ACID ROCK DRAINAGE

HOW ONE OF THE MOST DANGEROUS CONSEQUENCES OF MINING IS DESTROYING THE PLANET

Sophie Watson

THE HISTORY OF MINING IN CANADACanada has long been fascinated and reliant on the precious resources and minerals that come from our land. As far back as 40,000 years ago, the first Aboriginal settlers were using various metals and minerals to create tools necessary for their survival, and we continued to take advantage of these minerals for building homes, utilities and tools as our nation developed. As the years progressed however, minerals became recognized for their value as precious resources, and held the allure of riches and fame upon discovery. As a country, we pursued that dream, creating more and more mines, earning great revenue and encouraging even more progress in the industry. However, with great success, comes great consequences, and the process of removing of these minerals is harming the environment in many ways.

• Early Mining

Pre-contact Aboriginals used resources such as gold, copper, silver and chert. The exploration and colonization of North America was partially influenced by the search for valuable minerals.

• 19th Century

Large scale industries were built for mineral extraction Quebec. Once the mines began to profit, and gold rushes brought extra revenue, settlement increased and the economy boomed. 2 of Canada’s most major mines opened after the construction of the CPR; Sudbury nickel and the Sullivan lead-zinc mine.

• 20th Century

In the 20th century, Canada began to emerge as one of the world’s leading producers of a whole range of minerals. Radium was discovered at Great Bear Lake, and gold in Yellowknife in the 1930’s. Raw materials were also in high demand after the second world war, and increased the expansion of the industry greatly all over Canada.

MINING AND OUR ECONOMY In Canada alone, we have more than 800 functioning mines, employing over 363,000 people. Canada is #1 in the world for the production of Uranium and Potash, and contributes nearly 5% of the economy, making it a fairly central industry.

Potash

Uranium

IMPORTANCE OF MINING IN CANADA

Because of it’s rich Geology, Canada is one of the largest mining nations in the world, producing more than 60 types of minerals and metals. The mining industry has paid over $71 billion in taxes and royalties to Canadian federal and provincial governments in the last decade.

Map of mining sites in Canada

WHAT IS ACID ROCK DRAINAGE?Acid rock drainage, sometimes known as ARD, refers to the acidic water created when sulphuric minerals are exposed to air and water. Through a natural chemical reaction, this produces sulphuric acid. This acid greatly impacts biotic life and the environment. Acid rock drainage

THE PROBLEMS

The metals dissolved in the water during ARD are extremely toxic. The ARD seeps out from mining sites and merges with other bodies of water such as rivers, streams, lakes. The dissolved metals poison the water and kill most biotic life. Toxins that are a result of ARD can sweep through great expanses of land, destroying ecosystem upon ecosystem.

Fish killed by Acid Rock Drainage. These fish were killed September 2009 along with 160 species of fish and salamanders in Dunkard Creek and the surrounding watershed because CONSOL Energy was discharging acid mine drainage.

ENVIRONMENT

Another major concern of ARD is the extensively long life of the sites. The rocks at acid rock drainage sites are capable of continuing to generate sulphuric acid for an unknown number of years, possibly throughout the entire future habitation of the regions. Some Roman mining sites in Great Britain are still generating problematic acid rock drainage, 2000 years after the initial mining.

LONGEVITY

30 year old mine site, still generating hazardous Acid Rock Drainage. This mining site could continue adding sulphuric acid into rivers and streams, increasing pH levels dangerously

A GLOBAL ISSUESince ARD is common wherever there are mines, it’s happening all around the world. As mining increases, so does the amount of sulphuric acid being created and joining major bodies of water. This means the environment is being damaged all over the planet by this one consequence of mining, and since the mine sites continue to generate the acid, there is almost no foreseeable end to the spread of the pollution. The United Nations has described AMD as a global problem, second only to global warming.

Berkeley Pit Water. The water has turned a dark red hue due to the toxic mixture of heavy metal poisons such as arsenic, lead, and zinc that has been dissolved in it. No fish can live there, and no plants line the shores. Only some rare kinds of microorganisms survive in the toxic water. The Berkeley Pit had become one of the deadliest places on earth because of ARD.

-Tinto River, Spain

- Libiola’s Mine, Italy

- Aznalcollar Mine, Spain

- Wheal Jane, Cornwall, England

- Idaho Springs, Colorado, USA

- Britannia Beach, B.C., Canada

- Iron Mountain Mine, California, USA

- Monday Creek, Ohio, USA

- Avoca, County Wicklow, Ireland

- West Rand Goldfield, South Africa

- Berkeley Pit, Butte, Montana, USA

Though these are just a few major selected sites, there are several thousand such sites worldwide. Acid Rock Drainage is a problem across the world, and unfortunately, the treatment for the polluted water is very expensive. In addition, ARD may prevent the successful reclamation of a mine site, because the toxicity of ARD inhibits plant growth.

WORLDWIDE ARD SITES

My favourite method, and possibly the most promising solution, is the use of microbes as a naturally occurring cleaning product.

“Biological treatment means that you use micro-organisms to clean the water, but only the organics and nutrients, such a sulphates,

nitrates and phosphates can be eliminated,” explains Jan Greben, who has been working on biological treatment of ARD since 1986. The work has been proven to reduce sulfate content within a lab

setting, but it has yet to be done on a larger scale. This process is also much less expensive than chemical treatments and is much more eco-friendly. All that’s needed for the process to work is a carbon source; the bacteria need to eat in order to do their job.

Although this process does not make water suitable for drinking, it becomes safe enough to be released into natural bodies of water

again. This solution also has the benefit of producing no chemical waste.

Because ARD is such a big problem, many carious solutions have already been proposed, with varying degrees of effectiveness and cost. To enforce any of these

solutions however, takes a great deal of political will, money and time.

POSSIBLE SOLUTIONS

SOURCES

"What Is Acid Rock Drainage." Mining Facts. Fraser Institute Publications, 2009. Web. 23 May 2015. <http://www.miningfacts.org/Environment/What-is-acid-rock-drainage/>.

Kardas-Nelson, Mara. "The Acid Mine Drainage Solution Bandwagon." The M&G Online. Mail&Guardian, 10 Dec. 2010. Web. 24 May 2015. <http://mg.co.za/article/2010-12-10-the-acid-mine-drainage-solution-bandwagon>.

“EARTHWORKS | Acid Mine Drainage." EARTHWORKS | Acid Mine Drainage. 3 May 2013. Web. 24 May 2015. <http://www.earthworksaction.org/issues/detail/acid_mine_drainage#.VWEWYhzUohk>

"The Worlds Deepest, Biggest and Deadliest Open Pit Mines." The Worlds Deepest, Biggest and Deadliest Open Pit Mines. Web. 24 May 2015. <http://www.losapos.com/openpitmines>.

"Mining Facts." Mining Facts. The Mining Association of Canada, 2014. Web. 24 May 2015. <http://mining.ca/resources/mining-facts>.