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科学美国人60秒:Burying Coal Ash for Good

2013-11-22来源:scientificamerican
What happens when 900 million metric tons of coal get burned? Roughly 100 million metric tons of coal ash is created, a residue laced with nasty elements like arsenic, lead and mercury. We perform this transformation every year in the U.S.

Storing all that ash is a challenge. That's why roughly 4 billion liters of the toxic stuff mixed with water was left to sit in a massive pond near Kingston, Tennessee. Five years ago on December 22, that pond burst its walls, drowning more than a square kilometer of land and killing portions of the Emory and Clinch rivers. The Tennessee Valley Authority has been cleaning up the so-called Christmas coal ash flood ever since.

But such catastrophic events are not the only way coal ash gets into our waterways. Rainwater can percolate through the ash when it’s improperly stored. A new report from a non-profit advocacy organization called the Environmental Integrity Project shows that the groundwater near TVA coal-fired power plants is contaminated with a toxic stew of elements.

The issue extends well past TVA jurisdiction. More than 580 coal ash sites exist across the U.S. We should work to get all that ash safely disposed of before another five Christmases pass. 

—David Biello