spraying a solution of manufactured bacteria over mine wastes and processing the liquid, workers can re- cover huge amounts of copper. "Bioleach- ing," which produced about 30 percent of the U.S. copper industry's output 1989, literally saved American copper compa- nies from extinction.
Some day, Debus says, it may be possi- ble to eliminate conventional mining alto- gether. Bacteria engineered to remove specific kinds of minerals may be pumped into the ground and then extracted and placed...