell us that in the process, they would gain significant competitive advantage and position themselves to reap massive rewards.


By Lesley Warren 

This article originally published in foundations magazine

Lesley Warren


Lesley Warren is the Director of the Lassonde Institute of Mining. She holds the Claudette-MacKay Lassonde Chair in Mineral Engineering.

The Lassonde Institute is continuing to expand with the addition of new Principal Investigators in emerging mining fields and new global initiatives launching this year 2019-20. Learn about our future events and updates by visiting to sign up for our community emails.

Could microbes hold the key to more environmentally friendly mines? | The Northern Miner

Prof. Lesley Warren in The Norther Miner, January 9, 2017.


Geochemist and professor Lesley Warren (right) collects water samples for geochemical analyses from a waste deposit undergoing reclamation.

Ancient microbes could offer insight on better mining wastewater strategies

This story originally appeared on U of T Engineering News.

Professor Lesley Warren (standing, at right) and her colleagues are mining the genomes of microbes that thrive in wastewater generated by the resource extraction industry. Insights into how these organisms derive energy from metals and sulphur compounds could lead to new strategies for preventing pollution and optimizing mine reclamation. (Photo courtesy Lesley Warren)

Professor Lesley Warren (standing, at right) and her colleagues are mining the genomes of microbes that thrive in wastewater generated by the resource extraction industry. Insights into how these organisms derive energy from metals and sulphur compounds could lead to new strategies for preventing pollution and optimizing mine reclamation. (Photo courtesy Lesley Warren)

Wastewater from a mine doesn’t sound like a cozy habitat, but for untold numbers of microorganisms, it’s home sweet home. A new research project led by Professor Lesley Warren (CivE) will examine how these microbes make their living by studying their genes — an insight that could help further reduce the environmental footprint of the mining industry. The $3.7-million endeavour is funded in part by Genome Canada through the Large Scale Applied Research Projects (LSARP) program.

Extracting valuable metals such as copper, nickel and gold from rocks, which typically contain only a few weight percent metals, requires substantial amounts of water. All wastewater generated must be cleaned to strict federal guidelines before it can be discharged back into the environment. It is these wastewaters that the microorganisms studied by Warren and her team thrive in.

“These wastewaters contain a variety of sulphur compounds that certain bacteria can use for energy,” says Warren, who holds the Claudette Mackay-Lassonde Chair in Mineral Engineering at U of T. “Their ability to do so evolved billions of years ago, long before more complex life arrived on the scene. If the history of Earth were a 24-hour clock, they have been around for over 23 hours, while we humans have been around for only 17 seconds.”

However, our ability to investigate these bacteria and most importantly how they are cycling these sulphur compounds, which will influence the quality of mining wastewaters, has been very limited until now. If these sulphur compounds become too concentrated, the company has to implement costly chemical treatment systems to make the water acceptable for release and avoid toxicity problems in lakes or streams downstream from the mine.

Dr. Lesley Warren is the Claudette MacKay-Lassonde Chair in Mineral Engineering within the Department of Civil Engineering.

Dr. Lesley Warren is the Claudette MacKay-Lassonde Chair in Mineral Engineering within the Department of Civil Engineering.

Warren believes that genomics can help. She has spent years travelling mine sites from Canada to South Africa to better understand the sulphur geochemistry of their wastewaters and how bacteria are implicated. “I have always preferred dirty water to clean,” she jokes.

For this project, Warren and her team will apply genomics directly in tandem with comprehensive geochemical analyses and modeling to wastewaters. She will collaborate closely with Professor Jill Banfield, a trailblazer in environmental genomics at the University of California, Berkeley, Professor Christian Baron, a microbial biochemist from the Université de Montréal, and Dr. Simon Apte, a research scientist in analytical chemistry and geochemical modeling from Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO) Land and Water in Australia, to unravel the role played by these sulphur-loving microbes in important geochemical processes affecting mining wastewaters.

“Mining companies know that microorganisms are driving these reactions, but its still a black box” says Warren. “The lack of available technologies has meant that there has been little research to determine which bacteria are doing what, which ones could serve as early warning signals, or those that could actually be used as the biological treatment itself. Most importantly, mining companies don’t know which levers to pull to control the system.”

