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WILL SEVEN BE LUCKY FOR THE FORT KNOX MINE?
Domestic mine article by Harold Hough
At the Fort Knox gold mine near Fairbanks, Alaska, the future of the mine rests on the number seven – in this case, Phase Seven Expansion. The mine was permitted 16 years ago, and the mine’s ability to stay in production to 2018 depends on the expansion taking place now.
Although there is definitely more gold destined to come out of the Fort Knox Mine, the history of the area goes back over 100 years to the time of the Alaskan Gold Rush. An Italian prospector, Felix Pedero, discovered gold in the Fairbanks mining district in 1902, while many miners were working up in Nome. But, it was the jump in gold prices in the 1980s that encouraged a new look at the district. In 1984, a geologist found the quartz vein on what was to become the fort Knox Mine. After several changes in ownership, it ended up in Kinross’s hands in 1998 as a result of a merger with Kinam.
Originally much of the material came from the True North open pit (now undergoing final reclamation). Mining is now taking place at the Fort Knox Open Pit. High-grade ore is processed at the carbon-in-pulp mill, which has a daily capacity of between 33,000 and 45,000 tons per day. The mine site is located primarily on lands owned by the State of Alaska and the Mental Health Trust. It employs 400-425 people at the mine and mill, which operate on two shifts, 24 hours per day, 365 days per year.
In 2008, Kinross' Board of Directors approved the construction of a heap leach facility and expansion of the open pit mine, known as the Phase 7 Expansion. Fort Knox mines and stockpiles large volumes of low grade ore and mineralized waste material that cannot be economically processed at the existing mill. The heap leach facility allows the mine to process some of these low-grade materials, as well as zones of lower-grade ore that have not yet been mined.
The Fort Knox Expansion Project is expected to extend the life of the Fort Knox Open Pit to 2016. The project will also double the life-of-mine production to 2.9 million gold ounces, and will increase Fort Knox production to an average 370,000 gold ounces per year during the five years starting in 2010.
While the Phase 7 Expansion is extending the life of the mine, mine operators aren’t just relying on processing more ore and high gold prices to remain competitive.
They also have the Continuous Improvement Program (CIP), which was instituted at the mine in late 1999. A CIP Team, which included workers from several departments, looked at the problem and recommended purchasing a hydraulic ram to slam the bolts out of the liner. The results were spectacular. The $120,000 ram reduced downtime by several hours and the additional production paid for the expenditure in three months. “We are saving a few hundred thousand dollars a year now,” notes a manager who helped put the program together at Fort Knox.
THE CONTINUOUS IMPROVEMENT PROGRAM
Although improvement programs are a common sight at mines, the Fort Knox program is unique in that it wasn’t started with a big fanfare, only to disappear in a few months. According to Royal, the mine looked at different improvement processes to find one that would work the best. What they discovered was that the worse programs were the ones that relied on consultants. When the consultants were in place, the improvements were made, but they tended to be forgotten after they left.
Fort Knox took a year and a half to get the CIP in place. Overall control is given to a Steering Committee, which is made up of upper management. Their responsibility is to determine needs and priorities. When a problem is identified, they assemble a team from various departments and backgrounds that can “put their heads together” to find a solution.
One advantage of bringing in experienced people from several departments is that solutions can be found when someone “outside the loop” understands the problem. Royal tells of one program to reduce the amount of reagents needed to detoxify the cyanide used in production. The environmental person never realized how much detoxifying material was needed just to make minor reductions in cyanide levels. The solution allowed the mine to standardize its detoxification process, keep cyanide levels below legal limits, and save thousands of dollars.
Once an improvement is instituted, it is up to the team to monitor it. According to the mine, “What gets measured gets noticed. What is noticed gets done.” Otherwise, the improvement may be forgotten.
However, Phase 7 and the CIP program aren’t the only activities at Fort Knox. Last year Fort Knox undertook a 95,000 foot drilling program to expand reserves and set the stage for a Phase Eight. They are also finishing reclamation of the True North Pit. In addition, last year the Resource Development Council and the Alaska Conservation Alliance awarded Fort Knox Mine and the Alaska Department of Fish and Game the Second Annual Tileston Award. This award was established to recognize organizations, individuals and/or businesses that create solutions and innovations advancing the goals of economic development and environmental stewardship. Fort Knox and Alaska Dept. Fish and Game were selected for the reclamation and fishery development work performed on the Fort Knox Fish Creek wetlands.
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