Gutting a business for pipes...how much to charge?

There was a guy here in Minnesota years back that thought he was making some easy money by taking a bunch of 55 gallon drums that were filled with some sort of powder that looked like ashes or such. He spread it out on his driveway to fill holes and build it up and such. Years later he and his family had many health problems and found out that what he spread on his driveway was hazardous material. Don't remember just what it was that was in the drums. It was back in the late 70's or early 80's I believe.