This is 99% Invisible.

I'm Roman Mars.

In 2008, a billion gallons of toxic sludge spewed across 300 acres of Tennessee in the

middle of the night.

It was just before Christmas.

I was a senior in high school, and I remember seeing this billion gallons of sludge covering this

town outside of Knoxville and thinking, wow, that looks awful. That's Jared Sullivan. For over 50 years,

a power company called the Tennessee Valley Authority, or TVA, had been burning coal at a power plant

near Jared's hometown. Burning all that coal helped bring electricity to the region,

but it also created a mountain of ash and waste. Over the years, this mountain grew to be 60 feet high and 84 acres wide.

And on December 22nd, 2008, the earthen embankment that contained this mountain of waste collapsed.

A lethal wave of coal sludge inundated the countryside.

If you pull up the footage and looked up on YouTube or whatever, it really sticks with you

because it is biblical in scope what happened.

This disaster came to be known as the Kingston coal ash spill, and the culprit wasn't a private company.

It was the TVA, a federally owned electricity provider that had been set up by the government during the New Deal.

Immediately after this happened, TVA's PR lackeys got on the news and basically said,

this stuff isn't toxic, no big deal, don't worry about it.

And 900 blue-collar workers from around the country descended on the site to help clean it up.

Everyone expected that they'd find bodies under the sludge.

It was a miracle that no one died that night.

The real tragedy came years later,

...