Monday, November 6, 2023
Angela Küpper, PhD, P.Eng, Director and Principal Geotechnical Engineer, BGC Engineering Inc.
Dr. Angela Küpper, Ph.D., P.Eng. (BC, AB, NU, NWT), F.E.I.C. has more than forty years of experience in design, construction, rehabilitation and independent reviews of earthfill dams, including tailings dams and water retention dams for power generation and water supply. She has worked throughout the Americas, Africa and Asia. Angela’s doctoral thesis was on the topic of the design and construction of tailings dams. She has been responsible for numerous dam and waste dump projects as a designer, engineer-of-record, expert consultant and independent reviewer. In the mining industry, her experience includes gold, copper, magnetite, bauxite, nickel, mixed metals, iron, coal, and oil sands.
Over the last 20 years, Angela has been retained as an independent reviewer for large water retention dams and tailings facilities and she serves on independent review boards for some of the largest global mining companies. She has been a member of the committee that updated the Canadian Dam Safety Guidelines, and more recently she was a member of the Expert Panel that authored the Global Industry Standard on Tailings Management (GISTM). She was selected as the 2011 Distinguished Lecturer of the ASCE/University of California, Berkeley where she spoke on the topic of design and performance of earth fill dams and the 2019 Distinguished Lecturer of the University of British Columbia, Geological Engineering where she spoke on risk management of tailings facilities. She was inducted in 2021 as a Fellow of the Engineering Institute of Canada Fellow for “exceptional contributions to engineering in Canada”.
Panel Discussion #1
Research and Development in Tailings and Mine Waste Management – Lessons Learned.
Tuesday, November 7, 2023
Ed McRoberts, FCAE FEIC PhD PEng Geotechnical, WSP Canada
Questions & Thoughts on Liquefied Strength of Sand: An Overview
We shall delve into a range of topics on the liquefaction of sands. The importance of the depositional environment was known to early water-supply USA dam builders in the first half of the 20th century. This is a lesson still being re-learned in tailings, and is perhaps an example of Morgenstern’s recent use of the term “embedded ignorance”. Crucial to this for many tailings types is the shoreline location as the pond is raised during upstream construction. The question of fabric or structure on the likely insitu steady state is noted, not only on a microscopic scale but also on for example underwater beach angles. The usefulness of considering shear stress densification, under controlled conditions, is presented with several examples. Thoughts on the inappropriateness of isotropic consolidation and Ko consolidation, if by that we mean a no-lateral-strain condition, are posed. Horizontal stresses will be discussed following on a recent re-quote of Jamiolkowski’s conclusion that horizontal stress measurements are the black hole of geotechnical engineering.
While the sensitivity of CPT interpretation should be well known to most, reflection on the variation of ratio of H:V stresses throughout a sand structure arguably requires consideration. Comments on the collapse surface will be made, especially vis-à-vis commentary that it is not an intrinsic property. A review of source and magnitude of uncertainties in defining parameters for design is overviewed. While brittleness has now belatedly reached most everyone’s cognitive awareness, question still need to be addressed in application of the especially in mechanisms for the typical retrogressive nature of most if not all flow failures.
Guest Speaker Luncheon – Vale’s experiences in the geotechnical and tailings field
Geraldo Paes, Corporate Geotechnical Director, Vale
Geraldo was appointed to the position of Corporate Geotechnical Director at Vale in February 2023 to lead the corporate geotechnical team, aiming to improve the tailings and dams’ governance, establish the strategy on related programs and implementing the Global Industry Standard on Tailings Management (GISTM).
He joined Vale in June 2022, after 22 years working in a global mining and metals company, with roles spanning from tailings and dams’ management, capital projects development, and joint ventures management, in different countries and cultures.
Geraldo holds a degree in Civil Engineering from the Universidade Federal Fluminense-Brazil and Executive MBA from Fundação Getulio Vargas-Brazil and Ohio State University-USA. He also attended the General Management Executive Program (Accelerated Development Programme) at London Business School-UK.
Rafael Bittar, Executive Vice President, Technical, Vale
Rafael Bittar is Vale’s technical executive vice president and chief technical officer. He has 20 years of experience in engineering and mining. He joined the company in 2019, after the B1 failure, when he was appointed to run its Geotechnical Department globally, where he made some major improvements to its model for managing tailings and dams.
Rafael has an undergraduate degree in civil engineering and geotechnics from the Mining School at Ouro Preto Federal University and MBAs from Getulio Vargas Foundation and Dom Cabral Foundation. During his career, he has worked in many positions in the areas of operations, projects, consulting, and auditing, in Brazil and other countries.
In the last 10 years, Rafael has focused on geotechnics and management of mine tailings. Before coming to Vale, he was the senior global director at Yamana Gold. He is a strong organizational leader with extensive global experience. He is also the author of numerous publications and technical presentations related to tailings disposal and risk management in tailings storage facilities.
Panel Discussion #2
New Technologies in TSF Monitoring
Wednesday, November 8, 2023
Panel Discussion #3
Trends in ESG Practice related to Tailings Management
Bjorn Weeks, P.Eng, PhD, Senior Advisor, Teck Resources Ltd.
After Closure: The Legacy of Tailings and Mine Waste
Details coming soon.