Growth of Mountaintop Mine, West Virginia, 1984-2009 March 15, 2010Posted by Jill S. Schneiderman in coal mining.
If a picture is worth a thousand words, what’s the worth of these two pictures?
The change in this landscape near Coal River, West Virginia (the meandering line towards the right quarter of each image) is due to the expansion of surface mining operations over 25 years. Why have the mining operations so scarred the land? Is it just that we humans don’t like to clean up after ourselves? If that were so, perhaps we’d have a solution to the problem (for the land if not for the atmosphere). But the fact is, extract solid resources from the earth, crush them, remove what we want and leave the rest (the gangue material), and we have increased the surface area to volume ratio of the original solid. Hence, the gangue can’t fit back in the hole from which we took the mined mineral:
Surface Area of cube with 2 unit length, width, height is: 6 x (2 x 2) = 24
Volume of cube with 2 unit length, width, height is: (2 x 2 x 2) = 8
Surface Area to Volume Ratio is 3:1
Surface Area of 8 1-unit cubes: 8 x 6 x (1 x 1) = 48
Volume of 8 1-unit cubes: 8 x (1 x 1 x 1) = 8
Surface Area to Volume Ratio is 6:1
The point? Surface area increases more quickly that volume. Breaking up a once solid material and trying to fit it back into the same area that it once occupied causes the waste material to expand beyond the hole that originally contained the original resource. As a result, the waste materials must be draped over the surrounding landscape.
For more information on this West Virginia location, visit NASA’s Earth Observatory site that provides further details about these images.