In 1980, more than 400,000 toxic waste sites existed across the United States. The Environmental Protection Agency declared 400 of these highly hazardous and in need of immediate attention. In just a few years, the number of these "Superfund" sites more than tripled. Though they constitute a shocking degradation of our landscape, Superfund sites are never seen by most Americans. In the course of one year (1985-86), David T. Hanson (born 1948) traveled...