No kiddin'! I think some of those chemicals have a half life of 99 years! Hell DDT would be safer!
Just as a frame of reference:
The homes that are around the actual Love Canal toxic waste dump in Buffalo will be safe for human habitation . . . in about 10,000 years.
Grind up DUmors and fertilize the soil? Maybe to eradicate pot/coca plantations . . . for 10,000+ years . . .