SYDNEY: Millions of litres of toxic sludge have spilled into waterways in Tennessee in what has been described as one of the worst environmental disasters in U.S. history.
A retaining wall from the coal-fired Kingston Fossil Plant in eastern Tennessee broke on December 22, 2008, unleashing more than four million cubic metres of ash slurry out into the community – enough to fill 520 Olympic swimming pools according to the local CBS news.
Despite the scale of the disaster, it has been little reported in the international media.
The spill from the plant, owned by the Tennessee Valley Authority (TVA, a federally owned electricity provider) covered over one square kilometre of nearby land and flowed into the neighbouring Emory and Clinch rivers, where it has devastated the local aquatic environment and put residents at risk.
“It began to hit me that this was an environmental disaster larger than any before experienced in the U.S.,” said Shea Tuberty, a biologist from the Appalachian State University in the neighbouring state, North Carolina.
Yet, the TVA has assured the public that the ash material, a by-product from coal burning – is only dangerous if consumed. Local residents and Tuberty, who has been studying the fish in the affected rivers, aren’t so optimistic though.
The impact for humans could manifest in several different ways, according to Tuberty, the most likely risk arising if the ash dries out later in the year under the summer Sun.
In that case, it is likely to become airborne, posing more of a threat to local residents’ health as the material can cause lung irritation, and possibly more serious damage.
Mercury, arsenic and lead
Toxic heavy metals, such as mercury, arsenic and lead, present in the ash, could also seep through the soil, eventually reaching local drinking supplies. Although this is currently not an issue, locals are concerned what might happen if nothing is done.
“The human impact [of the disaster] comes at many levels,” said Tuberty. “I believe there are few disasters of this kind that compare to this one.”
Even one month after the event, clean-up crews have seen fish with scoured skin, lost scales, and damaged gills coated in ash. One catfish collected had 34 grams of ash in its stomach and intestines, 8 per cent of its total body weight.
Experts are concerned that the toxins will make it higher up the food chain as these fish are preyed upon.
“At the top of the food chain the effects will be more exaggerated. Large predatory fishes and piscivorous birds can exhibit some of the most profound adverse effects,” Tuberty said.
According to Greenpeace, “Coal ash typically contains high concentrations of toxic chemicals like mercury, cadmium, and other heavy metals. Following the spill, local television and photographers captured large numbers of dead fish washed up on the shores of the river.”
Greenpeace is now calling for a criminal investigation into the matter.
Efforts have been made to clean up the area, but it’s not a small or simple job.