In 2007, CDA published a set of technical bulletins to supplement Dam Safety Guidelines. The technical bulletins suggest methodologies and procedures for use by qualified professionals as they carry out dam analyses and safety assessments.
Many publications are available that provide statements of best practice in terms of open pit slope risk management. However, to date none provide a risk model that demonstrates the risk reduction achieved for applying each of the risk management elements. This leaves the slope stability practitioner unable to analytically answer questions such as: ? How frequently should slopes be inspected? ? How frequently should prisms be read? ? Should a radar be acquired? If so, which one? ? How many monitoring systems to use? And many more. This paper applies the Venter and Hamman (2018a) temporal safety risk model to an open pit in West Africa. The paper demonstrates the use of the model to a small saprolite open pit and concludes with recommendations for slope instability registers to facilitate future back?analysis in terms of this model.
The new Technical Bulletin: Application of Dam Safety Guidelines to Mining Dams, complements the Dam Safety Guidelines re-published by CDA in 2013 by providing additional explanation of how the concepts described in the guidelines apply to mining dams. The Bulletin identifies some specific issues that should be considered during the design and safety evaluation of both tailings dams and water retention dams used in the mining industry. Available in hard copy only.
Since 2005, the ACG has published conference papers across the geotechnical mining spectrum, including: underground and open pit mining, paste and thickened tailings and mine closure. The repository aims to provide the mining geomechanics fraternity with open access, peer-reviewed conference proceedings that may assist readers to maintain and develop their skills, knowledge and capabilities.
With the intention of trying to determine the causes of major tailings dam incidents, 221 case records have been collected. Examples are given of accidents and failures, together with some examples of effective remedial measures. This Bulletin is addressed to all those involved in the design, construction, operation and closure of tailings dams.
The ever increasing complexity of decision making for dams, in compliance with the requirement of transparency and accountability, requires new approaches for economical and safe operation, for maintenance and for overall management. One of these possibilities is risk assessment. The principles of risk assessment are logical and rational, and must be taken into account by all countries when making decisions regarding dams. This bulletin is intended to encourage discussion within the profession, to move towards a widely accepted position on the role of risk assessment. It is also intended to serve as a complementary tool for engineers, project owners and regulatory authorities in order to fulfill their obligations in all areas of dam safety.
In considering the critical aspects required to improve tailings dam safety, the following subjects are addressed in this Bulletin: Corporate and Management Commitment, Education and training of company staff, Critical aspects relating to the design of a tailings dam, Critical aspects to be considered when designing for and implementing the final closure of a tailings dam, Risk management, The essential need for regular external audits and Some notes on the positive role that is played by industry regulators. The conclusion reached in the document is that diligent attention to these critical aspects will result in improved awareness and a lowering of safety incidences for tailings dams.
This bulletin provides guidance for the designers, owners, operators and regulators of tailing dams on closure considerations for design at all stages of the tailings dam. The bulletin contains three main sections with a discussion on the following topics: Sustainable Closure Principles, covering current international practice, regulations, objectives, design life and phases, financial and risk management practices as they relate to closure; Sustainable Design Considerations, covering the main aspects of physical, chemical, ecological and social stability associated with tailing dam closure; Monitoring, covering post closure and long term monitoring requirements. The document presents a range of international approaches to the subject of sustainable tailings dam closure.
Geohazards comprise a subgroup of natural hazards associated with geotechnical, hydrotechnical, tectonic, snow and ice, and geochemical processes that can pose a threat to worker and public safety, asset integrity, and asset management lifecycle cost. Like for most types of threats, the risks from geohazards can be assessed qualitatively or quantitatively and used to inform a geohazard management program. Most mining companies use risk matrices to aid in the assessment, prioritisation, communication and management of corporate risks. These matrices use standardised descriptions of likelihood and consequence to help users assess risks of negative outcomes to health, safety, the environment, assets, and reputation, and are tailored to each organisations types of risk exposure and level of risk tolerance. Geohazards and related geotechnical failures can represent low-probability, high-consequence events that plot in the highest risk zones of most corporate risk matrices. Variability in spatial and temporal probabilities for people and infrastructure exposed to geohazards can have a large influence on risk exposure, and this can be challenging to assess and communicate effectively with some risk matrices. Risk is scale-dependent: the business risk due to rockfall from a single slope along a mine access road is vastly different than the total risk due to rockfalls from all slopes along that road, yet guidance is often missing on how the risks from these scenarios should be plotted on a risk matrix. These and other pitfalls associated with use of corporate risk matrices for informed geohazard management are explored.
The Conformance Protocols help operators and independent third parties assess implementation of the Standards requirements, and ultimately to demonstrate conformance. They map to the Standards 77 requirements using 219 clear and concise criteria. Effective assessment of conformance to the Standard through ICMMs Conformance Protocols will help to demonstrate to all stakeholders that responsible practices are being applied across the tailings lifecycle.