The proposed research focuses on using genetically-engineered microorganisms to efficiently decontaminate hazardous waste sites. The natural ability of bacterial cells to degrade organic compounds will be enhanced using the techniques of genetic engineering. The goal will be to alter the genetic information of the cell such that the genes that code for the enzymes responsible for the degradation of 3-chlorocatechol will be uncoupled from their wild-type regulator machinery. By replacing the wild-type promoter with one that can be controlled externally, the bacteria can be engineered to degrade the recalcitrant compound at faster rates. In addition, modifying the enzymatic pathway will enable the bacteria to reduce the final residual concentration of toxic wastes in the soil below the level that is currently achievable.