Letter to the EditorProduce metals here, or in third-world country? First of all, the new proposed mining ventures are not mining “sulfide” any more than the mining industry that started in MInnesota in 1884 is an “oxide” mining activity. Yes, iron oxides have been mined for over a century in Minnesota. The proposed ventures are in fact planning to mine copper sulfide and nickel sulfides.
By: Roger A. Anderson, Lake County News Chronicle
First of all, the new proposed mining ventures are not mining “sulfide” any more than the mining industry that started in MInnesota in 1884 is an “oxide” mining activity. Yes, iron oxides have been mined for over a century in Minnesota. The proposed ventures are in fact planning to mine copper sulfide and nickel sulfides.
Many people are saying that copper sulfide and nickel sulfide mining cannot be done in an environmentally sound way. Most of the world’s copper and nickel production is produced combined with sulfur in the ore. If the metals cannot be produced safely here, then we should not use them. That will prevent the mining of “sulfide” ore worldwide.
I attended the Institute of Lake Superior Geology annual meetings in Ely from May 5 to May 9, 2009. I was able to get on the “Copper Nickel Deposits of the Duluth Complex” tour on May 5 and 6. This information is based on what I gathered during that field trip.
According to the field trip guide, every American born today will need 1,309 pounds of copper, 1.576 troy ounces of gold, 29,608 pounds of iron ore, 587,288 pounds of coal, 1,610,000 pounds of stone, sand and gravel, a long list of other mined products and 67,695 pounds of other metals and minerals during his or her lifetime. How much are you willing to cut from your lifetime use?
Northern Minnesota has world class deposits of copper (Cu) and nickel (Ni) with quantities of gold and platinum group metals. World Class means among the top 10 percent of the deposits of the particular metal in the world. We have the second-largest copper-nickel resource in the world. The largest is in South Africa. The second largest resource will probably be exploited. The goal is to do it in an environmentally sound way.
Serious exploration for Cu-Ni began in 1948 about eight miles south of Ely when the Spruce Road was built. Areas of strong copper mineralization were uncovered in an excavation used for road material. That area was explored to some extent in the 1960s. The area south of the Peter Mitchell mine (which supplies Silver Bay with iron ore) was explored in the 1980s. More than 2,000 holes totaling over 2 million feet of core has been drilled.
The ores range from 0.5 percent to 1.5 percent copper, 0.1 percent to 0.5 percent nickel and parts per million gold, platinum, and palladium. Yes, these are “sulfide” ores. The sulfur is associated with the valuable metals. Little or no sulfur is found in the country rock. So, the mining company has a powerful financial interest in getting the sulfur out before throwing away the waste rock.
At present there are four areas of interest for development. Starting in the east is the Nocomis (Duluth Metals) deposit south of the Kawishiwi River and Birch Lake on either side of Highway 1. That deposit has about $88 billion in reserves based on the exploration of about half of the lease area. The Birch Lake deposit goes under Birch Lake about two to three miles east of Babbitt. The ore is 1,400 feet to 2,500 feet below the surface. Both the proposed Nokomis and the Birch Lake operations would be underground. Recent news indicates that $2-3 billion will be spent on developing the project near Highway 1.
The third is the Mesabi deposit south and east of the Peter Mitchell mine. The last is the NorthMet deposit which is owned by PolyMet and located south of the Peter Mitchell Mine and west of the Mesabi deposit. Mining the NorthMet mine will be an above ground operation.
The NorthMet deposit/mine was the closest to opening in 2009. PolyMet purchased the old LTV taconite plant, tailings basin, and related properties several years ago. The planned Northmet mine is about two miles south of the Northshore Mining pit. The plan is to mine about 32,000 short tons of ore per day. The ore would be ground to a fine powder in the old LTV taconite plant. The valuable minerals, which contain most of the sulfur, will be separated from the waste rock by a floatation process. The concentrate would be shipped out of Minnesota for refining. The waste rock will be mixed with limestone to neutralize any sulfuric acid that would be produced and then deposited in the present LTV tailings basin. The water will be treated and reused in the operation.
NorthMet is seeking a 20 year permit to operate at 32,000 short tons per day. The total deposit has a 100 year mining life at that rate. It is in their interest to have a clean and environmentally sound operation so that their permit can be renewed several times to mine the whole deposit over about 100 years. Northmet also has to have a clean operation if the three other deposits will never be mined. These will be multibillion dollar investments and long term mining operations.
The metals (copper and nickel) will be produced somewhere. Will they be produced in Minnesota with a high level of regulation or will they be produced in a third world country with little or no regulation and the resulting environmental disaster?
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