The Lasting Damage of the Tennessee Coal Ash Spill

Six months later, scientists have a better idea the full impact of the December 2008 coal ash spill

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Dear EarthTalk: What were the environmental impacts of the huge coal ash spill in Tennessee this past December?
-- Dave S, Lynnfield, MA

Environmentalists’ call for an end to the age of coal—one of the dirtiest and most common of all the fossil fuels we now use—took on new urgency this past December when some 525 million gallons of wet coal ash, enough toxic slurry to flood more than 3,000 acres of nearby land, spilled into the nearby Tennessee River and surrounding areas when a retaining wall at a power plant in the town of Harriman gave way.

The sludge destroyed 12 homes, though no one was directly injured. However, an unprecedented fish kill occurred in the Tennessee River and area tributaries in the aftermath of the spill. According to John Moulton, a spokesman for the Tennessee Valley Authority which owns the plant, a test of river water near the spill site found elevated levels of lead and thallium, both of which have been linked to birth defects and nervous and reproductive system disorders. He reassured locals that, although these substances exceeded safety limits for drinking water, they would be filtered out by normal water treatment processes.


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But some area residents aren’t so sure that they are safe from the effects of the spill, which is estimated to have been over 40 times bigger by volume than the infamous Exxon Valdez oil spill of 1989. Calling it an “environmental disaster of epic proportions,” Carol Kimmons, a local resident who works at the non-profit Sequatchie Valley Institute, told reporters that the nasty black ash flowed into “the water supply for Chattanooga and millions of people living downstream in Alabama, Tennessee and Kentucky.” She added that the spill was 70 percent bigger than a similar one in Kentucky in October 2000 (306 million gallons) that the U.S. Environmental Protection Agency (EPA) referred to at the time as “one of the worst environmental disasters in the Southeastern United States.”

More than a year after that Kentucky spill, researchers found levels of lead downstream from where the spill took place that were 400 times higher than the EPA’s safe limit. And levels of Beryllium were 160 times higher than acceptable EPA levels. “Coal contains huge amounts of heavy metals, and when coal is burned, the organic matter burns off, but many of the nasty chemicals stick around, in higher concentrations,” said Kimmons. “Also, coal is 'washed' using some really nasty chemicals, which are also left over in coal slurry.” The bottom line, she concluded, is that “coal slurry is really, really toxic stuff.”

Ironically, on the very same day as the huge Tennessee spill, a coalition of 39 non-profit groups delivered a letter to then President-elect Barack Obama asking him to overturn a pending Bush administration rule change that would ease regulations on coal waste disposal. The groups contend that coal ash has already polluted 23 states and that the proposed new rule would only allow more pollution and more risks to human health and the environment. Now-President Obama has pledged to undertake a comprehensive inventory of liquid coal ash waste and propose new regulations to ensure its safe disposal.

“This disaster proves that regulations around coal slurry impoundments need to be tightened, and not loosened,” says Kimmons. Only time will tell if verbal commitments from Washington materialize into help on the ground.

CONTACTS: Sequatchie Valley Institute, svionline.org; Tennessee Valley Authority, tva.gov.

EarthTalk is produced by E/The Environmental Magazine. SEND YOUR ENVIRONMENTAL QUESTIONS TO:EarthTalk, P.O.Box 5098, Westport, CT 06881; earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php. EarthTalk is now a book! Details and ordering information at: www.emagazine.com/earthtalkbook.

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