ANCHORAGE – Red Dog Mine is Alaska’s only Arctic mine. Located 106 miles north of the Arctic Circle, the mine employs close to 500 people, not including about 130 additional contracted workers.
Beneath the frozen ground at Red Dog Mine is zinc and lead. The ore is so rich it could be seen from the sky 50 years ago when a pilot flying overhead first discovered the prospect.
“It’s a world class deposit,” says Teck Community & Public Relations Manager Wayne Hall. “Other mines may be around 5 percent. Just to put it in perspective, our average grade here is right around 17 to 18.”
Extracting the mineral starts with drilling holes 25 feet deep into the rock. Two operators drill about 200 holes in a pattern before carefully lowering electronic detonators inside. The detonators are then covered with an emulsion of explosives made on site. Red Dog Mine workers began making their own explosives after 9/11, when it became increasingly difficult to have them imported.
Once the area is cleared, a blast breaks apart the ore and rocks. A rotating crew then hauls away the blasted ore in massive trucks each of which carries a load of about 100 tons.
“A lot of people say they’re huge. They’re large but they’re actually smaller than what other mines around the world have,” said heavy equipment trainer Allison Conwell, who has been working at the mine for about 10 years.
“I’ve actually trained someone that’s never driven a car before,” said Conwell.
The ore is unloaded off the trucks at the primary crusher called the gyro, the first of many steps to crush the rock until it eventually becomes as fine as talcum powder.
Zinc and lead are separated from the ore by a chemical process. Each ore is added to a bubbling mixture that draws the mineral to the surface. At this point, the product is called slurry.
A machine tightly presses the slurry to remove any excess liquid, yielding a mineral concentrate that can be driven to the port down a 52 mile road originally constructed by the state and maintained by the mine.
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