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Hard questions must be asked about heap leaching hazards

Nowadays there's lots of talk of how dangerous drilling in the Arctic is. Whether it's global warming, oil spills (remember that whole thing with BP in the Gulf?) or killing baby polar bears,

Nowadays there’s lots of talk of how dangerous drilling in the Arctic is. Whether it’s global warming, oil spills (remember that whole thing with BP in the Gulf?) or killing baby polar bears, there seem to be a lot of reasons why we should hesitate to start grinding the North Pole into ice cubes to get at that rich “black gold” underneath.

But all this talk of black gold overshadows another important natural resource issue: actual gold.

On Jan. 5, 2011 the Yukon News published a story by John Thompson regarding Victoria Gold Corporation’s proposal to start mining the Eagle Gold deposit in Dublin Gulch.

According to the article, the Eagle Gold deposit has an indicated resource of 2.7 million ounces of gold. While experts estimate this to be enough for a gold mine to remain operational for eight years, Victoria Gold’s president and CEO said “We think it’ll be there a lot longer.”

The article goes on to state that if Victoria Gold has its way, an open-pit gold mine will likely appear near Mayo by 2013, and along with posting record profits, the company would also create around 400 new jobs.

In 2008, I spent a month backpacking and canoeing in the Yukon. Since then the natural beauty of its mountains and rivers has kept me itching to return to what I thought of as “the place God would take his vacations.” So when I read in the article that Victoria Gold “plans to extract the gold by dousing giant piles of ore with cyanide,” I was a bit concerned.

I’m not a mining expert, but spraying cyanide all over the place just doesn’t sound very healthy.

After some research, I learned the process called “heap leaching” consists of spraying giant piles of ore with a cyanide solution and then collecting the solution after it has made its way through the piles and “leached” all of the precious metal from the ore. After separating the precious metals from the end solution, the cyanide is usually re-used in the heap-leach process or occasionally sent to an industrial water treatment plant for further filtration.

According to mine-engineer.com, “leaching gold from sulfide ores is difficult, at best. Generally, the recovery for cyanide leaching of sulfide or refractory ores is no better than 30 per cent which is not a worthwhile venture.” Furthermore, through this method the production of one gold ring can generate an incredible 20 tons of waste material. In addition to this, heavy rainfall makes it extremely possible for surplus water and cyanide solution to be discharged into the environment, posing serious water pollution problems. And unless weather patterns have not somehow magically changed the Yukon into a desert wasteland since I was there in 2008, I can tell you that it does rain a lot.

Heap leaching does not have the best historical record either.

In 1982, 2,953 litres of cyanide-tainted solution leaked from the Zortman-Landusky gold mine in Missoula, Montana. The mine, operated by another Canadian gold mining company, Pegasus Gold, poured 841 litres of cyanide solution onto lands and creeks. Scientific testing revealed the cyanide concentration levels of tap water were far above drinking water standards and the community water system was shut down.

Over the next two years, eight separate cyanide spills occurred. In 1986, 75 million litres of cyanide solution were released onto seven hectares of land after a cyanide solution pond overflowed during a heavy rainstorm. Children who went swimming in the creeks and rivers developed painful rashes on their bodies and had to be taken to the hospital, while animals that drank the solution died.

There are many other cases of heap leach mines spilling toxic cyanide into the environment and especially into community drinking water. Because of its heavy mining industry, Montana has been the site of many such disasters. In the 1990s Golden Sunlight leaked 19 million gallons of cyanide solution into domestic wells. At the Golden Maple mine, two cows were killed by drinking contaminated water. The Beal Mountain mine closed in 1998 after a massive cyanide spill, one that the Montana Forest Service and State have spent $5 million in public funds cleaning up by constructing a water treatment plant that will have to be operated indefinitely.

Furthermore, cyanide-leaching accidents are occurring all over the world. In January, 2000 a massive cyanide spill from a Romanian gold mine contaminated 250 miles (402 kilometres) of the Danube river and its tributaries, killing masses of fish and wildlife and contaminating the drinking water of over two million people.

As a result of such spills, the Czech Republic banned cyanide leaching in 2000. Courts in Greece and Turkey have ruled against cyanide-leach gold mine proposals because of the “potential risks to health and habitat.”

In addition to all this, heap leach mines are by no means small undertakings. Although readers of the 2011 News article might be soothed by the accompanying photograph of one small bulldozer being operated by two workmen, anyone who types “heap leach mine” into a Google image search will find photos of enormous gravel sites - giant graveyards of what used to be mountains.

As quoted in the Thompson article, “If the (Victoria Gold) project proceeds, ‘it’ll be the largest gold mine in the history of the Yukon,’ said Williams. ‘There are no other gold deposits in the Yukon that come close to our size.’”

Looking at the pictures of these rubble landscapes, it’s hard to imagine how much bigger they could get.

Now, I’m all for making profit and creating new jobs, but at some point we have to ask ourselves, “At what cost are we making money?” The Yukon hosts (in this author’s humble opinion) some of the world’s most beautiful natural wonders, and furthermore is inhabited by some of the kindest and greatest people I’ve ever met.

Do we really want to introduce such an obviously hazardous practice into one of the world’s last remaining natural havens, and furthermore put those people living there at serious risk for cyanide poisoning? In the very worst-case scenario, what was once a commercial hub for eco-tourists and outdoor adventurers, an incredibly rare and beautiful natural habitat and a source of clean drinking water for nearby communities could be destroyed. So yes, I’m a bit concerned. You should be too.

Jonathan Lowenthal is a junior at Tufts

University in Medford, Mass. and is majoring in English and Environmental Studies.



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