DOI https://doi.org/10.36487/ACG_rep/1905_0.2_Brown
Cite As:
Brown, BS 2019, 'What are the real risks for tailings facilities?', in J Wesseloo (ed.),
MGR 2019: Proceedings of the First International Conference on Mining Geomechanical Risk, Australian Centre for Geomechanics, Perth, pp. 21-30,
https://doi.org/10.36487/ACG_rep/1905_0.2_Brown
Abstract:
The movement towards risk-based design and operation of tailings storage facilities (TSFs) has taken place over the last few decades. The establishment of the consequence of failure of a facility is used to determine the design criteria to be used in its design. These criteria generally set the acceptable return periods for seismic and hydrologic events that the facility must accommodate. In addition, there are generally several levels of risk assessment of the design carried out to highlight technical risks that require particular attention and controls to manage. These are usually addressed in the design phase of project development.
Despite this focus on technical risk assessment at the design phases of the development of a TSF, there is still a significant number of failures occurring every year. In recent times, there have been a number of high profile TSF failures in facilities owned by major mining houses and/or located in highly regulated, first world countries. In almost every case, the investigations into the failures have been carried out by high profile, internationally recognised geotechnical engineers who have identified the technical reasons for the failure.
In many cases, it has been shown that the root causes of the failures have been a failure in governance, capital constraints, change management, independent reviews, construction supervision, operation, etc. The investigation of failures and reports to the public are almost exclusively focused on the technical cause with much less focus on what is often the underlying root cause.
A number of international mining industry groups have recognised the lack of effective governance as being a major risk that could lead to TSF failures. The Mining Association of Canada (MAC) and the International Council on Mining and Metals (ICMM) are two examples.
In this paper, the various methods for risk assessment and management are described. Non-technical risks that arise in the design and operation of TSFs are discussed and importance of good governance and continuity of its application during the full lifecycle of the facilities is emphasised.
Keywords: risk assessment, non-technical risks, tailings management, governance
References:
ANCOLD 1999, Guidelines on Tailings Dams, Australian National Committee on Large Dams, Hobart.
CDA 1999 (revised 2007 and 2013), Dam Safety Guidelines, Canadian Dam Association, Toronto.
Davies, M & Martin, T 2009, ‘Mining market cycles and tailings dam incidents’, in D Sego, M Alostaz & N Beier (eds), Proceedings of the Thirteen International Conference on Tailings and Mine Waste, University of Alberta Geotechnical Centre, Edmonton, pp. 3–14.
Foster, MA & Fell, R 1999, A Framework For Estimating The Probability Of Failure Of Embankment Dams By Internal Erosion And Piping Using Event Tree Methods, UNSW Sydney, Kensington.
ICMM 2016, Position Statement on Preventing Catastrophic Failure Of Tailings Storage Facilities, International Council on Mining & Metals, London.
ICMM 2018, Critical Control Management Implementation Guide, International Council on Mining & Metals, London.
Standards Australia 2013, SA SNZ HB 89-2013 Risk Management – Guidelines on Risk Assessment Techniques, Standards Australia, Sydney.
UNEP 2015, Awareness and Preparedness for Emergencies at the Local Level, United Nations Environment Programme, Paris.