Those levers are what Warren and her colleagues aim to identify. Informed by genomic and geochemical insights they plan to develop new tools that can help mine managers make better decisions about how to manage their wastewater. “Once we understand the microbes and how they affect wastewater geochemistry, we can pinpoint the drivers of their behaviour: Which wastewater compounds are they using? Do they like it hot? Do they like it cold? We can adjust those drivers to design new processes that do what we want them to do. Essentially we are mining the bacteria that already exist in these wastewaters as a biotechnology resource.”

With this new knowledge, mines could ensure conditions that encourage the growth of organisms that break down toxic compounds, or prevent the growth of organisms that produce those toxic compounds in the first place. The team is collaborating with three Canadian mining companies, as well as two engineering consulting firms, Advisian and Ecological and Regulatory Solutions. In addition, the Mining Association of Canada, the Ontario Mining Association and CSIRO are further supporting the project.

The project also has the endorsement of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), the leading not-for-profit technical society of professionals in the Canadian minerals, metals, materials and energy industries. CIM National Executive Director, Jean Vavrek, commented: “CIM are in full support of this exciting new project.  While genomics itself is relatively new to the mineral resource industry, it has the potential to provide significant returns and generate new areas for investment in the sector.  We consider this a flagship project and will continue to follow Dr. Warren and her team closely as they pioneer genomics research for mine wastewater characterization and possibly treatment.”

“The mining industry has driven this project from its inception because they want to reduce their environmental footprint. Harnessing the biological potential of their wastewaters will facilitate the development of such strategies to achieve this goal,” says Warren. “So many of the organisms we’re finding are new to science. The chances that we are going to find organisms that are capable of doing creative things that could be useful are very high.”

Profile: The Institute for Water Innovation

Water plays a critical role in our lives. According to the United Nations Environment Programme (UNEP) “the total usable freshwater supply for ecosystems and humans is 200,000 km3 of water, which accounts for only 0.01 per cent of all water on earth.” By 2050 global water demand is projected to increase by 50 per cent due to growing manufacturing, thermal electricity generation and domestic use.

As global water scarcity and stress persist, solutions are needed to reduce pressure on freshwater assets. Now, more than ever, a focus on innovation is necessary to combat water challenges.

The newly established Institute for Water Innovation (IWI) at the University of Toronto is poised to address these challenges. According to Mandeep Rayat, Manager of IWI, the Faculty of Applied Science & Engineering has over 30 principal investigators from all the major engineering disciplines with research interests related to water. Seven of these researchers are in the Department of Civil Engineering.

The Department of Civil Engineering is playing a key role in addressing water challenges that affect human health, economic development and political stability.

Drinking Water Research Group: Clean water for cities

The Drinking Water Research Group (from top left: Profs. Robert Andrews, Susan Andrews and Ron Hofmann) examine all aspects of drinking water, from distribution optimization to new treatment technologies.

10593281256_44f81c99b1_k (2)“People in the water industry are very passionate about public health and that’s always at the forefront of any water treatment experiments,” explains Andrews. “What we do every day affects millions of people. Our research is done quietly but it’s really important. There are strong researchers in Canada working really hard who are truly focused on the health of Canadians and those around the world.”

With over 25 ongoing projects, the DWRG typically undertakes collaborative projects examining treatment, distribution, compliance and innovation to meet future water needs. By partnering with municipalities, a broad range of issues can be examined and knowledge transferred directly to utilities, regulators and policy-makers.

Jennifer Drake: Permeable pavement, rain gardens, green roofs

Drake-photo-2Prof. Jennifer Drake is looking forward to the future when her urban-based research on permeable pavements, rain gardens and green roofs will benefit from the collaboration at the IWI. “We know that these [technologies] work, but if you put them all in one neighbourhood, how do they work together? Do they interact? Can they mitigate the impacts that urbanization traditionally has on our water resources? This is long-term research where we can see how sustained small changes can make a huge impact on urban living.”

Plans are already underway to increase opportunities for research investment and collaboration with industry partners to focus on water-related needs of private firms, whose primary issue is water remediation; mining and oil sands production require a lot of water and produce a lot of pollution, which makes water-based innovation necessary.

“We need to conduct research that looks beyond remediation and maximizes water usage,” explains Drake. “We’re trying to build U of T as a leader in water technology and sustainability and now we have something that can unite us and give us a bigger presence. We’re highlighting the water expertise by connecting mechanical, chemical and civil engineering so that we increasingly work together.”

