It’s a kind of Superfund superplant, a leafy organism designed specifically to devour the hazardous waste that industrial machinations and human carelessness have left in the ground. The genetically modified mutant plants suck heavy metals, such as lead and arsenic, out of the soil into their roots, stems and leaves, cleansing the contaminated soil. It’s an intoxicating vision: Imagine fields of these valiant plants fighting part of the $700 billion battle that the United States faces in mopping up polluted Superfund sites.