It was proved that the bacteria in a sheep's stomach that enable it to digest cellulose can also help clean TNT contaminated soil. The TNT breaks down completely, leaving no trace in the animal's feces. Why not plant grasses in TNT contaminated soil and set the sheep free to graze and clear the land at the same time. According to my estimations, a flock of 20 sheep could completely clear an acre of TNT residue in less than three years.