By Jason Mayne, mine rescue captain/co-trainer, Leeville underground mine
Editor's note: Newmont would like to hear your personal account of valuable lessons, best practices and safety reminders. Please e-mail your story ideas to goldstandard@newmont.com.
Carlin, Nevada
It often seems that the stories we hear the mining industry tell are of tragedies rather than everyday heroism. Here's one story that Newmont can be proud to share.
In mid-November 2010, Leeville underground miners reported a truck fire to mine dispatchers, who immediately followed Newmont's well-rehearsed emergency evacuation and notification plan. Four underground mine rescue and firefighting teams, mine management and federal officials were notified. Within 20 minutes, approximately 75 underground miners were evacuated and accounted for.
After my five-man team arrived, we discovered an electrical fire had started on a 30-ton haul truck, located nearly 1,500 feet below the surface. The fire spread to one of the truck's 7-foot tires, which was unreachable. With temperatures climbing close to 500 degrees Fahrenheit, the fire emitted dangerous gases and threatened ground stability.
To our advantage, the 4-foot flames had burned through a nearby polyethylene water line, which sprayed water onto part of the truck, but not to the core of the fire. Also, air and smoke exhausted up an open stope (large opening to the next level up) behind the truck making it easier for my team to see and approach the vehicle.
Our first mission was to systematically explore the area and extinguish the fire using dry chemicals. After discharging five, 20-pound extinguishers, the fire continued. We were then ordered to stop and retrieve a wheeled high-expansion foam generator, which sprays high volumes of rapidly expanding nonflammable foam to smother the fire.
We set up the generator and erected an 8-foot rubberized canvas air curtain to stop the foam from flowing away from the fire. We then spent the remainder of our nearly two and a half hours underground applying all 10 gallons of foam concentrate. But it was not enough to extinguish it. inside newmont
Frustrated and exhausted, we were returned to our fresh air base (the place where the command center and underground team coordinate), to be relieved by a second five-man team. We briefed that team's captain and the new team proceeded underground with 40 gallons of foam concentrate.
Nearly an hour later, after being completely doused in foam, the fire continued to burn because the truck's metal had grown too hot for the foam to extinguish the burning rubber.
This forced us to make a difficult choice. Typically, using water to douse the fire can be dangerous because it produces steam, which can burn the rescue team. Water also rapidly cools rock around a fire which can weaken ground conditions. But because the foam had failed, we weighed the risks and asked for permission to use water. The command center agreed and, fortunately, it took less than 30 minutes to finally put the fire out.
Normally this calls for celebration, but the second team captain noticed during a routine team check that the oxygen level of one member's breathing apparatus had dropped faster than normal. So that team immediately returned to the surface, and a fresh third team went down to put out hot spots and continue the investigation. In all, it took 30 mine rescue members wearing 4-hour re-breather apparatuses to control the fire while simultaneously mapping all conditions underground.
I was pleased to see how well we executed our response to the fire thanks to the comprehensive training and mock drills we routinely participate in. Being involved in emergency response and rescue for more than 15 years, I've witnessed many incidents. This was by far the most smoothly executed event I've seen.
This outcome goes to show that training, planning, good leadership and team work do pay off. The true success story is that no one was injured, minimal equipment was damaged, and the mine closed for only one shift.
April 18, 2011
