8 November 2010

The Persistent Trouble with Coal Ash

Posted by John Freeland

504-acre ash disposal ponds in Lake Erie, near Bay View Power Plant, Toledo.

While a graduate student at the University of New Hampshire over twenty years ago, I attended an evening lecture by a hydrologist visiting from what was then still the Soviet Union. Early in his talk about groundwater, he said there was an old saying that “to make something clean, you have to make something else dirty.” 

Thinking about that, it’s not always true, is it? Pasteurization is an exception to that “rule” as is chemical reformulation that takes a hazardous material and reacts it with something else to create less troublesome products: for example, treating acid mine drainage with neutralizing agents. But it’s true a lot of the time, like when coal-fired power plants are equipped to emit less air pollution.

Before cleaner air standards, power companies used to broadcast smoke stack emissions over the countryside. Under pressure to reduce smoke and soot, an eastern power company added spray scrubbers to reduce air pollution and ended up dumping the wash water in the Monongahela River.

Of the 130 million tons of coal ash produced each year in the United States, about 40 percent is recycled for beneficial uses, like making concrete or road pavement, and the rest ends up in storage ponds or landfills. In 2008, a tragic failure occurred in Tennessee when a 40-acre coal ash lagoon ruptured and sent 5.4 million cubic yards of ash into the Clinch and Emory Rivers. The toxicity of the ash is a topic of debate.

The coal industry is fighting the Environmental Protection Agency (EPA) over whether or not to regulate ash as a hazardous material or like household trash. Either way, the coal companies will likely need to put liners under the ash ponds to prevent leaching of mercury, arsenic, lead and other toxic constituents into the groundwater. If the ash is considered non-hazardous, the bulk of the regulation will be done at the state level; if hazardous, it will be regulated by the federal government.

As we hear assurances of “clean coal” technology, we should all remember that burning coal creates a potentially harmful residue. If it’s scrubbed out of the air where does it go? It looks pretty clear that, when it comes to coal ash, making the air clean means making the land and water dirty.