Editor's Note: Expedition Blue Planet, led by Jacques Cousteau's granddaughter Alexandra Cousteau, is traveling 14,500 miles of road over 138 days to investigate and film some of North America's most pressing water-use and management stories. Each week expedition members will file a dispatch from the field for Scientific American until the expedition concludes on November 12 in Washington, D.C. This is their second blog post.

"Do you know what the largest industrial spill in American history is?" Alexandra Cousteau asked the residents of Kingston, Tenn., today.

The Deepwater Horizon oil spill, some replied. Others got it bang on. "I'd say the fly ash spill in Kingston," said Terry Nickle as he unloaded his shopping cart.

"Well I'm from Kingston so it's the ash spill down here in the lake below me," Marilyn Black told Alexandra on her way into Food City to buy groceries. 

When the dike of the Kingston Fossil power plant's retention pond broke nearly two years ago, 1.2 billion gallons of toxic coal ash slurry spilled into the Clinch and Emory Rivers, roughly six times the volume of oil that gushed into the Gulf of Mexico this summer.

"Really?" one 26-year old mother replied when Alexandra told her this fact. "I would have never guessed."

Out of sight, still in mind

As we drove into Kingston Sunday morning to do vox pops (to survey the people of Kingston and see what they had to say on camera), we didn't know what to expect. The slanted morning sunlight licked the fog away to reveal lush green and the stacks of the Kingston Fossil power plant stood sentinel over the bucolic landscape.

I mean, where does over one billion gallons of coal ash slurry go? One statistic cited that the volume of ash spilled equaled that carried by 12 million cement trucks. It was difficult to square away the gentle thrum of a small town's morning routine with this fact.

The Tennessee Valley Authority's clean-up efforts have removed a lot of the sludge (much of which is landfill-bound by rail for Perry County, Alabama) and by all appearances the river has washed away the rest. But scratch the surface and artifacts of the spill appear, not least in the community itself. 

"It really made a mess on the Emory River and it's had a lot of local citizens really concerned about the quality of the water," Jeff Smith told us during his work break in the Kroger grocery store parking lot in Kingston.

"Everybody has to have it and clean drinking water is something that you don't really realize you have until you miss it."

Clean air, dirty water

The burning of coal used to pollute our atmosphere—which explains why remote rivers in the upper reaches of Alaska are tainted with mercury—but these days, scrubbers capture the byproducts of coal combustion. This coal ash, laden with heavy metals, is often disposed of in uncovered settling ponds that have a color palette befitting the land of Mordor.

"It is a pond with grey sediment but that grey sediment is full of 25 odd metals that you would never find in a normal wetland," John Peterson, a biology researcher at Auburn University in Auburn, Ala., said in a phone call.

Aquatic life populates the ponds nevertheless. "There's tons of stuff living in these areas," he said. Frogs lay their eggs in them. One settling pond even had a resident alligator, he recalled.

While you don't see hundreds of frogs floating dead in these ponds, they exact their toll nevertheless. Peterson's research and that of other toxicologists have found that frogs don't develop correctly and they don't reproduce like they normally would in the coal-ash ponds.

"It's kind of insidious because if there are a bunch of deaths you can say, ‘Oh there are a bunch of deaths'," said Peterson. Instead the coal ash ponds represent a slow, downward spiral for amphibian populations.

"Although events like the TVA spill are horrible, these large events are rare," Bill Hopkins, director of the Wildlife Ecotoxicology and Physiological Ecology Program at Virginia Tech in Blacksburg, Va., wrote in an email. "The more serious problems are related to every day disposal."

Today was like any other day for the people of Kingston. It had been over 450 days since the spill punctuated their lives and yet, for each and every one of those days, 600 coal ash landfills and waste ponds strewn across the country continued to leech toxins and the United States powered 46 out of every 100 light bulbs with "clean coal." For those of us who don't live with the Kingston coal ash spill in our back yard, it's easy to forget that every day choices add up to superlative catastrophes.

Scientific American related link:

Toxic Ash Pond Collapses in Tennessee by David Biello

Image: Alexandra Cousteau speaking with residents of Kingston, Tenn. Credit: © Blue Legacy/Oscar Durand