Valley fills are valleys coal companies are basically using as a trash can. After clearing the mountain (and before the “BOOM”) they need a place to put the trees, top soil, and bushes. To the coal companies the ideal place is a valley where animals live and streams that supply water to people all around run. After the “BOOM” they need a place to put the rock and dirt and again the “ideal” place is a valley. They keep blowing up part of the mountain and pushing the rock into the valley fill until the stub of the mountain is equal to the filled in valley. Valley fills can be hundreds of feet deep. More than 2,000 miles of streams have been buried by valley fills. That’s longer than the distance from Atlanta, Georgia to Los Angeles, California.