This document provides oil sands mining operators with guidelines for the audit and assessment process consistent with the requirements set out in the Performance Management documents from COSIA. There is a requirement for a 5-year audit and assessment by an independent team of audit/assessors. Through this process, the audit and assessment team will: 1. Assess the reasonableness of the relevant plans and reports. 2. Provide an opinion as to whether the mine closure plan is realistic and the progressive management of FFT is on track to the desired closure outcome.
There are growing expectations of mining companies to operate in a more sustainable manner, with a strong business case for improving waste management and reducing environmental impacts. As the stewardship of tailings come under increasing scrutiny, decision-makers are urged to adopt a robust approach to the selection of a tailings management strategy that encompasses design for closure, and leading practices to lower the risk of catastrophic dam failures, optimise the use of resources, and mitigate environmental impacts on climate change. An integrated analysis, considering economic, environmental, social, and risk aspects of the operation can therefore provide decision-makers with balanced information to ensure the right projects proceed with an optimal business case so that the most cost-effective solution, that does not externalise costs, can be selected. However, literature review revealed that fundamental shortcomings exist within traditional evaluation approaches used for economic comparisons. This paper reports on life cycle cost analyses conducted for comparing various tailings management options under different scenarios. A conceptual case study for the disposal of gold tailings in Western Australia as a slurry, as thickened, or as filtered tailings, was considered. This was done for examining the extent to which potentially hidden costs impact on the total cost of a project. It is suggested that the proposed approach will lead to selection of a tailings management alternative that ensures sound economic, environmental, and social performance is achieved.
The Tronox KZN Sands Hillendale Mine is located in Zululand close to Richards Bay. Mining activities commenced in 2001 and the mines production came to an end in 2013. At Hillendale, dunes with a high fines content were mined to recover the valuable minerals of ilmenite Zircon and rutile. The fine fraction consisting mainly of fine clay minerals was managed by storage in a residue storage facility (RSF). Following the cessation of mining activities several actions have been implemented towards achieving mine closure. This paper will firstly give some basic background on the operation of the residue facility as part of the Hillendale Mine. Secondly the paper will focus on mine closure activities planned and implemented at the RSF. The learnings and experience gained from the Hillendale Mine will form the basis of future closure plans for RSFs operated as part of Tronoxs newly established mine at Fairbreeze.
Mount Isa Copper Operations (MICO) is one of the oldest and deepest mines in Australia, comprising the largest underground network of mine development in the world. During the early operational years, ground support, particularly surface support, was not routinely installed. Although rehabilitation in recent years has drastically reduced the amount of tunnel without support, there remain tens of kilometres of excavation with limited to no ground support installed. In addition, older development was often mined within close proximity to unfilled or partially filled stopes and vertical openings. The voids pre-date modern 3D mine plans and scanning technology. Furthermore, access to the voids to conduct scans is limited, this results in an imperfect understanding of the void sizes and proximity to accessible drives. The lack of ground support and knowledge of void status poses significant ground failure risks at MICO. A significant increase in rock related near-hit incidents occurred during the second half of 2014 and the first half of 2015. A number of these incidents had the potential to cause severe or fatal harm. The incidents triggered internal investigations that aimed at understanding and reducing the ground failure risk. The outcome of the investigations was the creation of a series of interlinked systems, namely the tunnel condition risk assessment (TCRA), mine closure areas (MCA), ground awareness training (GAT), vertical opening pillar hazard assessment and control (VOPHAC), stope void review (SVR), manual scaling crews, fall of ground database and the quality assurance/quality control management plan (QA/QC MP). The individual components of the system are specialised and simple. However, the system is comprehensive and robust. Each of the components, as well as how they interlink, is discussed within this paper. The interlinked systems and practices provide controls and have proven to be effective at reducing the ground failure risks. Although the systems were developed at MICO, they have the potential to be easily adapted and utilised at other mine sites.