Monday, 7 November, 2022
Evaluation of Static Liquefaction Susceptibility – Key Outcomes of the TAILLIQ Research Project
Andy Fourie, PhD – Director, Future Tails, and Professor, School of Engineering, Civil, Environmental and Mining Engineering, University of Western Australia
Collaborator: David Reid – Research Fellow, School of Engineering, Civil, Environmental and Mining Engineering, University of Western Australia
Dr. Fourie currently serves as Director of Future Tails, and Professor of Civil and Mining Engineering at the University of Western Australia (UWA). He joined UWA in 2005, moving from the University of the Witwatersrand (Wits) in Johannesburg, South Africa, where he was the Associate Dean for Research, and leader of the Waste Impact Minimization Program. He hold a Bachelors degree in Civil Engineering and a Masters degree in Engineering, both from Wits, and a PhD in Engineering from Imperial College, London.
Dr. Fourie’s research focuses on improving practices related to the management of mining residue materials, particularly mine tailings. Active research relates to the characterization of tailings strength under static and dynamic loading and associated methods of analysis of stability. His work utilizes a range of both laboratory and field testing techniques, as well as numerical modeling. Recent work includes evaluating how to avoid generation of tailings completely by developing novel in situ extraction techniques for hard-rock ore bodies.
The TAILLIQ project started in early 2017, funded by the Australian Research Council and six multinational mining companies. Four Australian Universities participated in the project, led by the University of Western Australia.
Each of the six industry sponsors provided a tailings storage facility (TSF) as a test site. Both disturbed and undisturbed (block) samples were recovered from each site and transported back to the Australian Universities. Having six different TSFs available enabled a wide range of tailings to be tested, including gold, copper (x2), platinum, iron ore, and bauxite tailings.
The presentation summarises key findings from the laboratory testing of the tailings samples, which included triaxial, direct simple shear, and hollow cylinder tests. A range of different stress paths were followed during the loading of samples, including constant deviator stress, drained (CSD) stress path tests. Using the experimental data, an alternative suggestion for identifying the onset of static liquefaction was proposed. As illustrated in this presentation, current monitoring technologies are not capable of detecting the triggering of static liquefaction timeously.
Two large calibration chambers were used for comparing cone penetration test data with known (as prepared) state parameter values. These test data were supplemented with many tests in a smaller calibration chamber that was designed and built specifically for TAILLIQ. These latter data were used to provide an update on current industry techniques for correlating tip resistance with state parameter; the test program tested various silty sand tailings, which helps to fill a major gap in the currently available database of calibration chamber results, as these are almost exclusively based on testing of clean sands. Additionally, the TAILLIQ calibration chamber tests were almost all carried out on samples having a positive state parameter, thus helping to fill another current gap in available information. One of the large calibration chambers can impose suction-controlled boundary conditions and tests using this chamber were used to develop suggested approaches for interpretation of cone penetration test data from above the phreatic surface, i.e. in partially saturated tailings.
The organization of round robin / benchmarking exercises formed a major additional part of TAILLIQ. This included a critical state line round robin that confirmed the adequacy of current state of practice techniques (loose moist tamping, end of test freezing), and a slope stability round robin that highlighted major uncertainties that remain in the analysis of CSD triggering of slope instability.
Finally, insights gained from discrete element modelling of both the laboratory element tests and cone penetration tests provides insights into the micro-mechanical behaviour of tailings during these various tests. A novel feature of this modelling work was the development of a technique to facilitate modelling of undrained cone penetration testing, with previous discrete element modelling largely restricted to simulation of drained tests.
Tuesday, 8 November, 2022
Tailings Management Under the GISTM: Building on Our Values – Strengthening Our Governance – Improving Our Performance
Kimberly Finke Morrison, PE, RG – Sr. Director, Global Tailings Management, Newmont Corporation
Kim is the Senior Director, Global Tailings Management at Newmont’s corporate headquarters in Denver, Colorado. She is responsible for oversight of tailings and dams at Newmont’s global operations, including development of standards and guidelines, overseeing governance programs, conducting risk assessments and reviews, and leading implementation of the GISTM. As founding Chair of the Tailings and Mine Waste Committee of the Society for Mining, Metallurgy & Exploration Inc. (SME), formed in 2020, she actively works to raise awareness about responsible tailings management through programs and training and served as the managing editor for the first edition of SME’s Tailings Management Handbook: A Life-Cycle Approach, published in early 2022.