Elodie Passeport: Harnessing wetlands to purify our water

Prof. Elodie Passeport’s research focuses on understanding the behaviour of water contaminants and testing passive water treatment system designs that optimize contaminant removal. The belief that environmental quality is a cornerstone of ecosystems and human health, helps drive her research.

14150843628_b92fe2f37e_k (2)Why are wetlands important?

Natural wetlands are important ecosystems that help control flooding, improve water quality and provide multi-species habitats. Engineered wetlands are a low-cost, low-energy alternative to conventional water treatment systems.

Is it true that wetlands help to purify water systems?

Constructed wetlands can be engineered to enhance wetlands’ natural ability to remove pollution. By using natural energies from wind, sun, soil, plants and microorganisms living in the wetlands, the water is cleaned of contaminants. Early designs used single treatment units, often a pond with plants, but resulted in varying efficiency as not all chemicals could be removed in a single unit. A wide range of conditions are required to eliminate multiple chemicals, e.g. different pH, redox or plant densities.

Current approaches use multiple treatment units, each dedicated to one removal process, such as photodegradation in open-water ponds, or biodegradation in vegetated wetlands.

What are the applications for your research? 

This research impacts storm water systems as well as municipal, industrial and agricultural wastewaters. By better characterizing the hydrological, physical, chemical and microbial processes governing contaminant levels in various passive water treatment systems, we can propose efficient, affordable and low-maintenance designs.

Brent Sleep: Cleaning up contaminated soil

Across the Canadian landscape sit thousands of forgotten sites that once housed industrial operations. These places, known as brownfields, suffer a tainted legacy of contaminated soil and groundwater that prevent their re-use and can threaten the surrounding environment.

14153165189_4ab1ceeeb6_kMost sites are contaminated by chemicals like chlorinated solvents, hydrocarbons, creosotes and coal tars, which can be difficult to remove. Just one litre of trichloroethene, a common industrial cleaner, can contaminate three million litres of groundwater. The worst aspect – these pollutants can persist for centuries in underground water sources.

Prof. Brent Sleep and his Innovative Technologies for Groundwater Remediation research team work with the Institute for Water Innovation to address this challenge. Like a medicinal cocktail designed to defeat an aggressive infection, the group is investigating the enhanced effect that combining two or more different remedial technologies can have on contaminant removal.

Individually, innovative technologies like chemical oxidation, electro-kinetics, thermal remediation, and bioremediation can remove large amounts of contaminating particles. Real-world contamination, however, is highly complex. “Partnering complementary technologies addresses site complexities,” the group writes, “targeting both areas of very high contaminant concentration and areas of low – but still toxic – concentration.”

Sleep’s work aims to make brownfield cleanup more efficient, more cost-effective and more wide-spread.

Lesley Warren: Aqueous and microbial geochemistry

The largest workforce in mining isn’t found in any field camp or office tower. They aren’t wearing safety gear or business suits. They won’t be seen or heard, but their effect on mining operations can be profound. They are naturally-occurring microbes, and they are constantly influencing the water and soil environment.

Lesley-Warren1“Bacteria are present in every aspect of mining, but we don’t fully understand the impacts they can have on water quality,” says Prof. Lesley Warren, an aqueous and microbial geochemist with the Lassonde Institute of Mining and Dept. of Civil Engineering.

Warren aims to determine the identities and roles of microbes in order to gain an understanding of the bacteria’s beneficial—and detrimental—processes. Her research enables the development of effective biological tools for water quality management with industrial applications.

“Acid mine drainage is the number one priority pollution issue for the mining industry on a global scale,” said Warren. “It refers to the creation of acidic water. When sulfide minerals are exposed to water and air, sulfuric acid is generated through a natural, microbial-driven chemical reaction.”

Better understanding of the ecology of the microorganisms that are taking part in this process will help industry alleviate – or even prevent – polluting processes from occurring in the future.

Mining’s hardest workers are too small to see

…and we need to know what they’re doing

The image that is conjured up when thinking about mining is a vast underground network of tunnels, big open pits, larger than life machinery or grease-covered workers with headlamps on. But the largest workforce out in any mining operation is the microbes that are working 24/7, constantly influencing the environment.

