One of the interesting aspects of being an engineer in the mining industry is travelling around the globe (or even) around your own country. I have been to over a dozen countries as part of my career and this only makes me a small-time traveller compared to other engineers I know. Travelling and experiencing the world is often part of the job, whether working for a junior miner, a major, a financial house, a consulting firm, or an equipment vendor. It is actually quite difficult to avoid travel if you work in mining.
Diavik Project
Recently a former colleague of mine on the Diavik Diamond Diavik project has published book that describes his life as an engineer. The book is titled Roseway: a Life of Adventure and is available on Amazon.
Its the story of John Wonnacott, a Canadian professional engineer who was involved in the construction of several projects, including the Diavik Diamond mine in Canada, a nickel smelter in China, a gold mine in Brazil, and a titanium mine in Madagascar to list a few.
John has a broad background, having conducted engineering studies in the jungles of Indonesia, the cold of Greenland, the sands of the desert, the heat of Australia, the altitude of the Andes. He has documented his engineering career in his new book.
Disclaimer: I have not yet read the book since it has only recently been published. However John has kindly sent me some excerpts that I have reprinted below to provide everyone with a sense for the content and style.
Some Excerpts
Introduction
At one time or another, I have been a professional paper-boy, forest worker, tree planter, market gardener, food processing equipment operator, lobster fisherman’s helper, commercial dragger deckhand, short-order cook, military engineering officer, computer system installer, greenhouse worker, permafrost researcher, marine oil spill cleanup specialist, pyrometallurgy researcher, garbage landfill operator, project manager, construction company general manager, regional director, open pit diamond miner, underground gold miner, corporate vice-president, design consultant, company owner, private corporation president and for 50 years, a damn good engineer. I have also been happily married to my wonderful wife Carole Anne for more than 52 years and we have 2 outstanding children. So I can add “husband”, “father” and “grandfather” to the list – but making lists like this is boring. Let me tell you my story.
Newfoundland
I remember in the late fall of that year, the company had a chance to bid on a larger project in Gros Morne National Park, Newfoundland. So our President, Frank Nolan (he was a brother to Fred Nolan, the infamous land-owner at Oak Island, by the way), decided he wanted to see the site and he chartered a Bell 106 helicopter to fly us there from Deer Lake. It was December (they say “December month” in that province) and when we got close to the Park, we ran into a sudden snow squall.
From bright sunny weather we were suddenly flying in heavy wet snow. I was sitting in the back of the chopper, with Frank sitting in the left front passenger seat. We were chatting with the pilot, via the radio headsets, when suddenly there was a loud “BEEP BEEP BEEP” sound coming from the front of the aircraft, and a number of the instrument lights started flashing. The engine had cut out – we learned later that wet snow had blocked the air intake and the engine had stalled – and we started descending pretty fast. Most people don’t realize that a helicopter will glide (quite steeply, at a glide angle of about 10 to 1) provided the pilot gets the torque off the rotor and he makes the correct feathering adjustments.
Our pilot did that instinctively and when we passed through the squall he calmly explained to us what was happening as he looked around for an open, flat spot to land. We didn’t have many options as we were flying over a densely wooded forest, with the mountains of Gros Morne and a deep fiord up ahead. But the pilot spotted a snow-covered frozen bog that was not a lot bigger than the helicopter and he put us down there as smoothly as if the engine hadn’t stopped. Maybe the deep snow cushioned our impact, because I felt nothing. But the instant we landed, Frank Nolan wrenched his door open, and he bolted out of the machine, straight ahead, in front of us.
The rotor was still spinning rapidly, and just as Frank ran ahead, the chopper settled further into the snow, tilting the machine forward in the process. With the chopper blades almost skimming the top of the snow, both the pilot and I expected Frank to be cut into pieces by the rotor, but he was just past their reach and he ran on, unaware of his narrow escape. When the spinning parts stopped, the pilot and I climbed out of the chopper to catch up with Frank. Examination of the machine showed us how the snow had plugged the air intake. The pilot cleared away the snow, and walked around the chopper once and then we took off again. We continued our aerial inspection of the National Park project and later that afternoon we flew back to Deer Lake.
Madagascar
The QMM field office In Port Dauphin, Madagascar was located near the edge of town, and I typically walked from my lodging to the office each morning when I was there, about the time when school started for the children. Typically I passed dozens and dozens of tiny bamboo huts with corrugated metal roofs, and dirt floors each about 2 meters square.
I was constantly amazed by the flocks of young boys and girls walking to school – each child aged from 6 to 15 years old, I suppose – dressed in immaculate white shirt or blouse and blue shorts or skirts. I never saw a dirty child, and how they could have kept clean clothes while living in those small crude huts was something I never could figure out. Even more amazing, were the genuine, wide smiles and frequent greeting as we passed the children: “bonjour monsieur, bonjour monsieur”.
It brings tears to my eyes even now, thinking about those children. If they were girls, they could look forward to a life expectancy of 48 years, according to the town officials we talked to. If they were boys, they could expect to live to an age of only 40 years. The perils of fishing in the ocean in dugout canoes made life even harder for the men.
