Earlier this fall, the Defense Department missed a deadline to stop using a firefighting foam that has caused widespread contamination across the country.

While the military continues its transition away from the toxic foam, it's also beginning a massive cleanup that will take decades and billions of dollars.

In the small town of Eskata, Michigan, a group of citizens has been fighting

to hold the Air Force accountable for contaminating their waterways. In the first of our two-part

series, special correspondent Megan Thompson brings us their story.

Tony Spaniola and his family have been coming to their vacation home on Vanit Lake for decades,

a relaxing getaway in the wilds of Northern Michigan.

But in 2016, Spaniola received a troubling letter from the state.

I got a letter in the mail from the Michigan Department of Health and Human Services saying,

don't drink your water.

About a year later, Spaniola began noticing something strange on the lake.

It was in December, and my wife woke up and she said, I think it snowed last night.

There was foam piled up all along the shoreline. You could see it for miles.

All along. Spaniola had learned his tap water, the lake, and this bright white foam were all contaminated with toxic man-made chemicals.

It sends you into a different place. It's a shocking kind of thing. So the base is right across the lake. Yeah, you can see the buildings.

It turned out the chemicals were coming from the old Wartsmith Air Force Base.

This was a fire training area. Mark Henry is a retired environmental engineer for the state of

Michigan who worked at the base after it closed in 1993. There used to be a big concrete bowl out here with a simulated aircraft on it,

and then they would bring the fire trucks in and let the people practice.

They were practicing putting out jet fuel fires,

dowsing the burning planes with a special foam that's been used by the military since the 1970s.

It's made from a chemical called

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