“Bacteria are present in every aspect of mining, but we don’t fully understand the impacts they can have on water quality,” says Professor Lesley Warren, an aqueous and microbial geochemist with the Lassonde Institute of Mining and University of Toronto’s Department of Civil Engineering.

Warren works to determine the identities and roles of microbes in order to gain an understanding of the bacteria’s beneficial—and detrimental—processes. Effective biological tools, based on Warren’s research, are being developed for industry especially related to water quality management.

Water is a necessary resource for municipalities, agriculture, manufacturing, power generation—and mining. According to a 2009 report by Statistics Canada, mining accounts for two per cent of water use in Canada. Mine operations need water for mineral processing and metal recovery, but the discharge of water used in these activities can have adverse effects on surrounding surface and groundwater systems.

Water availability is a major concern for the mining industry. Fresh, clean water is a scarce resource and industry competes with many stakeholders for access. The mining industry has made great strides to minimize its effect on water quality and waste. The industry uses environmental management strategies, monitors discharges, and recycles used water, but water pollution remains a significant concern. So minimizing water requirements, while increasing the yield of recoverable minerals, is environmentally, socially and economically responsible.

Aerial view of an arid, craggy landscape surrounding tailing ponds.

Aerial view of an arid, craggy landscape surrounding tailing ponds.

“Acid mine drainage is the number one priority pollution issue for the mining industry on a global scale,” according to Warren. “It refers to the creation of acidic water. When sulphide minerals are exposed to water and air, sulphuric acid is generated through a natural, microbial-driven chemical reaction.”

Sulphuric acid lowers the pH of water, which lowers the quality of downstream water systems and increases their dissolved metal content. It is most commonly formed through the oxidation of pyrite (iron sulphide), which produces ferric sulphate and sulphuric acid. Because the majority of metal deposits are high in sulphide minerals and mining activities increase the amount of rock surface exposed to air and water, acid mine drainage remains of great concern.

Several researchers in the Lassonde Institute work to tackle water issues in the mining industry. In addition to Warren, Professors Elizabeth Edwards and Vladimiros Papangelakis explore the industrial applications for microbial and technological processes to solve mining’s pressing water challenges.

Professor Elizabeth Edwards (Department of Chemical Engineering & Applied Chemistry) works in subsurface bioremediation and remediation. For more than 20 years, she has studied microbes in contaminated sites, looking at how micro-organisms have adapted to both aerobic and anaerobic environments. The field applications of Edwards’ research involves harnessing the power of microbial metabolic processes for detoxification. One of her first commercial projects involved using bacteria to stimulate de-chlorination of solvents in industrial sites. Now, the same strategy is being applied to other contaminants.

Edwards has worked with Professor Vladimiros Papangelakis (Department of Chemical Engineering & Applied Chemistry) on a biological wastewater treatment project for acid mine drainage. Using bioleaching—the process of using bacteria to dissolve minerals instead of chemical solutions—of pyrrhotite tailings to recover nickel and elemental sulphur, making the wastewater more benign.

The oxidation of iron and of sulphur is achieved biologically. The project uses two bioleaching approaches: one for high nickel in acidic conditions at high solids concentration and one for ultramafic concentrates (high nickel and magnesium) at a neutral pH with oxygen and nitrate. The bacterium Thiobacillus denitrificans facilitates the nickel and magnesium dissolution, sulphate production and nitrate usage. In the nascent stages, the results were a two-to-four per cent nickel extraction at pH 6, but this may be more effective at a lower pH.

Papangelakis is also working on a project using forward osmosis to desalinate water for industrial usage, which could be more efficient and cost effective than existing technologies. Brackish water—a mixture of fresh and salt water—is generally unusable by industry because the salt corrodes equipment. As a water purification technique, forward osmosis is more energy efficient, and cheaper, than reverse osmosis.

Q & A with U of T Engineering’s newest professor: Lesley Warren

Dr. Lesley Warren is the latest professor to join the Faculty as the Claudette MacKay-Lassonde Chair in Mineral Engineering within the Department of Civil Engineering.

Dr. Lesley Warren is the latest professor to join the Faculty as the Claudette MacKay-Lassonde Chair in Mineral Engineering within the Department of Civil Engineering.

