Guidelines, Standards and Best Practice for Seismic Hazard Assessment and Rockburst Risk Management in South African Mines

Abstract

Seismic monitoring, analysis and interpretation are key components of the hazard assessment and risk management system on rockburst-prone mines. The Mine Health and Safety Council commissioned a task as part of the project "Minimising the rockburst risk" (SIM050302) to review current practice on South African mines and to formulate standards, guidelines, and descriptions of best practice. Standards were set for some areas of mine seismology practice such as network design and emergency response. In other areas of practice, such as data processing, it was only possible to provide guidelines. In yet other areas of practice, such as seismic hazard assessment and risk management, most methods currently in use have not been rigorously evaluated and validated. Many methods rely, to a greater or lesser extent, on local experience and subjective judgement. Tacit knowledge still has to be translated into explicit guidelines and procedures. It is thus deemed premature to set standards, or even firm guidelines. Current practice is described, and methods to evaluate the procedures are proposed.

Seismic monitoring strategies for deep longwall coal mines.

“…By the year 2000, research and monitoring efforts moved away from prediction and more toward hazard assessment and risk management. Recognizing that high-quality data are needed for these applications and that maintenance of a mine-wide seismic network poses significant challenges, many mining companies are now choosing to outsource some or all of their monitoring operations [Durrheim et al 2007].…”

“…Monitoring objectives directly related to reducing the impact of rockbursts have been established through decades of seismic monitoring in hardrock mines [e. g., Mendecki et al 1999;Durrheim et al 2007], and could be extended to coal mining. These objectives are described in the following subsections:…”

“…Following the Crandall Canyon Mine (Utah) collapse in 2007 with nine fatalities [Gates et al 2008], questions were raised about the potential benefits of applying seismic/microseismic monitoring technology to improve mine safety in deep underground coal mines, where deep is defined as several hundred meters or more of overburden. The underground mining industry's widespread use of seismic monitoring in deep rockburst-prone hardrock mines [Durrheim et al 2007] indicates that it has been beneficial in these applications, suggesting that it may also prove useful in addressing the problem of coal bumps (also known as coal bursts or rockbursts) and other large-scale ground instabilities such as mine collapse. A total of 13 workers in U.S. coal mines were killed by such ground failures in the ten-year period 2006-2015.…”

Progress and challenges in some areas of deep mining

“…It would appear to the writer that there is scope to further develop and apply some of these approaches. As discussed in several papers to this series of international seminars, risk-based approaches are widely used for the assessment and management of seismic risk (Durrheim et al, 2007;Hudyma et al, 2006;Pretorius, 2006).…”

Seismic Risk Management practices in metalliferous mines

“…Dedicated conferences have been held on Rockburst and Seismicity in Mines (RaSiM) since 1982. Some guidelines have been proposed for example, Durrheim et al (2007) focusing on standard and best practice in South African deep level tabular mines, and Essrich (2005), outlining suggested competencies for rock engineering practitioners in the same environment. Many of the practices applied worldwide are common to many operations, yet, there is no generally accepted process to manage seismic risks in hard rock mines.…”