quite honestly we are a global toxic waste dump...
I studied this stuff back in college... the soil was a rising concern then to the point of developing majors to deal with the hazardous waste and toxicity of soils.
While the maps on these superfund sites (by state) pinpoint the problem... what they do not illustrate is the plume that runs out from the point of the problem... sometimes fanning out hundreds of square miles and into ground water.