This story originally appeared on U of T Engineering News.

Professor Lesley Warren joined the Department of Civil Engineering and the Lassonde Institute of Mining on Jan. 1, 2016 as the Claudette MacKay-Lassonde Chair in Mineral Engineering.

Warren is an aqueous and microbial geochemist, who has pioneered the development of integrated approaches to address key questions linked to the roles microorganisms play in geochemical cycling, with a significant focus on water quality management in mining contexts. She has an internationally recognized track record of resource sector-based integrated geochemical and microbiological investigation, and has partnered with numerous energy and mining industry leaders. She serves on the Canadian Mining Industry Research Organization (CAMIRO) Expert Geochemistry panel and Syncrude Canada’s Reclamation and End Pit Lake Science Advisory Boards.

What excites you about your research?

What’s fun, exciting, and challenging about what I do is that my research group and I are usually the first people to do it. I’ve always been interested in solving problems, and I’m quite comfortable moving between disciplines. Environmental scientists tend to be creative about applying technologies from other disciplines to our field. We adopt emerging techniques about bacteria that have been developed for public health, and we apply these latest molecular techniques to environmental bacterial research—whether it’s in a mine tailings pond or a lake in Algonquin Park. The most exciting part is how we can use this information to create practical tools. What’s come out of every research project we’ve worked on is the knowledge that bacteria are present in every context and that they’re doing things that are important to water quality, but that we don’t yet understand.

You’re an environmental scientist. How will you fit into the Faculty of Applied Science and Engineering?

I’m a geochemist by training, which is part of earth science. If we want to understand what goes on in waters and river, we have to understand the interactions of our soils and rocks with that water because they’re all reactive. My research is about fundamental discoveries, which I think is what applied science is all about. In my research, we don’t know very much about the things we need to know to expand the field. We don’t yet fully understand the role these largely undescribed bacteria play in water, and this limits our ability to develop biological tools for the mining industry. I want to understand the system, and I’ll bring together whatever suite of tools I need. Engineering in general is very practical and speaks to interdisciplinary collaboration. This is the ideal environment to work together to find solutions. My research group is on the fundamental discovery side, and now we look to engineering to develop the tools from these discoveries that can be applied to industry.

Why is green mining important to you?

I’ve always been interested in water, and over the years, it became very clear to me that I was most interested in researching dirty water and how to clean it. I think that’s because I love the outdoors, and like most Canadians, I feel a deep connection to the outdoors—we see our forests, lakes, and rivers as our heritage. Water is one of the grand challenges we face, and it’s increasingly evident that we need to do a much better job of stewarding this resource. Mining’s devastating effects on water haven’t been well appreciated. Some 70 percent of world’s mines are at risk of acid mine drainage, which is the number-one global mining pollution issue around the world—this acidic, metal-laden wastewater can really damage downstream water bodies. Every mining or resource extraction company uses water, and they produce a significant amount of dirty water. They need far better strategies for cleaning and treating that water before it’s discharged. Mining in Canada uses half of our renewable water supplies every year—that’s a significant amount of water that can be significantly degraded if it’s not treated properly. Mining companies are well aware of this, and the increasing number of sustainable mining initiatives is a testament to this.

For me, green mining is all about creating the best standard of wastewater treatment for the industry. Industry needs the tools to do a better job, and there is an enormous opportunity here for applied science. Industry has generally relied on chemical water treatment, and that sometimes works, but not always—sometimes isn’t good enough. We know that bacteria drive a lot of the processes that affect water quality, and that’s what I’m interested in.

What are you most looking forward to about your new position?

Being somewhere with mining as its core mission is thrilling. The Claudette MacKay Lassonde Chair position will help me formalize the key mining interests in my research program, and help me to build larger, more innovative collaborations with interdisciplinary members of the Lassonde Institute of Mining, the Department of Civil Engineering, and the wider engineering faculty and University of Toronto. From a personal research perspective, this is the first time I’m working within a faculty of engineering, and I look forward to discussing how my fundamental research can be developed and engineered into practical programs and solutions for industry.

Tell us something that we’d be surprised to learn about you.

My father was in the Royal Navy, so I grew up by the seas all around the world. I’ve always loved water and being in water—this is probably where my passion to study it comes from. I wanted to understand more about water and the outdoors. I learn better outdoors.

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