The next morning, we arrived at the Astana international airport, to find that the check-in arrangements were quite different from what we were used to. Instead of checking our luggage at a desk and then walking through Security to get to our departure gate, everyone was expected to wheel their luggage and handbags through security, as the airline check-in desks were located inside.
The mechanics of rustling our luggage weren’t difficult, but as I passed through the check-point, suddenly a strange-sounding alarm went off. As the alarm rang and rang, my mind raced – what did I have in my bag that would trigger the alarm, I wondered? It didn’t help that the Security guards only spoke Russian, and they were dressed in military uniforms with ridiculously large military caps, which made them look imposing (and silly). But what began to worry me more, was that the look on the Security guards’ faces was not the usual one that happens when a piece of metal sets off an alarm. The guards looked frightened and angry, at the same time.
Fortunately for us, the commotion caught the attention of the clerks at the Turkish Airlines desk inside the terminal building, and one English-speaking fellow approached, speaking to the security guards in Russian first, then saying to us: “I speak English, may I help”? Well, he helped, but it took a while, because it turned out that a rarely used hidden nuclear radiation detector had been triggered when I came through the gate, and the guards were concerned that I had some kind of radioactive material in my suitcase.
For a moment my mind went blank, and then I remembered a card that I was carrying in my wallet. I had had a bout of prostate cancer the previous fall, and my brachytherapy treatment had involved inserting over a hundred tiny radioactive pellets in and around my prostate – designed to kill the cancer. The pellets decay naturally in a fairly short time, and by now, 9 or 10 months after my operation, I would have bet that the radioactive material had all decayed to an undetectable level. But my doctor had given me a card to carry, which explained the medical procedure, just for circumstances like this. When I pulled out the card, it was like a “Get out of Jail Free Card” from the Monopoly game. Instantly the guards’ attitudes changed from fear and suspicion, to sympathy and smiles. One of the big fellows wheeled my luggage over to the Turkish Airlines desk where the Good Samaritan clerk reverted back to his normal job of checking us in.
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Conclusion
It is one thing to briefly visit a remote project as part of a review team. It is another thing to be there as part of a design team trying to solve a problem and engineer a solution. I know of many engineers and geologists that would have similar work life experiences as part of their careers. However John has taken the initiative to write it all down.
Overburden is a generalized termed used to describe unconsolidated material encountered at a mine. It can consist of gravels, sands, silts, and clays and combinations of each. Usually overburden is not given much focus in many mining studies. Very often, the overburden as a unit, is not adequately characterized.
These are the clays most people are familiar with, i.e. a sedimentary deposit of very fine particles that have settled in a calm body of water. Normally consolidated clays are generally not a problem, other than having a high moisture content. As such, they can be very sticky in loader buckets, truck boxes, and when feeding crushers.
Clays in general consist of very fine plate like particles, as shown in this sketch. In over-consolidated clays, these particles have been flattened and tightly compressed as in the right image. The result is that the clay may be dense, have a good cross bedding shear strength, but very low shear strength along the plates. This characteristic is analogous to the lubricating properties of graphite, which is facilitated by sliding along graphite plates.
My experience with sensitive clays was at the former BHP bauxite mining operations along the northern coast of Suriname. There were Demerara clay channels up to 20m thick over top of many of their open pits. The bucketwheel excavators used for waste stripping would trigger the quick clay slope failures, sometimes resulting in the crawler tracks being buried and unfortunately also causing some worker fatalities.
I recall walking up towards a bucketwheel digging face as the machine quietly churned away. About 70 metres from the machine, we would see cracks quietly opening all around us as the ground mass was starting to initiate its flow towards the machine. Most times the bucketwheel could just sit there and dig. Instead of the machine having to advance toward the face, the face would advance towards the machine.
The formation of the diamond deposits in northern Canada often involved the explosive eruption of kimberlite pipes under bodies of water. The lakebed muds and expelled kimberlite by the eruption would collapse back into the crater, resulting in a mix of mud and kimberlite (yellow zones in the image). This muddy kimberlite could be soft, weak, and difficult to mine with underground methods.
At many tropical mining operations (west African gold projects for example) the upper bedrock has undergone weathering, resulting in the fresh rock being decomposed into saprolite. This clay-rich material can exceed 50 metres in thickness, can be fairly soft and diggable without blasting. This is an obvious mining cost benefit.
Compacted clay fill can also be used as a pond liner material for water retention ponds.
Mining has been a part of my life for as long as I can remember. Being born in Sudbury, many of my family members have been, or are currently involved, in mining through a variety of occupations, including my father who I idolized. However, I never knew my true interest in the industry until my 11th-grade technology class. I had a teacher who was passionate about the mining industry, and he created a project that involved developing a very basic mine design.
Before my first year of university, I had a summer job tramming at Macassa Mine in Kirkland Lake Ontario, which has been in production since 1933. My mentality was to get the boots on the ground and get the job done, whatever it took (with proper safety precautions of course). Using rail systems, dumping ore cars manually, jackleg drilling, etc. gave me the perspective that mining was archaic, mining was rough, and mining was only about the ounces.
