I joined Earth Sciences about 8 months ago, moving back to Waterloo from Sudbury where I worked in Klohn-Crippen's Mining Group for several years, consulting on a variety of issues related to Rock Stability Assessment and Improvement, as well as Mining and the Environment. Prior to that time, I worked for a number of years in Geological Engineering Research with the University of Toronto, CSIRO in Australia and the Geomechanics Research Centre at Laurentian University. I have also dabbled in permafrost research and highway construction and design along the way. It is a real pleasure to return to this lovely part of Ontario after 18 years away!
My career to date in mining and geological engineering has taken me all over the world to a wide variety of most fascinating projects and locations. Highlights include: travelling across Canada, Australia and Papua New Guinea to assess the current state-of-the-art in design, installation and verification of rock support utilizing cable bolts: living in Quebec for a year to design, install and conduct an underground instrumentation program at Ansil Mine: travelling to Slovakia and Greece to determine remediation techniques for mining induced ground surface subsidence.
FIGURE 3: Drilling
One of the most interesting and exotic projects included two trips to Zimbabwe, funded by IDRC, to assess the support practices employed by small-scale co-operative chromite miners. Located in tabular lenses along the Great Dyke of Zimbabwe (Figure 1), these rich ore deposits are located quite near to the surface, enabling these small groups of men to mine without any sophisticated equipment. The traditional mining cycle of drill, blast, muck and support (Figure 2) is illustrated in photographs accompanying this article. Drilling is completed with a hand-held and operated auger drill powered by chest action (Figure 3)! Blasting is with home-made explosives, with a 24 hour no-go interval to allow the gases to move with natural convection out of the mine as no ventilation or fans are available. This is convenient as well, as most of the rock failure (Figure 4) occurs during this time interval as well, while no one is in the mine. Mucking involves removing some of the broken waste rock in wheel barrows or human-powered small rail cars to a waste dump at the surface (Figure 5), and placing most of the waste rock along with timber props back into the previously mined area as backfill (Figure 6). Finally the thin layers of chromite (Figure 7) are lifted by hand and transported to the surface for stock-piling. While the equipment, home-made explosives, and timber prop support available to these miners is very rudimentary, the miners' productivity and progress is quite rapid as they are creating the minimum sized holes in the ground. Altogether the small-scale co-ops account for approximately half of Zimbabwe's production of chromite.
FIGURE 4: Rock Failure
At Waterloo, I am teaching both introductory and advanced Engineering Geology classes, liberally illustrated with case histories from my experience. I plan to develop graduate courses in Mining and the Environment, in Rock Engineering and in Site Investigation. My research program will include work in the areas of risk assessment, site investigation for tunnelling related to geological variability, inclusion of the costs of mine site remediation at the initial stages of mine planning, and evaluation of large-scale open pit slope stability. I am also working with Giovanni Cascante of Civil Engineering on a laboratory program to evaluate the use of geophysical techniques for locating underground mine stopes - important, because above these stopes are horizontal pillars of rock (crown pillars) which may fail without warning (as shown historically in Timmins and Cobalt).
FIGURE 5: Dumping waste rock
FIGURE 6: Backfilling mined out stopes with waste rock and timber props
FIGURE 7: Chromite Seam
