Tuesday, March 13, 2012

How does mining affect the environment?

The major impact of mining on the environment is mainly due to the physical damage of the landscape and the production of large volume of harmful wastes. In general, only a small fraction of the ore is valuable, the remaining large part is waste (tailings). For example, in the Cu mining industry, only about a kilogram of the metal is extracted from one-half ton rock. (Ore is an economic term for a rock from which a mineral can be extracted profitably).

The figure above summarizes the environmental impact of mining and smelting. It shows that mining and smelting produce solid, liquid and gaseous wastes/contaminants. These cause serious environmental damage once they are discharged to the land (terrestrial ecosystem) and bodies of water (aquatic ecosystems) or when they are emitted into ambient air. In particular, they cause soil and water acidification, air, water, soil and plant contamination by trace elements, deterioration of soil biology and fertility, and soil erosion.

Studies have shown that trace metals remain in the soil for a long time ranging from hundreds to thousands of years. Cd, Ni, and Zn have a relatively shorter residence time in the soil than Pb and Cr which may remain for several thousand years. This simply means that it is not easy and cheap to rehabilitate an abandoned mining site. In fact, the physical destruction of the landscape can be irreparable. And more importantly, the health risk of the contaminants that have already entered the food chain can remain for a long time.

Photo: Manicani island, Eastern Samar. Source: www.nickelore.blogspot.com (Feb 2, 2012)

References

Skinner B.J., S.C. Porter, and J. Park. 2004. Dynamic Earth. An introduction to Physical Geology. John Wiley and Sons, NJ.

Dudka S. And D.C. Adriano. 1997. Environmental impacts of metal ore mining and processing: a review. Journal of Envi. Quality 26: 590-602.

10 comments:

Jess said...

Great post! You don't often see posts on the environmental impact of mining. Are you working on this at the moment?

I am doing a PhD on mine rehab, and always like to meet people in the same field.

Victor B. Asio said...

Thanks for your comment. Yes, we have done some work related to the environmental impact of mining. It would be nice to exchange scientific data and information with other researchers like you.

Timeless said...

Have you followed the work of Dr Don Marx and PHC Reclamatiom of mining sites ? I'm not even sure Don is alive still. The folks at Plant Health Care a few years back told me he was retired and his wife passed on.

Anyway they have some fascinating info on their site. Very glad I found your site. I know people in other parts of the earth are working within their area of ecosystems. Wish I was back in mine. I'm in Sweden, but a desert rat at heart.

I'll stop by regularly. My background is landscape supervisor from San Diego area. I had unconventional methods of maintenance in that i refused to use conventional scientific based chemicals either fertilizers or pesticides. For me it was mycorrhizae all the way.

Thanks for the posts Victor


Kevin

Victor B. Asio said...

Hello Kevin,
Thanks a lot for leaving a note. I appreciate it. Yes, I agree mycorrhiza enables plants to thrive even in the most hostile soil environment.
Victor

Timeless said...

I love soils and geology and looking for ways to restore it's health. When I was in high school over in the USA, I was with the Future Farmers of America (FFA) Program. We went on various competition contests around the state of California. You chose your favourite subject to compete in. Mine was Soil Judging and Citrus Judging.

Though my major subject was ornamental horticulture, Soil fascinated me and I did very well in it. The fun of the competition was a real learning tool. Sadly those programs have gone by the way side now.

I miss the deserts of the southwest because the geology is so exposed to everything. I look for ways now to take moonscape desert environment and turn them into places not necessarily productive to people, but nature in general which is a win anyway for mankind. To bad the wealthier governments who have their huge welfare programs can't create a conservation corps programs like the old days where people actually did conservation land management work and were paid for it as opposed to sitting at home collecting a monthly check and doing nothing for it.

Not only would they be taught a healthy trade, but also build up self-esteem and personal satisfaction of accomplishing something important.

Anonymous said...

What I do not understand is why does the Philippine government encourage mining? Can anyone explain to us?

Spectro Labs Limited, Delhi, India said...

Spectro analytical lab is best testing group company in world for
everything but in this case people life is most important thing
is
environment
. You always search good environment place for yourself.
so we can help to decide which places environment is best for you are not.


i like to read your blog site.nice blog.

Joenard Algones said...

hello sir, I am JOENARD S ALGONES an MS student here at Cebu Normal University, I am currently doing my THESIS about Carbon Sequestration and I am looking for a paper published or not published about soil fertility and how mining affects the fertitlity

thanks


Victor B. Asio said...


Hi Joenard,

Thanks for leaving a message. Please send me your email address so I can email you some published articles on the topic you are interested in.

Cheers!

vba

Anonymous said...

I am surprised there is no mention of Sudbury, Canada in terms of mining remediation. This has been a 40 year and counting success story that is in the process of being made into a protocol for global application.
The Sudbury Story is important due to 40 years of scientific research and trials to reclaim severely degraded mine sites. It is also a long term story of collaboration between Industry, Government, Community and Acedemia.