Fort Knox gold output dips, but will still be top producer


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The Fort Knox gold mine near Fairbanks is likely to keep its place as the state’s No. 1 gold producer in 2014.

The mine, northeast of Fairbanks, is expected to produce 390,271 ounces of gold in 2014, including 245,286 ounces from the mill at the mine and 144,985 ounces from a heap leach processing facility also at the mine.

Gold production in 2013 was 421,641 ounces. In comparison, the state’s No. 2 gold producer, the Pogo underground gold mine east of Fairbanks, produced 337,000 ounces of gold in 2013 and will produce a similar amount in 2014.

Fort Knox employs about 630 people, the vast majority who live in Fairbanks and commute daily to the mine.

Fort Knox mines a gold ore that is low grade, so large volumes of ore must be mined and taken to the process facilities to extract the gold. In 2013 about 63 million tons of rock were mined, a daily average of 173,000 tons.

The figures are from the mining company’s presentation last March at the Alaska Miners Association annual Fairbanks conference.

Of the ore that was mined, 14 million tons were processed in the mill at the mine, a facility that uses a mechanical equipment to crush ore that is supplemented with a chemical process to extract gold.

An additional 33 million tons of ore were placed on the heap leach, a facility that involves a controlled circulation of a cyanide solution to extract gold.

Fort Knox began producing in 1996 with its first gold “pour” in December that year. Last December the mine reached the 6 million-ounce mark in gold production.

Fort Knox is proud of its safety record, with 1.8 million hours worked with no lost-time incident at the time of the March presentation.

Operating the mine takes a vast fleet of equipment, including three 35 cubic-yard “shovels” and one 24-cubic yard shovel; three 24-cubic yard Caterpillar 994 loaders and one 16-cubic yard Caterpillar loader; 19 240-ton haul trucks; 9 190-ton haul trucks; 10 150-ton haul trucks; seven specialized drllls for drilling blast holes, and miscellaneous equipment including tracked bulldozers, rubber-tired “dozers,” graders, water trucks, excavators and loaders.

Running the operation and providing fuel and power requires a large budget, with $54 million spent in 2013 for fuel, for about 40,000 gallons used per day; $43 million spent for electricity, and about $120,000 per day purchased from Golden Valley Electric Assoc., the Interior power cooperative.

The mine also uses about 33 tons of explosives per day to break up rock for mining, 21 tons per day of grinding balls to crush ore (the balls wear out), and 31 tons of lime per day as part of the gold-extraction process.

Fort Knox paid $5.2 million in property tax to the Fairbanks North Star Borough in 2013 and about $18 million in state taxes and fees, according to the March presentation.

Tim Bradner can be reached at tim.bradner@alaskajournal.com.

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