A mine rescue vehicle for the 21st century
If you wanted to sum up mining in the 21st century in a few words, they would be: deeper, longer, more complex. Technological progress and economic conditions now make it possible to dig even deeper and wider than ever before for mineral deposits like gold, iron ore, salt, and potash. Yet, this expansion also presents new challenges – rescue teams will need to navigate complex mines quickly and with enough oxygen to reach the most remote corner of a mine. The amount of breathable air that the rescuers can take with them is one of the key factors restricting the optimization of escape and rescue procedures.
One of the most innovative answers to this challenge has been deployed in the Musselwhite mine, operated by Newmont Goldcorp, in northwest Ontario. Since last fall, a new kind of mines rescue vehicle has called this site home: the MRV 9000. Its origins stem from a shared desire for mining safety and collaboration between Newmont Goldcorp, safety technology company Dräger and mining vehicle manufacturer Hermann Paus Maschinen-fabrik.
Risk identified, danger averted
“The vehicle allows safety and rescue personnel to reach even the most remote areas of a mine without being restricted by the range of their breathing apparatus,” says Markus Uchtenhagen, former safety superintendent at Newmont Goldcorp. “This not only improves safety, but also has an effect on everyday working practices and a mine’s operating costs.”
Uchtenhagen had already noticed the changing risk proﬁle of ever more sprawling mines some years ago and started to think about potential solutions.
Musselwhite has been in operation since April 1997 and is now mined at a depth of 1.2 km. In 2014, the mine produced around 278,000 oz. of gold. This yield comes with expansive growth – Musselwhite now extends across 12 km horizontally. Uchtenhagen’s research revealed that mines rescue teams quickly reach the limits of their technical capabilities when dealing with such distances. Even when travelling at a speed of 25 km/hour in good visibility, it would still take a team around 45 minutes to reach certain areas of the mine. They would have to use their Dräger BG4s (breathing apparatus) on the way there, which would provide breathable air for up to four hours, depending on use. In the worst-case scenario, they would reach the scene only to turn around again without having achieved anything, because reserves of breathing air would have reached the critical 50% mark.
“Some areas were located beyond the range of our breathing apparatus, so we had to ﬁnd an answer to this problem,” Uchtenhagen says. With this in mind, he reached out to Kent Armstong, who has worked all over the world for Dräger as a business developer in the area of mine safety solutions.
“Markus came to me to pick my brain on this problem,” says Armstrong. “He said: ‘Here’s my problem, what can we do?’”
Initially, Armstrong was stumped. “We spent about eight months throwing ideas around on paper and looking at various types of equipment and vehicles, and philosophies and specs,” he says, adding that this was a brand new hurdle for the industry. “It hadn’t been done before.”
Rescue vehicles that drive into the mine like an off-road ambulance to ﬁght ﬁres and tend to the injured are nothing new.
“Solutions of this kind have been used for a number of years. What has been missing is a vehicle with an air supply that is not dependent on the ambient air,” Armstrong explains. “In the course of our talks with Newmont Goldcorp, we discovered that the best solution consisted of a vehicle with an airtight driver’s cabin and cassette – in other words, a rescue chamber – in which a rescue team can safely travel, where the individual’s breathing apparatus is only activated once they reach the rescue site.”
In close consultation with experts at Newmont Goldcorp and Dräger’s Engineered Solutions division, Uchtenhagen and Armstrong designed an all-wheel drive rescue chamber. They also got another experienced manufacturer on board: Hermann Paus Maschinen-fabrik GmbH, a German manufacturer that specializes in mining vehicles. Two and a half years elapsed between those initial drafts and the ﬁnished vehicle.
Climbing power and Formula 1 character
With a top speed of 33 km/hour and climbing power of up to 60%, the vehicle is designed for tough underground use. It weighs around 9 metric tonnes fully loaded. The driver’s cabin and cassette are equipped with an air purging system, which supplies the crew with breathing air. The operating time is up to four hours, depending on how many people are on board – one and a half hours for the outward journey, two hours at the rescue site, and one and a half hours for the return journey.