She is an active member of the ICMM’s Tailings Working Group and on the Advisory Boards for the Tailings and Industrial Waste Engineering Center (TAILENG) and EduMine. In 2020, she was named to the 100 Global Inspirational Women in Mining and received the SME President’s Individual Citation Award. In 2022, she received the Environmental Stewardship Distinguished Service Award from SME’s Environmental Division and was selected to be featured in a temporary exhibit, Pioneering the Field: Women in Mining, at the National Mining Hall of Fame and Museum in Leadville, Colorado.
Rebecca Darling – Sr. Director, Social Responsibility, Newmont Corporation
Rebecca Darling is the Senior Director, Social Responsibility for Newmont where she leads the development of strategy, standards, processes and procedures related to social and community relations for the corporation. Rebecca is a strong advocate for meaningful multi-stakeholder participation in social and economic development decision-making and working with stakeholders (government, civil society, private sector and media) to design and implement early and ongoing engagement strategies that build relationships based on trust and transparency.
Much of her career has focused on driving community and local economic development rooted in creating opportunities for host communities while cultivating meaningful relationships with stakeholders. Rebecca also teaches a graduate course she developed on strategic stakeholder engagement at Cornell University. Rebecca serves on the Board of the Rocky Mountain Micro-Finance Institute and the Advisory Board of Project C.U.R.E.
Kristin Pouw – Environmental Director, Water & Tailings, Newmont Corporation
Kristin is the Global Environmental Director in the Corporate Sustainability & External Relationship Team at Newmont Mining Corporation, headquartered in Denver, Colorado. In her role, she is responsible for providing subject matter expertise and promoting alignment with standards/strategies and targets to support environmental management and performance within her focus areas of water, tailings storage facilities and heap leach facilities, and waste rock and ore stockpiles.
Kristin is a professional engineer and prior to joining Newmont in 2021 she worked in multi-disciplinary teams to prepare water balance models and develop water management plans, review water quality data, and design and optimize water treatment processes for the mining and metals sector. Kristin holds a Bachelors of Chemical Engineering and Biosciences, a Masters of Engineering and Public Policy from McMaster University, and a Water Without Borders diploma from United Nations University – Institute for Water Environment and Health.
The Global Industry Standard on Tailings Management (GISTM), published in August 2020, elevates the importance of ESG as it pertains to tailings management, embedding social and environmental performance in each of the 15 principles. As a member of the International Council on Mining and Metals (ICMM), Newmont commits to implementation of the GISTM and is actively working toward conformance, elevating cross-functional interaction and integration. Newmont has a long history of taking a leading approach to sustainability practices. While our approach has certainly evolved over the last few decades, it is important to remind ourselves of where we came from as it gives us good perspective on who we are and where we are going with respect to our ESG journey. This presentation and panel discussion provides an overview of Newmont’s governance framework as it relates to tailings management, which builds upon our values, and highlights stories that further support the importance of integrating environmental and social performance to achieve GISTM implementation.
Wednesday, 9 November, 2022
Technical and Business Lessons Learned from a Career in Mine Tailings
Len Murray, P.Eng., P.E. – Chairman and CEO, Principal, Klohn Crippen Berger
Len Murray graduated from the University of Durham UK with a Masters in Engineering geology in 1974, worked in the UK until 1981 when he moved to join Klohn Leonoff in Calgary Alberta just in time for a major mining recession in the early 80s. Surviving a troubling time in the early 1980s, Len went with Klohn to Ok Tedi, PNG for 3 years. Len’s involvement at Ok Tedi, which continues to this day, lead to a career long association with Papua New Guinea. Using experience at Ok Tedi, Porgera, Lihir and others, Len lead the successful design and on-going construction of stable tailings and waste rock facilities at the Hidden valley mine, the first of their kind at a major mine in PNG.
In 1996, which was the start of an almost 5 year long recession, Len was appointed manager of the Klohn mining group in Vancouver and started a parallel career in management. Still very active in project work worldwide, Len became Vice president of the Klohn Crippen Berger (KCB) Mining Environmental Group in 2008 and the President of the company in 2014. He is currently CEO and Chairman of the Board. Len was awarded Fellowship in the Engineering Institute of Canada in 2020 and also a Fellowship in the UK Institution of Civil Engineers the same year.
Based experience on projects and in management of a mid-sized, tailings focused consulting company, Klohn Crippen Berger, the talk looks at what has changed in the consulting industry over an almost 50 year career. Changes in technology, business approaches, and changes in society are discussed against a background of designing safe but challenging tailings projects and the macroeconomic and societal forces that influence careers. The talk explores how limited opportunities in the 1980/90s are later seen as stimulus for career growth, while the explosion of mining opportunities post 9/11, 2001 have led to a bold assumption that the engineering and geoscience industry is recession proof. The retrospective includes a summary of changes, some career advice to younger professional and a look at what the future might hold for mid-size tailings consulting companies.