Environmental

Engineers raised questions about coal ash pond walls decades ago

For decades, engineers raised questions about the walls of an impoundment pond containing toxic coal ash at the Tennessee Valley Authority (TVA) Kingston, Tennessee coal-burning plant, according to the KnoxvilleBiz.com. They questioned the way the walls were built and argued that they were not initially designed to stand as tall as they did. Those concerns fell on deaf ears then, but now have a voice after the walls of the pond broke loose last December and dumped 1.1 billion gallons of toxic material on to 300 acres of an east Tennessee community and into the waters of the Emory River.

The engineers concerns about the stability of the pond walls are detailed in documents released earlier this year by the TVA. The documents were requested by the Tennessee Department of Environment and Conservation (TDEC) in an effort to pinpoint why the pond breach occurred in the first place.

The documents show that the dikes making up the coal ash pond were in frequent need of maintenance and re-engineering. TVA officials made decisions based on opinions of both in-house engineers and consulting engineers. The pond’s most recent stability inspection – which showed nothing that would indicate failure – occurred just two months before the spill.

So far, the utility has spent more than $68 million cleaning up the mess, and that cost is expected to rise to as high as $825 million. The utility also has spent $11 million to buy out property from locals affected by the spill. Additional expenses are expected to cover litigation, penalties and settlements.