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Kennecott's mine may be about to go under.
No, not bust. But underground. And deeper. And wider.
By doing so, the copper giant hopes to mine metals for years, perhaps decades, to come. So much for earlier predictions that the century-old pit up Bingham Canyon would run dry by 2012.
Yes, Kennecott Utah Copper is branching out into other ventures as well, bringing houses, apartments, condos, shopping centers, business parks, a college campus, even a ski resort to the Salt Lake Valley's vast west bench. But that developer turn - as Kennecott Land - hardly means the days of ore are ending.
In fact, mine manager Ted Himebaugh compares those buried ore reserves to a tooth: The cap may be nearly mined out, but the roots remain untouched and potentially massive.
"We've got big eyes," Himebaugh says. "We've looked down there and know there's a lot of stuff."
Stuff like gold, silver, molybdenum and, of course, copper.
Wider & deeper: Since 1906, Kennecott's open pit has swelled. It now is 2.5 miles wide and three-quarters of a mile deep as crews truck out 450,000 tons of rock and ore a day.
The ore, making up about a third of that haul, is processed and the waste rock dumped elsewhere. (Of note: The average ton of ore yields 12 pounds of copper.)
This mammoth undertaking has made Kennecott one of Utah's most profitable companies ever. However, the copper lining seemed to be dimming. Only three years ago the company predicted its open-pit mine would be out of ore by 2012.
Now the company is pushing that date back - way back.
The reason: It is expanding the pit to unearth ore deposits untouched in the initial plunge downward. The expansion project - dubbed "giant leap" - will add another five years to the open pit's life alone.
"We re-evaluated the open pit's life," Himebaugh says. "What if we just step back and make a giant leap on this open pit?"
The project is already under way. Crews are hauling ton after ton of rock from the east rim. The east wall will become steeper as the company pushes it back 900 feet. In addition, the expansion will allow workers to deepen the pit by another 400 feet, uncovering even more ore.
It's a big investment. Kennecott won't hit the estimated 100 million tons of ore until 2009.
Besides extracting the additional ore, the project also buys time for company officials to figure out if and how to undertake their underground mining plans, which could keep moneymaking minerals pouring from the mountain for who knows how long.
Underground: While the ore Kennecott can reach through open-pit mining is dwindling, another mountain of reserves lies directly beneath the pit.
Those untapped minerals have the company thinking of changing the way it mines. Rather than blasting the ore from the surface and scooping it up with 98-ton shovels, the company is working toward tunneling from the pit's base to reach the ore reserves.
So how much lies beneath? Company officials speculate the stash could be greater than the amount the pit has yielded to date. That total translates to more than 17 million tons of copper, 23 million ounces of gold and 190 million ounces of silver.
The prospect of turning such a cache into cash is spurring Kennecott, which posted a record $1 billion profit in 2005.
"I'm optimistic that we will" mine underground, says Dean Gehring, Kennecott's manager of resource development. "The data that we have now [show] it's a real possibility."
Trouble below: "We known open-pit mining," Gehring says. "We've been doing it for 100 years."
But plunging into underground mining? That's different.
Company bosses aren't ready to give a definite go-ahead to underground mining because they are figuring out if crews can do it logistically, safely and profitably.
"It's understanding the risk," explains Jeane Hull, Kennecott's vice president of operations, "finding a viable method to approach that reserve."
The method Kennecott is eyeing is called block-cave mining. Miners collect the ore by tunneling below the reserves and allowing gravity to pull it downward into channelized openings.
Those tunnels could burrow down to nearly sea level.
The expense of shifting from an open-pit operation to underground mining would be huge - a figure the company is still calculating. But the time for deciding is fast-approaching.
Officials plan to re-establish a mining shaft in the northern section of the pit to "prove" whether the ore roots are as immense as they suspect.
"There are two or three [other] spots we'll be going underground in the next year," Himebaugh says.
Development dreams: In the meantime, Kennecott Land - the sister corporation launched in 2001- will keep building its 14,000-home Daybreak development in South Jordan.
The 4,000-acre project is just the beginning of what could be a building bonanza. Kennecott owns 93,000 acres along the west bench, and much of that could give way to homes, condos and shopping centers in the next 50 years.
"All of our business activities can occur at the same time," says Vicki Varela, vice president of public policy for the development company.
So will the mine keep churning out gold, silver and copper that entire time - or longer?
"Who knows?" Hull says. "It's anybody's conjecture at this point."