NEWMONT TO CELEBRATE 90TH ANNIVERSARY
By Harold Hough  

            2011 is Newmont’s 90th anniversary, and it looks like it will be a good year to celebrate.  As of December 31, 2009, Newmont had proven and probable gold reserves of 91.8 million ounces and their revenue had increased by 26% since 2008.  That’s really good news considering gold prices are at all time highs and the Carlin Trend in Nevada is still producing gold.
            The crown jewels for Newmont are the gold mines in Nevada.  Newmont was an early proponent of Nevada and they began producing gold there nearly half a century ago.  Their position in the Nevada mining sector only increased when the Carlin Trend  became one of the most valuable gold properties in the world.  Today Newmont has 14 open pit mines, four underground operations and 14 separate processing facilities in Nevada.
            Gold Quarry, which is located 7 miles north of Carlin, Nevada opened in 1985.  It is currently Newmont’s largest open pit on the Carlin Trend – dubbed by many as the “most prolific goldfield in the Western hemisphere.” When it first began, mining at the site was originally expected to last six years. However, many subsequent discoveries and expansions have allowed it to continue operating.  The Leeville underground mine is just 15 miles north of Gold Quarry and was opened in 2006.
            60 miles north of Winnemucca is another underground Newmont mine.  The Midas Mine is a high grade ore operation that was begun in the late 1990s by the Franco-Nevada Mining Company.  It was acquired in 2001 by Newmont.
An early problem child for Newmont was the Phoenix Mine, which wasn’t producing the ore grades planned.  The Phoenix open pit gold and copper mine, located in the high desert, began production in 2006. Phoenix was part of the Battle Mountain Gold acquisition in January 2001 and has one of the largest milling operations in North America. Despite the problems, exploration has now found additional reserves that indicate that the mine will continue operations longer than the 20 year expected operational life.
            Another critical part of the Newmont Nevada operation is the Twin Creeks Mine.  Twin Creeks was formed in 1993 through the combination of the Santa Fe’s Rabbit Creek Mine and the Chimney Creek Mine, which was owned by Hanson Natural Resources.  Gold was first found in the area by Gold Fields Mining in 1984.  The high-grade ore (.2 ounces of gold per ton) and thin overburden made it an economic deposit, so the company began building a 2,200 ton per day mine in 1987.  Two years later the mine became part of Hanson during a corporate takeover.  By 1992, the mine had produced its millionth ounce of gold.
            Santa Fe Pacific Gold subsequently found promising mineral deposits in 1987 and within three years had built an oxide mill and heap leach facilities.
            Despite these two successful mining operations, there was still a massive untouched sulfide deposit that was too difficult for either of the mines to process.  It wasn’t until 1993, when the two operations were merged, that it became economically feasible to develop this vast deposit.  But, it was Santa Fe’s merger with Newmont that allowed the mine to really exploit the deposit.
            Operating several Nevada mines don’t necessarily make for a successful and profitable operation.  What has made Newmont’s Nevada operation successful is how they have managed to integrate them together. 
The problem for Newmont is that the 18 different open pits and underground mines produce dozens of different type of gold ore.  In fact, the Twin Creeks operation had eight different ores from 40 different zones.  Flotation might be better for one type of ore at the mine, while biooxidation would be better for another type of ore.  There is no single, perfect answer.
            The answer was to integrate all Newmont gold operations in Nevada and send the different ores to different processes at different operations in order to achieve the highest recovery rates.
            “That is the real advantage we have in Nevada,” said a Newmont spokesman.  “We have six different ways to process gold ore in Nevada in 15 different facilities - the widest variety of processes of any operation in the world.  We constantly have trucks moving up and down Interstate 80.”
            The key to optimizing gold recovery by using several processes is an Optimizer program that assigns an ore from a mine to a specific processing operation that will maximize recovery rates.
            While some of the Twin Creeks ore goes elsewhere, the rest of it and other material from Newmont properties are processed in a massive autoclave that provides a 90% recovery rate.  These autoclaves are 76 feet long, 22 ½ feet wide and weigh 950,000 lbs. each.  By heating and pressurizing the ore, it not only negates the carbon present, it meets the strictest environmental standards.  According to Newmont, pressure oxidation has higher capital costs than other methods, but the costs are predictable and it avoids the higher operational costs and disposal problems for the arsenic resulting from roasting and biooxidation methods.
            By having several processing alternatives, Newmont has managed to effectively increase its ore reserves in Nevada.  And, by using several processes, Newmont can increase the recovery rate at its current operations.
            The flexibility offered by these different processes was critical in deciding to open the Phoenix operation, which was near another operation and contained large low grade gold and copper deposits. 
            Newmont’s ability to climb to the top of the world’s gold producers is a testament to their ability to maximize gold production with what they have.  Rather than just focus on finding world-class ore deposits, they have been an innovator in world class mining solutions.  It’s one reason why 2011 should be a great 90th anniversary for Newmont.