Feature

Hard Rock Gold Mining
Seven Mines alumni work Colorado's only active underground gold mine, which is situated only a stone's throw from one of the first Rocky Mountain gold strikes.


The phone on the office wall is a dedicated line to the working mine hundreds of feet below our feet. When it jangled to life during our interview, Branden Burden '05 jumped for the receiver. It wasn't an emergency, and since he's been at the Cash Mine in Boulder County, they've never had an emergency, but the possibility weighs on him. "I hate it when that phone rings," he said, returning to his seat.

Burden is the mine engineer for this Mount Royale Ventures mining operation situated 10 miles west of Boulder. Of the 33 employees there, seven are Mines alumni. Matt Collins '04 is the mine manager; his wife, Lina Collins '07, is the environmental engineer; Chris Emanuel '05 is the mill engineer; Jim Paschis '73 is their geologist; Donovan Smith '07 is the associate mine engineer; and Murray Watts '68 is the engineer responsible for core drilling.

Cash Mine is currently Colorado's only active underground gold mine. Located at 8,500 feet on a hill overlooking the historic mining town of Gold Hill, it is also just a stone's throw from one of Colorado's earliest gold discoveries, the Gold Run strike of 1859. Since it was patented in 1872, the mine has remained operational much of the time, and consequently it is a treacherous labyrinth of vertical shafts and drifts (horizontal tunnels), many of which aren't mapped. "Small mining is very different," Burden says. "There's a lot of risk involved."

The company is close-knit with a sense of family that levels distinctions across the organization. Smith, who now oversees underground safety systems, jokes that perhaps his most important job of the day is showing up at 5:30 every morning to light the wood stove in the miners' dry room. And when there's a need, they all pitch in. "It's more than just a job for us. We all get down and dirty from time to time to help each other out," Burden says, describing how engineers sometimes fill in as miners or welders. New engineers joining the mine complete a rotation, working on every aspect of the operation before settling into their specific job.

The strong sense of community within the company is echoed in their relationship with the neighboring community of Gold Hill (pop. 220). Burden is a volunteer on the Gold Hill Fire Department, as are several other employees. They encourage locals to walk the trails on the mine's 455 acres of land at the edge of town. And the children at the Gold Hill Elementary School know Burden: once he led the 26 students on an afternoon walk to explain the dangers of playing around old mines (the hills are riddled with abandoned shafts); another time he went to the school to teach Civil War history dressed as a Confederate soldier.

Matt Collins also maintains ties to the Colorado School of Mines Mining Engineering Department. He encourages students from the department to visit and welcomes interns. Collins believes a small mine with a small staff can offer a breadth of experience that students won't get in a larger operation. Smith, who first came to the Cash Mine to visit a friend interning there, found it so much to his liking that he left with a job: "Coming out of school, I wanted something smaller," he explains.

In the near future, Collins wants his team to break new ground on another front. Protective of their local environment, he wants the Cash Mine to reach a point of zero-waste. They already follow a rigorous set of environmental protection standards. For example, all excavated material that could leach harmful minerals into nearby waterways end up in their double-lined tailings pond. And starting this summer, he plans to begin putting tailings back underground and to use the remaining excavated materials to improve infrastructure. Collins is proud of these safeguards. "Our environmental controls are almost certainly more advanced than any small mining operation in Colorado," he says.

While striving to protect the environment around them, their main focus is on finding gold. To do this, they are digging new tunnels in the mountain, following what look to be promising veins. The original Cash Mine consists of nine levels and is approximately 750 feet deep. Mount Royale Ventures has entered from the side of the mountain, at level three, and is currently mining upward. Their strategy will be to clean out all of the higher levels before digging any deeper.

One of the biggest challenges they face is relearning the art of highly selective narrow vein mining. The technique involves mining vertically up through a vein, but it has been out of use for so long that one of their best sources of information is a manual written in 1918. "There are only a handful of people alive who know how to do this, and we're employing most of them," Burden says with a laugh, holding up the book.

After two years of development and preliminary work, the actual mining of gold ore began just last fall, and now the real challenge is under way. Digging new tunnels in an old mine is a risky business and, as they dig, the crew is finding old workings that aren't always mapped. Cautious of cracking a watercourse, which could flood the mine, they work carefully, placing new timber and track as they go and building their ore chutes where they find productive veins.

Currently, they pull 50 tons of ore from the mine each day—a very small operation in the world of mining. The material is processed onsite in the mill to concentrate the ore, after which it is placed in huge bags and trucked to central Mexico to be smelted. They are averaging about three quarters of an ounce of gold per ton of rock extracted, which is up from last fall when they were getting a tenth to half-an-ounce per ton.

Careful analysis and modeling is one way they are improving results. The richest ore is found in a one-foot-thick, almost vertical vein that runs through the mountain. Each time they blast inside the mine, they take samples, assay the rock and add the information to a growing database. The database plots results on a three-dimensional model of the mine, and Collins has written algorithms to interpret trends in the vein and project where they will achieve the best results. Just a few weeks ago, he zeroed in on a new area to mine and found it was directly beneath a stope that had been mined decades ago with considerable success. "That was an 'aha' moment," says Collins.

While they use plenty of state-of-the-art technology, they also have some antiques in operation. Their primary and secondary crushers were built in the 1920s (replacement parts are scavenged or custom-made); at the face they use jack leg drills introduced in the 1930s that run on compressed air; and explosives are still detonated with fuses that burn. "They are safer," Burden explains. "With all the lightening we get up here, you don't want to start wiring up electronic fuses."


Left to right: Brandon Burden '05, Matt Collins '04, Lina Collins '07, Chris Emanuel '05, Jim Paschis '73

Their old equipment and the history of the area reinforce a sense of connection Collins and Burden feel to the past. "I'd like to see how this place looked 100 years ago," Burden says. "To see what the town looked like and how they worked." And he wonders what kind of life his counterpart engineers at the Cash Mine led. What were their hopes and dreams? What did they achieve? Where did they come from? What would they think if they saw the mine today? And if they met, what would they talk about?

It would be a fascinating conversation to be sure. The differences would be many, but so would the similarities. In fact, there's a good possibility they would have graduated from the same university.