To change the negative view around mining, I believe the main focal point should be electric equipment and the ability for remote operation/work. With all this newly developed technology at our fingertips, I know that future operations will be safer and more sustainable, which should be better portrayed.
Even creating a mining simulation video game where you can run through a story of being a manager, excavator/scoop operator, truck driver, etc. would get the thought of mining brought into the coming generations at a younger age. This would increase the talent pool from the more typical operator because more and more youth are getting skilled at remote operation through video games due to their increased screen time.
People get comfortable and people are afraid to leave home, so selling a career that allows for boundless flexibility in job tasks and constant stimulation while living wherever you desire could allow a shrinkage in the current technical gap.
So do I think the mining industry is archaic…. not anymore.
Firstly, I would like to thank this engineer for taking time to write out his well formed thoughts, and for allowing me to share them.
In today’s world, it is an onerous task to permit, finance, build, and operate a new mine. This is a significant achievement.
I would suggest that the three reporting categories be used instead of two, described as follows:
The DRX Drill Hole and Reporting algorithm developed by 
Often in 43-101 technical reports, when it comes to pit optimization, one is presented with the basic “NPV vs Revenue Factor (RF)” curve. That’s it.
It’s always a good idea to drill down deeper into the optimization data, even if you don’t intend to present that analysis in a final report. It will help develop an understanding of the nature of the orebody.
At the exploration stage one only has drill interval data from news releases to examine. A resource estimate may still be unavailable. The drill data can consist of long intervals of low grade or short intervals of high grade and everything in between. What does it all mean and what can it tell you?
Using information from a news release, I create a two column Excel table of highlighted intervals and assay grades. The nice thing about using intervals is that the company has provided their view of the mineable widths. If one is provided with raw 1-metre assay data you would have to make that decision, which can be a significant task. The company has already helped make those decisions.
The majority of mining projects tend to consist of either open pit only or underground only operations. However there are instances where the orebody is such that eventually the mine must transition from open pit to underground. Open pit stripping ratios can reach uneconomic levels hence the need for the change in direction.
There are several reasons why open pit and underground can be considered as two different projects within the same project.
An underground mine that uses a backfilling method will be able to dispose of some tailings underground. Conversely moving towards a larger open pit will require a larger tailings pond, larger waste dumps and overall larger footprint. This helps make the case for underground mining, particularly where surface area is restricted or local communities are anti-open pit.
Open pit and underground operations will require different skill sets from the perspective of supervision, technical, and operations. Underground mining can be a highly specialized skill while open pit mining is similar to earthworks construction where skilled labour is more readily available globally. Do local people want to learn underground mining skills? Do management teams have the capability and desire to manage both these mining approaches at the same time?
As you can see from the foregoing discussion, there are a multitude of factors playing off one another when examining the open pit to underground cross-over point. It can be like trying to mesh two different projects together.
This pessimism training started early in my career while working as a geotechnical engineer. Geotechnical engineers were always looking at failure modes and the potential causes of failure when assessing factors of safety.
When undertaking a due diligence, particularly for a major company or financier, we are not hired to tell them how great the project is. We are hired to look for fatal flaws, identify poorly based design assumptions or errors and omissions in the technical work. We are mainly looking for negatives or red flags.
It has been my experience that digging in a data room or speaking with the engineering consultants can reveal issues not identifiable in a 43-101 report. Possibly some of these issues were mentioned or glossed over in the report, but you won’t understand the full extent of the issues until digging deeper.
My hesitance in investing in some companies unfortunately can be penalizing. I may end up sitting on the sidelines while watching the rising stock price. Junior mining investors tend to be a positive bunch, when combined with good promotion can result in investors piling into a stock.
Most times the issue is something we couldn’t fully address given the level of study. We might have been forced to make best guess assumptions to move forward. The review engineers will have their opinions about what assumptions they would have used. Typically the common comment is that our assumption is too optimistic and their assumption would have been more conservative or realistic (in their view).
The background information on vertical conveying was provided to me by FKC-Lake Shore, a construction contractor that installs these systems. FKC itself does not fabricate the conveyor hardware. A link to their website is 
The FLEXOWELL®-conveyor system is capable of running both horizontally and vertically, or any angle in between. These conveyors consist of FLEXOWELL®-conveyor belts comprised of 3 components: (i) Cross-rigid belt with steel cord reinforcement; (ii) Corrugated rubber sidewalls; (iii) transverse cleats to prevent material from sliding backwards. They can handle lump sizes varying from powdery material up to 400 mm (16 inch). Material can be raised over 500 metres with reported capacities up to 6,000 tph.
Vendors have evaluated the use of vertical conveying against the use of a conventional vertical shaft hoisting. They report the economic benefits for vertical conveying will be in both capital and operating costs.
The vendors indicate the conveying system should be able to achieve heights of 700 metres. This may facilitate the use of internal shafts (winzes) to hoist ore from even greater depths in an expanding underground mine. It may be worth a look at your mine.