As soon as the mines rescue team members have put on their personal breathing apparatus and left the vehicle, the airflow for the remaining team members can be turned down to save breathing air. The driver’s cabin and cassette provide space for nine people – including a rescue basket for carrying injured miners to safety.
This concept exceeds Canada’s legal requirements that stipulate a rescue team must consist of at least ﬁve people. Breathing air stored at a pressure of 6,000 psi flows from six gas cylinders in the vehicles used by Newmont Goldcorp. Here a solution was chosen that is normally only seen in Formula 1 pit stops.
“An important factor for us is the ability to restore operational readiness in the shortest possible time after returning from a call-out,” explains Uchtenhagen, describing the requirements.
As such, a hydraulic lifting system was developed that allowed the gas cylinders to be replaced by an unused set in as little as 45 minutes. The vehicle also has a gas monitoring system that measures the concentration of oxygen, nitrogen dioxide, methane, and carbon monoxide in the ambient air as well as oxygen, carbon dioxide, and carbon monoxide in the vehicle’s interior. Visual and acoustic signals indicate as soon as the levels exceed or fall below a set limit. Permanently installed thermal imaging cameras at the front and rear replace handheld models, simplifying navigating dusty or smoky environments.
Through thick and thin
Franz-Josef Paus of Hermann Paus Maschinen-fabrik explains how the colossus on wheels was built: “Each one is adapted to a customer’s requirements and the conditions of a particular mine.” All three companies had to get together at regular intervals to turn the idea into reality. “The unusually close transatlantic collaboration was a success,” Paus says. “Mine operators can bring their rescue concepts right up to date with this vehicle.”
The real challenges became evident during the planning and realization. At ﬁrst glance, according to the CEO, it was about designing a rescue chamber on wheels and mounting it on an existing vehicle body. But during the discussions on the exact design, they kept coming up against practical requirements that called for structural modiﬁcations. It turned out, for example, that the seats had to be adapted to the ergonomic needs of mines rescuers. Since the closed-circuit breathing apparatus is worn on the individual’s body, the front seats on the MRV 9000 have no backrests. Notably, the design of the doors also had to be modiﬁed to allow the rescue team to get in and out of the vehicle unimpeded. It subsequently took a handful of Paus employees 15 months to realize the ﬁnely adjusted plans.
“At the same time, it was important for us to have an initial customer on board,” says Kent Armstrong. “A vehicle of this kind costs several hundred thousand dollars, which means you can’t just build it on a trial basis and launch it onto the market in the hope that the industry takes an interest in it.”
The ﬁrst two bright yellow models of the MRV 9000 were delivered to Goldcorp in 2016 and are now on standby at the Musselwhite mine and Porcupine mine in Timmins, Ont. Denis Leduc, emergency and safety coordinator at the Musselwhite mine, quickly taught his 70-man team how to use the new vehicle. “It is an exciting new acquisition that gives us a freer hand to be able to react quickly and safely in emergency situations,” he says.
Every mine presents its own challenges
Currently there are three MRV 9000s operating in Canada, one at Musselwhite, one at Porcupine, and another at a mine in Quebec. A fourth is receiving its ﬁnishing touches and is nearing delivery. And now that the word is out, Armstrong says some companies are either designing new ramps or retroﬁtting existing ones to accommodate this type of equipment.
Initial feedback on the new rescue vehicle has been very positive, but it still needs to secure its place in the international mines rescue community, cautions Armstrong.
“It’s not about simply buying a new vehicle and being prepared for anything. It is more about incorporating it in a modern safety and rescue concept.” But, he adds: “there is now a reliable answer to the question of how mine rescue can work in the 21st century.”
Recently, the MRV had to jump into action at the Musselwhite mine. On March 29, a vehicle ﬁre occurred during the evening shift changeover. None of the mine’s 712 employees reported any injuries, but the MRV was deployed to assess the situation and ensure no one was left behind during the evacuation.
TREVOR FLYNN is project engineer, engineered solutions with Draeger Safety Canada and LE YANG XU is a marketing intern.