"Bioremediation technologies use microorganisms to treat contaminants by degrading organic compounds to less toxic materials, such as CO2, methane, water, and inorganic salts. These technologies include intrinsic or enhanced bioremediation, which is the focus of this report, and can be performed in situ or ex situ under aerobic or anaerobic conditions. During enhanced bioremediation, amendments are typically added to the media to supplement biodegradation processes. Amendments include nutrients (such asnitrogen and phosphorus), electron donors (such as methanol or lactic acid for anaerobic processes), electron acceptors (such as oxygen for aerobic processes, ferric iron or nitrate for anaerobic processes), or microbes (bioaugmentation) (EPA 1994, EPA 2000)."