We’re used to seeing situations where accelerated, manmade erosion is causing a problem: construction sites without the necessary sediment and erosion control measures, say, or streams eroding because of increased runoff from upstream development. We know how to deal with these problems, even if we don’t always get it right. But erosion can happen on a much more dramatic scale as well, as is now happening in parts of China’s Shanxi province. The cause? Coal mining, which has literally undermined hundreds of communities, causing them to crumble and sink.
Pre-conference workshops Repairing Entrenched, Incised, and Degraded (Urbanized) Streams – Techniques and Case Studies Monday August 28, 2017 and BMP Selection to Improve Your Watershed Monday August 28, 2017. You may register for these without also registering for the annual conference. Download the StormCon Conference Program here.
As this Reuters article explains, as much as 10,000 square kilometers of land in China is affected in some way by mining activities. Some now-abandoned mining pits are eroding, leaving villages to “totter precariously on the brittle slopes,” as the article says. In other cases, mines were excavated beneath existing villages, which are now subsiding. Such situations occur in other regions of the world where mining activities take place, but China’s huge coal boom over the last 30 years—declining now because of dropping coal prices and a preference for cleaner forms of energy—combined with lack of government oversight has made the problem especially widespread there. One area of Shanxi has 19 documented “geological disaster zones” within a space of only 5 square miles, including 55 landslides, 950 cracks in the ground, and 808 incidents of mine subsidence.
The problems are so great in many areas as to be unfixable, and Shanxi province is now in the process of relocating 655,000 people from the unsafe regions; the cost of relocation alone is estimated to be $2.37 billion, and that doesn’t include other economic losses. Hundreds of thousands of additional people need relocate but can’t afford—and have not yet been given government funds—to do so. Mining firms are supposed to pay “subsidence fees” to help address the problems after a mine closes, as well as fees to clean up mine wastes and for other forms of remediation, but not all of them pay the required amount.
Despite efforts to move to cleaner energy, coal is still by far the greatest source of power in China; the goal is to reduce it to 62% by 2020. Even so, there is overcapacity in the coal industry, and many additional mines are being shut down. The government is encouraging developers to build solar and wind farms on the abandoned coal mining sites, which are now suitable for little else. Some successful solar demonstration projects have already been set up. Although earlier this year solar power made up just 0.6% of the country’s electricity generation and wind power 3.6%, those numbers are increasing rapidly; China now installs more photovoltaics than any other country and has the largest solar-power-generating capacity in the world.